File Name: milk processing and preservation .zip
- Optimum Thermal Processing for Extended Shelf-Life (ESL) Milk
- Ultra-high-temperature processing
- THE CHEMISTRY OF MILK
Optimum Thermal Processing for Extended Shelf-Life (ESL) Milk
The heat used during the UHT process can cause Maillard browning and change the taste and smell of dairy products. UHT milk packaged in a sterile container has a typical unrefrigerated shelf life of six to nine months. In contrast, flash pasteurized milk has a shelf life of about two weeks from processing, or about one week from being put on sale. The most commonly applied technique to provide a safe and shelf-stable milk is heat treatment. However, without commercially available aseptic packaging systems to pack and store the product, such technology was not very useful in itself, and further development was stalled until the s. In , APV pioneered a steam injection technology, involving direct injection of steam through a specially designed nozzle which raises the product temperature instantly, under brand name Uperiser; milk was packaged in sterile cans.
Extended shelf-life ESL or ultra-pasteurized milk is produced by thermal processing using conditions between those used for traditional high-temperature, short-time HTST pasteurization and those used for ultra-high-temperature UHT sterilization. It should have a refrigerated shelf-life of more than 30 days. To achieve this, the thermal processing has to be quite intense. The challenge is to produce a product that has high bacteriological quality and safety but also very good organoleptic characteristics. Hence the two major aims in producing ESL milk are to inactivate all vegetative bacteria and spores of psychrotrophic bacteria, and to cause minimal chemical change that can result in cooked flavor development. This can be best achieved by heating at high temperature for a short holding time using direct heating, and aseptically packaging the product.
By Niamh Burke, Krzysztof A. Ryan and Catherine C. Sampling and analysis occur along the milk processing train: from collection at farm level, to intake at the diary plant, the processing steps, and the end products. Milk has a short shelf life; however, products such as milk powders have allowed a global industry to be developed. