零添加高钙奶的研发

本文以法律法规为基础,通过稳定性分析和风味品尝实验,筛选出了比轻质碳酸钙和乳矿物盐更适合高钙奶的钙源——牛奶蛋白粉;确定了以牛奶蛋白粉为钙源,不添加稳定剂高钙奶的最适超高温瞬时灭菌条件为温度136℃、保持时间3 s,为行业开辟零添加高钙牛奶新品类奠定基础。     

不同钙剂对高钙奶稳定性的影响

研究了不同的钙剂及用量和不同的稳定剂对中性高钙奶稳定性的影响。结果表明，以碳酸钙为代表的电离度较小的分子钙，其电离产生的钙离子对体系的稳定性影响相对较小。因此，主要通过提高中性高钙奶的悬浮效果，可解决由于加入碳酸钙而引起的体系出现沉淀的问题；以乳钙为代表的有机分子钙，由于乳钙自身在水溶液中具有很好的分散性．且可能因其电离度较碳酸钙大，故而乳钙对中性高钙奶体系的影响主要是游离的钙离子与乳状液中界面上的乳蛋白通过桥连作用，引起体系絮凝，可通过加入螯合剂螯合体系的钙离子来解决。     

高钙奶含钙并不高

现在,很多人把牛奶当做自己或家人的日常饮品,天天饮用。因为大家都知道,牛奶是含钙量较高的饮品之一,且口感也易被大众接受,可以说是物美价廉。而钙对人体健康有诸多好处,比如,经常腰背酸痛和痛经的人补充钙质会改善症状;成长期神经痛的青少年多摄     

高钙奶苦味原因分析

通过有苦味的高钙奶样品中的细菌总数、蛋白质水解度、寡肽含量、游离氨基酸含量、蛋白酶活性等指标的测定,对高钙奶在保质期末出现苦味的原因进行分析。结果表明苦味高钙奶和无苦味牛奶样品中的细菌总数无显著差异(p≥0.05),苦味高钙奶中的寡肽、游离氨基酸含量,特别是苦味氨基酸含量显著高于无苦味牛奶样品(p<0.05),苦味牛奶样品中的蛋白酶活性显著高于无苦味牛奶样品(p<0.05),同时高钙奶中添加的碳酸钙和稳定剂中的蛋白酶也有较高活性。高钙奶苦味主要是由于牛奶中的内源或外源性蛋白酶水解酪蛋白,生成苦味的游离氨基酸、寡肽等造成的,针对这一原因,可通过提高原料乳和添加剂的卫生质量、控制生产加工过程中的卫生、调整和改进杀菌工艺等方法,以避免高钙奶的苦味问题。     

高钙奶中不同钙剂对其稳定性的影响

本文重点研究了钙强化剂的种类、不同用量和不同的稳定剂对高钙奶稳定性的影响.结果表明以碳酸钙为代表的电离度较小的分子钙,其电离产生的钙离子对乳状液体系的稳定性的影响相对较小,因此主要通过提高乳状液的悬浮效果,可解决由于加入碳酸钙而引起的体系出现沉淀的问题;以乳钙为代表的有机分子钙,由于乳钙自身在水溶液中具有很好的分散性,电离度较碳酸钙大,乳钙对高钙奶体系稳定性的影响主要是游离的钙离子与乳状液中界面上的乳蛋白通过桥连作用,引起体系絮凝,可通过加入螯合剂螯合体系的钙离子来解决.     

快速分析卡拉胶与结冷胶对高钙奶的稳定性影响

研究了卡拉胶及结冷胶对以碳酸钙为钙剂的中性巴氏高钙奶的稳定性影响。借助TURBISCAN Lab型分散稳定性分析仪进行稳定性快速分析,同时通过离心分离及传统观察分析法比较两种胶体的悬浮效果。传统观察结果表明,结冷胶在中性巴氏高钙奶中具有良好的悬浮稳定性,随着用量的提升,底部沉淀明显改善,卡拉胶悬浮效果不佳;而通过稳定性分析可以得出,卡拉胶及结冷胶对巴氏奶中的蛋白絮凝起到一定作用,随着用量提升,体系颗粒向下迁移,底部沉淀增加,对改善顶部浮油效果作用不大。     

“合诚”高钙奶稳定剂对高钙奶体系的稳定作用

全国第三次营养调查结果表明，我国居民缺钙现象比较普遍，利用高钙奶进行补钙是一种既科学又经济方便的方法。目前高钙奶中添加的钙剂主要为碳酸钙和乳钙等分子钙剂，容易出现沉淀、絮凝和乳析等问题，添加合适的乳化稳定剂有助于解决这些困扰乳制品生产商和消费者的问题。为此，我们分析了几种高钙奶稳定剂在高钙奶体系中的作用。高钙奶的制作参照谢继志等的方法进行，     

麻纤维热稳定性的研究

作者报道了用热重法和差示扫描量热法对六种麻纤维进行测试的结果,对麻纤维热稳定性的差异及其原因进行了分析。     

酶制剂热稳定性的研究进展

很多研究结果表明,在单胃动物日粮中添加以非淀粉多糖酶为主的复合酶制剂,可显著提高畜禽营养物质的消化率,从而提高单胃动物的日增重和饲料转化率。非淀粉多糖酶可以降解日粮中单胃动物本身不能消化的非淀粉多糖(木聚糖、β-葡聚糖、果胶等),同时释放被细胞壁包裹的营养物质,并可降低食糜粘度,促进营养物质在胃肠道的消化吸收。制粒可以破碎细胞壁,促进粗纤维、粗蛋白质等营养物质的消化吸收,提高饲料转化率。但是在制粒过程中,由于蒸汽的输入和压模机的摩擦,温度可达60~100℃;而温度的升高将导致酶的失活,并且随着温度的升高和时间延长,酶…     

