Evaluation of Foods Processed in Tray Pack versus Two Standard Food Service Containers. Part 1. Sensory, Container and Bacteriological Tests

摘要

Purpose of the study was to evaluate nine main meal foods over a 36-month period of storage. Three processing/packaging combinations of each food were included: (1) precooked frozen, packed in half-size steamtable aluminum foil trays; (2) heat-processed in cylindrical No. 10 cans; and (3) heat-processed in rectangular tray cans. Frozen products were stored at a constant -18C; heat-processed products at 21 and 38C. Products were evaluated initially and following 6, 12, 18, 24 and 36 months storage. Two sensory panels were used concurrently for product evaluations: (1) a panel of food technologists using a quality evaluation scale, and (2) a Natick RD&E Center employee panel using an hedonic scale. In addition to the sensory evaluations, interior surfaces of the containers were examined for corrosion after selected periods of storage. Prior to initial and six-month evaluations, all products were bacteriologically cleared for consumption. Sensory tests generally indicated that expected storage life of Tray Packs exceeded that of cylindrical cans at both storage temperatures. Precooked frozen products were generally highest rated, and No. 10 heat-processed products were lowest. Thus, of the heat-processed products, the Tray Pack foods were rated 'preferred'. The interior enamel food contact coating of the tin-free steel container was the most resistant to attack over the 36-month period of the study. Precooked frozen foods had aerobic plate counts that were well below Military standards and contained no fecal coliforms.