HACCP在搅拌型酸牛奶生产中的应用

人类赖以生存的能源——食品，随着食品生产工业化比重的增加，食品的不安全因素越来越多。特别是近几年来，国内的液态乳制品风波、婴儿奶粉事件，一次次惊起了广大消费者对食品工作特别是乳制品的关注，为了食品安全人们发明了许多方法和手段，其中危害分析与关键控制点(Hazard Analysis and Critical Control Point，简称HACCP)是行之有效的方法之一，正在世界范围推广应用。

运动型牛奶产品应用前景研究

牛奶作为一种新型的运动饮料,与商业的运动饮料相比,在力量训练和耐力训练恢复中的作用引起了人们的兴趣和关注。通过查阅大量国内外研究文献,从牛奶的成分与人体运动能力的关系、牛奶与运动饮料对比和运动型牛奶产品开发及应用等方面进行综合分析,牛奶作为一种新型的运动饮料将具有广阔的市场前景。

搅拌型酸牛奶最佳冷却温度的选择

本文在多次的生产试验中,通过采用不同的冷却温度对发酵后的搅拌型酸牛奶进行冷却,再测出相应成品的粘度和乳清水分离的时间,从而得到温度与粘度之间的对应关系,在这些对应关系中,找出最高粘度及与之对应的温度,在这一温度条件下,产品不需加入任何添加剂或增加其它原材料而能得到令人满志的效果。

搅拌型酸牛奶常见质量问题及控制

阐述了搅拌型酸牛奶常见的质量问题,分析了产生的原因。针对具体问题提出相应的解决办法。包括:搅拌型酸牛奶原料的质量状况、加工设备技术水平、生产环境、加工工艺、包装材料、贮运、销售过程中易出现的胀包;发霉;乳清析出;组织状态不细腻;酸度过高;口感刺激、不柔和;甜度过高、口感不好;香气不足;有异味(奶粉味、苦味等);酸奶中有小颗粒;口感偏稀等质量问题。

搅拌型酸牛奶增稠剂对比试验

在制作搅拌型酸牛奶生产中，往往由于牛奶中总固形物稍低．达不到规定标准而造成不凝乳或凝乳甚差，致使粘硬度不足而告失败。本试验研究选择PGA、CMC、明胶、粒粒橙悬浮剂及新鲜玉米、马铃薯淀粉时行了若干次对比试验。结果证明，可视为一种物美价兼的优质纯天然增稠剂。

符合绿色食品标准的搅拌型酸牛奶生产技术

喜欢喝搅拌型酸牛奶的人越来越多，为保证人们的健康饮用，生产符合绿色食品标准的搅拌型酸牛奶有着重要意义。本文主要通过研究符合绿色食品标准的搅拌型酸牛奶的成品的标准及生产技术，确定了搅拌型酸奶从原料的制备到生产工艺的操作标准。

几种不同稳定剂对凝固型酸奶品质的影响

凝固酸牛奶有组织状态 ,凝固怎样是反映质量的关键指标。在酸奶发酵工艺中 ,分别采用1%、1 5%、2 %不同比例的明胶、TM 2 0、玉米淀粉三种不同稳定剂发酵对照试验与普通凝固型酸奶在组织状态、口感风味、发酵酸度、生产成本上进行数次比较。结果表明 ,若要保证凝固型酸牛奶最佳适口性和最佳组织状态 ,选用酸牛奶中添加 1 5%TM 2 0或 0 5%明胶 ,最后选 1%明胶 ;若要保证凝固型酸奶的适口性、组织状态 ,又要考虑成本不太高 ,可依次选择在普通酸牛奶中添加 1%玉米淀粉、0 5%明胶、1 5%TM 2 0。

凝固型酸牛乳的研制

主要介绍了采用天然原料接种双歧杆菌 ,保加利亚杆菌 ,嗜热链球菌发酵而成的一种具有很高的营养价值 ,又有保健作用的天然营养型饮料 ;详细介绍了该饮料的生产工艺 。

