Source: UNIVERSITY OF NEBRASKA submitted to NRP
AN INNOVATIVE GREEN TECHNOLOGY TO MANUFACTURE NOVEL HIGH-BIOAVAILABILITY BIOACTIVE COMPOUNDS
Sponsoring Institution
National Institute of Food and Agriculture
Project Status
COMPLETE
Funding Source
AFRI COMPETITIVE GRANT
Reporting Frequency
Annual
Accession No.
1022199
Grant No.
2020-67017-31276
Cumulative Award Amt.
$468,000.00
Proposal No.
2019-06854
Multistate No.
(N/A)
Project Start Date
Jun 1, 2020
Project End Date
May 31, 2024
Grant Year
2020
Program Code
[A1364]- Novel Foods and Innovative Manufacturing Technologies
Recipient Organization
UNIVERSITY OF NEBRASKA
(N/A)
LINCOLN,NE 68583
Performing Department
Food Science & Technology
Non Technical Summary
The potential health benefits of many water-insoluble bioactive food compounds with disease-fighting potential are not fully realized due to their low bioavailability (the fraction of the nutrient absorbed and utilized in the human body upon digestion). Curcumin has received much attention as health-promoting food ingredients for their gut health-improving properties. However, incorporation of curcumin into foods is a major challenge because curcumin is a crystalline powder that is insoluble in water, as well as in the aqueous phase of the intestinal juice. Consequently, curcumin added to foods is not bioavailable. In the absence of methods to improve bioavailability of curcumin, curcumin's potential for efficiently improving human health will remain untapped.To fill this gap, our long-term goal is to develop simple, efficient, and green strategies to enhance the bioavailability of water insoluble bioactives. This project aims to develop an innovative and green manufacturing technology to form first-of-their-kind curcumin with improved bioavailability to be used as novel food ingredients.This technology will enable food manufacturers to add water-insoluble bioactives into foods to produce health-promoting foods in a clean, simple, and efficient manner and improve the health benefits of various water-insoluble bioactives. This project will bolster the food industry by transferring this new technology and novel food ingredients to food manufacturers and by maximizing the use of bioactives derived from agricultural products.
Animal Health Component
30%
Research Effort Categories
Basic
35%
Applied
30%
Developmental
35%
Classification

Knowledge Area (KA)Subject of Investigation (SOI)Field of Science (FOS)Percent
5015010202040%
5025010202035%
5025010200015%
5025010101010%
Knowledge Area
501 - New and Improved Food Processing Technologies; 502 - New and Improved Food Products;

Subject Of Investigation
5010 - Food;

Field Of Science
2020 - Engineering; 1010 - Nutrition and metabolism; 2000 - Chemistry;
Goals / Objectives
The long-term goal of this project is to develop simple, efficient, and green strategies to enhance the bioavailability of lipophilic bioactives. The main objective of this project is to develop an innovative and green particle formation technology to manufacture first-of-their-kind low-crystallinity bioactives with improved bioavailability. The specific objectives are:Design, fabricate, and characterize NSB,Reduce the size and crystallinity of CUR using NSB and SC-CO2, andDetermine the stability, bioavailability, and bioactivity of CUR-NP against gut inflammation in vitro and in vivo.
Project Methods
Objective 1. Design, Fabricate, and Characterize nanoporous starch aerogels (NSB)Effect of amylose and amylopectin content of the starch on the properties of NSB. NSB will be prepared from corn starches with varying amylose and amylopectin contents. Waxy (2% amylose, 98% amylopectin), high amylose (63% amylose, 37% amylopectin), and normal (23% amylose, 77% amylopectin) corn starches will be used to determine the effect of amylose and amylopectin on the pore size and surface area of NSB. Hydrogels will be formed from starch, then the hydrogel will be converted to alcogel via a solvent exchange process, and then the alcogel will be converted into NSB using supercritical carbon dioxide (SC-CO2) drying.NSB will be characterized for BET surface area, BJH pore size, and pore volume, and morphology. Surface chemistry and composition of the NSB will be studied. Quantitative elemental compositions, functional groups, zeta potentials, and hydrophobic and hydrophilic properties of the NSB will be determined.Objective 2. Design, Fabricate, and Characterize Low-Crystallinity Curcumin Nanoparticles (CUR-NP)Formation of CUR-NP using two novel methodsMethod 1: High pressure vessel of the SC-CO2 system will be divided into two equal compartments by a sintered filter (0.22 μm). An excess amount of curcumin (CUR) will be placed into the bottom compartment, and 1 g of NSB monolith will be loaded into the top compartment. Impregnations will be done in semi-dynamic mode to improve the diffusion of the CUR-SC-CO2 solvato complex into the NSB matrix. Then, the temperature will be decreased to room temperature (21 °C) at varying cooling rates (0.6-10 °C/min), and finally the vessel will be depressurized at different depressurization rates (0.5-4 L/min, measured at ambient conditions). A successive cooling process where the system will be cooled and heated and re-pressurized repeatedly to increase the CUR impregnation capacity will also be used. CUR impregnation capacity will be determined by HPLC. Samples will be characterized for their morphology, particle size, crystallinity, interaction between CUR-NP and the NSB.Method 2: A novel simultaneous NSB formation-CUR-NP formation process will be developed to form CUR-NP already impregnated in the NSB. In short, CUR will be dissolved in ethanol, and this ethanolic CUR solution will be used in the solvent exchange step instead of ethanol to form alcogel. Dissolved CUR-containing alcogels will be dried with SC-CO2. Effect of the CO2 flow rate during SC-CO2 drying on the impregnation capacity, CUR-NP size, crystallinity, and CUR-NP distribution in the NSB will be investigated.Effect of NSB's surface polarity on the CUR-NP formationThe starches will be first treated with solvents to remove the minor inherent lipids and then this NSB will be used for CUR-NP formation using Methods 1 and 2 at the optimized conditions to evaluate the effect of surface polarity on the impregnation capacity, size and crystallinity of the CUR particles.Mathematical modeling of the CUR-NP formationCUR-NP formation will be mathematically modeled for both Methods 1 and 2 using original NSB and the NSBs that were treated to remove the inherent polar lipids to understand the effect of surface properties on the mechanism of CUR impregnation, CUR-NP formation and properties.Up scaled process modelling, and cost optimization based on green engineering. An up scaled process for the two CUR-NP formation methods will be designed and simulated. Starting from the feedstock preparation, manufacturing, and storage of primary product, and other effluents will be modelled to produce mass and energy balances, list of equipment, and utilities for an assumed capacity. The process will be optimized with design spec, sensitivity analysis, optimization with constraints, pinch analysis, energy and CO2 emission rates, and safety analysis. Sustainability analysis including the life cycle assessment will be performed using the GREET model.Objective 3. Determine the stability, bioavailability, and bioactivity of CUR-NP in vitro and in vivo Incorporation of CUR-NP into model foods and determination of CUR-NP stability. CUR-NP will be incorporated into regular fat, low-fat and nonfat granola bars (solid & low water content) and into pudding (liquid & high water content). Mixture of crude CUR with pregelatinized starch or empty NSB will be used as controls in both food models. Morphology of the CUR-NP-incorporated granola bars and the puddings will be examined. The texture analysis of the samples will be performed to determine hardness, adhesiveness, springiness, cohesiveness, and gumminessSensory evaluationFood products containing CUR-NP will be compared against control products in a consumer sensory panel. Panelists will be asked to taste up to three samples of either granola bars or pudding that have been formulated to contain crude curcumin, CUR-NP, empty NSB, or no NSB. Overall, texture, appearance, color, and flavor acceptance will be evaluated. Flavor, texture, and odor attributes will also be rated for intensity.Chemical and physical stability of CUR-NP. The stability of the CUR-NP (control) and the CUR-NP in the above-mentioned food preparations will be investigated by a storage test over 3 months at room temperature and at refrigeration temperature (4 °C) to determine any degradation of CUR-NP during storage.Micelle formation. We will assess the partitioning of CUR-NP with micelles as micelle formation is a good indicator of bioaccessibility. Samples (CUR-NP and CUR-NP-incorporated food preparations) will first undergo sequential simulated digestion. Digestion experiments will be carried out (i) without any food to simulate the consumption of CUR on an empty stomach, and (ii) with food (granola bar and the pudding) to simulate the consumption of fat-free/low-fat food enriched with CUR. Samples of sequential simulated digestion will be separated into oil, aqueous (sub-phase containing micelles), and pellet phases by ultracentrifugation.Bioavailability and bioactivity of CUR-NP in human intestinal epithelial cells. Bioavailability will be determined using standard techniques in Transwell insert (Corning) by quantifying CUR and CUR glucuronides (cell lysate treated with or without 1000U β-glucuronidase) present in Caco-2 cell lysate following treatment with equivalent molar concentrations of CUR-NP or crude CUR. We will ascertain the bioactivity of CUR-NP vs. crude CUR in Caco-2 cells based on (i) the expression of pro-inflammatory cytokines TNFα and IL-6 by qRT-PCR, (ii) cyclooxygenase-2 abundance and mTORC1 activity by Western blotting.Animal studiesBioavailability of a single CUR-NP dose in mice. The CUR formulations will be gavaged to 9-wk old male C57BL/6J mices at ~2.5 mg CUR/mouse, i.e. 100 mg CUR/kg BW. Eight mice/group (8 mice x 2 treatments = 16 mice) will be used. Blood samples will be taken at 0, 0.25, 0.5, 1, 1.5, 2h post gavage with fluid replacement. Plasma CUR and metabolites (THC, HHC) will be analyzed by HPLC. CUR and metabolites will also be analyzed in stomach, caecum, small and large intestine contents.Bioactivity of CUR-NP in mice. The goal of these animal studies is to ascertain the protective effects of CUR-NP vs. crude CUR with respect to gut inflammation. Dextran sulfate sodium (DSS)-treated C57BL/6J mice will be used as a model of gut inflammation with ulceration but without adenocarcinoma.

