Investigation of fat replacement systems for low-fat, precooked, coarse-ground beef products

Abstract

The effects of various particle size reduction methods and incorporation of selected hydrocolloids on the sensory, textural and physical characteristics of precooked, low-fat beef patties were investigated. Sensory evaluation showed that coarse-ground patties were harder, denser, more easily fractured and less juicy than flaked or flaked/ground treatments. All treatments were similar in flavor attributes. Patties of coarse-ground treatment had higher cooking and reheating losses and higher shear after reheating than flaked or flaked/ground treatments. Flaked patties had higher yields and improved textural properties; however, they also showed surface "puffing" and an internal air pocket after microwave reheating. The flaking-grinding combination appeared to produce more desirable, low-fat, precooked beef patties with optimum yield and textural properties. Patties containing an alginate/carrageenan combination had higher yield and moisture and lower shear than those containing alginate or carrageenan alone within the same fat levels. Alginate/carrageenan patties containing 5 or 10% fat were comparable in yield, shrinkage, fat retention, shear and water-holding capacity. Alginate appeared to improve texture slightly more than carrageenan, but carrageenan tended to release more free water after cooking and reheating. Patties with 10% fat were generally lower in shear, yield and percentage released free water as compared to their 5% fat counterparts. Low-fat, precooked, ground beef parties containing alginate/carrageenan combination were superior to regular beef patties (20% fat control) regarding yields and textural properties, and should be considered when low-fat beef patties are destined for microwave reheating. The protein-hydrocolloid interactions were characterized in an emulsion containing selected hydrocolloids. Following heating, actin in the carrageenan treatment appeared to increase in molecular size or change in shape but the result was reversed in alginate/carrageenan treatment. Protein net charge did not change in the control or alginate treatment when the temperature increased from 65.6 to 71.1°C. The results suggested that alginate could provide more protective effects to myofibrillar proteins regarding unchanged protein concentrations and stable configuration during heat denaturation.