Location: Processed Foods Research
2011 Annual Report
• Sub-objective 1.1. Pinpoint and identify impact aroma compounds of raw materials and food products from legumes, almonds, grapes, olives, and wild rice using GC-Olfactometry (GC-O) and gas chromatography-mass spectrometry (GC-MS). Study flavor variation in different varieties (Takeoka). • Sub-objective 1.2. Isolate and characterize phytonutrients in raw materials and food products from legumes, almonds, grapes, olives, and wild rice. Determine the effects of processing on the levels of these constituents and also monitor changes in biological activity (i.e., antioxidant activity) (Takeoka, Berrios).
Objective 2: Add value to legumes, barley, rice, and potatoes and their fractions using extrusion, concentration and size reduction technologies to modify, control or enhance their nutritional, functional and sensory properties for the development of convenient and desirable gluten containing and gluten-free products with higher quality, shelf life and health benefits.
• Sub-objective 2.1. Develop healthy, nutritious, and convenient snack foods from legumes, barley, rice, wheat, apple, and potatoes, and their fractions using extrusion processing and forming technologies (Berrios, McHugh, Takeoka). • Sub-objective 2.2. Develop legume-based beverages formulated with conventional and non-conventional food ingredients, flours and protein powders from rice, wheat, and barley cooked by extrusion processing, drum drying, open kettle, pressure cooking, microwave cooking, and infrared cooking. The resulting cooked legume-based products in the form of powders will be used directly or pretreated by high pressure, microfluidizer processing, and high shear technology, as the base component for beverages with functional properties (Berrios).
This project involves the production of novel snack foods and beverages from legumes, barley, rice, potatoes and other agricultural products. The development of nutritious and tasty foods requires knowledge about the phytonutrients and flavor precursors present in the raw materials. The effects of processing on phytonutrient and flavor concentrations will be studied and processing parameters will be optimized to preserve these constituents. The scientists on this project have expertise in their respective areas and will work closely to achieve the objectives.
Colored potatoes (Solanum tuberosum L.) are a significant source of antioxidants from polyphenols, carotenoids and ascorbic acid. In this study, the retention of total antioxidants in fresh colored potatoes and processed potato flakes prepared as potential ingredients for snack foods was studied. Total antioxidant capacity, total phenolics and total anthocyanins were higher in purple potato flesh compared with those from red, yellow and white potato cultivars. Peeled purple potatoes were blanched and dehydrated by freeze drying (FD), drum drying and refractive window drying to prepare potato flakes. No significant losses in total antioxidant capacity and total phenolic content in flakes were observed with all drying methods studied. However, 45, 41 and 23% losses in total anthocyanins were observed in potato flakes after FD, drum drying and refractive window drying, respectively. Colored potatoes could provide an excellent source of antioxidant-rich ingredients for the production of nutritionally enhanced food products.
Foods with antioxidant capacity provide protection against certain forms of cancers, cardiovascular and Alzheimer’s diseases caused by oxidative damages and contribute health benefits. The effect of extrusion cooking on the antioxidant capacity and color attributes of extruded products prepared from three selected formulations of purple potato and yellow pea flours using a co-rotating twin screw extruder were studied. The total antioxidant capacities (TAC) of the extruded products were not significantly different (p < 0.05) from their respective raw formulations. The total phenolic contents (TP) of the extruded products varied from 2088 to 3766 µg of gallic acid equivalents/g dry weight sample and retained 73 – 83 % of TP from the raw formulations after extrusion. Compared with their raw formulations, significant losses (60–70%) of the total anthocyanins contents (TA) in the extruded products occurred during extrusion cooking. However, extrusion cooking retained antioxidant capacities of the raw formulations in the extruded products. This study demonstrated the potential for the production of puffed extruded food products with improved antioxidant content from colored potatoes and pulse formulations.
The flavors of bread, popcorn, aromatic rice (such as Basmati and jasmine), and tortillas are among the most popular and desirable of all foods. The appealing and attractive flavors of these foods are largely due to 2-acetyl-1-pyrroline and 2-acetyltetrahydropyridine. These two compounds have popcorn-like, cracker-like and roasty odors and are key contributors to the flavors of cereal products. In this study we synthesized and characterized a new flavor compound, 2-formyl-1,4,5,6-tetrahydropyridine. This compound has a pleasant cracker-like odor. Further studies are needed to determine if this compound occurs in food and, if so, to quantify its odor contribution.
Cool, L.G., Takeoka, G.R., Vermillion, K. 2011. Volatile non-terpenoid hydrocarbons from Ligusticum grayi roots. Phytochemistry Letters. 4:158-160.
Cui, L., Pan, Z., Yue, T., Atungulu, G.G., Berrios, J.D. 2010. Effect of ultrasonic treatment of brown rice at different temperatures on cooking properties and quality. Cereal Chemistry. 87(5):403-408. doi: 10.1094/CCHEM-02-10-0034.
Berrios, J.D. 2010. Extrusion cooking: Legume pulses. In: Helman, D.R., Moraru, C.I., editors. Encyclopedia of Agricultural, Food, and Biological Engineering. 2nd edition. New York, NY: Taylor & Francis Group. p. 453-464.