Progress 06/01/20 to 05/31/24

Outputs
Target Audience:Academia: Professors and researchers at national and international academic institutions in food science and engineering, nutrition and health sciences, material science and engineering, bioengineering, and related disciplines. Undergraduate and graduate students: Undergraduate and graduate students in the Food Engineering Unit Operations and Food Lipids courses taught by the PD. Industry: Food, nutraceutical, and cosmetic companies. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?A food science PhD student, a Nutrition MS student, two postdoctoral fellows, and two undergraduate students from minority serving institutions were trained in supercritical fluid technology, bioavailability, bioaerogels, green food technologies, food engineering for human health, process design and advanced food analysis. The expertise in supercritical fluid technology in food processing in the U.S. is limited; therefore, training highly qualified personnel in this area is important for expanding green bioprocessing and bioengineering area in the U.S. The PD trained the PhD student and the postdocs on designing supercritical fluid systems, operating those systems, and their troubleshooting. One-on-one trainings with the PhD student and the postdocs provided the trainees with the skills needed to design and build supercritical fluid systems.Moreover, an extensive training on advanced food analyses was given to the PhD student. Postdocs' mentoring program aimed at preparing the postdocs for their careers in academia and industry. Incluidng the project into the food science and technology cirriculum enhanced undergraduate students' food engineering knowledge. How have the results been disseminated to communities of interest? Manuscripts were published in scientific journals and the findings were presented at the national and international scientific conferences.. Our project and findings were included in the undergraduate and graduate level FDST 465/865 Food Engineering Unit Operations course taught by the PD. The developed process and the bioaerogels were introduced to the food science students to show the role of food engineeirng in improving food quality, safety, and human health. The role of USDA in promoting food quality, safety, and human health via supporting research on developing novel foods and innovative food manufacturing technologies was demonstrated. The PD introduced the project and shared the findings with professors, graduate and undergraduate students in the NC- 1023 multi-institutional course/seminar series. This multi-institutional course provides a broad perspective of innovation as applied to food engineering. The course constitutes weekly presentations from 12 speakers on topics in different thematic areas. The online platform has given unique opportunities for students to meet their peers and faculty from across the county, create a peer network of researchers and mentors to learn from their experiences and build a sense of community. The PD was approached by several food and nutraceutical companies both in the U.S. and Europe to get more information about the technology and the products generated by this technology and to transfer the technology to industry. The PD had telemeetings with those companies to introduce this innovative technology. The readiness of the technology to transfer to industry was discussed. Seminars were given to industry scientists. The PD Dr. Ciftci received the LIST International Award in Bioinnovation (LIAB Award) with this project. Luxembourg Ministry of Economy attended PD's presentation during the award ceremony when Dr. Ciftci gave a livestream talk on the project. This talk and the award ceremony was broadcasted. Afterwards, a press conference was held by journalists to get more information about this technology. What do you plan to do during the next reporting period to accomplish the goals? Nothing Reported

