食品冻干的预处理

影响冻干食品品质的因素有很多,其中预处理对制品的营养成分、色泽、香味有较大的影响,对制品的复水也有一定的影响。对冻干食品的预处理作了一般性的介绍,并主要介绍了猕猴桃、菠菜、大蒜的预处理工艺要点。     

大蒜冷冻干燥工艺研究

研究了冷冻干燥技术加工大蒜制品的生产工艺。采用电阻法测定出大蒜共晶点为- 1 8℃。通过单因素试验 ,探讨了不同加热温度对大蒜冻干时间的影响。经过研究冷冻干燥的最佳工艺为 :操作压力为 1 3 3～ 40Pa ,升华干燥温度控制在 - 2 0℃左右 ,隔板加热温度控制在 40℃。     

大蒜脱臭方法的研究进展

我国大蒜资源丰富,大蒜制品已广泛应用于各个行业,但是由于缺乏高品质的深加工大蒜产品,而丧失了市场竞争力.本文概述了大蒜的组成成分、重要有效成分蒜素的形成、分解机理以及大蒜制品的开发利用.并且总结了大蒜的脱臭机理以及不同脱臭方法的优缺点,以期为进一步研究、开发高品质大蒜深加工制品提供参考.     

大蒜及其制品影响致病菌活性的研究

以大蒜及大蒜制品对几种致病菌活性的影响为内容,进行了实验研究。通过对平均杀菌率统计显示,大蒜汁及大蒜制品对伤寒沙门氏菌、痢疾志贺氏菌、金黄色葡萄球菌有较强的杀灭作用,大肠杆菌的效果次之,对枯草杆菌和腊样芽胞杆菌有一定的抑制作用,3%的大蒜汁可有效的杀灭腊样芽胞杆菌。     

蒜苔冻干试验及其传热传质模型研究

确定了蒜苔冻干工艺条件，探讨了热烫温度及时间、预冻速率、干燥室及捕水器真空度和温度对制品品质与干燥时间的影响，描述了蒜苔冻干的传热传质模型并计算了蒜苔冻干时间。     

芦荟冻干及多糖提取研究

通过对库拉索芦荟、中华芦荟、木立芦荟进行真空冷冻干燥实验，得到了冻干曲线。以3种芦荟鲜叶和冻干制品及库拉索芦荟常压干燥、真空干燥制品为原料，分别进行多糖提取实验，结果表明，库拉索芦荟冻干制品多糖提取率最高。因此以库拉索芦荟冻干制品为原料，研究了用溶剂提取法提取芦荟多糖的最佳工艺条件。实验表明，水提醇沉法的最佳工艺条件为：料水比1：50，提取温度50℃，提取时间5h，提取次数1次，提取液浓缩至原体积的1／3，80％乙醇醇析。对芦荟叶片冷藏时间与多糖含量的变化做了初步研究。     

真空冷冻干燥黑大蒜粉的加工工艺

利用真空冷冻干燥技术将黑大蒜制作成黑大蒜粉。对黑大蒜粉真空冷冻干燥工艺做初步研究,得到黑大蒜粉成品的最佳工艺:大蒜与水料液比为1∶5进行打浆,大蒜浆装盘厚度为6mm,-18℃下预冻12h后冷冻干燥,冻干参数为加热温度60℃,真空度30~100Pa,时间20h。     

大蒜的抗菌作用及制品

本文综述大蒜的各种抗菌作用,并介绍大蒜的各种加工制品、为大蒜的综合开发利用提供科学依据。     

冻干制剂喷瓶现象分析

冻结的制品经真空升华脱水的过程称为冷冻干燥,简称冻干。冻干的固体物质由于微小冰晶体的升华呈多孔结构,并基本保持原来冻结时的体积,加水易再溶解,恢复原有的溶液状态。在生化制药中,冻干已广泛用于原料药和制剂的加工。 冻干的程序包括冻结、升华和再干燥。冻结是将制品的温度降低到共晶点以下,使     

大蒜和大蒜制品的化学组成

本文综述了:大蒜的化学组成;蒜味的组份、化学变化以及气味强度的测定方法;完整大蒜的含硫化合物;大蒜的酶以及酶促反应。并介绍了大蒜油、蒜素、脱水大蒜、蒜片、蒜粉、蒜汁和大蒜萃取物等主要大蒜制品。     

大蒜3种脱水加工工艺比较

目的探究热风干燥法、微波干燥法和冷冻干燥法对干燥大蒜品质的影响。方法测定3种干燥方法下大蒜的脱水率、复水率、色值以及能耗,运用SPSS统计进行分析。结果护色液对干燥工艺无影响;热风干燥的脱水率为46.41%,复水率为104.53%,色值为143.36;冷冻干燥的脱水率为71.44%,复水率为186.52%,色值为191.07;微波干燥的脱水率为54.46%,复水率为88.21%,色值为177.80。结论热风干燥、微波干燥和冷冻干燥对干燥大蒜品质的影响各有优缺点;冷冻干燥工艺最为理想,能耗最低,但是在设计工艺的生产过程成本最为昂贵,需要进一步改进。     

