国内外拉伸型干酪的种类及研究进展

概述了拉伸型干酪的种类、工艺,以及国外拉伸型干酪的研究进展.同时研讨了我国少数民族传统拉伸型干酪-乳扇的生产历史、工艺、研究情况,以及与国外传统拉伸型干酪的比较;并介绍了国内对Mozzarella干酪的研究进展.     

比萨干酪工艺及其功能特性分子基础

阐述了乳中的酪蛋白胶束如何经过生产和成熟逐步形成比萨干酪的微观结构,以及该结构如何影响干酪的功能性如融化性、拉伸性、出油性和起泡性.并应用上述分子理论分析省略热烫拉伸、混合酸化、添加钙等生产实例,说明生产工艺是通过作用于干酪的微观结构而影响其功能特性.本文在力图澄清国内比萨干酪生产中一些疑惑的同时,说明只有从认识干酪的分子基础入手,才可能通过控制工艺条件改善干酪的功能特性或提高生产的经济性.     

去乳糖牛乳制作莫扎瑞拉干酪的化学成分和感官特性研究

研究了去乳糖牛乳制作的莫扎瑞拉干酪.为进行比较研究,同时制作了含乳糖的天然牛乳制成的莫扎瑞拉干酪.分析结果显示不同牛乳制成的干酪,其化学成分相同.与此相反,感官特性则有所不同.尤其是传统的莫扎瑞拉干酪比无乳糖的莫扎瑞拉干酪总体的可接受性明显较强.不过在所有存储时间条件下,感官测试小组认为两种干酪的口味均较好.根据测试结果,制作无乳糖的莫扎瑞拉干酪可以为乳糖不耐症的人群提供饮食选择.     

Mozzarella干酪的加工及功能性

详述了莫扎瑞拉干酪的加工工艺,工艺参数,操作要点和质量控制.并对莫扎瑞拉千酪的功能性进行了分析.其寿命受融化性、拉伸性、褐变性、出油性等影响,而莫扎瑞拉干酪的功能性又受其水分、干物质中的脂肪、拉伸凝块水分、贮藏温度所决定.     

干酪质地及流变学特性的研究进展

介绍了有关干酪的成分及工艺过程对质地和流变学特性影响的研究。在干酪成分中，蛋白质是影响产品流变学特性的主要因素，酪蛋白空间形成的网状结构构成了干酪流变学的基础。在加工过程中，pH、温度、钙浓度、蛋白水解等所有对干酪成分分子产生变化的因素都可能使干酪的流变学特性和质地发生变化。因此，干酪流变学特性的研究对更好地控制质地，生产出质优价廉的干酪，具有重要的意义。最后，研究状况进行了展望。     

莫兹瑞纳干酪的加工工艺

比萨饼上厚厚的干酪做为这种西方馅饼的主料即为莫兹瑞纳干酪(Mozzarella).这种干酪与蔬菜、肉类等布满在圆形面团上,烘烤后就制得了金黄酥皮、馅鲜味美的比萨饼.这种专用干酪的开发在我国还属空白.本厂利用1987     

软质干酪工艺研究

研究了软质干酪的加工工艺结果表明，含脂率为3.2％的鲜牛乳，经75℃，15min杀菌冷却后接种体体积分数为1％的乳酸菌(V(保加利亚德氏乳杆菌)：V(嗜热链球菌)=2：3)并于32℃发酵40min，调节酸度至pH值为6．0，再依次加入质量分数为0．02％的CaCl2和质量浓度为2g／L牛乳的凝乳酶(m(小牛皱胃酶)：m(毛霉凝乳酶)=3：1)，恒温(32℃)发酵约1h，最后经切割、升温、搅拌、排乳清、撒盐、成熟等工艺制备出一种软质、质地良好、奶香浓郁相对价格较低的软质干酪。     

类Cheddar豆乳干酪工艺参数的优化

研究了类Cheddar豆乳干酪的生产工艺并对其工艺参数进行了优化,对影响产品质量的主要因素进行了研究。通过正交试验,对发酵剂、豆乳、凝乳酶、CaCl2的最适添加量、凝乳时间和凝乳效果进行了研究和探讨。结果表明,添加豆乳20%、发酵剂3%、凝乳酶0.03%(活力为9 000 u/g)、CaCl20.06%时凝乳效果较好,在质构上与纯牛乳Cheddar干酪无明显差异。     