The Effect of Culture Condition on Type 5 Capsular Polysaccharide Production of Staphylococcus aureus from Diary Cattle

[Objective] The effect of different culture conditions on type 5 capsular polysaccharide production of Staphylococcus aureus from diary cattle was studied to provide simple way for CP production and preparation and laid foundation for carrying out new polysaccharide vaccine research. [Method] Staph-ylococcus aureus was isolated from milk sample of sick dairy cattle and capsular polysaccharide serotypes were identified. Type 5 capsular polysaccharide was cultured on BHI,solid columbia and mod110 culture media. Glucose and lactose were taken as carbon sources for every culture media in solid and liquid state. Therefore 9 different culture conditions were taken to study the effect of culture conditions on capsular polysaccharide production. [Result] Different culture conditions indicated that compared with columbia culture media, BHI culture media could decline capsular polysaccharide production and mod110 culture media could increase capsular polysaccharide production. While for same culture media, solid culture media was better for capsular polysaccharide production,meanwhile,taken lactose as carbon source could increase capsular polysaccharide production.

Precise Calculation System of Total Mix Ration for Lactating Cow

[Objective] The paper was to precisely predict nutrient requirements and optimize ration formula, and explore the inherent feature of ration optimization of dairy cow. [Method] Based on cornell net carbohydrate and protein system （CNCPS） with integrating dynamic prediction models on main nutrient requirements of dairy cattle recommended by NRC （2001） and the CNCPS parameter database accumu- lated by Chinese feed database, the ration nutrient requirement dynamic calculation and total mixed ration （TMR） formula optimizing system for Holstein dairy cow was developed using FOXPRO database system and parametric linear programming algo- rithm. [Result] By optimizing a specific cow ration and analyzing its completed nutri- ents, the results showed that this system could entirely consider a lots of nutrient balances, such as concentrate fraction and forage fraction balance, rumen degrad- able protein and rumen undergradable protein balance, crude protein and lactation net energy balance, fibrous substances （ADF, NDF） and non-fiber carbohydrates （NFC） balance, calcium and phosphate balance, electrolytes balance and trace ele- ment balance etc., and could also calculate intestinal amino acid flow in terms of different models. [Conclusion] By using dynamic mathematical equations and comput- erized program, it can be realized for the ration formula design of lactating cow with all-round interoperable but mutual-constraining each other among ration nutrients.

Prevalence of lactase persistent/non-persistent genotypes and milk consumption in a young population in north-west Russia

AIM： TO estimate the prevalence of the lactase non-persistent genotype （C/C-23910） in a northern Russian population in accordance with ethnicity, and to evaluate self-reported milk consumption depending on lactase activity. METHODS： Blood samples for genotyping lactase activity, defining the C/T-13910 variant by polymerase chain reaction, and direct sequencing were taken from 231 medical students of Russian origin aged 17-26 years. We analyzed milk product consumption by questionnaire which was specially designed for the estimation of milk consumption and abdominal complaints. RESULTS： We found that the prevalence of the C/C-13190 genotype in the northern Russian population was 35.6%. The other genotypes nearby C/T-13910 and associated with lactase activity were not present in the study population. The consumption of milk among people with the non-persistent genotype tended to be lower than among the lactose tolerant subjects, but was not statistically significant. CONCLUSION： An investigation of the lactase persistent genotype in a northern Russian population has not been performed before, The genotype did not affect the consumption of milk products in this population which could be explained by low consumption of milk products among the entire study population.

An Investigation on Thermization of Milk in Can Using Computational Fluid Dynamics

Thermal processing of milk is an important unit operation to inactivate the spoilage organism and enzymes and thus increase the storage life of milk, It was very difficult to find out the temperature distribution inside the cans during thermal processing. A Computational Fluid Dynamics （CFD） model was developed for thermization of milk in the can heating at 65℃ for the first time to determine the temperature distribution in the canned milk at stationary position. This developed CFD model was validated with the experimental measurements of temperature. The effects of thermization temperature on milk flow profile （velocity）, milk temperature and viscosity profiles inside the can during thermal process were investigated. Temperature profiles of milk in can at three different planes （i.e. top, middle and bottom plane） were studied. Moreover, thermization unit was calculated by correlating with temperature and it was found that maximum thermization unit was achieved at 540 s of thermal processing of milk in can.

