Study On Selection Of Apricot Varieties For Drying And Drying Technology

These indexes including total sugar, total acid, Vc, water soluble solides, moisture and carotenoid of 76 varieties apricot were determined.76 varieties such as Dahuanna, Jianali, Kumaiti and Saimaiti were dried naturally, the varieties of apricot for drying was selected by sensory evaluation and determination of the total sugar, total acid, moisture, carotenoid and drying apricot yield. The different treatments by sulfur and no sulfur, the conditions of drying, the sterilization and the second drying ways of dried apricot were studied. The physical and chemical indexes, sensory evaluation were tested. The flavor material of dried apricot was tested by GC-MS. The results showed that these varieties including was selected by sensory evaluation, they are"Dahuanna","Heiyexing","Saimaiti","Kumaiti","Xiaobaixing","Qiaoerpang","Xiheiyexing","Kabakeximixi","Mantouyulvke","Kuchetuoyong".When ratio of sugar to acid of the fruit 4～11, the results of quality evaluation of dried apricot and ratio of sugar to acid of apricot assumes the tendency which the linearity increases progressively.The optimal drying technology was as follows: the Kumaiti apricot was scalded for 3 minutes in 90℃hot water, then treated by NaHSO₃ solution 3.75g/L for 1 hour, ratio of sugar to acid 12.04, the drying ratio 26.46%, the sulfur 89mg/kg, L*31.20, b* 23.07.On this condition, the products have good quality while the drying time is short.Using sulfur soak NaHSO₃ 2.5g/L,the weight of fresh apricot 4kg, soaking times 30 minutes; Using sulfur fumigation the 4g/kg sulfur at the 1m³ plastic to processing 4h, the residual sulfur is 336.7 mg/kg.The optimum conditions of no sulfur drying technology were as follows: the apricot was scalded for 3 minutes in 90℃hot water, then treated by mixture of Vc 0.4%, NaCl 0.6% and Citric acid 0.3% for 20 minutes.The optimal sterilization condition for dried apricot was 95℃for 5 min.The optimal second drying condition was 60℃for 3.25h.The aroma compoenents of dried apricot were extracted and determined and 84 aroma components were identified."Dahuanna","Heiyexing","Saimaiti","Kumaiti","Xiaobaixing","Qiaoerpang"were analyzed.The results showed that there were 46,53,29,52,50 and 51 aroma components respectively in six cultivars. There are 16 common aroma components. In dried apricots detected many aldehydes, ketones, alcohols and single terpenols substances, monoterpene substances are in the specific components of apricot.