Study On Gel Properties And Pudding Products Of Gelidium Amansii Agar

Agar has properties of good gel,thickening and suspension,widely used in bio-engineering,household chemicals,food and many other aspects.The gelidium amansii has high levels and quality gum and it is a good raw material for preparing agar.In the traditional agar extraction process,the long extraction time,the low yield of agar,coupled with the disadvantages of high brittleness,low transparency,poor viscoelasticity and prone to shrinkage,limit agar’s further development.In this paper,our lab provided the theoretical evidence for improving the extraction rate of agar and the quality of agar and using agar in the pudding products,we studied the agar gel agar extraction technology,explored the properties of agar gel and agar soy milk pudding product and shelf life.1.The high temperature and pressure method was used to extract the broccoli agar,the food grade citric acid was used as the acid extraction solvent,agar extraction rate and gel strength as an indicator.Through single factor and response surface experiments,the optimum extraction conditions were as follows:the concentration of citric acid was 0.03%,the extraction time was 33 min,the ratio of material to liquid was 1:36 and the extraction temperature was 110℃.The extraction rate of agar was 37.85%and the gel strength of agar was 873 g/cm2,the agar are high-strength products.2.The factors affecting the relaxation and texture characteristics of agarose agar were studied by means of low field NMR and texture analyzer.The results showed that the optimum conditions for the formation of agar gel were pH at 6.0～7.0.The addition of sodium chloride,calcium chloride or β-cyclodextrin blocked the formation of agar gel.The addition of appropriate potassium chloride,xylose or sucrose could promote the formation of agar gel,the best additions were 0.2%～0.3%,9.0%and 6.0%,respectively,and the effect of xylitol on agar gel formation was better than that of sucrose.The appropriate proportion of konjac gum,carrageenan or locust bean gum can be synergistic effect with agar,the optimum proportions were 15%,5%and 10%,respectively.With the increase of agar mass fraction,cohesiveness,hardness and gumminess of agar gel gradually increased,and the elasticity became larger and smaller.Agar gel relaxation time T23 was significantly correlated with gel hardness,cohesiveness,elasticity and gumminess,indicating that the physical state of water in gel was an important factor affecting gel texture.3.Using the method of single factor and orthogonal experiment,the agar soybean milk pudding formula was optimized by sensory evaluation and texture characteristics as the index.The optimum formula was as follows:soybean milk concentration 8%,xylitol 8%,potassium chloride 0.10%,total glue(agar + konjac gum)1.0%,konjac gum ratio of total gum 14%,milk powder 8%,lemon acid 0.14%,under this condition obtained agar soybean milk pudding color uniformity,milk flavor rich,uniform texture,taste smooth,delicate,moderate elasticity.4.With the sensory as the main index,the accelerated experiment was carried out,and the Weibull hazard analysis method was used to forecast the shelf life of agar soybean milk pudding.The results showed that the sensory shelf life of the products at 30℃,35℃ and 40℃ were 107,65 and 47 days,respectively.The Arrhenius equation was used to predict the shelf life of agar soy milk pudding at 25 ℃ for 207 days.