ENHANCEMENT OF THE NUTRITIONAL AND FUNCTIONAL ATTRIBUTES OF NORTH DAKOTA PULSE CROPS

• Sponsoring Institution: National Institute of Food and Agriculture
• Project Status: COMPLETE
• Funding Source: HATCH
• Reporting Frequency: Annual
• Accession No.: 1012935
• Project Start Date: Oct 1, 2017
• Project End Date: Sep 30, 2022
• Program Code: [(N/A)]- (N/A)

Recipient Organization
NORTH DAKOTA STATE UNIV
1310 BOLLEY DR
FARGO,ND 58105-5750

Performing Department
Plant Sciences

Non Technical Summary
Pulse crops, including peas, dry beans and lentil, used to be obscure specialty crops with small market outlets in North Dakota. This situation has been changed in the recent years and pulse crops become one of the top agricultural products in North Dakota. The total market value of North Dakota produced pulse crops was $ 363 million in 2012. Nevertheless, the majority of North Dakota grown high quality pulse crops are exported with relatively low profits.The United Nations has designated 2016 as the International Year of Pulses due to the nutritional benefits and sustainable production. The heightened public awareness about the nutrient-dense pulse crops is expected to promote the consumption of pulses of all kinds in the United States. Moreover, the recent trend of incorporating healthy pulse constituents into other food products requires the food industry to mitigate their downside issues, such as "beany" flavors of pulse flour, low solubility of pulse proteins, and presence of antinutrients. This research attempts to solve the potential problems associated with current pulse ingredients and produce high valued functional food ingredients using North Dakota grown pulse crops. The proposed research will identify novel functional ingredients, such as natural antioxidants and improved pulse proteins through a simple bioprocessing technique germination. The research results will enable food companies to replace animal based food ingredients with pulse crops, resulting in foods with similar quality and enhanced human health properties. The outcomes will have a large economic impact on pulse production in North Dakota. The accomplishment of this project will serve as stepping stone for North Dakota to become a trusted provider of high quality agricultural products.

Animal Health Component

50%

Research Effort Categories

Basic

50%

Applied

50%

Developmental

0%

Classification

Knowledge Area (KA)	Subject of Investigation (SOI)	Field of Science (FOS)	Percent
501	1410	2000	100%

Knowledge Area
501 - New and Improved Food Processing Technologies;

Subject Of Investigation
1410 - Beans (dry);

Field Of Science
2000 - Chemistry;

Keywords

pulse

phenolic compounds

plant proteins

antioxidants

germination

Goals / Objectives
According to the latest news released from USDA National Agricultural Statistics Service, North Dakota ranks # 1 for production of more than 10 crops (NASS, 2016). Although the crops produced in North Dakota are a significant part of the state's economy, a high portion of the crops such as pulse crops are exported as raw materials for relatively low cash profits. In addition, the growing population has an increasing need for bioactive components and protein-rich ingredients in their diet. Such concerns are providing a renewed incentive for food scientists to explore value-added food ingredients from North Dakota pulse crops. Germination is a cheap and effective bioprocessing technique that has been known for centuries. Germination can effectively improve the nutritional value and quality of crops by improving their digestibility and increasing the load of bioactive compounds. The goal of this research is therefore to enhance the nutritional and functional attributes of ND pulse crops using germination. The following objectives will be investigated (i) Profiling the dynamic changes of minor constituents in North Dakota pulse crops during seed germination; (ii) Extraction, purification and characterization of proteins in North Dakota pulse crops during seed germination; (iii) Functionality of bioactive components and proteins in germinated seeds of North Dakota pulse crops.

Project Methods
The research target of this project includes lentil, chickpea and yellow pea are the commerical products of gifted from three North Dakota companies. Germinated pulse crops, including lentil, yellow pea, and chickpea containing the bioactive compounds will be prepared at NDSU. The resulting germinated pulses over the course of germination will be characterized with various analytics including phenolics, flavonoids, and oil soluble vitamins by HPLC-DAD, polar lipids by HPLC-ELSD, minerals by ICP-OES. The pulse proteins will be extracted and purified from germinated pulse crops at different processing time from defatted pulse flours. The molecular weight, surface charge, particle size, and thermal properties of purified plant proteins will be characterized by SDS-PAGE, Zetasizer, and DSC, respectively. The antioxidant ability of phenolic compounds and the functionality of proteins will be assessed using model food systems. Results will be analyzed and interpreted using statistical software packages. Evaluation will be based on (i) identifying the dynamic changes of minor components in pulse crops during the course of germination; (ii) unveiling the characteristics changes of proteins in pulse crops during the course of germination; and (iii) identifying the functionality of phenolic compounds and pulse proteins in food systems.

