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.     

量化筛选中国水牛奶生产Mozzarella干酪所需发酵剂

为了获得水牛奶Mozzarella干酪生产发酵剂所需菌种及其配比和用量的最佳方案,以自行筛选的保加利亚乳杆菌、嗜热链球菌、乳酸乳球菌、干酪乳杆菌为素材进行研究.通过检测所得水牛奶Mozzarella干酪样品的10项质量参数,对参数统计处理分析得到量化筛选结果,发现同时选用4个菌种、以相同的比例和3.0％的总添加量作为发酵剂制作的中国水牛奶Mozzarella干酪品质较优.     

不同发酵剂对Mozzarella干酪品质的影响

采用嗜热链球菌和嗜热乳杆菌作为Mozzarella干酪的发酵剂，研究单一嗜热链球菌发酵剂与嗜热链球菌和嗜热乳杆菌组成的混合发酵剂对Mozzarella干酪品质的影响。结果表明，混合菌作发酵剂制得的干酪品质优于用单一嗜热链球菌作发酵剂的干酪。     

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.     

水牛乳辣味适度成熟干酪的研制

通过对比不同成熟温度下,干酪成熟过程中硬度、弹性、微观结构、可溶性氮、感官评价等差异,研制一种水牛乳辣味适度成熟干酪,结果表明4℃下成熟90 d,8℃下成熟75 d,12℃下成熟60 d,均可获得品质良好的产品,干酪质地均匀,具有较浓郁的酸辣味、柔和的发酵风味。     

水牛乳—豆乳混合干酪胚的制备

以干酪凝乳情况、校正产率、质地及感官为评价指标,优化水牛乳-豆乳混合干酪胚的制备工艺,结果表明:当豆乳添加量为15%,程序升温速度为1℃/5min升温至40℃、1℃/2min升温至45℃,可得到凝乳时间短、凝乳情况良好、干酪质地适中、校正产率较高、感官评价好的新鲜干酪胚。     

新鲜辣味水牛乳干酪制备工艺的研究

采用单因素以及正交实验,以干酪产率及感官评分为评价指标,对新鲜辣味水牛乳干酪制备工艺进行优化。结果表明,最佳工艺为:杀菌条件65℃,30 min,菌种添加量3%,凝乳酶添加量0.0015%,辣椒酱添加量2.5%。     

Cheddar干酪附属发酵剂筛选及其应用

为了筛选能够促进Cheddar干酪成熟,从泡菜、腐乳及不同产地的Cheddar中筛选具有高肽酶活力和自溶度的乳杆菌作为Ched-dar干酪附属发酵剂,并应用于Cheddar干酪的制作中.结果表明,从美国Cheddar干酪中筛选出1株Lactobacillus plantarum OD具有较高的肽酶活力和自溶度,运用于Cheddar千酪的制作中能显著提高其游离氨基酸浓度,改善其风味,有利于加快干酪的成熟.     

水牛乳成分、理化特性及其干酪产品研究进展

水牛乳比普通牛乳营养价值高,乳汁浓厚,素有“奶中极品”之称。然而水牛乳产量低,原料价格是普通牛乳的3倍左右,从而导致相关产品市场疲软问题。因此,提高水牛乳附加值是解决水牛乳发展的主要途径之一。文章对水牛乳成分、理化特性、干酪加工特点等方面进行综合分析,结果表明,由于水牛乳干酪的高产出率、高营养价值、高品质以及特殊的质构特性,更适合制作干酪产品,尤其是Mozzarella干酪。我国市场上有关水牛乳Mozzarella干酪产品还很少见,作为一类高级营养水牛乳食品,将在未来乳品领域有很大的发展空间。     

辅助发酵剂加速Provolone干酪成熟的研究

将瑞士乳杆菌6024作为辅助发酵剂添加到Provolone干酪中,加速Provolone干酪成熟,研究了其对干酪游离氨基酸、游离脂肪酸、质构特性、电镜、风味物质的影响。结果表明,瑞士乳杆菌6024作为辅助发酵剂对干酪中游离脂肪酸质量分数没有显著影响,但能显著增加干酪游离氨基酸质量分数,60 d时达到对照组90 d时的质量分数,此时干酪的质构特性、微观结构、风味物质与对照组90 d时差异不显著。由此可知,瑞士乳杆菌6024作为辅助发酵剂可加速Provolone干酪的成熟,缩短成熟时间。     

Effects of Starter Culture and Coagulating Enzymes on Viscoelastic Behavior and Melt of Mozzarella Cheese

ABSTRACT: Mozzarella cheeses were made with a single culture (SC) or a mixed culture (MC) using 1x or 6x of cheese coagulants chymosin or Cryphonectria parasitica (CP). Melt area increased only by approximately 80% in cheeses made with SC against 230% in the cheeses made with MC after 30 d of storage. Soluble nitrogen was also higher in MC cheeses as compared to SC cheeses. Both the elastic (G') and the viscous (G") modulus decreased with storage. Decrease in both moduli was greater in the MC cheeses at 6× enzyme level compared to SC cheeses at 1× enzyme level. The synergism between coagulating enzyme and starter culture was beneficial, which improved melt and flow of Mozzarella cheese and had profound effects on the viscoelastic properties of Mozzarella cheese.     

