乳及乳制品的品质检验

为了了解洛阳市乳制品的卫生和质量情况,笔者对洛阳市市售的乳及乳制品进行抽样检测,主要检测乳制品中蛋白质、脂肪的含量和微生物的指标是否符合国家标准。抽检乳及乳制品45种商标标示中的92个品种,共计144份样品,其中51份合格,93份不合格。鲜乳、酸乳25个品种,36份样品,24份合格,12份不合格;乳类饮品39个品种,55份样品,19份合格,36份不合格;乳粉类28个品种,53份样品,8份合格,45份不合格。其中不合格的原因主要是蛋白质和脂肪含量达不到国家标准,有的乳粉中蛋白质含量低于国家标准23.57倍(国家标准是不小于16.5%,实际含量仅为0.7%),有个别…     

热加工对牛乳品质的影响

牛乳是一种热敏性物质，研究热加工对乳及其乳制品质量的影响，对稳定提高乳及乳制品质量具有非常重大的意义。在任何一种乳制品的加工生产中，有时会不只一次地重复热加工工艺。如果掌握不好热加工工艺。即会对乳及乳制品质量带来许多不良影响二。如加热臭的产生、蛋白质的变性、乳石的生成、酶类的钝化、色泽的褐变及维生素的大量破坏等。１ 奶膜的形成奶膜即人们在加热牛奶时，在奶液表面形成的一层薄膜，也称奶皮：此膜随着加热时间的延长，其厚度逐渐增加。据研究认为，该膜的形成是由于乳液与空气接触界面层的蛋白质，在水份不断蒸发…     

感官检验法鉴别市售纯牛乳制品热处理方式的探讨

食品感官检验是在食品理化分析的基础上,集心理学、生理学、统计学的知识发展起来的一门学科.在食品行业中,除了理化指标以外,感官性质是决定产品质量的一个重要因素.通过感官检验的方法,对不同热处理工艺生产的纯牛乳制品加以区分,根据实验工作的目的和要求,选择三点检验法和分类检验法相结合进行实验操作.结果表明,感官检验法可以用于区分不同热处理的纯牛乳制品,作为鉴别纯牛乳热处理方式的检测方法,感官检验法具有一定的参考价值.     

兰州市不同来源鲜蛋品质分析与研究

本文对当前兰州市场5种不同品牌的鲜蛋进行抽样调查,通过实验室测定及统计分析来评定鲜蛋品质。结果表明:不同来源的鲜蛋品质存在差异;不同的储存时间对各品牌鲜蛋品质有不同的影响。综合考虑,正大蛋和土鸡蛋品质突出。     

体细胞数过高对乳制品品质的影响

本文主要阐述了体细胞数过高对乳制品营养价值、风味、加工特性以及贮藏特性等方面的不利影响。体细胞数过高,则乳脂率和酪蛋白含量降低;牛乳中盐类比例失调,牛乳热稳定性降低,凝固型酸奶的凝乳松散易碎裂,乳清易析出;过氧化物酶含量升高,乳品风味欠佳;脂肪氧化酶增加,其氧化产物游离脂肪酸含量上升,乳易酸败,缩短乳品保质期;蛋白水解酶尤其是血纤维蛋白溶酶含量和活性增加,造成乳蛋白大量水解,降低干酪产量;牛乳中有害微生物含量增加,抗生素残留的风险增加,降低乳制品食用安全。     

乳制品质量的影响因素及检测方法

本文阐述了原料奶理化指标、微生物指标及抗生素对乳制品质量的影响,并提供了检测方法,为确保乳制品质量安全提供了保障。     

乳制品检验液相色谱分析方法的建立与优化

高效液相色谱（HPLC）由于其具有检测精度高、重复性好、可同时分离几种甚至十几种物质的优势,被广泛应用在食品添加剂、兽药农残、活性营养成分等检测领域,而反相色谱因其具有可调节参数多、流动相配制灵活、适用性广的优势成为液相色谱分析的最常见方法。在实际检验工作中,针对不同的目标物质建立适宜的分析方法,配备合适的色谱条件是必不可少的。本文以反相色谱方法的建立为例,详细论述了应如何针对某种成分建立液相色谱分析方法并通过调整流动相种类、色谱柱参数等条件进行方法的优化,对于实际乳制品检验工作中方法的优化和建立有一定的参考价值。     

