红枣采后褐变机理及干燥动力学研究

Dates is largest acreage of fruit products in XinJiang, baking is a main method to the further processing of dates. This project is aimed at baking products after the bitter taste is easy, energy consuming, taking Xinjiang main cultivated varieties of Jun jujubes as main material, using different harvest period (white ripe period, crisp ripe period, mature period,postripeness period I,postripenessII), research in low-temperature storage and different drying methods ( freeze drying, hot-air drying, microwave vacuum drying ) conditions, the nutritional quality of Jun-dates ( quality index ) and browning mechanism ( determination of anthocyanins and related enzyme ). Microwave vacuum drying characteristics of Jun-dates fumble, to compare the influence of different drying parameters on drying and puffing characteristics, law process on the change of date slices of cyclic adenosine monophosphate content, water loss rate and texture of dry red dates, carries on the discussion to the storage and drying process of browning mechanism, research dried during Jun-dates piece suit glycosides, browning enzymes ( PPO enzyme ) activity dynamics, analysis of effects of the experimental factors and their interaction on the drying time and quality, the browning mechanism, construction of water and enzyme kinetics in the drying process model. As Jun-dates harvest and drying of industrialization and provide a theoretical basis.

红枣是新疆种植面积最大的林果产品，烘制是红枣目前深加工的主要方法。本项目针对烘制产品后味易苦，能耗高等缺点，以新疆主栽品种骏枣为研究试材，通过研究不同采收期（白熟期、脆熟期、完熟期、后熟期一、后熟期二）红枣采后贮藏条件和干燥方式（冷冻干燥、热风干制、微波真空干燥）对骏枣的营养品质（品质指标测定）和褐变机理（花色苷及相关酶测定）的变化情况。摸索骏枣微波真空干燥特性，比较不同干燥工艺参数对干燥及膨化特性的影响，研究干制工艺对枣片环磷酸腺苷含量、失水速率和质构的变化规律，对红枣贮藏和干制过程褐变机理进行探讨，研究干制期间骏枣枣片花色苷、褐变相关酶（PPO酶）活性动力学，分析各试验因素及交互作用对干燥时间和品质的影响规律，初步阐述褐变机理，构建干燥过程中水分和酶动力学模型。为骏枣采收及干制工业化提供理论基础。

以新疆主栽品种骏枣为研究试验材料，比较了低温贮藏条件下（0℃）和干制方式（冷冻干燥、热风干制和微波真空干燥）对不同采收期骏枣营养品质指标及褐变情况（花色苷和相关酶）的影响。比较了热风干燥、冷冻干燥和微波真空干燥三种不同干燥方式、分析切片厚度、微波功率、真空度和初始含水量对干燥速率的影响。初步构建干燥动力学数学模型，评价了红枣干制过程中花色苷及相关酶类变化，初步探索了微波真空干燥红枣褐变机理。.