干酪质构与风味控制技术研究进展

干酪是富含蛋白质和钙的高营养价值乳制品,是发达国家的膳食主体,也是乳品科学研究的热点。干酪的质构与风味特征是评价干酪品质的综合指标,改善干酪的质构和风味,并解析其形成机制是干酪研究的重点与难点。本文通过分析原料乳质量,凝乳、成熟、盐渍、拉伸和浓缩工艺,以及低脂和低盐干酪加工技术等环节,全面解析了干酪质构与风味特征的影响因素。本文论述了如调控凝乳方式、利用辅助发酵剂加速干酪特征风味形成、基因修饰技术加速干酪成熟等关键控制技术,并提出了调节钙离子以精准调控凝乳、阐明体细胞对干酪质构和风味的影响等未来干酪科学研究方向,为我国干酪的品质改善和工业化提供参考。     

干酪加工技术浅述

干酪(cheese)俗称奶酪、芝士、由水、脂肪和蛋白质组成,是多种牛奶成份浓缩的精华,具有极高的营养价值,干酪包含了几乎所有的牛奶蛋白质、矿物质(钙、镁和磷)和溶于脂肪的维生素,干酪中的很多营养成份对人体的健康起着重要作用,特别是防癌和提高健康免疫系统方面。干酪是钙的重     

乳化盐对Mozzarella干酪功能特性的影响

针对Mozzarella干酪品质存在的缺陷,拟通过添加乳化盐来改善Mozzarella干酪功能特性.在Mozzarella干酪拉伸过程中分别添加1％、3％、5％的柠檬酸钠、焦磷酸钠,测定贮藏第21天干酪功能特性的变化.结果表明,添加乳化盐后干酪的硬度和粘聚性显著上升(P＜0.05),油脂析出面积显著增加(P＜0.05),干酪熔化性改善,其中添加3％的柠檬酸钠和焦磷酸钠后,熔化面积分别增加了37.58％和59.57％;干酪中钙离子含量下降,说明乳化盐通过螯合酪蛋白胶体,削弱了酪蛋白间的相互作用,从而改善了Mozzarella干酪的功能特性.     

我国果酒研究发展现状

综述果酒的主要成份、营养价值及保健作用,介绍葡萄酒、山楂酒、梨酒、沙棘酒等常见果酒的特点、营养价值及研究进展,总结果酒生产中制约其发展的重要因素,为我国果酒产业的研发提供理论参考。     

功能性低脂干酪发酵剂的优化

活菌数是功能性低脂干酪的重要指标,本文就发酵剂对功能性低脂干酪活菌数的影响进行了研究,旨在通过控制发酵剂种类及添加量而使干酪最终活菌数达到功能性食品的标准。通过对单因素试验和正交试验研究与分析,结果表明:选择嗜热链球菌、嗜酸乳杆菌(1∶1)两种菌混合发酵剂为最适发酵剂,混合发酵剂添加量为6%时,干酪活菌数能达到107CFU/mL,符合功能性低脂干酪的活菌数要求,能够获得较为理想的试验效果。     

禽蛋抗压特性测试机构设计及其系统开发

禽蛋具有很高的营养价值,是人们日常生活中重要的动物性营养食品之一。研究禽蛋的抗压特性对禽蛋的流通、提高商品性、增加收益和促进家禽业的发展都具有十分重要的经济与社会意义。为此,设计了一种借助微机控制来实现禽蛋抗压特性的测试系统,利用该系统能够实现检测数据的接收、显示、保存及检测报表打印、数据维护等功能。     

莼菜贮藏保鲜的研究进展

莼莱是原产于我国的一种珍稀水生蔬菜,具有极高的营养价值和生理功能。本文主要就与莼菜贮藏品质相关成分、莼菜贮藏保鲜技术和影响贮藏品质的因素等方面展开综述和分析,并指出存在的问题及莼菜产业今后发展的趋势和研究方向。     

