The Effect Of Processing Technologies On The Quality Of Melon Juice

Using Xinjiang Melon as test materials, at the same time, total phenolic, flavonoids, total sugars, totalacid, vitamin c, volatile components, browning index, as test targets, we aim to find the infLuences of keyprocesses such as clarification, microwave sterilization, and freeze concentration on the quality of Melonjuice, so as to provide researching foundation manufacturing technology and technical parameters ofono-thermal processed Melon juice. The results of the study are as follows:(1)Compared the influences of freeze concentration and vacuum thermal concentration on quality ofMelon juice, the results indicated that the browning degree of58.6°Brix Melon juice increased by1.8%and6.7%separately, the loss of total phenols were0.147%and0.182%separately, flavonoids Loss rate were7.15%and16.17%separately, VC loss rates were43.3%and93.9%separately, total colonies were1/5and1/4of blank, Compared to vacuum thermal concentration, loss of total phenols and flavonoids of freezeconcentrated Melon juice were at a less extent, and the color and browning index changed a littLe, andtotaL sugar, total acid, and VC lost a littLe, the total clonies wasless.（2）Compared the effect of thermal sterilization and microwave sterilization on quality of melon juice,the result showed that after treated by the two sterilization methods above at65℃,the total number ofcolonies were1/4and1/3of CK, the loss rate of VC were40.98%and28.36%, total phenols were56.58%and35.95%separately, polyphenol oxidase (PPO) inactivation were76.2%and98.9%separately,peroxidase (POD) inactivation were75.4%and92.9%separately, loss of total phenols and flavonoids ofmicrowave sterilizated melon juice were at a less extent, and the color and browning index changed a little,and VC lost a LittLe, the enzymes was effectively passivated.（3）The fresh Melon were used as the raw material to make fresh dates pulp. Extracting the aromacomponents of the dates which was heated by different tempretura, and analyzed the changes of aromacomponents bu GC-MS. The results showed that with extension of treatment tempera in a certain period oftime,, the type of the aroma components and the content of the total material were still increasing,and the majority aroma components were ethyl acetate, amyl acetate, propyl acetate,1,1-cyclopropanedicarboxylic methanoL,2-amino-2-methyL propane,2trans,4trans-Aoi diene aLdehyde,carvacrol and so on. The content of aeaters recduced and the content of acids and alcohols increasedsignifacantly with the eatension of Melon juice paste teat treatment tempura.(4)Storage temperature made significant influences on the quality of concentrated MeLon juicecoLor, browning index, total phenols, flavonoids, total number of colonies of melon juice stored at4℃and25℃after84days changed less, stored at4℃was better, while targets all above of the melon juice storedat37℃for14days changed greatly, and total phenols such antioxidants seriously lost.