High hydrostatic pressure treatment for manufacturing of garlic powder with improved microbial safety and antioxidant activity

The traditional method of manufacturing garlic powder (GP) that includes simple grinding of air-dried garlic slices has problems of microbial safety and a pungent flavour for this product. Microbiologically safe GP with a less pungent flavour and better antioxidant activities was manufactured using high hydrostatic pressure (HHP), wet grinding and freeze-drying process. The numbers of total aerobic bacteria and yeasts and molds in untreated (without HHP) GP were 3.64 and 2.47 log CFU/g respectively. Garlic powder treated with 600 MPa HHP for 5 min exhibited a total aerobes count of 1.62 CFU/g and a yeasts and molds count of 1.43 log CFU/g. The diallyl disulfide content, which is responsible for the pungent odour of garlic, was also significantly reduced by HHP due to a decrease in the alliinase activity. Hence, a novel process using HHP can help to produce GP with improved microbial safety, flavour and nutrition.     

HACCP在出口真空冻干大蒜生产中的应用

探讨了HACCP在蒜片冻干生产中的应用，进行危害分析(HA)，确定关键控制点(CCP)，并制定了相应的控制极限，旨在防止微生物污染。应用该质量管理系统可最大限度地降低微生物污染，提高产品质量，同时将危害降至最低程度，避免造成经济损失。     

大蒜在我国的开发利用现状、存在问题及对策

对大蒜的营养价值、开发利用现状及存在问题概述，并就加速大蒜产业化发展提出了一些对策。     

Assessment of the Anti-Microbial Activity of Dried Garlic Powders Produced by Different Methods of Drying

The anti-microbial activity of a range of garlic products including dried garlic powder produced by different methods, commercial garlic products, and garlic oil was determined against a range of selected bacteria. The bacteria included food borne pathogens, spoilage agents, and health-beneficial agents, namely Staphylococcus aureus, Escherichia coli, Salmonella typhimurium, Bacillus cereus, and a mixed lactic culture consisting of Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophilus. The dried powders were produced using air-drying at both 60 and 80°C, vacuum-drying at 50 and 60°C, and freeze-drying at ?20°C. In addition, five commercial products were tested, two of which are used as spices, and three as food supplements. Before testing, the moisture content of the dried garlic powders was raised to that of fresh garlic before drying. Garlic oil was used without any addition of water. In general, the results showed that the lactic culture was the most sensitive to the growth inhibitory active compound of garlic used in this study, followed by Staphylococcus aureus. In contrast Salmonella typhimurium and Bacillus cereus demonstrated the greatest resistance to garlic. Generally, fresh garlic produced the greatest inhibition followed by freeze-dried powder. The anti-microbial activity decreased with decreasing dried garlic powder concentration. The results showed that both drying temperature and time have major effects on retaining the active components responsible for the inhibition of microbial growth. The anti-microbial substances in the moist fresh garlic were also affected by moist-heating temperatures and time. Higher heating temperatures caused faster loss of anti-microbial activity. The decrease in growth-inhibition zones for moist-heated fresh garlic followed zero-order kinetics.     

氢化物原子荧光法测定大蒜及其制品中的硒

目的：测定大蒜及其制品中硒的含量。方法：大蒜、蒜氨酸、蒜酶、大蒜多糖样品经过HNO3-HClO4湿法消解,采用氢化物原子荧光光谱法测定硒的含量。结果：大蒜、蒜氨酸、蒜酶、大蒜多糖中硒的含量分别为0.010～0.024、0.423～0.629、0.057～0.064、0.001～0.007μg/g。结论：该方法测定大蒜及其制品中硒的含量,操作简便,灵敏度高。     

山楂蒜蓉酱的研制

以新鲜大蒜和山楂果为主要原料,采用微波加热法、吸附法及掩蔽法相结合对大蒜进行脱蒜,并添加焦糖和食盐调色调味制成一种具有浓郁蒜香味的蒜蓉调味品。     

超声波处理对真空冷冻干燥香蕉片的影响

以真空冷冻干燥总时间和成品复水率为主要指标,采用超声波对香蕉片进行预处理,考察其对真空冷冻干燥香蕉片的影响。结果表明,超声波预处理可明显缩短冻干总时间和提高成品复水率,最优超声波预处理条件为功率140 W,处理时间40 min,频率28 kHz,此条件下的真空冷冻干燥总时间为8.9 h。     

番茄蒜蓉酱的研制

以新鲜大蒜和番茄为主要原料,采用酸烫法、吸附法及掩蔽法相结合对大蒜进行脱臭,并添加焦糖和食盐调色调味制成的一种具有浓郁蒜香味的蒜蓉调味品。