Location: Methods and Application of Food Composition Laboratory
Project Number: 8040-52000-068-000-D
Project Type: In-House Appropriated
Start Date: Feb 20, 2019
End Date: Feb 19, 2024
Objective:
Objective 1. Determine the impact of industrial packaging methods (canning, freezing and drying) on the nutrients and bioactive compounds in fresh fruits and vegetables.
Objective 2. Validate a software program based on mathematical optimization techniques for estimating nutrient contents of commercial multi-ingredient foods.
Objective 3. Determine the impact of dietary fiber methodology on fiber composition and intake estimates.
Approach:
Objective 1. Industrial processing alters nutrients/bioactive compounds in fruits and vegetables. A 2-step, 2-year study for sample collection will be conducted. Consulting USDA plant scientists/other collaborators, multiple same-cultivar ripe samples will be collected simultaneously from one. Samples will be analyzed for vitamins, fiber, minerals, polyphenols, and metabolomics (baseline). Portions will be transported and stored to emulate typical commercial storage conditions; nutrients/polyphenols will be conducted in stored raw samples every 3 days until they decay. Shipping practices for samples will be simulated through collaborations with processing plants near harvest locations, emulating agricultural and industrial practices. Analyses at 0, 14, 35, 70, 120, 180 and 360 days post processing, and analysis in validated commercial laboratories, using AOAC methods, polyphenolic compounds analysis by ARS/academic collaborators will address the impact of processing.
Objective 2. Linear programming software for estimating missing nutrient values in commercially processed foods (using label values, ingredient lists) requires improved automation and analytical ingredient data. Food types (e.g., baked products) and nutrients will be identified, program functionality improvements completed, and tests, where ingredient proportions and nutrient values are known, will allow determination of estimation accuracy. The Virginia Tech (VT) Food Analysis Laboratory Control Center will prepare foods and QC materials for analysis; food manufacturers will be consulted on ingredient proportions, and an equivalence study of the estimates will be conducted to determine classes of nutrients and food types where the estimated and analytical values are similar, i.e. within ± 20%. Program validation will ensue to assess which nutrients to include.
Objective 3. The McCleary method (MCF) is a more complete determination of dietary fiber (DF) content in foods compared to the enzymatic-gravimetric (EGF) method, enabling better intake estimates. Select high-fiber foods and frequently consumed, fiber-containing foods will be analyzed by EGF (985.29) and MCF (2011.25) methods at a USDA-qualified commercial analytical lab. Foods with isolated or synthetic non-digestible carbohydrates may be analyzed. EGF (AOAC 985.29; total DF) and EGF (AOAC 991.43; soluble and insoluble DF), and MCF (AOAC 2009.01 and 2011.25 (fractions) will be studied and summed. Sumswill determine the food types where the fiber method used does not make a difference for measuring total DF. This allowsbetter understanding of the effect of fiber methodologies for selecting the appropriate analytical method for specific foods.