Sensory Changes During Ripening of Raw Ewes' Milk Cheese Manufactured With and Without the Addition of a Starter Culture

ABSTRACT: This study characterizes and compares the sensory aspects of raw ewes' milk cheeses manufactured with and without the addition of a starter culture using specifically developed sensory terminology. Furthermore, overall organoleptic quality was assessed at each ripening stage. Two different raw ovine milk cheese batches were manufactured with and without the addition of a freeze-dried starter. Sensory differences in odor, flavor, and texture were related to starter and raw milk flora activities during manufacturing and ripening. Cheeses made with the addition of a starter culture were scored higher by quality experts. Cheeses manufactured without a starter culture received higher scores for dirty and animal attributes, such as rennet, butyric, sharp, pungent, and brine, possibly related to lower quality scores. Conclusions reached in the present study coincide with previous ones; however, by using a sensory lexicon specifically developed for ewes' milk cheeses, it has been possible to describe slight and specific differences in the cheeses.     

发酵剂、氯化钙及凝乳酶添加量对白牦牛乳Mozzarella干酪质构的影响

以白牦牛乳为原料制作Mozzarella干酪,在单因素试验基础上采用Box-Behnken响应面法对发酵剂、CaCl_2、凝乳酶添加量进行优化,利用质构综合评分筛选最佳的工艺参数。结果表明,白牦牛乳Mozzarella干酪的最佳工艺参数为:发酵剂添加量0.24 g/L、CaCl_2添加量0.23 g/L、凝乳酶添加量0.04 g/L,此时白牦牛乳Mozzarella干酪质构综合评分为11.095,出品率为20.53%,感官评分为93.67。此工艺条件下制作的白牦牛乳Mozzarella干酪香味浓郁,质地均匀,软硬适度。     

甲醇芽孢杆菌凝乳酶对马苏里拉干酪加工特性的影响

为了探究甲醇芽孢杆菌（Bacillus methanolicus）凝乳酶在马苏里拉干酪加工中的应用,分别以使用甲醇芽孢杆菌凝乳酶、混合酶制剂（含质量分数10%甲醇芽孢杆菌凝乳酶和90%商品凝乳酶）制作的马苏里拉干酪作为实验组,以商品凝乳酶干酪作为对照组,测定不同组别干酪成熟期间的蛋白水解特性、质构、风味和微观结构变化,研究甲醇芽孢杆菌凝乳酶对马苏里拉干酪加工特性的影响。结果表明,实验组干酪在成熟过程中pH值（4.6～5.3）、微生物数量（8.80～9.68（lg（CFU/g）））与对照组无显著差异（P＞0.05）;实验组干酪水分质量分数（混合酶干酪为（43.21±1.17）%、甲醇芽孢杆菌凝乳酶干酪为（46.15±0.94）%）均显著高于对照组（（41.08±1.04）%）,得率（混合酶干酪为（9.27±0.17）%、甲醇芽孢杆菌凝乳酶干酪为（9.46±0.16）%）也显著高于对照组（（8.98±0.13）%）（P＜0.05）;且实验组干酪的蛋白水解特性（pH 4.6时可溶性蛋白、酪蛋白水解程度和游离氨基酸质量分数）以及风味物质种类和相对含量等指标也优于对照组干酪。但是实验组中甲醇芽孢杆菌凝乳酶干酪保形性相对欠佳,感官评定得分偏低,混合酶干酪与对照组质构及感官基本得分一致,因此甲醇芽孢杆菌凝乳酶可以作为商品酶的部分代替品应用于干酪的生产中。     

钾盐替代和附属发酵剂对切达干酪品质的影响

为明确降低钠含量和添加在脱脂乳中表现出具有较高血管紧张素转换酶（angiotensin-converting enzyme,ACE）抑制率的Lactobacillus paracasei M3作为附属发酵剂对切达干酪理化性质和体外抗高血压潜力的影响,将部分钾盐替代和L. paracasei M3单独和混合加入到干酪与空白组作对照,以主要成分、微生物、蛋白水解度、质构和风味为理化指标和以ACE抑制率为体外抗高血压潜力指标。结果表明,4 组干酪的主要成分差异不大（P＞0.05）,钾盐替代组、L. paracasei M3组、钾盐替代和L. paracasei M3混合组干酪在乳酸菌总数、pH 4.6可溶性氮、总游离氨基酸上显著高于空白组干酪（P＜0.05）,但是降低了干酪的硬度、pH值和有明显的苦味（P＜0.05）,而在体外抗高血压潜力方面,3 组干酪在成熟6 个月之后ACE抑制率达65.2%、74.3%和78.7%,比空白组分别高19.6%、36.2%和44.4%,由此可知,在切达干酪中钾盐替代和添加L. paracasei M3有助于具有抗高血压潜力的ACE抑制肽的产生,但是后续需要对风味进行补偿性研究。     

