Restructuring steak from flakes of yellowfin tuna meat using low salt microbial transglutaminase (MTGase)

Abstract

Restructuring of fish meat can be done by using fragments of by-product processing such as fillet, loin, and steak of yellowfin tuna. The binder agent that may be the most efficiently used in restructuring the product is microbial transglutaminase (MTGase). Salt is needed to optimize the binding process of the restructuring product. The objective of the study was to determine the effect of low salt MTGase concentration as a binding agent on the quality of restructured yellowfin tuna steak compared to commercial yellowfin tuna steak. Research was designed with completely randomized design using 5 treatments in the 1.5% salt concentration, namely 0%, 0.3%, 0.5%, 0.7%, and 0.9%. The analyzed parameters were proximate (water content, protein, fat, carbohydrate, and ash), texture, colour and water holding capacity. The sensory test was conducted to compare restructured products with commercial tuna steak. The results indicated that the best treatment to the addition of MTGase was 0.5% based on the physical properties of the product, the nutritional content and sensory test. In sensory, MTGase was able to maintain the colour (brightness) of the products as they were darker than the commercial tuna steak and improve the product's texture (hardness) in the addition of 0.9% MTGase.