Development And Application Of Compound Preservative Based On Gracilaria Lemaneiformis Oligosaccharides On Tilapia Fillets

Tilapia is an important freshwater aquaculture economic fishes;its output occupies the second place of freshwater fish in the world.Tilapia fillets are finish machining products of tilapia,popular among consumers,how to extend the shelf life of tilapia fillets is a technical problem urgent to solve.Gracilaria lemaneiformis is the fourth largest cultivated algae of China,usually used to extract agar.Develop functional products of gracilaria lemaneiformis are helpful to enhance its additional value,promote alga industry’s reform and development.Therefore,this study was conduct an experiment that develop compound preservative based on gracilaria lemaneiformis oligosaccharides on tilapia fillets.First,we researched use biodegradable gracilaria lemaneiformis oligosaccharides carried out 30 days feeding experiment of SD rats.We finished rats blood indexes,blood biochemical indexes,pathology,and histopathological examination,Results display gracilaria lemaneiformis oligosaccharides no observed adverse effect level were greater than 5 g/kg,proved gracilaria lemaneiformis oligosaccharides were actually non-toxic,laid a solid foundation for gracilaria lemaneiformis oligosaccharides applied in food industry.Secondly,we conducted experiments that gracilaria lemaneiformis oligosaccharides treat tilapia fillets in 4 ℃.According to sensory analysis results,control group shelf life is 6 d,0.5%(W/V)gracilaria lemaneiformis oligosaccharides group shelf life is 9 d;According to texture analysis results,tilapia fillets hardness,chewiness,elasticity improve with the increase of concentration of gracilaria lemaneiformis oligosaccharides,proved gracilaria lemaneiformis oligosaccharides improve tilapia fillets hardness,chewiness,elasticity.According to total plate counts results,control group shelf life is 3 d,0.5% and 1.0% gracilaria lemaneiformis oligosaccharides group shelf life is 5 d;According to TVB-N results,control group shelf life is 6 d,0.5% gracilaria lemaneiformis oligosaccharides group shelf life is 8 d;According to K value results,control group shelf life is 2 d,1.0% gracilaria lemaneiformis oligosaccharides group shelf life is 4 d.In conclusion,gracilaria lemaneiformis oligosaccharides have the effects that extend the shelf life of tilapia fillets,0.5% gracilaria lemaneiformis oligosaccharides prolonging the shelf life of tilapia fillets to 5 d,prolonging shelf life 66.7%.Finally,we conducted experiments that gracilaria lemaneiformis oligosaccharides treat tilapia fillets in 4 ℃.According to Sensory analysis results,control group shelf life is 6 d,compounded agent B(0.5% gracilaria lemaneiformis oligosaccharides+0.2% tea polyphenols)group shelf life is 9 d;According to texture analysis results,compounded agent B group fillets hardness,chewiness,elasticity higher than other group fillets;According to total plate counts results,control group shelf life is 3 d,compounded agent C(0.5% gracilaria lemaneiformis oligosaccharides+0.5% citric acid+0.2% tea polyphenols)group shelf life is 6 d;According to TVB-N results,Control group shelf life is 6 d,compounded agent C group shelf life is 8 d;According to K value results,Control group shelf life is 2 d,compounded agent C group shelf life is 7 d.In conclusion,compounded agent C prolonging the shelf life of tilapia fillets to 6 d,prolonging shelf life 100.0%.In this paper,we developed compound preservative based on gracilaria lemaneiformis oligosaccharides on tilapia Fillets,solved the preservation processing problem in tilapia industry,implement purposes that prolong tilapia fillets shelf life;meanwhile,laid a solid foundation for gracilaria lemaneiformis oligosaccharides applied in food preservation,and promoting the high value utilization of gracilaria lemaneiformis.