Source: SOUTH DAKOTA STATE UNIVERSITY submitted to
SOY PHYTOCHEMICALS: CHEMISTRY, ANALYSIS, PROCESSING AND HEALTH IMPACTS
Sponsoring Institution
National Institute of Food and Agriculture
Project Status
TERMINATED
Funding Source
Reporting Frequency
Annual
Accession No.
0194030
Grant No.
(N/A)
Project No.
SD00202-H
Proposal No.
(N/A)
Multistate No.
(N/A)
Program Code
(N/A)
Project Start Date
Oct 1, 2002
Project End Date
Sep 30, 2008
Grant Year
(N/A)
Project Director
Wang, C. Y.
Recipient Organization
SOUTH DAKOTA STATE UNIVERSITY
PO BOX 2275A
BROOKINGS,SD 57007
Performing Department
College of Education & Human Sciences
Non Technical Summary
Phytochemicals are defined as minor non-nutritive components from plants. Soy phytochemicals, including isoflavones, saponins, phytates, phytosterols, and tocols, play major roles in chronical disease prevention. The proposed study will address chemistry, analysis, presence, processing and potential health impacts of these phytochemicals.
Animal Health Component
(N/A)
Research Effort Categories
Basic
30%
Applied
40%
Developmental
30%
Classification

Knowledge Area (KA)Subject of Investigation (SOI)Field of Science (FOS)Percent
5011820200030%
5011820202020%
7011820200040%
7011820202010%
Goals / Objectives
The long-term goal of the proposed study is to generate new knowledge and develop new technologies concerning phytochemicals in soybeans. Specific objectives are to develop analytical techniques for phytochemicals in soybeans, including isoflavones, saponins, phytates, phytosterols, tocols; to utilize developed method in investigating the genetic and environmental factors influencing concentrations of these phytochemicals; to study the effects of processing on retention of phytochemicals and to develop new processing techniques that would maintain health benefits of whole soybeans; and to conduct preliminary experiments in soy phytochemicals to gain external funding.
Project Methods
Unique HPLC methods will be developed for soy phytochemcals. Factors affecting phytochemical concentrations in soybeans will be investigated by studying samples from different growing locations, crop years, and cultivation practices. The effects of soy ingredients (soy oil, soy protein concentrates, and soy protein isolates) processing will also be studied by conducting mass balance. Alternate processing techniques and conditions will be developed to retain higher concentrations of phytochemicals.

Progress 10/01/02 to 09/30/08

Outputs
OUTPUTS: During the past six years, very significant amount of new knowledge was discovered through this project. 1. The new procedure for the determination of soyasaponin Bs in soybeans using HPLC/ELSD was developed. The quantification method was rapid, practical, and accurate in analyzing the three major non - DDMP soyasaponin Bs and five DDMP soyasaponin Bs. The sample preparation of this method was simple and took less time than existing methods. 2. Another procedure for the simultaneous determination of isoflavones and soyasaponins B in soybeans using HPLC/UV/ELSD was also developed. The quantification method was rapid, practical, and accurate. Twelve isoflavones, three major non DDMP-conjugated soyasaponins B, and five DDMP-conjugated soyasaponins B were quantified. The method of sample preparation required significantly less time than other published methods. 3. The mass balance of isoflavones and saponins during manufacturing of soy protein isolate were also studied. The study revealed that only about 29% and 14% of the total isoflavones and saponins in soy flour remained in soy protein isolate, respectively. The isoflavone and saponin profiles of the soy protein isolate were very different from that of soy flour. 4. The effects of refining steps on the retention of tocopherols and phytosterols were studied. The whole refining process reduced the total tocopherols by 32.6%. The whole refining process reduced the total phytosterols by 24.5%. 5. An innovative approach was for estimating flavonoids intake of Americans and establishing potential relationships between flavonoids intake and certain health outcomes. The resulting data showed that the overall average intake of flavonoids for the 4,534 individuals that completed the What We Eat in America 2001-2002 survey was 21.88mg. The average intakes of the flavonoid subclasses were also calculated, with the intake of flavan-3-ols being the highest at 72.43mg. Flavonol intake was 22.42mg, flavones was 8.59mg, flavanones were 4.33mg and the anthocyanidin subclass had the lowest intake of 1.63mg. Furthermore, when all the individuals were combined in the analysis, the results indicated that there was significance positive correlation between flavanoids intake and both total cholesterol (p=.0057) and LDL cholesterol (p=.0377). It is not known why these correlations exist. Other statistical analyses are being conducted to confirm or explain the discovery. 6. Further study reveals very significant and interesting correlations between consumption of specific flavonoids and several health outcomes. Examples include cyanidin and blood pressure; cyanidin and diabetes; obesity and Theaflavi3-3 digallate; luteon and cancers; catechin and LDL Cholestrol and etc. 7. A special study was conducted on the VitaCow system for producing soymilk. The system produces soymilk with very different phytochemical and flavor profile. The difference in the photochemical profile (distribution of isoflavones) can be the major cause of the difference in the flavor profile. VitaCow system produced soymilk with better flavor scores (more acceptable), compared to the soymilk produce with traditional method. PARTICIPANTS: PIs and about 5 graduate students and 2 research associates. TARGET AUDIENCES: The target audiences include the food industry, the public on health information, fellow food nutrition and biomedical researchers, and decision makers for health research fundings. PROJECT MODIFICATIONS: Not relevant to this project.