乳及乳制品中舒巴坦敏感β-内酰胺酶类药物检验方法及探讨

由于目前乳品行业出现个别掺杂使假现象,生鲜牛乳中加β-内酰胺酶类药物来分解牛乳中残留青霉素,使有抗奶无法正常检出。为了测出此种不合格牛乳,有关检测部门新开展了此类检测项目,基本上采用β-内酰胺酶的试剂盒检测法与舒巴坦敏感β-内酰胺酶类药物检验方法来确认。本文主要研究乳及乳制品中舒巴坦敏感β-内酰胺酶类药物的检验方法,探讨检测过程中的具体步骤,以及时、准确地确认乳及乳制品中是否含有β-内酰胺酶类药物,达到最佳检测效果。     

2008年全球奶制品市场展望

美国的奶牛业继续因牛奶供应变化导致的涨跌而呈现周期性波动,并且正在影响全球市场。2008年,3个因素综合结果创新了牛奶价格。     

Quality defects in market beef and dairy cows and bulls sold through livestock auction markets in the Western United States: II. Relative effects on selling price

Relative effects of Beef Quality Assurance (BQA)-related defects in market beef and dairy cows and bulls on selling price at auction was evaluated during 2008. The presence and severity of 23 BQA-related traits were determined during sales in Idaho, California, and Utah. Overall, 18,949 unique lots consisting of 23,479 animals were assessed during 125 dairy sales and 79 beef sales. Mean sale price ± SD (per 45.5 kg) for market beef cows, beef bulls, dairy cows, and dairy bulls was $45.15 ± 9.42, $56.30 ± 9.21, $42.23 ± 12.26, and $55.10 ± 9.07, respectively. When combined, all recorded traits explained 36% of the variation in selling price in beef cows, 35% in beef bulls, 61% in dairy cows, and 56% in dairy bulls. Premiums and discounts were determined in comparison with a "par" or "base" animal. Compared with a base BCS 5 beef cow (on a 9-point beef scale), BCS 1 to 4 cows were discounted (P < 0.0001), whereas premiums (P < 0.05) were estimated for BCS 6 to 8. Compared with a base BCS 3.0 dairy cow (on a 5-point dairy scale), more body condition resulted in a premium (P ≤ 0.001), whereas a less-than-desirable BCS of 2.0 or 2.5 was discounted (P < 0.0001). Emaciated or near-emaciated cows (beef BCS 1 or 2; dairy BCS 1.0 or 1.5) were discounted (P < 0.0001). Compared with base cows weighing 545 to 635 kg, lighter BW beef cows were discounted (P < 0.0001), whereas heavier beef cows received (P < 0.05) a premium. Compared with a base dairy cow weighing 636 to 727 kg, lighter BW cows were discounted (P < 0.0001), whereas heavier cows (727 to 909 kg) received a premium (P < 0.01). Beef and dairy cows with any evidence of lameness were discounted (P < 0.0001). Presence of ocular neoplasia in the precancerous stage discounted (P = 0.05) beef cows and discounted (P < 0.01) dairy cows, whereas at the cancerous stage, it discounted (P < 0.0001) all cows. Hide color influenced (P < 0.0001) selling price in beef cattle but had no effect (P = 0.17) in dairy cows. Animals that were visibly sick were discounted (P < 0.0001). Results suggest that improving BCS and BW, which producers can do at the farm or ranch level, positively affects sale price. Furthermore, animals that are visibly sick or have a defect associated with a possible antibiotic risk will be discounted. Ultimately, animals with minor quality defects should be sold in a timely manner before the defect advances and the discount increases.     

9月全国畜产品和饲料价格走势及分析

据对全国470个集贸市场畜禽产品和饲料价格定点监测,与8月相比,9月,生猪类产品、鸡蛋价格继续较大幅度上涨,牛羊肉价格略有上涨,玉米价格稳中有涨。本月猪粮比价为6．4：1,比8月上升0．1个百分点,连续两个月高于6．0：1的盈亏平衡点。     

1O月全国畜产品和饲料价格走势及分析

据对全国470个集贸市场畜禽产品和饲料价格定点监测,与9月相比,10月,生猪产品、家禽产品、玉米价格均回落;牛羊肉、生鲜乳价格小幅上涨。本月猪粮比价为6．3：1,比上月下降0．1个百分点。     

