Research on Technology for Primary Processing of Triploid Rainbow Trout(Oncorhynchus Mykiss)
Using triploid rainbow trout from Qinghai Province as the research object,the meat colour,meat quality and nutrient composition of the fish were determined by studying the key point technologies in the primary processing process of triploid rainbow trout:fasting time,pre-cooling temperature,lethality and bloodletting de-gree.The results indicated that different fasting durations had no significant impact on the yellowness,sensory flesh color,chewiness,adhesiveness,cohesiveness and pH of the fish flesh(P>0.05).Fasting for 3 days increased the lightness and redness values of the flesh(P<0.05),with no significant changes in nutritional composition(P>0.05).However,fasting for 15 days resulted in the highest hardness and chewiness of the flesh but significantly re-duced its nutritional content(P<0.05).Different pre-chilling temperatures did not significantly affect the flesh color,elasticity and nutritional composition(P>0.05).At 0℃pre-chilling,the hardness,adhesiveness,and pH value of the flesh were significantly higher(P<0.05),while at 15℃,chewiness and cohesiveness were sig-nificantly higher(P<0.05).The method of slaughter had no significant effect on the redness,yellowness,sensory flesh color,elasticity,cohesiveness,adhesiveness,pH and protein content of the flesh(P>0.05).However,the hardness,chewiness,and fat content were significantly higher in the group where the fish were stunned and bled compared to the groups subjected to air asphyxiation or head percussion(P<0.05).The degree of bleeding had no significant impact on the lightness,hardness,pH,fat and moisture content of the flesh(P>0.05).The flesh from fish bled to 50%showed the lowest redness value but the highest elasticity(P<0.05);70%bleeding resul-ted in the highest chewiness(P<0.05),while unbled fish had the highest protein content(P<0.05).The opti-mal primary processing scheme for triploid rainbow trout was a fasting duration of at least 3 days,pre-chilling at approximately 0℃,slaughter by stunning and gill cutting,and 70%bleeding.
万方数据
维普
