Location: Healthy Processed Foods Research
2020 Annual Report
Objectives
Objective 1: Enable commercially-viable new technologies to detect and mitigate contaminants or defective products from food streams.
• Sub-objective 1A: Investigate x-ray as an alternative to gamma for food irradiation.
• Sub-objective 1B: Detect and mitigate fruit fly infestation in olives.
• Sub-objective 1C: Develop real-time non-destructive analysis of vanilla for adulteration.
Objective 2: Utilize advanced analytical and sensory methods to detect, identify, and quantify desirable and undesirable odors and taste defects in raw and processed foods.
• Sub-objective 2A: Identify compounds in raw and processed specialty crops including peas and grapes that impact flavor and taste. Identify precursors (and eventually pathways) of these compounds and study flavor variation in different varieties.
• Sub-objective 2B: Evaluate almond hulls for use in natural sweeteners or as a supplement to bee diets. Investigate the effects of almond hull phenolics on the acceptability of almond hull sugars in bee diets.
Objective 3: Develop commercially-marketable novel, value-added cereal-based healthy, tasty food products.
• Sub-objective 3A: Utilize oil seed (canola, sunflower and cotton) waste products to produce gluten-free, high protein flatbreads, snacks and pasta and evaluate for consumer acceptance.
Approach
1A: Baby spinach will be used to see if x-ray can replace gamma for food irradiation. The spinach will be inoculated with Shiga toxin-producing E. coli (STEC) strains and irradiated under x-ray and gamma irradiation. Pathogen populations will be monitored by plate count for differences between treatments of dose vs. population reduction. Should spinach not tolerate irradiation well a different commodity will be used. Other pathogens could also be studied, including Salmonella and Listeria.
1B: X-ray imaging and NIR spectroscopy will be evaluated for detection of olives infested with fruit flies. An olive fly colony will be established on-site for generation of infested samples. Film x-ray images will be acquired and digitized, and NIR spectra acquired. Chemometrics, neural network, discriminant analysis, and k nearest neighbor algorithms will be employed.
1C: NIR spectroscopy will be used to quantify coumarin and ethyl vanillin adulterations in vanilla extracts. Vanilla samples will be diluted using CMR, and NIR spectra obtained. Calibration equations for quantitative prediction will be developed. Collaborators will provide samples of vanilla extract processed using the method of green drying which bypasses the traditional curing process. NIR spectra will be acquired and calibrations developed to differentiate between vanilla extract processed under green drying vs. the traditional manner. Should the high ethanol and water concentrations in vanilla extract and concentrate make it impossible to obtain reliable calibrations, evaporation techniques will be developed to remove the ethanol and water and the remaining residue will be used to acquire spectra.
2A: Flavor compounds in peas and grapes will be quantified, precursors identified, and flavor variation studied between varieties. Pea protein will be produced from pea flour under spray drying and drum drying with different time and temperature conditions, and Grosch’s method of flavor analysis will be applied along with identification and quantification of saponins in pea flour and protein. GC-MS spectra will be matched to those in established libraries to identify food constituents. Aroma models will be compared with the food products by sensory panels.
2B: Sugars will be eluted from almond hulls using water and their composition determined by HPLC. Anthocyanins, flavonols, and hydroxycinnamates will be identified by comparison of retention times and UV/Vis spectra of unknown peaks with those of authentic standards. Weight and total phenolic content will be determined for each extract. Bee diet samples will be developed using a 25 °Brix solution of almond hull extract.
3A: Canola, sunflower and cotton seeds will be used to produce gluten-free products with high protein content and consumer acceptance. Various formulations of gluten-free cereal flours, seed meal vegetables and “condiments” will be used to produce pasta, snacks, and flatbread and presented to sensory panels. Proximate analysis will be applied to measure protein, fat, ash and moisture at each stage of processing. Those products that form crust (flatbreads and snacks) will be evaluated for acrylamide levels using LC-MS.
Progress Report
This project replaced project 2030-41430-001-00D, “Defining, Measuring, and Mitigating Attributes that Adversely Impact the Quality and Marketability of Foods,” which expired in July 2020.
In support of Sub-objective 1A, new x-ray tubes have been acquired that will allow more uniform and precise x-ray dosing of samples. The gamma irradiation unit at the collaborator’s facility is now fully functional. Sample preparation remains on hold until facility access is restored.
In support of Sub-objective 1B, infested olives have been acquired from local trees and a colony established. Preparation of an artificial diet based on published research is ongoing.
Accomplishments
