Performing Department
(N/A)
Non Technical Summary
Oilseed-derived meals are byproducts of the seed oil extraction process. Certain oilseed meals, such as sunflower meal, have the potential to serve as economically viable protein sources with minimal allergenic properties. However, these oilseed meals are often underutilized as protein sources due to their lower nutritional, functional, and sensory qualities, leading to undesirable taste and appearance. Plant proteins have been demonstrated to bind to antioxidant polyphenol compounds, which can affect the proteins' properties. The primary goal of this research is to examine the impact of protein-polyphenol interactions on the structure, functional properties, and nutritional value of oilseed protein isolates. By investigating and controlling these interactions, we aim to enhance the overall quality of sunflower protein isolates and concentrates. The modulation of sunflower protein-polyphenol interactions will be accomplished using chemical and enzymatic approaches. We will then incorporate the oilseed protein powders into baked products and different food model systems such as emulsions and gels to determine how modification of the proteins enhances the quality of the food products. The study will further investigate the effect of polyphenol type and concentration and the modified proteins on the formation of Advanced Glycation End-Products (AGEs), which are a diverse group of compounds produced during high-temperature food processes like baking. These AGE compounds have been linked to many age-related chronic diseases. Our research findings will help further the goals of NIFA program code A1364 by expanding our understanding of plant proteins' chemical, physical, and nutritional properties. Additionally, this project will drive innovation in the alternative protein sector by producing new, high-quality ingredients and products. Ultimately, this will enable the upcycling of oilseed byproducts that are currently not fully utilized in the food and beverage industry.
Animal Health Component
80%
Research Effort Categories
Basic
20%
Applied
80%
Developmental
(N/A)
Goals / Objectives
The overarching goal of this project is to develop oil seed meal proteins with improved nutrition and functional quality for use in the food industry. This will be achieved by controlling the interactions between proteins and polyphenol compounds during protein isolation. The project will be structured around three specific objectives aimed at fulfilling this overarching goal:1. Modify oilseed meal protein isolates by controlling polyphenol-protein conjugation with (a) thiol addition and (b) hydrolysis of polyphenols with esterase enzymes.· This objective aims to systematically examine the interactions between proteins and polyphenols in oilseed meals for application in the food industry. We will use chemical and enzymatic approaches to modulate the degree of protein-polyphenol interactions and characterize the structure of the conjugates. We will apply response surface methods to optimize the concentration of thiol and pH needed to achieve various levels of conjugation with sunflower proteins.2. Evaluate changes in the structure and functionality of oilseed proteins modified by protein-polyphenol conjugation.· This research objective will determine how modification of oilseed protein by polyphenol-protein impacts protein yield, purity, and functional properties like solubility, emulsifying capacity, and foaming ability. This study will also incorporate these protein isolates to assess their performance in different applications by producing baked products and food model systems such as emulsions and gels. Results from this work will provide valuable insights on how these isolates can enhance food products.3. Elucidate the formation of advanced glycation end products (AGEs) in sunflower protein isolates and baked foods formulated by incorporating sunflower proteins with varying extents of protein-polyphenol and protein-thiol conjugation.· This final objective will further investigate the impact of modified oilseed protein isolates on the formation of Advanced Glycation End-Products (AGEs) formed during the Maillard reactions. These reactions occur during food processing, where reducing sugars react with proteins, lipids, or nucleic acids. The presence of these compounds in food is a critical issue as they have been linked to several chronic diseases.
Project Methods
Protein-polyphenol interactions will be modified using two approaches. In the first approach, interactions between polyphenols and proteins will be modulated by addition of thiols which compete with polyphenols in binding with proteins. The second approach will involve the de-esterification of polyphenols in the seed meal to determine how different types of polyphenols interact with the protein. The concentration of thiols and enzymes, along with pH will be optimized using response surface methods (RSM).The de-esterifaction of the protein will done by utilizing a CGA-esterase (CE) derived from L. helveticus based on methods described in Lo Verde et al. (2022). UV-Vis spectroscopy and high-performance liquid chromatography (HPLC), and LC-MS will be used to monitor the types and concentrations of phenolic compounds in the seed meal proteins that have been isolated using alkaline extraction-isoelectric precipitation (AE-IEP) and then lyophilized for structural and functional analysis.To evaluate the structural and functional properties of the modified proteins, we will employ methods such as SDS-PAGE, Q-TOF LC/MS, Fourier transform infrared (FTIR) spectroscopy, Fluorescence, Differential Scanning Calorimetry (DSC), and Scanning Electron Microscopy (SEM). The functional properties to be assessed include protein solubility, emulsification, and gelling properties. Antioxidant properties will be assessed using various hydrogen atom and single electron transfer methods. Model baked food products will be developed with the modified protein to demonstrate the effect of protein-polyphenol conjugation on the improvement of nutritional and functional properties of food.To further support the food application of oilseed meal protein isolates modified by protein-polyphenol conjugation, we will investigate the formation of Advanced Glycation End products (AGEs), we will analyze both fluorescent AGEs in the seed protein isolates and their food models by fluorescence spectroscopy while non-fluorescent AGEs, such as CML and CEL, will be analyzed using UHPLC-Q-TOF-MS.Efforts to change actions, knowledge, and conditions: Undergraduate and graduate researchers: Carrying out the methods described above will involve training 1-3 undergraduate students and 1-2 graduate students. The students will be working on most parts of the proposal, including hands-on experimental work, experimental design, data analysis, and dissemination of the results.The general food science students in Southern California will be exposed to findings stemming from this work in the annual research showcase where we will share findings.Evaluation of output/outcomes: The ultimate goal is to determine how phenolic protein conjugates from the engineered Chlorogenic acid esterase and thiols affects functionality and AGE formation. This will enable us to obtain a comprehensive understanding of the protein-phenolic complexes, and how thiol and enzymatic treatment alters complex formation. The evaluation will be based on RSM design and analytical methods described in the approach section. The outcomes of the functional properties' studies will enable us to control the degree of conjugation to target various food and beverage applications. Technical success criteria for the last objective will be assessed by comparing the de-colorization strategies and degree of conjugation that result in the lowest AGE formation.Students conducting the work for their research credits will be evaluated based on program student learning goals to measure specific scientific skills, including the ability to design experiments, data analysis and critical thinking and technical communication.