Impacts
What was accomplished under these goals? The health benefits of many lipophilic (water-insoluble) bioactives, such as curcumin, are often limited due to their poor bioavailability. These bioactives, with disease-fighting potential, are crucial for addressing diet-related illnesses like gastrointestinal problems, inflammation, cancer, and obesity. Despite their potential, their low solubility in water limits their incorporation into functional foods, making it a challenge for the food industry to formulate effective products. Consumers' preference for "natural" and "clean" foods has further increased the demand for bioactive-enhanced foods. Lipophilic bioactives, in their crystalline forms, are generally poorly water-soluble, limiting their bioavailability. In contrast, amorphous forms of bioactives are more water-soluble and bioavailable. Thus, finding methods that reduce the crystallinity of bioactives and enhance their solubilization in digestive fluids is critical. To address this issue, we developed a green and efficient strategy to improve the bioavailability of lipophilic bioactives, focusing on curcumin (CUR) as a model compound. CUR is widely known for its health benefits but suffers from poor bioavailability. Our innovative particle formation technology creates first-of-their-kind, low-crystallinity bioactives with improved bioavailability. Objective 1: Design, Fabricate, and Characterize Nanoporous Starch Bioaerogels (NSB) We investigated the effects of amylose and amylopectin content in starch on NSB properties, such as surface area, pore size, morphology, and surface chemistry. The NSB were characterized, and we found that starch type significantly influenced bioaerogel properties. Higher amylose content resulted in bioaerogels with lower shrinkage and density, as well as higher surface area and porosity. We also produced new NSB by adding chitosan, further decreasing shrinkage and creating bioaerogels with improved oil-structuring capabilities. Development of Composite Bioaerogels: The addition of chitosan to the starch bioaerogels significantly enhanced their oil-structuring abilities. These aerogels were employed as porous templates for structuring liquid oils to form oleogels. Aerogels with higher amylose content exhibited superior oil-structuring capacity. The results indicate that both the starch type and the presence of chitosan profoundly affected the density, porosity, and oil-structuring properties of the bioaerogels. Developing Dual Nano/Macroporous Starch Bioaerogels: Using emulsion templating and SC-CO2 drying, we developed a new method for bioaerogel formation, creating dual nano/macroporous aerogels. Oil droplets were used as temporary porogens to form macropores, while nanoporous structures were preserved. This resulted in aerogels with internal morphology on two scales (macropores and nanopores) and high surface areas ranging from 156 to 190 m²/g. Superlight Macroporous Bioaerogels from Egg White Protein (EWP): We developed superlight macroporous bioaerogels from egg white protein using a green cold-gelation approach. These cold-set hydrogels were dried via SC-CO2 to create porous bioaerogels with three to five times lower density and significantly higher macroporous volume than heat-set bioaerogels. These bioaerogels were then used to structure liquid oils, resulting in solid-like, plastic oleogels with elastic modules exceeding 2.0×105 Pa. Objective 2: Reduce the Size and Crystallinity of Curcumin Using NSB and SC-CO2 Curcumin was impregnated into the composite aerogels using a single-step SC-CO2 drying process. Curcumin loading ranged from 24 to 27 mg/g NSB. In vitro digestion tests showed that curcumin-loaded aerogels significantly increased bioaccessibility by almost 30-fold. The curcumin-loaded composite NSB exhibited higher solubility and bioaccessibility, resulting in greater antioxidant activity compared to neat NSB. In addition to the single-step process, we developed a two-step process to form CUR-NP. First, NSB was formed from high-amylose starch hydrogels via SC-CO2 drying. Curcumin was then impregnated into dry NSB using a SC-CO2 impregnation process. This two-step process formed a CUR-SC-CO2 solvato complex, which diffused into NSB nanopores, followed by rapid cooling to precipitate curcumin. Impregnations were conducted at temperatures ranging from 40 to 120 °C and pressures up to 45 MPa. Ethanol was used as a co-solvent to enhance CUR solubility in SC-CO2, increasing impregnation capacity from 0.01% to 1.5%. Supercritical CO2-Driven Curcumin Impregnation into EWP Aerogels: We investigated curcumin impregnation into EWP aerogels using SC-CO2. Curcumin was uniformly distributed within the aerogel matrix, leading to enhanced solubility, bioaccessibility, and antioxidant activity. Cold-set EWP aerogels demonstrated higher curcumin loading capacity and bioactivity than heat-set aerogels, while digestibility studies confirmed the efficient breakdown of these aerogels by digestive enzymes. This highlights their potential as food-grade carriers for controlled release and nutraceutical delivery. Fabrication of Dual Functional Oil-in-Water Structured Emulsions: Curcumin-loaded EWP aerogels were used to create oleogels, which were then used to form oil-in-water emulsions with fish oil. These structured emulsions significantly enhanced curcumin bioaccessibility and oxidation stability, offering superior performance compared to regular emulsions. Light stability of curcumin was also enhanced within these emulsions. Mathematical Modeling, Technoeconomic and Sensitivity Analyses: A mathematical model was developed to simulate curcumin loading into NSB, identifying critical factors such as aerogel shape, temperature, and curcumin concentration. Rectangular-shaped aerogels performed better than cylindrical or spherical ones in terms of curcumin loading performance. Technoeconomic analyses of the processes were performed. Objective 3: Stability, Bioavailability, and Bioactivity of CUR-NP Against Gut Inflammation CUR-NP showed excellent stability, with no degradation after two months of storage at room temperature. When tested in yogurt, CUR-NP exhibited bioaccessibility of 12% on Day 1, increasing to 18% by Day 21, while free curcumin degraded by 30%. In granola bars, CUR-NP also demonstrated superior bioaccessibility and stability. Bioavailability and Bioactivity in Human Intestinal Cells: CUR-NP was more bioavailable in Caco-2 cells than free curcumin, with higher transport across the epithelium. CUR-NP also inhibited mTORC1 activity more effectively in Caco-2 and HT-29 cells. Animal Studies: CUR-NP demonstrated a 6.6-fold increase in bioavailability compared to free curcumin in animal studies, with no significant difference in glycemic response between CUR-NP and free curcumin. These findings highlight the potential of CUR-NP for use in functional foods to improve human health. IMPACT: This research has the potential to significantly enhance the U.S. agriculture and food systems by improving the bioavailability of water-insoluble bioactives through the innovative formulation of starch bioaerogels. The findings are expected to drive the development of food systems that optimize the cost-effectiveness of bioactives, benefiting both food manufacturers and consumers. By increasing bioavailability, less bioactive will be required to achieve the desired health effects, reducing waste, and promoting resource efficiency in agricultural production. This research supports the production of health-promoting foods and maximizes the use of bioactives derived from plant-based agricultural products, thus contributing to sustainability by lowering water and energy consumption in both food manufacturing and agriculture. The long-term implications include expanding the use of bioactives in various food products, amplifying the health benefits of bioactive-enriched foods, and fostering a more sustainable, resource-efficient food system.

