Gelling characteristics of surimi from yellow stripe trevally (Selaroides leptolepis)

Thailand is one of the largest surimi producers in Southeast Asia. About 16 surimi factories are located in Thailand, with a total production of 96,500 to 113,500 metric tons of surimi per year of which 80% is exported to Japan and Korea and the remainder to Singapore and other countries (Hong & Eong [2005]). In general, lean fish have been used for surimi production. Due to the limited fish resources, especially lean fish, pelagic dark-fleshed fish have been paid more attention as a potential alternative raw material for surimi production (Chaijan et al. [2004]). Dark-fleshed fish make up 40% to 50% of the total fish catch in the world (Hultin & Kelleher [2000]), and the catch of those species in the Gulf of Thailand was approximately 844.2 metric tons in 2006 (Department of Fisheries [2006]). Due to the abundance and lower price, these pelagic fish can be used for surimi production. However, those pelagic fish have high content of dark flesh associated with the high lipid and myoglobin contents (Chaijan et al. [2004]). Those components contribute to the difficulties in making high-quality surimi (Chen [2002]; Ochiai et al. [2001]). The presence of sarcoplasmic proteins of dark muscle also contributes to the poorer gelation (Haard et al. [1994]). Sarcoplasmic proteins are able to bind with myofibrillar proteins, thus interfering the formation of strong gel network. In addition, lipid oxidation seems to be a distinct problem in surimi made from some dark-fleshed fish (Lanier [2000]; Wu et al. [2000]).Setting has been reported to play an essential role in the formation of protein cross-links mediated by endogenous transglutaminase (TGase) (Kumazawa et al. [1995]; Seki et al. [1990]). In general, setting has been applied to enhance gel strength of surimi. However, setting response can be varied, depending on fish species, and is related to habitat temperature of fish species (Shimizu et al. [1981]; Araki & Seki [1993]; Morales et al. [2001]). Benjakul and Visessanguan