Effect Of Drying Methods On The Qualities Changes Of Dried Thick Skin Apricot During Drying

Hot air drying technology in the dried fruit industry in Xinjiang.Compared with the traditional sun drying apricot slices,hot air drying has made the dried apricot slices have great improvement in color,safety and hygiene,but the flavor quality of dried apricot slices is different from that of traditional sun drying apricot slices.So in this experiment,Apricot is used as raw material,we use sun drying,hot air drying at 40? and hot air drying at 60? to dry apricot,to study the effects of different drying methods on the quality and flavor of apricot.The experimental results are as follows:1.Comparing the three drying methods,the higher the temperature,the shorter the drying time of apricot.The efficiency of hot air drying is higher than that of sun drying,exterior color is also one of the important indexes to evaluate the quality of dried apricot slices.The best color and brightness of dried apricot slices is the hot air drying method at 40?,followed by sun drying method,and the worst color of dried apricot slices is hot air drying method at 60?,browning degree affects the color of dried apricot slices,with the increase of drying time,browning degree increases,and the higher drying temperature,the longer drying time,the greater browning degree.The contents of total acid and organic acid in dried apricot slices after three treatments decrease,and the total sugar content increases.The dried apricot slices by hot air drying method at 40?accumulate most the total sugar content.2.Drying method has effect on aroma components and content of dried apricot slices,25 aroma components are detected in dried apricot slices by hot air drying method at 60? and 29 aroma components are detected in dried apricot slices by hot air drying method at 40? and sun drying methods.The main aroma components affecting the aroma quality of dried apricot slices are esters,aldehydes,alcohols and ketones.Comprehensively comparing the three drying methods,the relative content of aromatic compounds by hot air drying method at 40? is higher than that by the other two methods.Compared with sun drying method,the aroma components by hot air drying method at 40? are close to it.In the drying process,the main aroma substances of dried apricot slices are carotenoids degraded products,beta-ionone,beta-cyclocitral,dihydroactinolide,tea-spirane,etc.The content of them after drying is higher than that before drying.The total content of carotenoids degraded products in apricot slices dried by hot air drying method at 40?is higher than that in apricot slices dried by hot air drying method at 60? and sun drying method.According to the comprehensive analysis,hot air drying mehtod at 40? is the best condition for drying the fresh apricot.3.The content of carotenoids decreases with the extension of the drying time,which is contrary to the change of content of carotenoids degraded products.The enzymatic activity of POD is the lowest at 60?,and the content of carotenoids degraded products is also the lowest at 60?.The change trend of enzymatic activity of POD is the same as that of carotenoids degraded products.The enzymatic activity of LOX decreases with the increase of drying time,at 60?,the enzymatic activity of LOX decreases sharply,after 30 hours,the enzymatic activity of LOX decreases to a minimum close to inactivation,combined with the analysis of the change of carotenoids degraded products in dried apricot slices dried by hot air drying method at 60?,the relative content of aroma compounds is the highest when their drying time is 30 hours,and then gradually decreases.But the content of carotenoids degraded products increases at 40? and sun drying.Because LOX enzyme maintains certain activity at this temperature,it can take part in carotenoid degradation.This shows that the temperature of hot air drying has a great influence on the carotenoid degradation and enzyme activity,high temperature inhibits the enzyme activity,which is not conducive to the carotenoids degradation.