摘要:本研究采用冷冻干燥-真空微波组合干燥技术制备小番茄脱水制品,以期缩短干燥时间、改善小番茄脱水制品的营养和外观品质。以干燥过程中水分、维生素C、色泽、体积密度、复水比以及综合感官评分等为试验测定指标,通过单因素试验和正交设计试验,研究确定冷冻干燥预干燥与微波真空脱水后续干燥的水分转换点和工艺技术参数。结果表明,小番茄组合干燥的最佳技术参数为:在70℃下热烫预处理60s,然后于-53℃下真空冷冻干燥12h,最后于微波功率6 kW、温度为55℃条件下干燥200 s。在此条件下所得制品的维生素C损失率为33%,复水比为4.79,收缩率为0.63,其感官品质和营养成分接近真空冷冻干燥的效果,同时联合干燥方式也能大大节省干燥时间和降低能耗。
关键词 小番茄;真空微波干燥;真空冷冻干燥;组合干燥
Abstract:In this study, the combined freeze and microwave vacuum drying technology were used to preparation of dehydrated cherry tomatoes, in order to shorten the drying time, improve nutrition and appearance quality of cherry tomato dehydration products. The drying process water, vitamin C, color, bulk density, rehydration ratio and sensory score for the experimental determination of indicators by single factor experiment and orthogonal design study to determine the freeze-dried pre-drying and microwave vacuum dehydration subsequent drying The conversion of water points and technology parameters. The results show that the combination of small tomatoes dried best technical parameters: 70°C under blanching pretreatment 60s, and then at -53℃ under vacuum freeze-drying12h, last in microwave power 6kW, temperature dry conditions at 55°C for 200s. Under this condition, the loss of vitamin C of the resulting products was 33%, the rehydration ratio of 4.79, shrinkage ratio of 0.63, close to vacuum freeze-drying effect of their sensory quality and nutrients, combined drying can greatly save the drying time and reduce energy consumption.
Keywords Cherry tomatoes; Vacuum freeze-drying; Vacuum microwave drying; Combined drying