Publications

  • Type: Journal Articles Status: Published Year Published: 2024 Citation: Alavi, F and Ciftci, O. N. (2024). Single-step simultaneous composite starch aerogel formation-high bioaccessibility curcumin particle formation. International Journal of Biological Macromolecules, 264, 129945
  • Type: Journal Articles Status: Published Year Published: 2024 Citation: Alavi, F and Ciftci, O. N. (2024). Increasing the bioavailability of curcumin using a green supercritical fluid technology-assisted approach based on simultaneous starch aerogel formation-curcumin impregnation. Food Chemistry, 455, 139468.
  • Type: Journal Articles Status: Published Year Published: 2023 Citation: Alavi, F and Ciftci, O. N. (2023). Superlight macroporous aerogels produced from cold-set egg white protein hydrogels show superior oil structuring capacity. Food Hydrocolloids, 136, 108180.
  • Type: Journal Articles Status: Submitted Year Published: 2024 Citation: Alavi, F. and Ciftci. O.N. Supercritical CO2-driven curcumin impregnation into egg white protein aerogel: effect of gelation method on curcumins loading capacity, bioaccessibility, and bioactivity. Food Hydrocolloids.
  • Type: Journal Articles Status: Submitted Year Published: 2024 Citation: Alavi, F. Majumder, K., and Ciftci. O.N. Designing curcumin particles with improved bioactivity and bioavailability using aerogels and supercritical fluid technology. ACS Applied Materials & Interfaces.
  • Type: Journal Articles Status: Submitted Year Published: 2024 Citation: Momen, S. and Ciftci. O.N. Forming high bioaccessibility curcumin formulation through a powder-to-powder mass transfer approach using supercritical fluid technology and starch aerogel. Chemical Engineering Journal.
  • Type: Journal Articles Status: Submitted Year Published: 2024 Citation: Alavi, F. and Ciftci. O.N. Fabrication and characterization of dual functional oil-in-water structured emulsions from curcumin-loaded egg white protein aerogels. Submitted. Food Chemistry.
  • Type: Journal Articles Status: Submitted Year Published: 2024 Citation: Alavi, F. and Ciftci. O.N. Modulating microstructure and hydrophobicity of protein aerogels tod improve their absorption efficiency. Chemical Engineering Journal.
  • Type: Journal Articles Status: Submitted Year Published: 2024 Citation: Liu, L., Alavi, F., Ciftci, O.N. Performance of the high bioavailability curcumin-starch aerogel formulation in real food systems and their storage stability. Food Research International.
  • Type: Journal Articles Status: Other Year Published: 2024 Citation: Mathematical modeling of curcumin impregnation into starch aerogels using supercritical carbon dioxide. In preparation.
  • Type: Journal Articles Status: Other Year Published: 2024 Citation: Mathematical modeling of curcumin diffusivity into starch alcogels during simultaneous curcumin impregnation-aerogel formation process. In preparation.
  • Type: Journal Articles Status: Other Year Published: 2024 Citation: Technoeconomic analysis of manufacturing novel high bioavailability curcumin formulation using bioaerogels and supercritical fluid technology: Part 1- Two step process. In preparation.
  • Type: Journal Articles Status: Other Year Published: 2024 Citation: Technoeconomic analysis of manufacturing novel high bioavailability curcumin formulation using starch bioaerogels and supercritical fluid technology: Part 2- Single step simultaneous impregnation-aerogel formation process. In preparation.
  • Type: Journal Articles Status: Other Year Published: 2024 Citation: Technoeconomic analysis of manufacturing novel high bioavailability curcumin formulation using protein bioaerogels and supercritical fluid technology. In preparation.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2024 Citation: Invited Talk: Ciftci, O.N. Engineering the Future of Food: Designing Future-forward Food Structures with Supercritical Fluid Technology for Health and Quality. 2024 Future of Food Symposium: Innovations, Challenges, and Perspectives, May 16-17, 2024, Montreal, Canada.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2023 Citation: Invited Talk: Ciftci, O.N. A new green approach to forming curcumin particles with improved bioactivity and bioavailability using bioaerogels and supercritical fluid technology. International Society for Nutraceuticals and Functional Foods, December 10-13, 2023, Hawaii, USA.
  • Type: Theses/Dissertations Status: Published Year Published: 2024 Citation: Alavi, F. Developing an innovative and green aerogel formation technology to manufacture low-crystallinity curcumin with improved bioavailability.
  • Type: Journal Articles Status: Other Year Published: 2024 Citation: Liu, L., Rose, D., Ciftci, O.N. Sensory properties of the curcumin-impregnated starch aerogels. In preparation.


Progress 06/01/22 to 05/31/23

Outputs
Target Audience:Academia: Professors and research staff at both national and international academic institutions. Not only in food science and engineering, also in nutrition, health sciences, material science and engineering, bioengineering and related disciplines. Undergraduate and graduate students: Undergraduate and graduate students in the FDST 465/865: Food Engineering Unit Operations and FDST 896: Novel Trends and Innovation in Food Engineering courses (as part of the USDA NC-1023 Multistate Project) taught by the PD Dr. Ciftci. Industry: Food, nutraceutical, and cosmetic companies both in the U.S. and other countries. Changes/Problems:Animal studies in the Co-PD's lab required more time (especially the gut inflammation studies); therefore, we already requested a no-cost extension to finalize the animal studies outlined in Objective 3. What opportunities for training and professional development has the project provided?A food sciencePhD student, a Nutrition MS student, and two postdoctoral fellows were trained in supercritical fluid technology, bioavailability, bioaerogels, green food technologies, food engineering for human health, process design and advanced food analysis. The expertise in supercritical fluid technology in food processing in the U.S. is limited; therefore, training highly qualified personnel in this area is important for expanding green bioprocessing and bioengineering area in the U.S. The PD trained the PhD student and the postdocs on designing supercritical fluid systems, operating those systems, and their troubleshooting. One-on-one trainings with the PhD student and the postdocs provided the trainees with the skills needed to design and build supercritical fluid systems.Moreover, an extensive training on advanced food analyses was given to the PhD student. Postdocs' mentoring program aimed at preparing the postdocs for their careers in academia and industry. How have the results been disseminated to communities of interest?- Manuscripts were published in scientific journals. - Findings were presented at international scientific conferences that included attendees from both academia and industry. - Our project and findings were included in the undergraduate and graduate level FDST 465/865 Food Engineering Unit Operations and FDST 896 FDST 896 Novel Trends and Innovation in Food Engineering courses taught by the PD. Our technology and the bioaerogels were introduced to the food science students to show the role of food engineering in improving food quality, safety, and human health. The role of USDA in promoting food quality, safety, and human health via supporting research on developing novel foods and innovative food manufacturing technologies was demonstrated. - The research lab of the PD hosted high school students. The project and the novel food materials and technologies developed in this project were introduced. What do you plan to do during the next reporting period to accomplish the goals?We will continue working on Objective 3 that has lengthy animal studies on bioactivity. We will test the effect of our product on gut inflammation in animals. Once the reuested IRB is approved, we will perform the sensory analyses of the foods prepared by our product. We have been working on the mathematical modeling of the process. We will submit manuscripts on the modeling studies. In addition to the reported publications, we have 4 manuscripts ready for submission. We will submit those manuscripts to journals for publication and other manuscripts from the Objective 3 will be prepared and submitted to journals.