比萨干酪的加工工艺

描述了以鲜牛乳为主要原料加工制作比萨干酪的加工工艺,主要包括原料乳杀菌、添加菌种、凝乳、切割、排乳清、热烫拉伸、盐渍等7步,也是比萨干酪加工的主要控制点。     

干酪产品的营养保健作用及其消费情况

本文对干酪和乳清产品的营养保健作用进行了阐述,提出牛奶深加工产品乳清蛋白和干酪是未来小康社会的健康蛋白质来源,大力发展干酪产品的生产和消费可以促进奶业的健康发展、增加奶农的收入,提高奶源质量,减少竞争的“同质化”,为消费者提供营养健康的奶制品。目前干酪和乳清的加工设备和技术以及技术人才可以在国内自主解决,不用一味依靠和进口国外昂贵的设备和加工技术,同时自主研发的干酪工艺和设备可以降低生产成本,提高产品的附加值,促进奶业良性循环发展。     

Mozzarella干酪提取液的抗菌活性

Mozzarella干酪中酪蛋白抗菌肽对人体有非常重要的作用。为了研究酪蛋白提取液的抑菌作用,对成熟期为40 d、50 d和60 d的Mozzarella干酪,分别用无菌蒸馏水、醋酸-醋酸钠缓冲溶液和TCA提取法制备干酪提取液,探讨了干酪提取液对大肠杆菌、枯草芽孢杆菌、酵母菌和黑曲霉的抑制作用。结果显示,不同成熟期Mozzarella干酪的提取液对大肠杆菌、枯草芽孢杆菌和酵母菌均有一定的抑制作用。成熟期为40 d的Mozzarella干酪,用无菌蒸馏水提取出的提取液对大肠杆菌的抑菌性最强;成熟期为60 d的Mozzarella干酪,用TCA提取法提取出的提取液对枯草芽孢杆菌、酵母菌和黑曲霉的抑菌性最强。     

Application of an antimicrobial packaging material from chicken bone gelatine and cinnamon bark oil to mozzarella cheese

Chicken bones are mostly discarded even though they contain a considerable amount of proteins, which would allow them to be applicable as a protein film source. In this study, chicken bone gelatine (CBG) films were prepared and characterised after the addition of cinnamon bark oil (CBO) to confer antimicrobial activity. The incorporation of 1% CBO increased the tensile strength of the CBG film from 18.2 to 23.9 MPa, whereas elongation at break was decreased from 15.6% to 5.91% and water solubility from 88.9% to 62.2%. Antimicrobial activity of the CBG films against foodborne pathogens as well as their antioxidant activity increased with the increase in CBO concentration. When CBG film containing 1% CBO was used for wrapping mozzarella cheese inoculated with Listeria monocytogenes, the population of the bacterium decreased after 20 days in storage, indicating that CBG films can be applied for improving the microbiological safety of mozzarella cheese.     

An approach to improve the baking properties and determine the onset of browning in fat-free mozzarella cheese

Compared with low-moisture part-skim mozzarella and mozzarella cheese, bake performance of low-fat and fat-free mozzarella on pizza has a lot to desire. We hypothesized that a water-soaking pretreatment step of low-fat and fat-free cheese shreds before baking would improve pizza baking performance. The study also examined the correlation of the onset of cheese browning with the rate of moisture loss, changes in cheese surface temperature, and 3-dimensional (3D) plot L* a* b* CIELAB color analysis. The pretreatment of soaking cheese shreds in water improved the baking properties of fat-free mozzarella cheese on pizza. Compared with the control sample, which demonstrated significant shred identity, poor shred melt, fusion, and stretch during a pizza bake with fat-free mozzarella, the soaked cheese (SC) sample demonstrated satisfactory cheese melt, fusion, and stretch. In addition, the SC sample had desired browning as opposed to the control sample's excessive browning. The additional moisture from the soaking pretreatment aided in delaying the onset of cheese browning in the SC sample when compared with the control sample. For both the control and SC samples, there was a strong correlation between the onset of cheese browning with the peak of moisture-loss rate, and an increase in cheese surface temperature (>100°C). The color analysis of the 3D plot confirmed the relationship between the onset of cheese browning and the shift in L* (lightness), a* (red-green color), and b* (blue-yellow) values. According to the study's findings, soaking cheese shreds before baking can help improve bake performance on pizza. Furthermore, 3 measurement tools used in the study, (1) moisture-loss rate, (2) cheese surface temperature, and (3) 3D plot CIELAB color, were useful in determining the onset of cheese browning and can be applied to different intervention strategies to control cheese browning during pizza baking.     

