EVALUATION OF BEEF PATTIES CONTAINING soy PROTEIN, DURING 12‐MONTH FROZEN STORAGE

Abstract

ABSTRACT Patties containing 20 or 30% of soy protein (textured or concentrate) were stored at ‐17°C and evaluated tri‐monthly for 1 yr for effects of storage on organoleptic properties and chemical changes. Textured soy proteins from four manufacturers and concentrate from two manufacturers were tested. Fat content was about 20% for all patties. A 52‐member panel of adults, from 18‐60 yr of age, evaluated (without condiments) the 12 types of patties with soy and the all‐meat patties. A 13‐member panel evaluated the effects of condiments on acceptability. Chemical tests included proximate analysis (ash, fat, moisture and protein), pH, peroxide values and thiobarbituric acid (TBA) number. Mean scores for flavor, aroma and overall acceptability of the patties did not change significantly during the year of frozen storage. Some differences were significant in scores for tenderness, appearance and juiciness, but they were too small to be of practical importance. The addition of condiments to patties did not improve the scores for appearance and juiciness but did improve scores for flavor, aroma, tenderness and overall acceptability. Throughout the year, patties containing soy concentrate at either 20 or 30% rated significantly lower than most of the patties containing textured soy protein and the all‐beef patties when evaluated for flavor, appearance, aroma and overall acceptability. Although compositional changes in patties were evident during 12 months of storage, their magnitudes were inconsequential. Peroxide and TBA values increased during storage at a faster rate for all‐beef patties than for patties containing soy protein. Some panelists were able to detect old or rancid condition in some products during the 9‐ and 12 month storage but most palatability traits were not significantly different in patties that had been stored for up to 12 months. Soy protein additives fended to inhibit rancidity development.