Impacts
What was accomplished under these goals? The health benefits of lipophilic bioactives are hindered by low bioavailability (absorption in human body) due to poor water solubility. Despite challenges, these bioactives hold potential for combating diet-related diseases. The food industry prioritizes developing bioactive-enriched foods, but incorporating water-insoluble bioactives presents challenges. They are typically crystalline powders, poorly soluble in water and fats. This limits bioavailability, and a solution is needed to decrease crystallinity. To fill this gap, this project develops an innovative and green manufacturing technology to form first-of-their-kind bioactive compounds with improved bioavailabiity to be used as novel food ingredients. This technology will enable food manufacturers to add water-insoluble bioactives into foods to produce health-promoting foods in a clean, simple, and efficient manner and improve the health benefits of various water-insoluble bioactives. Longer term, this novel approach will (i) maximize the utilization of the bioactives derived from agricultural products; (ii) improve public health through simple diet; (iii) enhance the cost-benefit ratio of bioactives; (iv) reduce food wastes; (v) avert toxic chemicals & environmental pollution; (vi) lower the costs of handling, storage & transportation of bioactives. Objective 2. Reduce the size and crystallinity of curcumin (CUR) using nanoporous starch bioarogels (NSB) and supercritical carbon dioxide (SC-CO2) Modulation of microstructure and surface chemistry of NSB for tuning the bioaccessibility and the release pattern of curcumin: After obtaining the highest impregnation capacity with the high amylose starch (72%), the surface chemistry and microstructure of the high amylose NSB were modulated by the incorporation of chitosan into the structure of the NSB to obtain a composite NSB. The starch hydrogel precursors were prepared from high amylose starch in the presence of 0.50, and 0.75 wt.% chitosan. Then, the single-step simultaneous aerogel formation-curcumin deposition method was applied to impregnate curcumin into the NSB through SC-CO2 drying technology. Specific surface area and scanning electron microscopy (SEM) analysis revealed the highly porous internal structure of the curcumin-loaded aerogels, whereas composite starch/chitosan aerogels showed a more open porous structure and lighter weight. Confocal microscopy and fluorescence spectroscopy analysis confirmed the attachment of curcumin molecules to the hydrophobic cavities of the aerogels (Fig. 2). The impregnation capacity was 24-27 mg curcumin per gram of NSB depending on the composition of the aerogels. In vitro digestion tests showed that the loading of curcumin in the aerogels significantly enhanced the bioaccessibility of curcumin in the simulated gastrointestinal fluid by almost 30 folds. Furthermore, the in vitro digestion experiments showed that the bioaccessibility of the curcumin loaded in starch-chitosan composite NSB was higher than that loaded in neat NSB. Due to their higher solubility and bioaccessibility, curcumin loading in the NSB also resulted in higher antioxidant activity in aqueous media compared to the free curcumin. Formation of low crystallinity curcumin nanoparticles (CUR-NP) using a two-step process: In addition to the simultaneous process, a two-step process was developed to form CUR-NP. In this process, first NSB was formed from high amylose starch hydrogels via SC-CO2 drying, then, in the next step, curcumin was impregnated into the dry NSB using a SC-CO2 impregnation process. In this process, first a CUR-SC-CO2 solvato complex was formed, then this complex diffused into the nanopores of the NSB, and finally, the curcumin was precipitated from the solvato complex via rapid cooling. Impregnations were carried out at varying temperatures (40, 70, 95, and 120 °C) and 45 MPa, at a cooling rate of 5.5 °C. It was found that the impregnation capacity is limited by the solubility of CUR in SC-CO2 and also the volume of the vessel. Therefore, ethanol was used as a co-solvent (10-20% in SC-CO2), and an integrated successive cooling and dynamic flow process was used to improve mass transfer properties of the solvato complex and to repeatedly load curcumin from the solvato complex into the NSB. Impregnation capacity increased from 0.01 to 0.18 when the temperature increased from 40 to 70 °C with the static process. When the successive cooling & dynamic process was used at 70 °C, the impregnation capacity increased to 1.5% (8.3-fold increase), which proved that the process was solubility- and mass transfer-limited. Objective 3. Determine the stability, bioavailability, and bioactivity of CUR-NP against gut inflammation in vitro and in vivo. Storage stability of the CUR-NP: Light and temperature stability of the CUR-NP was tested with a 2-month storage test. CUR-NP samples in NSB and composite NSB (0.5 and 0.75 chitosan-modified) were stored at direct visible light exposure and in the dark at room temperature (25 °C) and 40 °C. There was no degradation in the CUR-NP in neat NSB and 0.5% chitosan-modified NSB after 2 months whereas there was up to 6% loss in the free curcumin at 25 °C. Degradation at 40 °C was significant for free curcumin and the chitosan-modified ones (up to 30% loss), however, there was no degradation in the CUR-NP impregnated in the neat NSB at 40 °C. In vitro bioaccessibility and stability of the CUR-NP in a real food product: The performance of the product was tested in a real food product, namely, yogurt, in terms of bioaccessibility and stability during storage. Bioaccessibility of the controls (free curcumin and free curcumin and NSB mix) in yogurt was 1.8% on Day 1, whereas it was 12% for the CUR-NP. On day 21, bioaccessibility of the CUR-NP in yogurt was 18%, showing that the product is stable in terms of bioaccessibility in a high water-content food product during storage (Fig. 3). Moreover, there was no significant degradation in our product in yogurt during 21 days of storage; however, 30% of both controls degraded in 21 days. The product also did not affect the water-holding capacity of the yogurt negatively. The product was also tested in granola bars as a solid low-water-content-food model. Early data have shown the superior performance of our product in granola bars in terms of bioacessibility and stability. Bioavailability and bioactivity of CUR-NP in human intestinal epithelial cells: Bioavailability of CUR-NP in Caco-2 cells: More curcumin was detected in the bottom (basolateral) chamber compared to free curcumin, suggesting CUR-NP was transported across the epithelium. The lower curcumin concentration in Caco-2 cells treated with CUR-NP (vs cells treated with free curcumin) suggests that Caco-2 cells metabolize and transport curcumin (in the form of CUR-NP) faster than it does free curcumin. The curcumin formulations did not negatively affect the viability of the Caco-2 cells. Bioactivity of CUR-NP in Caco-2 cells: Evaluation of mTORC1 activity: CUR-NP was more biologically active than free curcumin based on the inhibition of mTORC1 activity at the level of p70 S6 kinase (-61% vs control) and S6 ribosomal protein (-53% vs control) in Caco-2 cells. Bioactivity of CUR-NP in HT-29 cells: Evaluation of mTORC1 activity: CUR-NP was more biologically active than free curcumin based on the inhibition of mTORC1 activity at the level of p70 S6 kinase (-77% vs control) in HT-29 cells. Bioavailability of CUR-NP in animals: The bioavailability of CUR-NP was superior to that of free curcumin (6.6 folds increase) determined by a single oral dose of CUR-NP in rats. The glycemic response of the free curcumin and the CUR-NP was not different.

