Preparation And Storage Stability Of Asparagus Nutritious Instant Meal Replacement Porridge

With the development of society,meal replacement food gradually occupies an important position in people’s lives.However,most meal replacement products are mainly semi-finished products,and most of them need to be brewed or processed again.Instant meal replacement products are favored.Porridge is one of the indispensable varieties in China’s diet.At present,there are two kinds of porridge on the market:dehydrated porridge and ready-to-eat porridge,but the existing meal replacement porridge is mainly dehydrated porridge,and there are few ready-to-eat meal replacement porridge.Asparagus contains a variety of nutritional elements and bioactive components,which is a kind of nutritious vegetable with high value.In China,the tender stems of the upper part of asparagus are directly sold or processed into canned asparagus and other products,while the rest are usually discarded,which not only occupies a large volume but also has high nutritional value.Deep processing can improve the utilization rate of asparagus and increase its economic benefits.In this paper,asparagus was used as raw material,and the effects of different drying methods on the quality of asparagus powder were studied,and the most suitable drying method was selected to prepare asparagus powder.On the basis of traditional porridge,the formula and technological parameters were optimized by single factor test and response surface analysis,and a kind of asparagus nutritious instant meal replacement porridge was produced.Its storage stability was studied and its shelf life was predicted by accelerated destruction test.The main contents and results are as follows:(1)Study on preparation technology of asparagus powder.By exploring the influence of different steam blanching time on the peroxidase activity of asparagus,the best steam blanching time of asparagus was 200 s;Hot air drying,vacuum drying and vacuum freeze-drying were carried out on blanched asparagus respectively.It was found that vacuum freeze-drying was superior to hot air drying and vacuum drying in preserving the contents of protein,total sugar,total flavonoids,saponins and Vc in asparagus powder.At the same time,the asparagus powder after vacuum freeze-drying has the best water absorption and oil absorption.low bulk density and uniform particle dispersion.Sensory scores of color and fragrance were significantly higher than those of hot air drying and vacuum drying.Therefore,although the energy consumption of vacuum freeze-drying is slightly higher than that of hot air drying,vacuum freeze-drying is still used to prepare asparagus powder.(2)Development of asparagus nutritious instant meal replacement porridge.The optimum soaking parameters of soybean,red kidney bean and coix seed were determined to be soaked at 50℃ for 3 h by studying the change of water absorption rate of raw materials.The addition of asparagus powder,sucrose fatty acid ester,mogroside,stabilizer,material-liquid ratio and high-pressure cooking time were used for single factor and response surface optimization.Based on sensory evaluation,water content and viscosity,the final formula and technology are as follows:rice 25%,soybean 35%,red kidney bean 30%,coix seed 5%,asparagus powder 5%,sucrose fatty acid ester 0.12%,mogroside 0.016%,xanthan gum and guar gum 0.19%in a ratio of 1:4.At the same time,it can control energy well and solve the problems caused by low protein diet in meal replacement diet.(3)Study on storage stability of meal replacement porridge.The changes of texture characteristics,color,pH value,soluble solid content and total number of colonies of asparagus nutritious instant meal replacement porridge at different temperatures(4℃,25℃,37℃)were studied.It was found that the hardness of asparagus nutritious instant meal replacement porridge stored at 4℃ 25℃and 37℃for 48 d increased,the adhesiveness decreased,and the elasticity did not change significantly.The L*value of meal replacement porridge increased first and then decreased slowly with the increase of storage time,while the a*value increased gradually with the increase of storage time,and the b*value did not change obviously.The pH value basically decreased first,then increased and then decreased.The content of soluble solids remained basically unchanged,and no colonies were detected.The sensory score of meal replacement porridge decreased with the storage time,and the higher the temperature,the faster the sensory score decreased.To sum up,the asparagus nutritious instant meal replacement porridge stored at 4℃ for 48 d has fine and silky taste,uniform texture,no obvious moisture layer and coagulation and precipitation,and retains a strong asparagus fragrance,which has good storage stability.At the same time,through accelerated destructive test,the total number of colonies,pH value and sensory score of asparagus nutritious instant meal replacement porridge were determined regularly at 47℃ and 57℃,and the shelf life of meal replacement porridge at 47℃ and 57℃ was determined to be 88 d and 48 d respectively.According to the formula,the shelf life of asparagus nutritious instant meal replacement porridge is predicted to be 332 d at 25℃.