Impacts
This research on phytochemicals in soybeans benefited soybean producers by increasing the awareness of health benefits of soy foods. It also benefited the general public and the soy processing industry through new knowledge about phytochemicals and processing techniques. Our study on flavonoids will provide very important foundation for further biomedical research and will also help funding agencies to target their investment in only promosing natural compounds.

Publications

  • Sonee, M., T. Sum, C. Wang, and S. Mukherjee. 2003. The Soy Isoflavone, Genistein, Protects Human Cortical Neuronal Cells form Oxidative Stress. Neuro Toxicology 25 : 885-891
  • Wang, C. and M. Self. 2003. Alternative Analytical Methods for Soy Isoflavones. JAOCS. In Revision. SD Agricultural Experiment Station Journal Article No. 3036
  • Wang, C. 2004. Effects of Processing on Soy Isoflavones. INFORM, 15 (1): 16-19


Progress 01/01/07 to 12/31/07

Outputs
OUTPUTS: During this reporting period, we have focused our effort on studying a processing system named VitaCow it impacts on flavor quality of soymilk and it phytochemical profile. VitaCow is a system designed to produce soymilk and other products. This system is known to produce soymilk with lower level of beany flavor due to oxygen limitation during the grinding step. The system also cooks the soymilk under pressure and shortens the cooking time. The objective of the study was to investigate the effects of processing conditions (100oC, 110oC, 120oC, 130oC) on the yield, protein recovery, sensory and physio-chemical properties of soymilk. Yield and protein recovery were calculated based on the percentage of solid protein recovered in the soymilk products. The products were evaluated by a taste panel on their color, mouthfeel, flavor, and preference. Viscosity and color were evaluated instrumentally. Peroxide value and conjugated dienoic value were also used to measure the degree of lipid oxidation in the product. This work will be presented in July at the Institute of Food Technologists. PARTICIPANTS: Dr. Zhien Ding, Visiting Professor From China Ms. Vandana Panchel, Graduate Students This project has been crucial in collaborating with a scientist form China and traing graduate and undergraduate students.

Impacts
The study showed that the VitaCow system produced soymilk products with better yield and protein recovery. Soymilk when processed with VitaCow at 100oC produced soymilk with 20% better yield and higher protein recovery when compared to traditional processing method. When the processing temperature was 120oC and 130oC the yield and protein recovery were about the same as of traditional method due to protein denaturation. Soymilk produced with VitaCow at 100oC and 110oC had light creamy color, less beany flavor and had higher preference than that produced with traditional method. Overall soymilk produced by VitaCow had much higher viscosity. Due to the high temperature with the VitaCow System the profile for isoflavones and saponins were significantly different then the soymilk produced traditionally. However the total aglycone equivalent did not changed significantly. This research on phytochemicals in soybeans benefited soybean producers by increasing the awareness of health benefits of soy foods. It also benefited the general public and the soy processing industry through new knowledge about phytochemicals and processing techniques. This work with VitaCow will not only help us to develop an alternate way of processing soymilk, it will also help us understand the baic mechanism of off-flavor formation and the roles of phytochemicals in mangament of flavors.

