Effects Of Rice Culture And Pond Culture On The Quality Of Chinese Mitten Crab

Chinese Mitten Crab(Eriocheir sinensis)is a kind of important freshwater cultured crustacean in China.It is very popular with consumers because of its high nutritional value,pleasant smell and taste.With the continuous development of science and technology,as well as the increasing demand of the Chinese market,freshwater crabs have been widely cultivated in ponds,lakes and reservoirs since 1990.As of 2015,China's freshwater cultured Chinese mitten crab production has reached 823 thousand and 200 tons.In recent years,with the enhancement of people's living standards and health consciousness,people on the freshwater crabs are increasingly high,not only requires large crab fatness,rich nutrition,but also pay more attention to the quality and safety.Rice farming has become an advocate in recent years farming model,but because of the rice farming Eriocheir sinensis mainly focus on the yield,environmental and economic benefits,the lack of evaluation for paddy farming Eriocheir sinensis quality.Rice farming as a kind of new farming methods,according to the specification of the rice fish,not only solve the problem of the crab growth stage illumination is insufficient,but also expanded the activity space of crab,paddy field water level is appropriate,better light conditions,dissolved oxygen is sufficient,abundant natural food,less disease,paddy field has a good ecological environment.The characteristics of low cost and high efficiency gradually increase the proportion of breeding in recent years.In this study,the Chinese Mitten Crab(Eriocheir sinensis)cultivated in paddy field and pond culture was used to explain the effect of rice culture on the quality of Eriocheir sinensis.The Chinese mitten crab main edible part(muscle,hepatopancreas,gonad)basic nutrition,biochemical index,fatty acid composition,amino acid analysis,a flavor nucleotide,and through artificial sensory evaluation,electronic nose and tongue analysis by headspace solid phase microextraction gas chromatography mass spectrometry for detailed analysis the odor substances in edible part.Based on the analysis and discussion of the experimental results,the quality of Chinese Mitten Crab(Eriocheir sinensis)in rice field was determined.The results are as follows:1(1)The Chinese Mitten Crab Eriocheir sinensis in rice field can reach the weight of Yangcheng Lake crab two in weight.(2)The different breeding methods had the least impact on the body and the hepatopancreas and gonad of Chinese Mitten Crab(Eriocheir sinensis),but not the same as that of female crab and male crab.(3)There was no significant difference between the gonad and hepatopancreas fat of female crab in the two culture methods,and there was no significant difference in the rest.(4)Unsaturated fatty acids were the main components of all edible parts.(1)Free amino acid contentin liver,muscle,gonad were rice crab<pond crab,rice crab >pond crab,and rice malecrab>pond malecrab,pond female crab<pond female crab,respectively.Among them,the bitter free amino acid of rice crab was much less than that of pond crab.(2)In the aspect of flavor nucleotides,the EUC value of muscle and female gonad of rice crab was higher than that of pond crab,while the EUC value of hepatopancreas of crab in rice field was lower than that in pond crab,TAV value of EUC were all higher than 1,and TAV of the body muscle of rice crab was higher than that of crab.(3)According to the results of the principal component analysis by the electronic tongue,it indicated that there was an obvious setaration between the two kinds of crabs.The discrimination of female crab was higher than that of male crab and the significant difference was shown in female crabs between the two farming methods.(4)Combined with the artificial sensory analysis,in the sensory evaluation,The bitter intensity of hepatopancreas of was significantly lower than that of pond crab.The overall preference of hepatopancreas of was higher than that of pond crab.3(1)Artificial sensory evaluation showed that the effects of the two culture methods on the muscle odor of Chinese mitten crab were the smallest,and the effect on hepatopancreas was the most significant;(2)The PCA analysis of the edible parts of the electronic nose showed that the effects of the two methods on the overall odor profile of Chinese Mitten Crab(Eriocheir sinensis)were the smallest,and the influence on the hepatopancreas was the largest.(3)The effect of two kinds of culture conditions of Chinese mitten crab meat and gonadal odor is not obvious,has a significant impact on the liver pancreas;electronic nose to the edible part of PCA analysis shows that the influence of two kinds of culture of Chinese mitten crab can smell the edible part of the overall outline,with minimal impact on body meat,hepatopancreas maximum.(4)Benzaldehyde,(E)-2-and aldehydes were the key odor compounds in hepatopancreas and gonads of female and male crab.The quality of Chinese mitten crab in paddy field is better than that in pond culture.The quality of Eriocheir sinensis in paddy field can basically meet the needs of consumers.