REPPOND ET AL.: WALLEYE POLLOCK: CHANGES WHEN HELD IN SEAWATER 



presented here on the accumulation of DMA and 

 FA in the flesh of walleye pollock stored as fillets 

 at l"-3° C. Kramer et al. (1977) reported much 

 lower values of DMA but this was probably due to 

 differences in sampling and analytical technique. 



Effects of Washing Ground Flesh 



Washing improved the appearance of minced 

 pollock (Miyauchi et al. 1977) and is a common 

 procedure in the utilization of pollock in tradi- 

 tional Japanese products lOkada and Noguchi 

 1974). The water to flesh ratio of 2:1 used in this 

 experiment was much smaller than the 5;1 or 

 larger values used by other investigators. Wash- 

 ing the ground flesh of ice-held pollock increased 

 the apparent yield but no change in yield occurred 

 for samples held in MRSW. If yield data are con- 

 verted to a salt-free, constant 187? solids basis 

 however, the washing procedure actually de- 

 creased the yield to 3(>7f for samples from either 

 system. Yamamoto et al. ( 1975) reported that 209'( 

 of the protein content of ground pollock can be lost 

 under certain washing conditions. Consequently, 

 for commercial pui-poses, any beneficial results 

 from washing would have to be balanced against a 

 sizable decrease in yield. The advantages of wash- 

 ing are that the product is lighter in color, has less 

 odor, and, in the case of fish held over 4 days in 

 MRSW, has an acceptable salt content (Table 1). 

 TMA, TVA, and NPN content are also reduced by 

 about half on washing. 



CONCLUSIONS 



Walleye pollock can be held to 6 days if iced 

 thoroughly and still be acceptable for human con- 

 sumption. Palatable fillets can be obtained from 

 ice-held fish whose physical appearance in the 

 round would probably cause them to be rejected for 

 human consumption. In MRSW, the rapid ac- 

 cumulation of salt in the flesh would prohibit hold- 

 ing pollock more than 4 or 5 days at the 1.5:1 brine 

 to fish ratio utilized in this experiment. The de- 

 velopment of a disagreeable taste other than sal- 

 tiness may be responsible for some of the decrease 

 in flavor scores. The beneficial results of washing 

 the ground or minced flesh of pollock will probably 

 be negated by the decrease in yield and the prob- 

 lems associated with disposing of the wash water. 

 Analysis for TMA or TVA may provide a chemical 

 index of spoilage for pollock held in ice; for pollock 

 held in MRSW, analysis for TM AO or EPN may be 



useful. Further work is needed before limiting 

 values for TVA, TMA, TMAO, or EPN can be pro- 

 posed as objective indicators of the acceptability of 

 fresh pollock. 



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