Publications

  • No publications reported this period


Progress 01/01/06 to 12/31/06

Outputs
During the current reporting period, major efforts were still in estimating flavonoids (soybeans contain a major subclass of these: isoflavones) intake of Americans and establishing potential relationships between flavonoids intake and certain health outcomes. The National Health and Nutrition Examination Survey (NHANES) food intake database and the USDA phytochemical database were combined to accomplish our objectives. The resulting data showed that the overall average intake of flavonoids for the 4,534 individuals that completed the What We Eat in America 2001-2002 survey was 105 mg. The majority of individuals (86.97%) consumed low amounts of flavonoids in the range of 0-150mg/day. This data may be inexact due to the small number of food samples with flavonoid concentrations that were included in the databases. However, this information can be incorporated into further studies as the flavonoid databases are expanded. After determining flavonoid intakes and trying to establish correlations between cardiovascular health indicators, it was difficult to be certain whether the results were actually based on the given factors. The results indicated that there was not a difference in intake levels based on gender or based on diabetes status. However, there was a significant difference in cholesterol levels based on both gender as well as diabetes status. Since cholesterol levels are impacted by both controllable and uncontrollable factors, a multiple regression model was needed to determine which factors predicted the greatest amount of variation. These results indicated that intake, age and gender together yielded the model with the most explained variation, showing evidence that in this case intake alone is insufficient at explaining a large extent of the variation in cholesterol levels.

Impacts
This research on phytochemicals in soybeans benefited soybean producers by increasing the awareness of health benefits of soy foods. It also benefited the general public and the soy processing industry through new knowledge about phytochemicals and processing techniques.

Publications

  • No publications reported this period


Progress 01/01/05 to 12/31/05

Outputs
The long-term goal of the proposed study is to generate new knowledge and develop new technologies concerning phytochemicals in soybeans. Specific objectives are: (1) to develop analytical techniques for phytochemicals in soybeans, including isoflavones, saponins, phytates, phytosterols, tocols; (2) to utilize developed method in investigating the genetic and environmental factors influencing concentrations of these phytochemicals; (3) to study the effects of processing on retention of phytochemicals and to develop new processing techniques that would maintain health benefits of whole soybeans; (4) to conduct preliminary experiments in soy phytochemicals to gain external funding. Significance progress was accomplished in this third year of the project. During the current reporting period, major efforts was a innovative approach for estimating flavonoids intake of Americans and establishing potential relationships between flavonoids intake and certain health outcomes. The National Health and Nutrition Examination Survey (NHANES) food intake database and the USDA phytochemical database were combined to accomplish our objectives. The resulting data showed that the overall average intake of flavonoids for the 4,534 individuals that completed the What We Eat in America 2001-2002 survey was 21.88mg. The average intakes of the flavonoid subclasses were also calculated, with the intake of flavan-3-ols being the highest at 72.43mg. Flavonol intake was 22.42mg, flavones was 8.59mg, flavanones were 4.33mg and the anthocyanidin subclass had the lowest intake of 1.63mg. Furthermore, when all the individuals were combined in the analysis, the results indicated that there was significance positive correlation between flavanoids intake and both total cholesterol (p=.0057) and LDL cholesterol (p=.0377). It is not known why these correlations exist. Other statistical analyses are being conducted to confirm or explain the discovery.

Impacts
This research on phytochemicals in soybeans benefited soybean producers by increasing the awareness of health benefits of soy foods. It also benefited the general public and the soy processing industry through new knowledge about phytochemicals and processing techniques.

Publications

  • 1. Lin, J., P. Krishnan and Wang, C. 2006. Isoflavones and Saponins in Soy Protein Isolates JOACS 83 (1) 59-63.
  • 2. Lin, J., D. Mathees and Wang, C. 2006. Simultaneous Analysis of Isoflavones and Saponins JOACS (in review)


Progress 01/01/04 to 12/31/04

Outputs
The long-term goal of the proposed study is to generate new knowledge and develop new technologies concerning phytochemicals in soybeans. Specific objectives are: (1) to develop analytical techniques for phytochemicals in soybeans, including isoflavones, saponins, phytates, phytosterols, tocols; (2) to utilize developed method in investigating the genetic and environmental factors influencing concentrations of these phytochemicals; (3) to study the effects of processing on retention of phytochemicals and to develop new processing techniques that would maintain health benefits of whole soybeans; (4) to conduct preliminary experiments in soy phytochemicals to gain external funding. Significance progress was accomplished in this second year of the project. First, the effects of processing conditions on the retention of isoflavones and saponins during processing of soy protein isolates were further studied based on findings from last year. Conditions were achieved to increase there retention rate of isoflavones by 70%. Secondly, the effects of refining steps on the retention of tocopherols and phytosterols were studied. Tocopherols and phytosterols from different streams during soybean oil refining were measured by HPLC/UV and HPLC/ELSD, respectively. The content of tocopherols and phytosterols was not significantly different in degummed and alkaline-refined oil comparing to crude oil. The bleaching step reduced the total tocopherols by 27.9%, and the deodorization step further reduced the total tocopherols by 6.5%. The whole refining process reduced the total tocopherols by 32.6%. The bleaching step reduced the total phytosterols by 21.0%, and the deodorization step reduced the total tocopherols by an additional 4.4%. The whole refining process reduced the total phytosterols by 24.5%. Finally, analytical techniques developed in this project were also used in assessing processing's effects on corn products.

