Location: Market Quality and Handling Research2013 Annual Report
1a. Objectives (from AD-416):
1. Determine the effect of composition, maturity, moisture, handling, processing, and relevant interactions on flavor, shelf-life and texture characteristics in peanuts, peanut products, and related commodities. 2. Improve flavor and flavor consistency and reduce off-flavor potential in peanut varieties, breeding lines, germplasm and peanut products. 3. Extract, isolate, identify, and evaluate bioactive and/or biochemical components in peanuts, peanut products, and peanut plants that may exhibit nutraceutical properties, nutritional quality, biochemical and physical functionality or non-food biomass potential. 4. Examine the functional characteristics, value added potentials, and allergenic aspects of peanut protein and enzyme-produced peptides with a concentration on peanut meal resulting from commercial oil extraction processes. 5. Examine processing methods that result in improved peanut and almond ingredient food safety with minimum changes in flavor, shelf life, composition, and processing quality potentials.
1b. Approach (from AD-416):
Individual effects of maturity, composition, and moisture content of individual seed and how these factors interact during blanching and subseqent oil and dry roast processing will be examined in varieties and breeding lines of peanuts grown in the Uniform Peanut Performance Trials (UPPT) at several different locations. Peanut samples with high standard flavor profiles, unique flavor profiles, and peanuts subjected to various deviations in production, curing, and handling procedures will be evaluated for variations in components identifiable by GC, HPLC, and other chromatographic methods. Compunds associated with specific flavor characteristics unique in presence or magnitude will be isolated and identified by GC-MS or HPLC-MS. Newly developed microwave technology that provides uniform exposure to microwave energy will be utilized to study the effects of various time and power protocols on drying rate, flavor, and shelf-life of shelled and inshell peanuts.
3. Progress Report:
Roasted peanutty flavor volatiles were identified and verified in a model system. Samples from the Uniform Peanut Performance Trials from 6 locations were evaluated for flavor and composition in an ongoing program. Quality and flavor analysis of peanuts from 3 origins outside the US indicated increased production of high oleic peanuts in some foreign origins. Products developed from peanut skins using the procedure for spray drying peanut skin extracts developed by the Unit were evaluated for bioactivity in both chemical and cell based assays. Descriptive sensory analysis of the products was performed. Compounds present in the extracts responsible for the activity were identified. Peanut skins were used in studies which indicated that up to 5% skins could be added to peanut paste or peanut butter without negative flavor issues. Storage studies of peanut paste and peanut butter indicated that higher levels of skins resulted in eventual increase in peroxide values due to metals and low tocopherols in skin oil. Repeated studies of peanut and fat free peanut flour incorporated into a high fat high cholesterol diet consistently demonstrated reduced atherosclerosis in a hamster model. Further, peanuts and fat free peanut flour added to the diet of hamsters with diet induced elevated cholesteryl ester levels resulted in lowering of cholesteryl esters to pre-induction levels. In both studies, metabolomic data and gene activation data supported the findings and were related to more efficient cholesterol excretion and fatty acid metabolism and lowered inflammation markers. Systematic time /temp. roasting studies to optimize peanut quality were expanded to a pilot scale in cooperation with an industry partner. In cooperation with university coll., state of the art LC-MS analyses were used to describe the proteome of peanut skin versus corresponding seed providing basic information relevant to plant physiology, peanut agronomics and nutritional applications. A novel technology for processing aflatoxin contaminated peanut meal with bentonite clays and proteases to produce both isolated protein and peptides along with aflatoxin sequestered animal feed was demonstrated at a pilot plant level in cooperation with an industry partner. The potential of refractive index measurements to rapidly differentiate normal and high oleic peanuts was demonstrated. This method provides benefits in an industrial setting compared to traditional GC analysis for categorizing relevant seed fatty acid chemistry. Initial findings suggested a significant role of maturity in O/L ratio seed to seed variability in high oleic acid peanuts. The allergenic properties of enzymatically hydrolyzed peanut flour ingredients and peanut flour ingredients complexed with various fruit polyphenolics were documented in research with a university collaborators to optimize peanut flour for oral immunotherapy applications in treating peanut allergy. Continued temperature evaluation in peanut industry roasters indicated roaster function variability but, compared to published data, suggested sufficient temperature and time duration to reduce salmonella by industry required levels.
Jairam, S., Kolar, P., Sharma-Shivappa, R., Osborne, J., Davis, J.P. 2012. Kl-impregnated Oyster Shells as a Solid Catalyst for Soybean Oil Transesterificaton. Bioresource Technology. 104: 329-335.