Dairy enzymology

The properties and the significance of the principal indigenous enzymes in milk, milk coagulants, enzymes from dairy microorganisms participating in cheese ripening, and spoilage enzymes are discussed. In particular, the properties of plasmin, lipases, phosphatases, enzymes from somatic cells, enzymes involved in antimicrobial and antiviral systems in milk, enzymes from lactic acid bacteria, propionibacteria, and microorganisms involved in smear- and mould-ripened cheese are reviewed. Some assay methods and the impact of some processing factors on selected enzymes are also discussed.     

乳品化学

利乐公司于2002年公司成立50周年之际推出新版的《乳品加工手册》。该公司积几十年乳品加工经验出版的这一手册,内容涵盖了乳品及相关产品的生产和加工的全过程管理。我们完全可以把它看作是一本教科书,对指导和推动乳品企业的生产及管理起到积极地促进作用。 本刊自2002年第10期起陆续摘登其中的重点内容进行连载,在此,我们也感谢利乐中国有限公司对中国乳品事业的大力支持。     

Dairy spreads

The market for yellow fats in Europe is surveyed with special reference to the UK and Sweden. Technical aspects of the production of spreads are discussed in relation to improving the spreadability of butter and producing blended and low fat spreads.     

乳糖酶在乳品中的应用

<正> 乳糖是牛乳中一种特有的双糖,由葡萄糖和半乳糖构成。乳糖的水解要通过乳糖酶水解乳糖的β半乳糖苷键,将乳糖转变成葡萄糖和半乳糖。 人体自身乳糖酶的缺乏并导致乳糖不耐受是一个世界性的问题,而在中国更是十分普遍的现象。它表现在不少人喝牛奶会有腹涨、消化不良或腹泻等不良反应。     

发酵乳制品

介绍了发酵乳制品的健康促进特性,生产中采用的菌种以及目前产品的种类,并且对发酵乳制品进行了展望。     

Ranking Dairy Sires by a Linear Programming Dairy Farm Model

Dairy sires were ranked for overall merit by an average daughter's contribution to farm net profit. Biological characteristics of sires and economic factors of a dairy farm were linked by linear programming. Availability and constraints of resources were in the model. Average daughter's returns over variable costs attributable to sire proofs for several traits was the measure of sire's net merit. The index of total economic merit for sires was the amount of change of net profit by milking progeny of different sires. Ranking considered sire's contribution to milk yield and feed intake of daughters caused by variations of proofs for milk, fat percent, and size, sire's nonreturn rate, veal calf sales of the offspring, and labor costs of slow versus fast milking daughters. Size of quota for daily milk shipments, cow housing capacity, labor for milking, and milk tank capacity were critical in determining ranking and forced greater emphasis on traits other than milk yield. Correlations between sire ranking on returns over variable costs and sire proofs were highest for milk and significant for fat percent, milking speed, size, and nonreturn rate. These traits had high standard partial correlations with and explained most of the variation of the index of total economic merit. This method aims at maximizing farm profits and may be applied to rank dairy sires on a national basis or to select sires for specific dairy farm operations. Production dollar index ratings on the same sires were closely correlated (?.87 to ?.96) with profit index ranking but are potentially misleading if constraints exist that limit maximum milk output per farm.     

USA Dairy Industry and Producer Views the International Dairy Federation

Although not to be construed as an official position of the United States dairy industry, observations (pro and con) on how the United States views the International Dairy Federation were presented. A proposal suggested by industry members, and holding the support of the International Dairy Federation, was outlined. The proposal embraces the formation of an Interim National Committee of the International Dairy Federation in the United States of America.