The Effect Of Hydrocolloid On The Quality And In Vitro Digestion Of High Ratio Potato Steamed Bread

Potatoes are widely cultivated due to their high nutritional value,cold resistance and drought resistance.As one of the world's four main staple foods identified by the FAO,they also have been playing an important role in ensuring global food safety and nutrition.China as the biggest potato cultivation and production country also implemented potato staple food strategy in 2015 which is respectively adding potato powder with high proportion into the traditional steamed breads,rice noodles and noodles.However,the lack of gluten and hard processing which obstructed the research and development of potato staple food.The previous study found that hydrocolloids had a good effect on the improvement of flour products.In this paper,the percentage of potato powder was increased to 40%by adding the hydrocolloids to the high proportion of PSB,and the effects of hydrocolloids on the processing quality,texture,water content,total phenol content and in vitro digestion of the high proportion of PSB were also investigated.The results are as follows:1.The optimum quality formula and processing of the high proportion PSB were determined by the combination of single factor and orthogonal test.The optimized results of the formula were as follows:the wheat flour was Zhong Yu,the amount of wheat gluten was 2.0%,the proportion of the potato powder was 40%,the dosage of ASK was 0.5%,the dosage of the yeast was 1.5%,the proportion of water was 75%,the fermentation time was 2.0h-2.5h and the proofing time was 20min-30min.The PSB is larger in the capacity and has strongly symmetrical apparent quality,and the surface was also milky white and flexible with delicate taste and sweet potato flavor.2.The effects of hydrocolloids on the structure and nutrient quality of the high proportion of PSB were also studied.The effects of the additive of hydrocolloids on the texture,water content and total phenol content of the high proportion of PSB were determined.In terms of texture,the three kinds of hydrocolloids all can significantly improve the texture index.And the best additive level of ASK and CMC were 0.5%and the TG was 1.0%.In terms of water content,water content contained in the high proportion of PSB was positively correlated with the additive of hydrocolloids and the strength of water retention from high to low order was ASK>CMC>TG.In terms of the content of total phenol,ASK and TG both had a certain protective effect in the total phenol of the high proportion of PSB,and the total phenol content was positively correlated with the amount of the dosage of ASK,but it was negatively correlated with the amount of TG.However,the change in total phenol content of the high proportion of PSB was not obvious with the additive of CMC and also did not vary with the increase amount.3.The effects of hydrocolloids on the digestibility of the high proportion of PSB were studied by in vitro digestion test.The effects of hydrocolloids on the starch content,hydrolysis and estimated glycemic index in the high proportion of PSB was also determined.The content of resistant starch was positively correlated with the dosage of ASK but negatively correlated with the dosage of TG and CMC.The results showed that the additive of hydrocolloids could reduce the estimated glycemic index of the high proportion of PSB by the analysis of the changes in hydrolysis and estimated glycemic index.The optimal dosage of ASK was 0.5%and the best additive of TG and CMC should not exceed 1.5%.