| Grass carp (Ctenopharyn Odon Idellus) is one of the most popular freshwater species in China, due to its rapid growth, low price, and nutritional benefits. Fish surimi products, which are made from fresh muscle material, have been widely accepted by the public, due to their pleasant taste and high quality. The increase in consumer demand for high-quality food products has promoted the development of new technologies and ingredients.The effects of a specific rice starch (SRS), containing highly resistant starch (RSⅢ), on gel properties of grass carp(Ctenopharyngodon idella) and the influence of five levels of SRS (0%, 2%,4%,6%, and 8% w/w) on gel physicochemical properties at three different pre-incubation temperatures (4 ℃,25 ℃, and 40 ℃) were investigated. Gels with increasing amounts of SRS addition showed lower expressible water contents and cooking loss values than did control gels. SDS gel electrophoresis revealed no changes in protein patterns, regardless of different SRS-added levels at the same pre-incubation temperature, but an evident decrease in the MHC when the pre-incubation temperature increased. The texture properties, colour attributes, SEM were optimal in the treatments containing 4% w/w SRS at the pre-incubation temperature 25 ℃. Thus, the optimum SRS addition level and pre-incubation temperature are proposed to be 4% w/w and 25 ℃, respectively.Biochemical properties and gel-forming ability were investigated as a function of storage time to understand the effect of 10 MeV electron linear accelerator irradiation, combined with vacuum-packaging changes, on Atlantic salmon fillets during cold storage at 4 ℃. The results showed that compared with those of the control samples, pH, water soluble protein and extractable protein were not significantly altered by irradiation. However, pH, water soluble protein and extractable protein changed notably as storage time increased. While salt soluble protein (SSP), total volatile base nitrogen (TVB-N), a values,2-thiobarbituric acid (TBA) and total viable counts (TVC) were significantly (p< 0.05) affected by different irradiation doses, which inhibited the increase in TVB-N but promoted TBA values during the storage period. Moreover, irradiation up to 3 kGy did not significantly change the gel patterns, while the MHC patterns were slightly reduced with the increasing of the storage time.Overall, based on the research of the quality improvement of SRS on grass carp gels and the influence of irradiation on the shelf-life of salmon fish fillets, the main results are as follow: (1) Analysis of the grass carp surimi gels under different pre-incubation temperatures showed that SRS addition could positively improve the gel qualities and physicochemical properties. As a food additive, SRS could better improve the gel quality and meanwhile reduce the dosage of the traditional starch.(2) SRS has a positive and protective effect on the freeze-thaw stability of the grass carp gels, which presents a more stable quality through freeze-thaw process. The addition of 4% w/w SRS could significantly reduce the values of cooking loss and extractable water content.(3) Under the pre-incubation temperature 25℃ and 4% w/w SRS addition, gels achieved the optimized texture properties, color attributes and microstructure properties, In addition, different SRS addition levels could not significantly influence the gel protein profiles. With the increasing of the pre-incubation temperatures, MHC poses a decreasing trend.(4) E-beam irradiation could greatly prolong the shelf life of salmon fish fillets and have a good preserve effect. So it may play a practical value on the preserve of aquatic product. In addition, E-beam irradiation can also significantly influence the edible property of salman fish fillets, and the shelf life of which being vacuum package processed can up to 12 d. Furthermore, the dosage of 0.5 kGy irradiation can be viewed as the appropriate dosage. |
PDF Full Text Request