The inclusion of fresh forage in the lactating buffalo diet affects fatty acid and sensory profile of mozzarella cheese

The aim of this study was to determine the effect of inclusion of fresh forage in diet for lactating buffalo on properties of mozzarella cheese under intensive farming conditions. Thirty-two buffalo cows were equally allotted into 2 groups fed diets with (fresh group, FRS) or without (control group, CTL) fresh sorghum. The study consisted of 2 trials. In the first one, animals from group FRS were fed a diet containing 10 kg of fresh sorghum (10-FRS diet) that was doubled to 20 kg (20-FRS diet) in the second trial. All diets were isonitrogenous and isoenergetic, and fresh forage accounted for 13.4 and 26.5 of dietary dry matter, respectively, for the 10-FRS and 20-FRS diet. In each trial, milk from the 2 groups was used to produce 3 batches/diet of Mozzarella di Bufala Campana Protected Designation of Origin cheese. Milk yield and composition were not influenced by dietary treatment. The use of 10-FRS diet did not affect any properties of mozzarella. As the inclusion rate of fresh sorghum doubled to 20 kg, an increment of unsaturated fatty acid percentages and a lowering of short-chain and saturated fatty acids were observed. Moreover, the sensory characteristics of mozzarella were modified, although no effects were observed on consumer acceptance. We conclude that the use of green fodder can represent a low-cost feeding strategy to improve the healthiness of buffalo mozzarella under intensive farming conditions with no detrimental effect on consumer blind acceptance.     

Effect of natural cheese characteristics on process cheese properties

Natural cheese is the major ingredient utilized to manufacture process cheese. The objective of the present study was to evaluate the effect of natural cheese characteristics on the chemical and functional properties of process cheese. Three replicates of 8 natural (Cheddar) cheeses with 2 levels of calcium and phosphorus, residual lactose, and salt-to-moisture ratio (S/M) were manufactured. After 2 mo of ripening, each of the 8 natural cheeses was converted to 8 process cheese foods that were balanced for their composition, including moisture, fat, salt, and total protein. In addition to the standard compositional analysis (moisture, fat, salt, and total protein), the chemical properties (pH, total Ca, total P, and intact casein) and the functional properties [texture profile analysis (TPA), modified Schreiber melt test, dynamic stress rheometry, and rapid visco analysis] of the process cheese foods were determined. Natural cheese Ca and P, as well as S/M, significantly increased total Ca and P, pH, and intact casein in the process cheese food. Natural cheese Ca and P and S/M also significantly affected the final functional properties of the process cheese food. With the increase in natural cheese Ca and P and S/M, there was a significant increase in the TPA-hardness and the viscous properties of process cheese food, whereas the meltability of the process cheese food significantly decreased. Consequently, natural cheese characteristics such as Ca and P and S/M have a significant influence on the chemical and the final functional properties of process cheese.     

The mozzarella cheese flavour profile: a comparison between judge panel analysis and proton transfer reaction mass spectrometry

Described in this paper is a comparison of results obtained in flavour profiling with two different approaches: classical sensory analysis and a novel instrumental technique. The mozzarella cheese flavour profile of seven different brands has been described by a sensory panel of eight judges. The same brands have been studied by means of proton transfer reaction mass spectrometry (PTR‐MS), a novel technique well suited for detecting volatile organic compounds (VOCs) down to the pptv level in air, without any need for sample concentration or trapping. The PTR mass spectra of the headspace of mozzarella samples held at 36 °C have been compared with the judge panel flavour profile. Multivariate statistical data analysis shows that the two methods perform comparable sample discrimination. Even though several questions are still open (definition of better instrumental parameters, improvements in sampling set‐up, spectral interpretation), the PTR‐MS technique appears to be a very promising method for the instrumental evaluation of the flavour sensory profile of food. This opens up new opportunities both in the control of quality and technological processes as well in the fundamental comprehension of the physiological processes of aroma perception. © 2000 Society of Chemical Industry     

A review on stringiness property of cheese and the measuring technique

This review paper provides a deep understanding of stringiness property in a cheese product. Stringiness is used to describe the extended continuous strand of a molten cheese, especially mozzarella cheese. Stringiness is often described quantitatively by stretch length, as well as qualitative definition which focuses on the dimension of strand and ease of extensibility. Very often, the scope of defining stringiness attributes is limited by the measuring techniques because a complete experimental setup is required to obtain information on both stretch quantity and stretch quality. Among the measuring methods, cheese extensibility rig stands out to be the best method to assess stringiness attribute of a cheese as it is an objective method. In addition, a detailed study on the molecular behavior and interactions among natural and imitation cheese components in delivering stringiness, and the challenges faced therein have been reviewed. Thus, the review provides a foundation for the development of vegan cheese or plant-based cheese with stringiness properties.     

Impact of the type of cooker-stretcher on chemical,rheological and microstructural properties of low-moisture mozzarella cheese analogue

In this work, we carried out the curd plasticisation of part-skim low-moisture Mozzarella cheese analogue (LMMCA) through a continuous dipping-arms cooker-stretcher or a batch twin-screw extruder. The chemical composition of LMMCA samples obtained with the two machines was not statistically significant. During refrigerated storage (8°C), samples processed with the cooker-stretcher showed higher hardness values and were slightly less proteolysed. Hydrolysis of para-casein proceeded at the same rate in LMMCA samples made with the two systems. We observed similar microstructures by confocal laser scanning microscopy. Under adopted processing conditions, both treatments allowed to obtain LMMCA samples with stable hardness values up to 50 days.