Effect of tempe protein isolates addition on beef meatballs characteristics

Meatball is a processed meat emulsion product made from starches, meat, water and seasonings. Problems that often occurred in meatball production are the lack of compactness of the product texture, as well as low water holding capacity due to poor emulsification process during the forming of the meatball dough. Soy protein isolate (SPI) is usually used to improve the texture quality and act as a binder on meat emulsion products. Tempe protein isolates (TPI) can be used as an alternative for SPI because of their higher protein quality compared to commercial SPI due to the fermentation process. TPI used in this study was made from germinated soybean tempe (GTI) and nongerminated soybean tempe (NGTI). The purpose of this study was to examine the effect of SPI, GTI and NGTI application and concentration on the quality of the meatballs produced. The protein isolate concentration used were 1, 2 and 3% based on the weight of the meat. Results showed that the WHC value of meatballs increased with the increasing concentration of protein isolates used. The highest WHC value (91.60%) was obtained in GTI treatment with 3% concentration, not significantly different from 3% NGTI (91.06%) and significantly higher than 3% SPI (90.93%). In the overall texture parameters, GTI produces meatballs with higher scores than SPI, but it was not significantly different from NGTI. The highest protein content (13.39%), was achieved by GTI (3%), not significantly different from GTI (1%) (12.69%) but significantly higher than SPI (3%) (10.70%). GTI (1%) meatballs had the highest sensory acceptance scores on the attributes of colour, taste, hardness, juiciness, chewiness and overall preferences. It showed that GTI was useful to reduce the concentration of protein isolate used.