发酵剂对牦牛乳硬质干酪蛋白降解和苦味关系的影响

用甘肃天祝新鲜牦牛乳为原料分别添加嗜温、嗜热和混合发酵剂制作硬质干酪,以pH 4.6-可溶性氮（soluble nitrogen,SN）、12%三氯乙酸氮（trichloroacrtic acid-N,TCA-N）、游离氨基酸（free amino acid,FAA）含量和疏水性肽/亲水性肽（S/Q）为蛋白水解度指标,研究3 种牦牛乳硬质干酪在6 个月内成熟过程中苦味和蛋白质降解之间的关系。结果表明：3 种干酪在成熟过程中pH 4.6-SN、12% TCA-N和FAA含量均呈上升趋势,苦味值与pH 4.6-SN、12% TCA-N和FAA含量成正相关,相关系数分别为0.400、0.412和0.458。3 种干酪成熟过程中S/Q的变化趋势和程度不同,嗜温发酵剂干酪中S/Q呈现降低趋势;嗜热和混合发酵剂干酪中S/Q均呈现先降低后增大的趋势,但在这两种干酪中S/Q的变化程度不同,嗜热发酵剂干酪在1～3 个月S/Q略有降低,在3～6 个月S/Q快速增大,而混合发酵剂干酪正好相反。S/Q与苦味值成极显著正相关（r=0.895）,S/Q可很好地反映干酪中苦味的强弱。而干酪中苦味强弱与蛋白质降解强弱密切相关,对蛋白降解程度越大的发酵剂制作的干酪越容易产生苦味,其中,嗜热发酵剂对干酪蛋白降解程度最大,混合发酵剂次之,嗜温发酵剂最小。     

功能性棉型织物服用性能的模糊综合评判

研究功能性棉型织物综合服用性能优劣的模糊评价方法。对几种不同规格的功能性棉型织物的透气量、悬垂系数、折皱回复角、回潮率、透湿量、芯吸高度等性能进行了相关测试,采用模糊数学综合评判方法对测试数据进行处理分析,通过对权系数和标准化值的计算求算出综合评判值,得到了功能性棉型织物综合服用性能优劣的排序。指出:利用此分析过程对织物整体性能进行评估,既兼顾到织物的综合服用性能,又考虑到各性能权重分配上的差异,分析方法简单、合理、可靠,且评判结果较好。     

新疆地区驴乳源优良乳酸菌发酵剂的筛选及菌株益生特性

从新疆哈密地区的15个驴乳样品中分离筛选出38株疑似乳酸菌,其中7株菌具有明显凝乳特性.经16S rRNA基因测序鉴定为乳酸片球菌(Pediococcus acidilactici)HL12-21、戊糖片球菌(Pediococcus pentosaceus)HL29-5、蒙氏肠球菌(Enterococcus mundt...     

棉Coolmax异纬织物服用性能的模糊综合评判

探讨棉Coolmax异纬织物的服用性能.以9种棉Coolmax异纬织物为例,经纱均为JC 9.7 tex纱,采用经碱减量处理的Coolmax 7.6 tex纱和未经碱减量处理的Coolmax 8.3 tex纱与JC 9.7 tex纱按不同的组合作纬纱,测试了这9种织物的透气性、透湿性、悬垂性、导电性、折皱回复性和毛细效应.采用模糊综合评判方法对测试数据进行处理分析,得到了9种织物综合服用性能的优劣排序.认为:碱减量处理可以改善棉Coolmax异纬织物综合服用性能.     

Detection of Clostridium Tyrobutyricum in Milk to Prevent Late Blowing in Cheese by Automated Ribosomal Intergenic Spacer Analysis

Clostridium tyrobutyricum has been identified as the main causal agent of the late blowing defect in cheese, with major effects on quality and commercial value. In this work, for the first time, we applied automated ribosomal intergenic spacer analysis (ARISA) approach to diagnose the presence of C. tyrobutyricum in raw milk before cheesemaking. A species‐specific primer set was designed and used for this original application of the ARISA. Sensitivity of detection, reproducibility of the fluorescent PCR assay, and repeatability of the capillary electrophoretic analysis of amplicons were evaluated using DNA extracted from milk added with known amounts of C. tyrobutyricum genome copies, ranging from 3 × 10⁶ to 3. Results indicated that the sensitivity of the technique permits to detect the bacterium in all the samples. The reproducibility, evaluated by analyzing 3 sets of serial dilutions, resulted satisfactory, with little deviation within PCR reactions amplifying the same starting amount of template (standard deviations ≤ 0.1, coefficients of variation ≤ 3%). The peaks' fluorescence displayed an evident correspondence with the number of genome copies contained in each dilution. The capillary electrophoretic analysis, tested by running a single PCR product per dilution point in 10 repeats, resulted efficient and highly repeatable, with excellent coefficients of variation ≤ 2% and standard deviations ≤ 0.1 in all the sample sets. This application of ARISA gives good estimates of the total C. tyrobutyricum DNA content allowing a specific, fine‐scale resolution of this pollutant species in a complex system as milk. A further advantage linked to the automatization of the process.