Impacts
This research on phytochemicals in soybeans benefited soybean producers by increasing the awareness of health benefits of soy foods. It also benefited the general public and the soy processing industry through new knowledge about phytochemicals and processing techniques.

Publications

  • Lin, J. and Wang, C. 2004. An Analytical Method for Soy Saponins by HPLC/ELSD. J. of Food Science 69 (6) C456-CC462. .
  • Lin, J. and Wang, C. 2004. Saponins: Chemistry, Analysis, Processing and Potential Health Benefits of Soyasaponins. In Soybeans as a Functional Food. A book edited by K. Liu and published by AOCS Press, Champaign, IL.
  • Mebrahtu, T., Mohamed, A., Wang, C.Y., and Andebrhan. 2004. Analysis of Isoflavone Contents in Vegetable Soybeans. Plant Foods for Human Nutrition 59: 55- 61, 2004.


Progress 01/01/03 to 12/31/03

Outputs
The long-term goal of the proposed study is to generate new knowledge and develop new technologies concerning phytochemicals in soybeans. Specific objectives are: (1) to develop analytical techniques for phytochemicals in soybeans, including isoflavones, saponins, phytates, phytosterols, tocols; (2) to utilize developed method in investigating the genetic and environmental factors influencing concentrations of these phytochemicals; (3) to study the effects of processing on retention of phytochemicals and to develop new processing techniques that would maintain health benefits of whole soybeans; (4) to conduct preliminary experiments in soy phytochemicals to gain external funding. Significance progress was accomplished in this first year of the project. First, the new procedure for the determination of soyasaponin Bs in soybeans using HPLC/ELSD was developed. The quantification method was rapid, practical, and accurate in analyzing the three major non - DDMP soyasaponin Bs and five DDMP soyasaponin Bs. The sample preparation of this method was simple and took less time than existing methods. The intra-days assay Coefficient of Variance (CV) was less than 9.51%, and inter-days assay CV was less than 10.91%, showing good precision. The recovery study using soyasaponin I and II was performed to evaluate the accuracy. Their percentages of recovery were 98.4% and 93.8%, respectively. Secondly, another procedure for the simultaneous determination of isoflavones and soyasaponins B in soybeans using HPLC/UV/ELSD was also developed. The quantification method was rapid, practical, and accurate. Twelve isoflavones, three major non DDMP-conjugated soyasaponins B, and five DDMP-conjugated soyasaponins B were quantified. The method of sample preparation required significantly less time than other published methods. The results have shown that the soyasaponins B concentration and composition varied in different varieties of soybeans, the isoflavone concentration and composition varied in different varieties of soybeans, and there was no relationship between the isoflavone content and the saponin content in soybeans. Thirdly, the mass balance of isoflavones and saponins during manufacturing of soy protein isolate were also studied. The study revealed that only about 29% and 14% of the total isoflavones and saponins in soy flour remained in soy protein isolate, respectively. The isoflavone and saponin profiles of the soy protein isolate were very different from that of soy flour. For isoflavones, SPI had much more aglycones (genistein, glycitein, and daidzein) comparing with soy flour. Solid waste and solid water caused the most severe isoflavone loss. For saponins, SPI had much more non-DDMP saponins (V, I, and II) comparing with soy flour. Solid waste caused the most severe saponin loss. A patent is sought for a process of producing SPI with high concentrations of saponins and isoflavones.

Impacts
This research on phytochemicals in soybeans benefited soybean producers by increasing the awareness of health benefits of soy foods. It also benefited the general public and the soy processing industry through new knowledge about phytochemicals and processing techniques.

Publications

  • Wang, C., Johnson, L.A. and Wilson. 2003. L.A. Calcium Coagulation Properties of Hydrothermally Processed Soymilk. JAOCS, Vol. 80, no. 12.
  • Wang, C. 2003. Effects of Processing on Soy Isoflavones. INFORM, In Press
  • Lin, J. and Wang, C. 2003. An Analytical Method for Soy Saponins by HPLC/ELSD. J. of Food Science. In Revision.