Progress 10/01/19 to 09/30/20

Outputs
Target Audience:The target audience during the reporting period including food and cereal researchers, graduate students, and food products and ingredients industry. Information was delivered through laboratory research, classroom instruction, short course, webinar, conference, and publications. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?This project has provided an opportunity for one Ph.D. student to improve their fundamental knowledge of food and cereal chemistry, food analysis, physicochemical and statistics sciences. How have the results been disseminated to communities of interest?The results have been published in peer reviewed journals and presented in multiple virtue conferences. What do you plan to do during the next reporting period to accomplish the goals?The next step in this work will be to extract the proteins from the germinated pulses and investigate the corresponding physical and chemical properties.

Impacts
What was accomplished under these goals? This year, we extracted pulse protein isolates (PPIs) from 0, 1, 3, and 5 days germinated chickpea, lentil, and yellow pea flours by alkaline extraction-isoelectric precipitation method. The impact of germination time had on the chemical proximate composition of PPIs was investigated. The aromatic profiles of the extracted PPIs were also determined using HS-SPME-GC-MS/O. The results showed that volatile compounds of PPIs extracted from pulse flours sharply diminished after extraction. Although nineteen new volatile compounds were developed during extraction, none of them contributed to the beany-related odor. Each pulse crop had their own characteristic volatile attributes deriving from pulse germination. PPIs extracted from pulse flours after a shorter germination time (1 day) slightly changed the volatile composition; however, their odors changed sharply along with longer germination time. Therefore, controlled germination conditions, such as germination time, substrates, environmental stress, and the addition of antioxidants might be possible measures for lowering the population of free radicals and further mitigating beany-related odor in germinated pulse proteins.

Publications

• Type: Journal Articles Status: Published Year Published: 2020 Citation: Minwei Xu, Jiajia Rao, Bingcan Chen. Phenolic compounds in germinated cereal and pulse seeds: classification, transformation, and metabolic process. Critical Reviews in Food Science and Nutrition, 2020, 60: 740-759
• Type: Journal Articles Status: Published Year Published: 2020 Citation: Minwei Xu, Zhao Jin, Zixuan Gu, Jiajia Rao, Bingcan Chen. Changes in odor characteristics of pulse protein isolates from germinated chickpea, lentil, and yellow pea: role of lipoxygenase and free radicals. Food Chemistry, 2020, 314: 126184

Progress 10/01/18 to 09/30/19

Outputs
Target Audience:The target audience during the reporting period including Food and cereal researchers, graduate students, and food products and ingredients industry. Information was delivered through laboratory research, classroom instruction, short course, conference, and publications. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?This project has provided an opportunity for one Ph.D. student to improve their fundamental knowledge of food and cereal chemistry, food analysis, physicochemical and statistics sciences. How have the results been disseminated to communities of interest?The results have been published in peer reviewed journals and presented in multiple international conferences. What do you plan to do during the next reporting period to accomplish the goals?The next step in this work will be to extract the proteins from the germinated pulses and investigate the corresponding physical and chemical properties.

Impacts
What was accomplished under these goals? Following previous year's study, we further investigated the effect of germination time on antioxidative activity and composition of yellow pea soluble free and polar soluble bound phenolic compounds. We found with the six days of germination, soluble free phenolic compounds and polar soluble bound phenolic compounds extracted from yellow peas had an opposite variation of antioxidative activity in SSO-in-water emulsion systems. The phenolic compositions of both types of phenolic compounds undoubtedly contribute to their antioxidative activity. The molecular weight is positively related to the antioxidative activity of polar soluble bound phenolic compounds. The synergistic effect between polar soluble bound phenolic compounds and their moieties is proposed to explain the variation of antioxidative activity following germination. Meanwhile, we also found the impact of germination on beany flavor development varied depending on the type of pulse seeds. Lentil and yellow pea flours had similar flavor with few differences during germination, while chickpea flours had different flavor attributes that became undesirable after four days of germination. The beany flavor associated volatile components increased in lentil and yellow pea flours over the course of germination, whereas beany flavors of chickpea decreased in conjunction with the increase of some unpleasant flavor notes.

