Effect of different washing conditions on the gel forming ability of tilapia (Oreochromis niloticus) mince

Abstract

This study was carried out to observe the effect of washing on tilapia mince. To evaluate the
effects of washing, salt-ground (3% NaCl) paste in tubes was incubated in water baths at temperatures of 20,
30, 40, 50, 60, 70and 80ºC for 2 hours (one-step heating) followed by 30 min heating at 90ºC (two-step
heating) to make gel. The resulting suwari gels were subjected to instrumental puncture test. The optimum
setting temperature to obtain high quality finished products from surimi was found to be 40ºC for one-step
heating and 50ºC for two-step heating. A two-step heating schedule of incubation at 50ºC/2 h and cooking at
90ºC/30 min gave high textured good quality suwari gel for both unwashed and washed mince. Washed
mince surimi is always superior to unwashed mince surimiin gel quality. In order to find out an efficient
washing technique of tilapia mince, a series of experiments on washing solution (0%, 0.05%, 0.1%, 0.15%
and 0.2% NaCl), washing period (5, 10 and 15 min.) and washing frequency (1 wash, 2 wash , 3 wash and 4
wash) were conducted. A significantly good textural and sensory quality (p<0.05) of gel and a fine grade
surimi was obtained from tilapia mince washed with 0.1% NaCl solution. Two times washing gave the best
result. Washing time limited within 10 min (6 min agitation, 4 min settling) was found to give good quality
surimi.