水产品消费市场分析--与网友共诊水产品市场

黄花鱼(网友):水产品真的存在卖难的问题吗?水产品卖难是流通方面的问题吗?我以为,在我国北方的消费者中,没有消费水产品的习惯。吴湘生:水产品市场确实存在卖难问题,也存在买难问题,从卖到买之间出现的问题,就是流通问题。水产品卖难的问题主要反映出,在现时环境下,水产品属于供大于求的产品。其次,水产品的加工仍属于整个产业链中最薄弱的环节。在水产加工食品中,除去冷冻鱼以外,至今没有走出一条更加广阔的路子。第3,大城市在规划中,出于卫生方面的考虑,往往把农贸市场,这一大众消费群体非常依赖的市场,设在远离城区的地方。而城区内非常…     

A case-control study of Washington dairy herds experiencing drug residue violations in market calves

The purpose of this case-control study was to examine the association between management practices and the occurrence of violative drug residues in calves originating from Washington dairies. In 1992, 74 dairies were identified as first-time offenders sending to abattoirs calves less than 1 week of age that had violative residue levels. Of these, 56 answered a subset of previously validated management questions from the 1991–1992 US National Animal Health Monitoring System National Dairy Heifer Evaluation Program (NDHEP) study during a violation investigation and comprised the case group. The controls were the 51 randomly selected Washington dairies that participated in the NDHEP, completed the four NDHEP questionnaires, and had not been identified as having residue violations. Management factors investigated were those associated with maternity and pre-weaning hygiene, vaccination and preventive practices, type and management of liquid calf feed, and general management. Other factors included herd somatic cell count (SCC), the presence of clinical signs associated with diseases of body systems, and herd size. Significant associations were detected between violation occurrence and the management of calving cows, colostrum volume and management, and the person responsible for calf care. Significant associations but of the wrong direction were found between violation occurrence and type and management of liquid calf feed. No significant associations were detected between violation occurrence and the remaining management factors, herd size, animals entering the herd, or SCC.     

A study of the factors that influence consumer attitudes toward beef products using the conjoint market analysis tool

This study utilizes an analysis technique commonly used in marketing, the conjoint analysis method, to examine the relative utilities of a set of beef steak characteristics considered by a national sample of 1,432 US consumers, as well as additional localized samples representing undergraduate students at a business college and in an animal science department. The analyses indicate that among all respondents, region of origin is by far the most important characteristic; this is followed by animal breed, traceability, animal feed, and beef quality. Alternatively, the cost of cut, farm ownership, the use (or nonuse) of growth promoters, and whether the product is guaranteed tender were the least important factors. Results for animal science undergraduates are similar to the aggregate results, except that these students emphasized beef quality at the expense of traceability and the nonuse of growth promoters. Business students also emphasized region of origin but then emphasized traceability and cost. The ideal steak for the national sample is from a locally produced, choice Angus fed a mixture of grain and grass that is traceable to the farm of origin. If the product was not produced locally, respondents indicated that their preferred production states are, in order from most to least preferred, Iowa, Texas, Nebraska, and Kansas.     

2008年水产品市场分析与2009年市场趋势

1、2008年,是中国水产品市场10年来发展最快、最好、表现最出色的时期 2008年1-11月．水产品价格指数114．1％,比2007年104．5％提高9．6点,增幅213．3％;比1997年100．2％提高13．9点。增幅690．5％。     

印度的奶业合作社与乳品市场

奶业是印度农业最重要的支柱.奶业的发展不仅为印度的很多农户提供了必需的营养,更在解决就业和农民增收等方面起着重要的作用.在许多地区,即便是没有土地的农民或是贫困的农民也都饲养奶牛.现代科技的应用以及在牛奶加工和销售过程中运用先进的管理系统,使印度的奶业发生了翻天覆地的变化.在印度,有大约7000万农户饲养着9800万头奶牛,平均每户奶农有1.2头奶牛.印度农户平均收入的22.5%来自于出售牛奶所得.     

浅析绿色畜禽产品的市场开发

“忽如一夜春风来”,随着国际上环境意识的增强,人们的消费心理、消费需求发生了显著变化,对绿色畜禽产品的需求和期望日益增长,崇尚自然、追求健康已成为优化市场结构的重要内容和趋势。绿色畜禽产品必将成为国际大市场中攻守皆宜的利器。在当今的国内外市场上,那些