Publications

• Type: Journal Articles Status: Published Year Published: 2019 Citation: Minwei Xu, Zhao Jin, Jae-Bom Ohm, Paul Schwarz, Jiajia Rao, Bingcan Chen. Germination Time and Composition Impact the Antioxidative Activity of Soluble Free and Polar Soluble Bound Phenolic Compounds from Yellow Pea. Food & Function, 2019, 10: 68406850.
• Type: Journal Articles Status: Published Year Published: 2019 Citation: Minwei Xu, Zhao Jin, Senay Simsek, Clifford Hall, Jiajia Rao, Bingcan Chen. Effect of Germination on the Chemical Composition, Thermal, and Pasting, and Moisture Sorption Properties of Flours from Chickpea, Lentil, and Yellow Pea. Food Chemistry, 2019, 291: 199206.
• Type: Journal Articles Status: Published Year Published: 2019 Citation: Minwei Xu, Jiajia Rao, Bingcan Chen. Phenolic Compounds in Germinated Cereal and Pulse Seeds: Classification, Transformation, and Metabolic Process. Critical Reviews in Food Science and Nutrition, 2019, DOI:10.1080/10408398.2018.1550051.
• Type: Journal Articles Status: Published Year Published: 2019 Citation: Minwei Xu, Zhao Jin, Yang Lan, Jiajia Rao, Bingcan Chen. HS-SPME-GC-MS/Olfactometry Combined with Chemometrics to Assess the Impact of Germination on Flavor Attributes of Chickpea, Lentil, and Yellow Pea Flours. Food Chemistry, 2019, 280: 8395.
• Type: Conference Papers and Presentations Status: Published Year Published: 2019 Citation: Minwei Xu, Bingcan Chen. Opposite antioxidative activity variation of soluble free and soluble bound phenolic compounds during yellow pea germination. 110 AOCS Conference, May 58, 2019, St. Louis, Missouri, USA.
• Type: Conference Papers and Presentations Status: Published Year Published: 2019 Citation: Minwei Xu, Bingcan Chen. Compositional Analysis of Flavor Attributes during Germination of Chickpea, Lentil, and Yellow Pea. IFT Annual meeting, June 25 2019, New Orleans, LA, USA.

Progress 10/01/17 to 09/30/18

Outputs
Target Audience:The target audience during the reporting period including Food and cereal researchers, graduate students, and food products and ingredients industry. Information was delivered through laboratory research, classroom instruction, conference, and publications. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?This project has provided an opportunity for one Ph.D. student to improve their fundamental knowledge of food and cereal chemistry, food analysis, physicochemical and statistics sciences. How have the results been disseminated to communities of interest?The results have been published in peer reviewed journals and presented atnational conferences. What do you plan to do during the next reporting period to accomplish the goals?The next step in this work will be to extract the proteins from the germinated pulses and investigate the corresponding physical and chemical properties.

Impacts
What was accomplished under these goals? We have completed the objective one "Profiling the dynamic changes of minor constituents in North Dakota pulse crops during seed germination". The composition of phenolic compounds in pulses including chickpea, lentil, and yellow pea, have changed after germination as evidenced by TPC value. Various pulse seeds demonstrated different trends on antioxidative activity of phenolic compounds during germination according to in vitro assay. Phenolic compounds extracts from germinated chickpea and yellow pea showed enhanced antioxidative activity while germinated lentil had poor improvement of antioxidative activity in an emulsion system. Soluble bound phenolic compounds had stronger antioxidative activity than free phenolic compounds in germinated chickpea and yellow pea, and they can be exploited as novel natural antioxidants. Synergistic effects between phenolic compounds and biopolymers they conjugated with may be attributed to their stronger antioxidative activity. We further characterized the phenolic compounds in chickpea during germination. We found compositions of soluble free and soluble bound phenolic compounds varied markedly during chickpea germination. Meanwhile, the molar masses of soluble bound phenolic compounds increased. These variations of phenolic compounds were responsible for the antioxidative activities in both in vitro assays and oil-in-water emulsions. The positive correlation between molar mass and antioxidative activity has profound guiding significance for improving the efficacy of natural antioxidants. Protective or dual antioxidative effects are speculated for the enhanced antioxidative activity of soluble bound phenolic compounds from chickpea after germination.

Publications

• Type: Journal Articles Status: Published Year Published: 2018 Citation: Minwei Xu, Zhao Jin, Jae Bom Ohm, Paul Schwarz, Jiajia Rao, Bingcan Chen*. 2018. Improvement of the Antioxidative Activity of Soluble Phenolic Compounds in Chickpea by Germination. Journal of Agricultural and Food Chemistry. 66(24): 6179-6187.
• Type: Journal Articles Status: Published Year Published: 2018 Citation: Minwei Xu, Zhao Jin, Allen Peckrul, Bingcan Chen*. 2018. Pulse Seed Germination Improves Antioxidative Activity of Phenolic Compounds in Stripped Soybean Oil-in-Water Emulsions. Food Chemistry, 250 (1):140-147
• Type: Book Chapters Status: Published Year Published: 2018 Citation: Bingcan Chen* and Minwei Xu. 2018. ⿿Natural Antioxidants in Food⿝. In ⿿Reference Module in Food Science⿝, Elsevier Inc.
• Type: Conference Papers and Presentations Status: Published Year Published: 2018 Citation: Minwei Xu, Bingcan Chen. 2018. The antioxidative activity of soluble bound phenolic compounds fractions extracted from germinated chickpea in oil-in-water emulsions. 109 AOCS Conference, May 6-9, 2018, Minneapolis, MN (Invited Talk).
• Type: Conference Papers and Presentations Status: Published Year Published: 2018 Citation: Fengchao Zha, Bingcan Chen. 2018. Physical and oxidative stability of O/W emulsions stabilized by gum arabic glycated pea proteins. 109 AOCS Conference, May 6-9, 2018, Minneapolis, MN.