Studies on The Optimization of Mince Operation in Tilapia Surimi Preparation and Fish-Gel Qualities Effected by Additives

• Main Authors: Chang-Yu Lin, 林昶宇
• Other Authors: Ming-Sheng Kong
• Format: Others
• Language: zh-TW
• Published: 2001
• Online Access: http://ndltd.ncl.edu.tw/handle/62950516501564870570

碩士 === 國立海洋大學 === 食品科學系 === 89 === This research was a follow-up study on the optimization of tilapia surimi and fish-gel processing in this laboratory. The work remaining to be studied was the optimization of mincing operation, including: 1. Choosing the prepared mincing machine between silent cutter and grinder based on their mincing efficiency, and establishing optimized operation condition. 2. Investigating the role of NaCl addition in mincing operation and its optimized adding quantity. The optimized surimi preparation conditions thus established was adopted prepare tilapia fish-gel with various additives. Their texture profiles were constructed and used to compare with those of commercial products. Two popular type of mincing machines, silent cutter and grinder were used for comparison. Their maximum conversions of actomyosin from muscle form to solublized form based on the extractability of salt-soluble protein in surimi were 90% and 80%, respectively. Similar results were found by DSC study. In addition, the lower surimi protein mechanical damage in terms of TCA soluble peptide content, was found for silent cutter. These two factors evidenced that silent cutter had higher mincing efficiency. Fish-gel qualities, including breaking force, deformation at break and gel strength also evidenced that the products of silent cutter were superior than those from triple-beam grinder. The higher hardness and TSRM G’ value were higher for fish-gel prepared by grinder. No significant difference in mincing efficiency was effected by the amount of NaCl (0~3.5%) added during mincing. However, significant differences were found in gel strength of their cooked products. These results revealed that NaCl addition did not offer any contribution to the mincing efficiency, however did offer great deal of influence on the gel-formation during cooking. The optimized amount of NaCl addition was found to be 2.5~2.7%. Upon using this newly established mincing condition, in combination with previous optimized conditions of holding treatment (Ho, 2000; Chen, 1998), tilapia fish-gel with various amount of additives were prepared. Their qualities were compared with commercial fish-gel products. Among them, fish-gel prepared from tilapia surimi without holding treatment (free-AM form surimi) could be modified with addition of sufficiency amount of starch and water to be fallen into the domain of commercial products. Whereas, those prepared with the optimized holding condition (3.5 mM Ca2+ added, 25℃/8 hr) to contain the TGase crosslinked AM type surimi, possessed superior qualities. All, particularly deformation at break of fish-gel had much higher than commercial products.