热激修饰瑞士乳杆菌对Cheddar干酪成熟的影响

研究了瑞士乳杆菌Lactobacillus helveticus 6024经热激修饰后,与干酪成熟相关的生化性质变化及其对Cheddar干酪成熟的影响。结果表明:瑞士乳杆菌经70℃、10 s的热激处理后,在10%脱脂乳中经32℃、6 h培养后,其产酸能力仅为6.4%,而与干酪成熟密切相关的平均氨肽酶活力,仍有约25%的保留。热激处理后的菌株加入到干酪中对其组分没有显著影响,但对干酪可溶氮水平有不同程度的影响。与未添加热激菌株的干酪对照组相比,总可溶氮含量增加不显著,而在成熟3个月时5%磷钨酸可溶氮占总氮比例增加2倍,组间差异显著。干酪质构、微观结构分析的结果也证明,热激修饰菌株对促进干酪成熟具有促进作用。     

油葵收获机械研究现状及发展建议

油葵是我国5大油料作物之一，其利用价值和营养价值高，被称为21世纪的“健康营养油”。我国油葵机械化收获水平不高，研制油葵收获机械对降低人工劳动强度、提高生产效率及实现油葵生产机械化具有重要意义。阐述了国内外油葵收获机械的研究现状，分析国内油葵收获机研制存在的问题，提出了发展建议。      

我国乳品工业发展存在的问题及对策

乳制品行业的发展是关系到人民健康和国民经济发展的重要产业,并成为我国农业中发展最快和增长性最好的产业之一。随着中国经济的持续、稳步、快速发展,老百姓的健康意识、对奶产品营养价值的认识及消费水平有了很大提高,乳品正成为人们每天生活必需品。但是,目前乳制品行业却存在着一系列的问题,严重制约着我国乳制品行业的发展。     

Overland water and salt flows in a set of rice paddies

Cultivation of paddy rice in semiarid areas of the world faces problems related to water scarcity. This paper aims at characterizing water use in a set of paddies located in the central Ebro basin of Spain using experimentation and computer simulation. A commercial field with six interconnected paddies, with a total area of 5.31 ha, was instrumented to measure discharge and water quality at the inflow and at the runoff outlet. The soil was classified as a Typic Calcixerept, and was characterized by a mild salinity (2.5 dS m⁻¹) and an infiltration rate of 5.8 mm day⁻¹. The evolution of flow depth at all paddies was recorded. Data from the 2002 rice-growing season was elaborated using a mass balance approach to estimate the infiltration rate and the evolution of discharge between paddies. Seasonal crop evapotranspiration, estimated with the surface renewal method, was 731 mm (5.1 mm day⁻¹), very similar to that of other summer cereals grown in the area, like corn. The irrigation input was 1874 mm, deep percolation was 830 mm and surface runoff was 372 mm. Irrigation efficiency was estimated as 41%. The quality of surface runoff water was slightly degraded due to evapoconcentration and to the contact with the soil. During the period 2001–2003, the electrical conductivity of surface runoff water was 54% higher than that of irrigation water. However, the runoff water was suitable for irrigation. A mechanistic mass balance model of inter-paddy water flow permitted to conclude that improvements in irrigation efficiency cannot be easily obtained in the experimental conditions. Since deep percolation losses more than double surface runoff losses, a reduction in irrigation discharge would not have much room for efficiency improvement. Simulations also showed that rice irrigation performance was not negatively affected by the fluctuating inflow hydrograph. These hydrographs are typical of turnouts located at the tail end of tertiary irrigation ditches. In fact, these are the sites where rice has been historically cultivated in the study area, since local soils are often saline-sodic and can only grow paddy rice taking advantage of the low salinity of the irrigation water. The low infiltration rate characteristic of these saline-sodic soils (an experimental value of 3.2 mm day⁻¹ was obtained) combined with a reduced irrigation discharge resulted in a simulated irrigation efficiency of 60%. Paddy rice irrigation efficiency can attain reasonable values in the local saline-sodic soils, where the infiltration rate is clearly smaller than the average daily rice evapotranspiration.     

