EFFECT OF LEACHING PROCESS WITH DIFFERENT SALT CONCENTRATIONS ON THE QUALITY OF CARP (Cyprinus carpio) NUGGETS STORED UNDER FROZEN CONDITION

Surimi is a Japanese term for mechanically deboned fish flesh which has been washed in water with salt and mixed with cryoprotectants to extend frozen shelf life. Salt addition assists in protein solubilising by extracting the salt-soluble myofibrillar proteins in raw meat which helps to open up the fish tissues so that surimi can incorporate other ingredients in order to form the surimi paste. This study was conducted to evaluate the effect of leaching process with different salt concentrations on the gel strength, proximate composition, microbial load, whiteness, and sensory evaluation of the Carp (Cyprinus carpio) Nuggets. Four different salt concentrations on the leaching process were achieved as experimental treatments: 0.2% NaCl at 1st, 0.2 % NaCl 2nd and 0.3% NaCl at 3rd Cycle (Treatment 1), 0.3% NaCl at 1st, 0.3% NaCl 2nd and 0.4% NaCl at 3rd Cycle (Treatment 2), 0.4% NaCl at 1st, 0.4% NaCl 2nd and 0.5% NaCl at 3rd Cycle (Treatment 3), and 0.5% NaCl at 1st, 0.5% NaCl 2nd and 0.6% NaCl at 3rd Cycle (Treatment 4). Based on the results during the 27 days of frozen storage, it was found out that the increase of salt concentration in leaching process will result in an increase of gel strength ability of the surimi which the statistical result indicated a high significant (p<0.01) and significant differences (p<0.05) in Folding test and Teeth Cutting test of the Carp surimi thus, an increase of salt concentration will decrease of whiteness meanwhile, all Treatments had passed the standard limit of Total Plate Count (TPC) which is 500,000 cfu/g (FAO, 2001). Proximate Composition shows varying result because the Carp (Cyprinus carpiio) was used were taken from different sources. The composition of Carp nuggets resulted to Treatment 2 getting the least percentage of ash and fats while Treatment 3 got the least percentage in protein and a gradually increase in moisture in Treatment 1 to 3 but slightly decrease in Treatment 4. Overall, Treatments resulted no significant difference (p>0.05) with regard to sensory attributes and all Treatments were Judged as acceptable by the panelists.