Cai Li-yan

Abstract In this study, the method of maintaining the controlled freezing point and the effect of controlled freezing‐point vacuum drying ( CFVD ) on the quality of M uraenesox cinereus fillets were investigated. The quality assessment was based on color, 5‐inosine monophosphate ( IMP ), free amino acids ( FAAs ) and volatile compounds. Furthermore, comparisons were made among CFVD samples, those dried by hot air drying ( HAD ) and vacuum freeze drying ( VFD ). The results showed that the fillet temperature can be controlled within the scope of controlled freezing point by setting the vacuum pressure at 10–12 mbar, turning on the cold trap 40 min after CFVD (at −1 ± 1C) and regulating the heating plate temperature during the drying period. The highest increase in IMP (22.17%) and FAA content (34.54%) compared with the fresh fillets as well as the best color were observed in CFVD fillets. As to the carbonyl compounds, the major contributors to the odor and flavor of fresh fillets, the amount and types were the largest in HAD fillets, while the HAD fillets showed the significant browning. Therefore, CFVD is an effective method to control browning and increase the taste of fillets compared with HAD and VFD . Practical Applications Fish is a greatly perishable product because of its high protein content. Drying has been shown to be an efficient method of conservation. Controlled freezing‐point vacuum drying ( CFVD ) has been developed. In this study, the key technology challenge of CFVD and its effect on color and flavor of fillet, as well as the differences among the hot air drying and vacuum freeze drying, have been studied. The result shows that CFVD enables best quality in appearance and taste, which is quite helpful to establish an optimal drying condition for a more nutritious and high‐quality dried products.

By adding the time set to the evaluation object set and the evaluation index, we can get the evaluation index matrix with three dimensions.TOPSIS for multiple target decision is applied to space with matrix elements, and we can make comprehensive evaluation of enterprise economic benefit according to the relative distance between evaluation index matrix,best solution matrix and worst solution matrix. Based on introducing the principle of TOPSIS, an evaluation model for enterprise economic benefit is presented in this paper. Because of the great matrix process function of MATLAB, it is practical to use it to implement this evaluation model. The implementation techniques are discussed in detail. Lastly, an application example of this evaluation model is given.

The genetic relationship of M.ruthenica populations from seven provinces of China were analyzed by ISSR marker.16 primers with strong polymorphism and good repeatability were screened from 80 ISSR primers.133 bands were amplified from 44 populations M.ruthenica genomic DNA,with an average of 8.31 bands in each primer,of which(115 bands)87.08% were polymorphic.The genetic dissimilarity coefficients of M.ruthenica germplasm ranged from 0.436 to 0.908.44 populations M.ruthenica germplasm were divided into eight groups with the higher correlation of geography resource by UPGMA cluster analysis.