Publications

  • Type: Journal Articles Status: Published Year Published: 2023 Citation: Alavi, F. and Ciftci, O. N. (2023). Effect of starch type and chitosan supplementation on physicochemical properties, morphology, and oil structuring capacity of composite starch bioaerogels. Food Hydrocolloids, 141, 108637.
  • Type: Journal Articles Status: Under Review Year Published: 2023 Citation: Alavi, F. and Ciftci, O.N. (2023). Single-step simultaneous composite starch aerogel formation-high bioaccessibility curcumin particle formation. International Journal of Biological Macromolecules.
  • Type: Journal Articles Status: Submitted Year Published: 2023 Citation: Alavi, F. and Ciftci, O.N. (2023).Increasing bioavailability of curcumin using a green approach based on simultaneous starch aerogel formation-curcumin impregnation via supercritical fluid technology. Carbohydrate Polymers.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2022 Citation: Alavi, F., and Ciftci, O. N. Superlight, Macroporous Bioaerogels Produced From Cold-set Egg White Proteins Hydrogels Show Superior Oil Structuring Capacity. Institute of Food Technologists (IFT) Annual Meeting & Expo: Protein Division, July 10-13, 2022, Chicago, IL, USA.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2022 Citation: Alavi, F., and Ciftci, O. N. Formation of starch bioaerogels with superior oil structuring capacity: A new approach to developing saturated fat replacers. Conference of Food Engineering, September 18-21, 2022, Raleigh, NC, USA.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2022 Citation: Ciftci, O.N. A new and green particle formation approach to increasing bioavailability of curcumin. International Society for Nutraceuticals and Functional Foods, October 2-5, 2022, Istanbul, Turkey.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2023 Citation: Alavi, F., and Ciftci, O. N. Development of novel high bioavailability curcumin formulation using nanoporous starch bioaerogels. 19th European Meeting on Supercritical Fluids, May 21-24, 2023, Budapest, Hungary.
  • Type: Other Status: Accepted Year Published: 2023 Citation: Patent: Bioavailable Curcumin Nanoparticles and Methods of Making Patent No. 11,654,119


Progress 06/01/21 to 05/31/22

Outputs
Target Audience:Academy: Professors and research staff at both national and international academic institutions. Undergraduate and graduate students: Undergraduate and graduate students in the FDST 465/865 Food Engineering Unit Operations course taught by the PD Dr. Ciftci. Industry: Food and nutraceutical companies both in the U.S. and Europe. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?Similar to the previous period, aPhD student and a postdoctoral fellow was trained in supercritical fluid technology, bioavailability, bioaerogels, green food technologies, food engineering for human health, process design and advanced food analysis. The expertise in supercritical fluid technology in food processing in the U.S. is limited; therefore, training highly qualified personnel in this area is important for expanding green bioprocessing and bioengineering area in the U.S. The PD trained the PhD student and the postdoc on designing supercritical fluid systems, operating those systems, and their troubleshooting. Moreover, an extensive training on advanced food analyses was given to the PhD student. How have the results been disseminated to communities of interest? Manuscripts were published in scientific journals. Our project and findings were included in the undergraduate and graduate level FDST 465/865 Food Engineering Unit Operations course taught by the PD. The developed process and the bioaerogels were introduced to the food science students to show the role of food engineeirng in improving food quality, safety, and human health. The role of USDA in promoting food quality, safety, and human health via supporting research on developing novel foods and innovative food manufacturing technologies was demonstrated. The research lab of the PD was visited by scientists from food industry. The project and the novel food materials and technologies developed in this project were introduced to those scientists. Potential applications and commercialization potential of the products and the technologies were discussed. What do you plan to do during the next reporting period to accomplish the goals?We will continue Objective 2 and start the activities in Objective 3. In Objective 2, we will continue working on Method 1 for the formation of low crystallinity curcumin particles impregnated in the starch bioaerogels (CUR-NP)and up scaled process modeling and cost optimization.In Objective 3, we will work on incorporation of the CUR-NP into foods and their stability, micelle formation, bioavailability and bioactivity, and animal studies. We have discovered other exciting opportunities offered by this project; if time allows, we will perform experiments to explore other novel food materials and applications as well.