车用发动机润滑油失效规律与更换周期研究

研究在正常使用条件下１０Ｗ／３０－ＱＣ级润滑油用于某型车用发动机时所表现的失效规律,确认期服从两参数Ｗｅｉｂｕｌｌ分布,并给出分布的尺度参数η和形状参数ｍ之最佳线性无偏估计（ＢＬＵＥ）同时,还为定量分析,计算车用发动机润滑油的使用可靠性和合理确定其更换周期提供了一套可供借鉴的方法,并给出了具体的计算实例。     

农村剩余劳动力就业问题的探讨

论述了我国农村剩余劳动力就业的意义,并针对我国农村剩余劳动力的现状,提出多渠道促进农村剩余劳动力就业的途径和办法。     

乡（镇）农业技术推广体系存在的问题及对策

乡（镇）农技推广体系是农业发展的关键。介绍朝阳市农业技术推广体系的现状,针对目前体制及运行机制、服务手段等方面存在的问题,提出适合朝阳市乡（镇）农技推广体系改革与发展的对策,以期对全省农技推广体系改革和发展起到一些借鉴作用。     

草莓的采收与贮藏

草莓果味酸甜爽口,营养价值高,为人们所喜爱的应市鲜果之一。由于草莓易受损伤和微生物侵染,因此其采收、贮藏过程极为重要。介绍草莓采收过程中的注意事项以及11种贮藏保鲜技术的实施步骤和操作方法,推介9种加工方式,为草莓产业化提供技术支持。     

金谷子耐旱TG118引种试种及推广应用

对引进的谷子新品种金谷子耐旱TG118进行品种比较试验和多点试种。结果表明：该品种抗旱、耐瘠、适应性强,稳产、高产、抗病抗风抗倒伏强,品质优良,粮草兼用,种植简单,省工易管;一般产量在6000kg/hm2以上,比当地主栽品种增产20%以上。最高产量达9450kg/hm2,适于在辽西北地区推广应用。     

对《种子法》存在问题的探讨

《种子法》是我国种植业第一部法律。自实施以来,为依法加强种子管理提供了有力的法律支撑,促进我国种子产业发生翻天覆地的变化。但随着依法管理工作的深入和种子产业的快速发展,《种子法》及配套规章的一些问题逐步显现出来。对《种子法》及配套规章存在的问题进行深入分析,对需要进一步补充的章节以及需要调整的内容进行深入探讨,以求更加完善和明确。     

瓦房店市水果生产标准化发展研究

瓦房店市是我国重要的水果生产基地,在国内水果生产领域占有重要地位。随着水果市场化的不断深入,如何满足和适应国内外市场需求成为瓦房店市水果生产的关键问题。从瓦房店市水果生产实际出发,阐述了实施水果生产标准化的必要性,提出了发展水果生产标准化的具体措施。     

和谐社会理论建设的几点哲学思考

在新世纪,面对机遇和挑战,党的十六大把“社会更加和谐”作为全面建设更高水平的小康社会的一个重要目标。中国人素有社会和谐的理想;西方人自古也向往社会和谐;借鉴东西方两种和谐社会思想的经验、教训,构建社会主义和谐社会理论。     

Quantifying the sustainability of agriculture

The rural sustainability index is a scientifically based tool to quantify the performance of agriculture. The sustainability of crop production is quantified from three perspectives; people, planet and profit. Within each perspective, one condition was selected that must be met to warrant agriculture. These are: No hazardous work should be used within the crop production chain; agricultural crops should not be grown on land allocated to nature by national law or regulations and, when a GM-crop is present or is introduced in a region, it should not harm development opportunities of other farmers. If these excluding conditions are met, the sustainability of agriculture is assessed through five performance indicators on school attendance, water use and consumption, fertilizer use, pesticide use, and farm income. For each of the five indicators, critical values and target values have been given that limit the transition range between non-sustainable and sustainable production. The five indicators are combined into a sustainability index. The index aims at improving the socio-economic position of farmers while protecting the environment.