Study On Changes Of Food Quality Of Grass Carp Fishball During Processing

Grass carp provide people with the rich high quality protein and it is one of the main sources of protein. It can be used with the products of surimi such as fishball and fish cake in addition to eat directly, and fishball is people's main consumption style. Most of the study on fishball in the past years was its process improvement. In recent years, as the technique of HPME and GC-MS developed, there are more and more study on the volatile compound of grass carp, but there are rarely study on the changes of volatile components during fishball process. The object of study is to research the changes of quality of fishball during processing by texture analyser and GC-MS. In order to get the more detail described of the fishball quality. The results were as follows.(A) The changes of fishball quality in different supplement can be got by the spectrometer and texrure analyser. The formula were optimized through single-factor and orthogonal tests.1. Through single-factor tests, the results showed that the optimum content is:suit 3%; corn starch 8%; egg white 9%; water additive amount 15%.2. The orthogonal test result showed that there was no significant in the water holding capacity and whiteness of fishball; Finally the bast prescription of fishball was selected by sensory evaluation and priciple component analysis of texture index, namely, surimi 100g; salt 3g; suger 2g; gourmet powder 0.2g; ginger 7g; water 5g; egg white 9g; corn starch 6g.(B) We can get those results through the research of effect on the different common and modified starches and content.1. The results showed that the sample added corn starch has the best quality indxes value in the samples which were added water caltrop starch, potato starch, sweet potato starch, corn starch and cassava starch. The study on the effect of different mixed starch to the fishball quality index showed that the optimum ratio of corn starch to cassava starch is 1:1; the optimum ratio of potato starch to corn starch is 2:3.2. The results showed that the sample added crosslinked cassava starch has the best quality indxes value. The optimum percentage composition of crosslinked cassava starch is 7%. The optimum ratio of cassava starch to crosslinked cassava starch is 1:3.(C) In order to simplify the sample, in this study using the changes of grass carp surimi volatile compounds replaced the fishball volatile compounds. This chapter studied on the factors including the washing, heating-modes, adding salt and supplements affect the fishball quality indexes.The results showed that the factors such as heating, washing, adding salt and supplements could not change the characteristic material of surimi but could change the relative percentage content of the volatile components. The characteristic material of surimi is hexanal, octanal, nonanal, heptanal, 1-octene-3-ol,2-hendecanong, pentadecane, hexadecane and 6-methyl-5-heptylene-2-one, and so on. The ginger has special component which affect the surimi volatile component. By using principal compoment analysis of unpleasent odor, we know that the value of F is lower when the sample was washed and adding salt; The F value of sample which was heated is higher than the fresh surimi; When the heated temperture is 60℃, the F value of sample is the highest; the F value of sample is the lowest when the supplement was ginger. We can use the principal component analysis to evaluate the quality of fishball, because the result of sensory evaluation and principal component analysis coincided with each other.