Impacts
What was accomplished under these goals? The long-term goal of this project is to develop simple, efficient, and green strategies to enhance the bioavailability of lipophilic bioactives. The main objective of this project is to develop an innovative and green particle formation technology to manufacture first-of-their-kind low-crystallinity bioactives with improved bioavailability. The specific objectives are: Design, fabricate, and characterize NSB, Reduce the size and crystallinity of CUR using NSB and SC-CO2, and Determine the stability, bioavailability, and bioactivity of CUR-NP against gut inflammation in vitro and in vivo. ?Effect of starch type and chitosan supplementation on the physicochemical, morphology, and oil structuring capacity of starch bioaerogels Effect of amylose and amylopectin content of the starch on the surface area and pore size of the nanoporous starch bioaerogel (NSB) was determined and the NSB were characterized in terms of morphology, pore size, surface area, and surface properties/chemistry. In addition, the new NSB were produced by chitosan addition. The starch hydrogel precursors were prepared from dent starch (27% amylose), 55% amylose, and 72% amylose starch in the presence of 0, 0.50, and 0.75 wt.% chitosan. The starch type showed a significant effect on the characteristics of resulting aerogels, where aerogels with higher content of amylose showed significantly lower shrinkage and density and higher specific surface area and macroporosity. Furthermore, chitosan addition substantially decreased the shrinkage of the aerogels, particularly those prepared with the dent starch, resulting in aerogels with lower density and higher specific surface area and macroporous volume. These aerogels were then employed as oil-absorbing porous templates for structuring liquid oils to form oleogels. Compared to the aerogels obtained from the dent starch, the aerogels from 55% amylose and 72% amylose starch showed greater oil structuring capacity. Furthermore, the starch aerogels supplemented with chitosan showed significantly higher oil structuring ability compared to the neat starch aerogel counterparts, where solid-like, plastic oleogels with strong elastic modules were developed when the composite starch/chitosan aerogels were used as a template. This work suggests that the starch type and the presence of chitosan had profound effects on the density and porosity of the starch aerogels and their oil structuring. Formation of low-crystallinity curcumin (CUR) nanoparticles impregnated in nanoporous starch bioaerogels (CUR-NP) using two novel methods Method 1: Impregnations were carried out in a SC-CO2 impregnation system that was designed and built in our lab. High pressure vessel of the SC-CO2 system was divided into two equal compartments by a sintered filter (0.22 μm). An excess amount of CUR (5 g) wasplaced into the bottom compartment, and 1 g of NSB monolith wasloaded into the top compartment. Impregnations weredone in semi-dynamic mode to improve the diffusion of the CUR-SC-CO2 solvato complex into the NSB matrix. The vessel was held at the set temperature and pressure for varying times (30 min-3 h). The vessel was cooled at varying cooling rates (0.6-10 °C/min) to control the precipitation of the CUR molecules in the NSB. The CUR -SC-CO2 solvato complexdiffused into the nanopores of the NSB andprecipitated in the nanopores when the temperaturedecreased below the supercritical temperature (31 °C) because the CO2 was notin the supercritical region anymore; therefore, solubility of the CUR in the SC-CO2decreased to zero. Different cooling rates wereused to determine the effect of precipitation routeof the CUR-SC-CO2 solvato complex on the phase diagram. Precipitation routes of supercritical-gas and supercritical-liquid-gas phase transitions wereused to explain the effect of cooling rate on the mechanisms of CUR-NP formation and crystallinity. Products were chracterized for CUR impregnation capacity, morphology, particle size, and crystallinity. Experiments on Method 1 continue. Method 2: A novel simultaneous NSB formation-CUR-NP formation process asdeveloped to form CUR-NP already impregnated in the NSB. Briefly, CUR wasdissolved in ethanol at room temperatureand 40-50 °C (to increase loading capacity as CUR has higher solubility in ethanol at higher temperature), and this ethanolic CUR solution wasused in the solvent exchange stepinstead of ethanol to form alcogel. Dissolved CUR-containing alcogels weredried with SC-CO2 at 40 °C and 10 MPa. At these conditions, CUR is not soluble in the SC-CO2 but ethanol is soluble. Therefore, SC-CO2acted as an antisolvent for the CUR. As a result, CURprecipitated in the NSB but ethanol wasdissolved in the SC-CO2 and removed by the SC-CO2. Effect of the CO2 flow rate (0.5-5 L/min, at ambient conditions) during SC-CO2 drying on the impregnation capacity, CUR-NP size, crystallinity, and CUR-NP distribution in the NSB were investigated. The products wereanalyzed and characterized for morphology, surface area, pore size, crystallinity, loading capacity, and interactionof CUR with NSB. Curcumin loading into NSB using ethanol as solvent: Experiment, mathematical modeling, and sensitivity analysis Loading capacity of NSB obtained fromstarch were first experimentally investigated, then, a comprehensive mathematical model was employed for CURloading into NSB based on mass conservation law. The model had two major parameters namely active porosity of the NSBand effective diffusion coefficient of CUR into the NSB, which were determined using loading capacity data together with empirical correlations. A step-by-step solution strategy was then provided to solve the model numerically using both finite difference method (FDM) and finite element method (FEM), and its accuracy was successfully confirmed against experimental data. Finally, a sensitivity analysis by the model showed that length per diameter ratio of the aerogel, and, more specifically, solution temperature and initial concentration of CUR in the solution were three of the most critical factors affecting the loading performance. The model also revealed that aerogel with rectangular shape gave the highest performance compared to cylindrical and spherical shapes.

Publications

  • Type: Journal Articles Status: Accepted Year Published: 2022 Citation: Alavi, F. and Ciftci, O. N. (2022). Superlight microporous aerogels produced from cold-set egg white protein hydrogels show superior oil structuring capacity. Food Hydrocolloids. In press.
  • Type: Journal Articles Status: Accepted Year Published: 2022 Citation: Alavi, F. and Ciftci, O. N. (2022). Developing dual nano/macroporous starch bioaerogels via emulsion templating and supercritical carbon dioxide drying. Carbohydrate Polymers. In press.
  • Type: Journal Articles Status: Submitted Year Published: 2022 Citation: Alavi, F. and Ciftci, O. N. (2022). Effect of starch type and chitosan supplementation on the physicochemical, morphology, and oil structuring capacity of starch bioaerogels. Food Hydrocolloids.


Progress 06/01/20 to 05/31/21

Outputs
Target Audience:Academy: Professors and research staff at both national and international academic institutions. Undergraduate and graduate students: Undergraduate and graduate students in the FDST 465/865 Food Engineering Unit Operations course taught by the PD Dr. Ciftci. Industry: Food and nutraceutical companies both in the U.S. and Europe. Changes/Problems:The publications were held on purpose due to patentability of the technoilogy and the products. Once we file the patent application on new bioaerogels, we will submit the manuscripts to journals. What opportunities for training and professional development has the project provided?A PhD student and a postdcotoral fellow was trained in supercritical fluid technology, bioavailability, bioaerogels, green food technologies, food engineering for human health, process design and advanced food analysis. The expertise in supercritical fluid technology in food processing in the U.S. is limited; therefore, training highly qualified personnel in this area is important for expanding supercritical fluid research in bioprocessing and bioengineering area in the U.S. The PD trained the PhD student and the postdoc on designing supercritical fluid systems, operating those systems, and their troubleshooting. Moreover, an extensive training on advanced food analyses was given to the PhD student. How have the results been disseminated to communities of interest? Manuscripts were prepared to be published in scientific journals. Our project and findings were included in the undergraduate and graduate level FDST 465/865 Food Engineering Unit Operations course taught by the PD. The developed process and the bioaerogels were introduced to the food science students to show the role of food engineeirng in improving food quality, safety, and human health. The role of USDA in promoting food quality, safety, and human health via supporting research on developing novel foods and innovative food manufacturing technologies was demonstrated. The PD introduced the project and shared the findings with professors, graduate and undergraduate students in the NC-1023 multi-institutional course/seminar series. This multi-institutional course provides a broad perspective of innovation as applied to food engineering. The course constitutes weekly presentations from 12 speakers on topics in three thematic areas: By-Product Utilization, Engineering for Health, and Engineering and Processing for Sustainable Systems. Twelve universities are concurrently offering this course in the spring semester/quarter of 2021 with > 100 students enrolled. The online platform has given unique opportunities for students to meet their peers and faculty from across the county, create a peer network of researchers and mentors to learn from their experiences and build a sense of community. The PD was approached by several food and nutraceutical companies both in the U.S. and Europe to get more information about the technology and the products generated by this technology. The PD had telemeetings with those companies to introduce this innovative technology. The readiness of the technology to transfer to industry was discussed. A seminar was given to PM International and the scientists at the Luxembourg Institute of Technology. Luxembourg Ministry of Economy attended PD's presentation during the award ceremony when the PD Dr. Ciftci received the LIST International Award for Bioinnovation for his work with this USDA-funded project. The PD Dr. Ciftci gave a talk on the project. This talk and the award ceremony was broadcasted on YouTube. Afterwards, a press conference was held by journalists to get more information about this technology. What do you plan to do during the next reporting period to accomplish the goals?No changes to the initial plan. We will continue Objective 2 and start the activities in Objective 3 in collaboration with the Co-PD Dr. Moreau. In Objective 2, we will continue working on formation of low crystallinity curcumin particles impregnated in the starch bioaerogels (CUR-NP) using two novel methods, mathematical modeling of the particle formation using SC-CO2, and up scaled process modleing and cost optimization. In Objective 3, we will work on incorporation of the CUR-NP into foods and their stability, micelle formation, bioavailability and bioactivity, and animal studies.

