Study On Physicochemical Properties Of Ginger Powder Extracted By Enzymatic Hydrolysis And Establishment Of Prediction Model Of Thermal Degradation Of Gingerol

In this paper,ginger is the main research obj ect.The effect on physicochemical properties and biological activity of ginger powder in all the process were studied.By comparing the changes of juice yield,soluble solids,DE value,the content of gingerol and flavonoid before and after pretreatment and enzymatic hydrolysis,the pretreatment method was determined to be 1:5 beating.The enzymatic hydrolysis conditions were as follow:time 60 min,temperature 53 ℃,the amount of a-amylase 7.0 U/g,the amount of cellulase 23.0 U/g,pH 5.7,and without vibrating.On this basis,the ginger extract was dried.The effects of vacuum freezing drying and hot air drying on the physicochemical properties,functional factors and storage stability of ginger powder were compared.The results showed that compared with hot air drying(HD),vacuum freeze-drying(FD)had a stronger dehydration ability.The obtained ginger powder particles were larger,looser,with a better fluidity and a shorter dissolution time.The color,flavor and the active ingredients of ginger were maintained better as well.But with a higher hygroscopicity,it tended to agglomerate,and must be stored under 25 ℃ and RH=22%.Gingerol,the main active substance of ginger,tended to degrade during heat treatment,which affected the biological activity of ginger powder.In this paper,the thermal degradation of gingerol under different acid-heat conditions were studied.The BP-neural network(BP-ANN)prediction model of thermal degradation of gingerol was established under different treatment conditions(temperature,treatment time and pH)with the R2 above 0.99.The genetic algorithm(GA)was used to optimize the BP-neural network,and a more relevant and accurate prediction model with the R2 above 0.995 was established.