中性高钙液体奶的钙剂筛选及稳定性研究

对中性高钙液体奶生产中不同钙剂和稳定剂对产品稳定性和品质的影响进行了研究。结果表明,以乳钙为钙强化剂,添加量为6g/L,微晶纤维素复配卡拉胶(1∶1)为稳定剂,添加量为3g/L,制备的中性高钙液体奶对热稳定,口感不会明显增稠,钙含量(以钙元素计)可达2.64g/L。     

高钙液态奶中试加工工艺的研究

对高钙液态奶中试加工工艺进行了研究。通过向原料奶中添加乳钙、奶油粉、酪蛋白磷酸肽、维生素D3等物质，在一定条件下生产高钙液态奶。通过中试试验确定了各种物质的添加量和生产工艺。生产的高钙牛奶具有比普通牛奶更好的口感和香味．没有一般高钙类产品常见的涩味，产品在保质期内稳定性好。     

Impact of source and level of calcium fortification on the heat stability of reconstituted skim milk powder

Calcium enrichment of food and dairy products has gained interest with the increased awareness about the importance of higher calcium intake. Calcium plays many important roles in the human body. Dairy products are an excellent source of dietary calcium, which can be further fortified with calcium salts to achieve higher calcium intake per serving. However, the addition of calcium salts can destabilize food systems unless conditions are carefully controlled. The effect of calcium fortification on the heat stability of reconstituted skim milk was evaluated, using reconstituted skim milks with 2 protein levels: 1.75 and 3.5% (wt/wt) prepared using low and high heat powders. Calcium carbonate, phosphate, lactate, and citrate were used for fortification at 0.15, 0.18, and 0.24% (wt/wt). Each sample was analyzed for solubility, heat stability, and pH. The addition of phosphate and lactate salts lowered the pH of milk, citrate did not have any major effect, and carbonate for the 1.75% protein samples increased the pH. In general, changes in solubility and heat stability were associated with changes in pH. Calcium addition decreased the solubility and heat stability. However, interestingly, the presence of carbonate salt greatly increased the heat stability for 1.75% protein samples. This is due to the neutralizing effect of calcium carbonate when it goes into solution. The results suggested that the heat stability of milk can be affected by the type of calcium salt used. This may be applied to the development of milk-based calcium enriched beverages.     

无机盐对牛乳蛋白质胶体稳定体系影响的研究

通过测定牛乳蛋白质变性温度研究钙盐、磷酸盐、柠檬酸盐在不同离子浓度下对牛乳热稳定性的影响,结果表明:在鲜牛乳、脱脂奶粉复原乳中随钙离子浓度增大,变性温度降低,即热稳定性降低;增加磷酸盐浓度并未提高牛乳的热稳定性,反而使牛乳的热稳定性降低;添加适量的柠檬酸盐可提高牛乳的热稳定性,超过一定量则使热稳定性降低。     

高钙酸性含乳饮料的研制

对高钙酸性含乳饮料的工艺及配方设计进行了研究。叙述了工艺设计，包括原料选择、主要设备、工艺流程、操作要点、工艺参数等。还根据各种原料的不同特点，确定使用何种原料及用量，最终得出最佳配方为：脱脂奶粉3.5％，白砂糖10％，稳定剂0．4％，乳酸0．3％，柠檬酸0．35％，柠檬酸钙0．1％，香料0．1％(均为质量分数)，其余为水。     

Effect of the modified high methoxyl pectin on the stability of the fermented milk beverage

Stability of milk drinks could be improved by adding high methoxyl pectin. In this work, effect of the modified high methoxyl pectin (MHMP) on the fermented milk beverage (FMB) was investigated by the characteristics of adsorption, viscosity, rheological properties, particle size, zeta-potential (ζ-potential), microstructure, and phase behavior. The low concentration of MHMP (<0.2%, w/v) and final pH (<4.0) might easily cause the instability among the particles inducing from the bridging flocculation. The FMB system obviously had a good stability as the adding of 0.4% MHMP. Meanwhile, the particle size had a slight downward trend with decreasing the value of pH. The increase of MHMP concentration could increase the properties of viscosity and ζ-potential. However, the ζ-potential of the system had a decreasing trend by reducing the pH of the FMB with the same concentration of MHMP. The microstructure of the FMB was thick and dense compared with the sample without MHMP. As the concentration of MHMP was above 0.4%, the FMB system presented the uniform dispersion and only slight stratification water occurred for the phase behavior. Besides, it was also indicated that most part of MHMP was not adsorbed onto the casein micelles but was involved in a network with MHMP/casein complexes in the FMB.     

Influence of variation in calcium content on casein micelle stability and techno-functional properties of buffalo milk

Changes in techno-functional properties of buffalo milk were evaluated due to variation in calcium content. Decalcification resulted in significant variation in ζ-potential, casein size, colour and η_app. However, calcium addition only influenced ζ-potential of milk. In case of acid gelation, the time and temperature required for coagulation decreased significantly for both calcium-depleted and -added milks. However, during chymosin gelation, only 20%–30% of calcium-depleted milk coagulated with an increased clotting time. Furthermore, calcium addition increased firmness, consistency and cohesiveness of both chymosin and acid-induced gelation.     

豆奶稳定性的探讨

主要研究了原材料,加工工艺,乳化剂及稳定剂对豆奶稳定性的影响。