Impacts
What was accomplished under these goals? The potential health benefits of many lipophilic (water-insoluble) bioactives with disease-fighting potential are not fully realized due to their low bioavailability, which is caused by poor water solubility. Despite limited efficiency up to this point, lipophilic dietary bioactives hold great potential to combat diseases, as the increased prevalence of diet-related illnesses (e.g., gastrointestinal health problems, inflammation, cancer, and obesity) and the growing demand for "natural" and "clean" foods have negatively impacted the acceptability of foods containing artificial ingredients. In response, the food industry has placed a high priority on the development of foods that use bioactives. The incorporation of water-insoluble bioactives into foods, however, is a major challenge from a technological and food quality standpoint because they are generally crystalline powders that are insoluble in water and poorly soluble in fats and oils. Poor water solubility is a major factor accounting for the limited bioavailability of the bioactives. This is because as crystals, lipophilic bioactives are typically not water soluble, and thus poorly bioavailable; in contrast, amorphous forms are water-soluble and more bioavailable. Therefore, there is a critical need for a solution that decreases the crystallinity of crystalline water-insoluble bioactives and increases their solubilization in the digestive fluids. To fill this gap, we developed a simple, efficient, and green strategy to enhance the bioavailability of lipophilic bioactives. We developed an innovative and green particle formation technology to manufacture first-of-their-kind low-crystallinity bioactives with improved bioavailability. We use curcumin (CUR) as a model bioactive, because CUR is a lipophilic phenolic compound that attracted a lot of interest in food industry due to its health benefits. Low bioaccessibility of lipophilic phenolics in the aqueous phase of the intestinal content is responsible for their poor bioavailability. In the absence of methods to improve bioavailability of CUR, CUR's potential for efficiently improving human health will remain untapped. Initially, we designed, fabricated, and characterized nanoporous starch aerogels. We performed a detailed investigation of bioaerogel formation from starch,and later explored the potential to form novel bioaerogels from proteins. This new direction helped us open new avenues that will introduce other novel food products that will improve food quality and human health. The stach is a blueprint to apply to other biopolymers. When this innovative green technology and novel starch bioaerogels are transferred to food manufacturers, it will improve the health benefits of various food products, improve public health through simple diet; enhance the cost-benefit ratio of bioactives. The technology will reduce food wastes; avert toxic chemicals & environmental pollution; lower the costs of handling, storage & transportation of bioactives, because the product is a dry powder whereas most of the current lipophilic bioactive delivery systems are liquid. A patent application will be filed next year. Our accomplishments in Year 1 is summarized below: Objective 1. Design, Fabricate, and Characterize Nanoporous Starch Bioaerogel (NSB) Effect of amylose and amylopectin content of the starch on the properties of NSB & Characterization of the NSB. The effect of amylose and amylopectin content of the starch on the surface area and pore size of the NSB was determined and the NSB were characterized in terms of morphology, pore size, surface area, and surface properties/chemistry. In addition, the new NSB were produced by chitosan addition. The starch hydrogel precursors were prepared from dent starch (27% amylose), 55% amylose, and 72% amylose starch in the presence of 0, 0.50, and 0.75 wt.% chitosan. The starch type showed a significant effect on the characteristics of resulting bioaerogels, where bioaerogels with higher content of amylose showed significantly lower shrinkage and density and higher specific surface area and macroporosity. Furthermore, chitosan addition substantially decreased the shrinkage of the bioaerogels, particularly those prepared with the dent starch, resulting in bioaerogels with lower density and higher specific surface area and macroporous volume. These bioaerogels were then employed as oil-absorbing porous templates for structuring liquid oils to form oleogels. Oleogelation is a novel fat structuring method for converting liquid oils to solidified oil to reduce saturated fatty acids and trans-fatty acids in food products. The starch bioaerogels supplemented with chitosan showed significantly higher oil structuring ability compared to the neat starch bioaerogel counterparts, where solid-like, plastic oleogels with strong elastic modules were developed when the composite starch/chitosan bioaerogels were used as a template. This work suggests that the starch type and the presence of chitosan had profound effects on the density and porosity of the starch bioaerogels and their oil structuring properties. While working on Objective 1, we explored new directions on formation of bioaerogels that will help us further improve our international stature in bioaerogel formation. In addition to starch, we explored bioaerogel formation from proteins. Our accomplishments on the new projects are summarized below. 1. Developing dual nano/macroporous starch bioaerogels via emulsion templating and SC-CO2 drying. In this study, a new bioaerogel formation method was developed. Emulsified oil droplets were employed as a temporary porogen to obtain dual nano/macroporous starch bioaerogels by SC-CO2 drying. The effect of porogen content and starch concentration on physical and mechanical properties and the internal morphology of the obtained aerogels were studied. While the neat starch aerogel showed a compact structure in macroscale size with interconnected nanopores, the scarifying oil droplet porogens induced macropores in the emulsion-templated aerogels. Furthermore, the nanoporous structures of starch bioaerogels were also well-preserved in which the macropores were surrounded by fine and interconnected nanofibrous networks. It resulted in aerogels that exhibited internal morphology in two scales (macropores and nanopores) with a high surface area (156-190 m2/g). 2. Superlight macroporous bioaerogels produced from cold-set egg white proteins hydrogels show superior oil structuring capacity. In this study, a novel green cold gelation approach was developed to fabricate superlight macroporous bioaerogels from egg white protein (EWP). The cold-set hydrogels prepared by this method showed mechanical strength comparable to the heat-set hydrogels obtained by direct heating of EWP solution, but with much less biopolymer (protein) content. The hydrogels were then used to produce porous EWP bioaerogels by SC-CO2 drying. While bioaerogels obtained from the heat-set hydrogels showed a compact structure with high density and low macroporosity, the bioaerogels obtained from the cold-set hydrogels had 3-5 times lower density and significantly higher macroporous volume, due to the lower biopolymer concentration and less shrinkage of their precursor hydrogels. These bioaerogel scaffolds were then employed as templates for structuring a liquid oil. Compared to the bioaerogels obtained from the heat-set hydrogels, the bioaerogels from the cold-set hydrogels showed excellent oil structuring capacity, where solid-like, plastic oleogels with elastic module more than 2.0×105 Pa were developed.

Publications