Comparison the Genetic Potential of Some Growth ＆ Milk Trait, s of Hybrid （Crossed） Saanen with Native Goat （Lori Black Goat） versus Native Goats in Qom Province

The performance of some growth and milk traits of selected Qomi native （Lori black） goats and hybrids of saanen with native goats during 2008-2010 was compared. Growth traits include birth weight （BW）, one-month weight （1 MW）, weaning weight （WW） and 6-month weight （6 MW）. Also the milk production traits was monthly milk production on 2, 3, 4, 5th months （quantitative traits） and some milk composition included dry matter （%DM）, fat （%F）, and protein （%P） percentage on during of production （qualitative traits）. There were no significant differences in sex, birth type and genetic group for BW. Also the effect of genetic groups on 1 MW, WW, and 6 MW was significant, while effects of sex and birth type on 1 MW, WW and 6 MW was not significant. Also MW （Mothe＇s weight） had no significant effect on BW, 1 MW, WW and 6 MW. The average of daily milk records was 0.48 kg for nativel and 1.1 kg for crossed goats. The maximum monthly milk records in two groups were in second month （native： 0.64 -4- 0.05, crossed： 1.44 ~： 0.12） and the minimum were in fifth month （native： 0.36 ＋ 0.03, crossed： 0.77 -4- 0.05）. %DM, %F and %P in 5th month were higher than other months in two groups. Effects of genetic groups on milk production and also on average of%F, %DM and %P were significant. This study showed that the crossbreeding has a significant effect on most milk production and growth traits in Iranian native goats.

Heat Transfer Analysis of Sterilization of Canned Milk Using Computational Fluid Dynamics Simulations

A uniform and effective heat distribution inside the canned milk is very crucial for achieving effective sterilization. It is extremely difficult to establish the temperature profile inside the canned milk during continuous industrial scale operation. Computational fluid dynamics （CFD） simulation can be a useful tool to determine the temperature distribution of the fluid inside the can during the sterilization process. A CFD model was developed for the sterilization of canned milk at 121 ~C. The simulation results were validated with the experimental measurements of temperatures. The formation and movement of slowest heating zone （SHZ） during the sterilization process was tracked. Moreover, effect of can position （vertical and horizontal） during processing on milk temperature distribution inside the can was also investigated. Higher Grashof and Rayleigh numbers were obtained for vertical positioning of can compared to horizontal can processing. Further, effectiveness of the process was calculated based on F-value and these results reinforced the positive effect of horizontal position of can during the sterilization process.

Implementation of Cooling Systems to Enhance Dairy Cows＇ Microenvironment

A tool was developed to assist the cooling systems designer in designing and installing the microsprinklers and fan cooling system. The tool was developed by integrating a mathematical model into an electronic spark map in order to use the mathematical model practically. The mathematical model was developed using the designs, parameters, variables, and constant values of the microsprinklers and fans cooling system. Subsequently, an electronic spark map （decision tree） was developed, and then the mathematical model was integrated into the electronic spark map. Afterwards, C# （C Sharp） programming language was used to develop a computer system via the electronic spark map, and to make the user interface. The developed computer system assists the designer in making decisions to specify and to calculate the required discharge of cooling system pump, length and diameter of cooling system pipelines, number of cooling fans, and number of microsprinklers. Moreover, this tool calculates the capital investment and the fixed, variable, and total costs of the cooling system. However, the mathematical model of the spark map requires some input data such as： pressure and discharge of microsprinklers, and some other engineering parameters. Data of 4 cooling systems were used to carry out the model validation. The differences between actual and calculated values were determined, and the standard deviations were calculated. The coefficients of variation were between 2.25% and 4.13%.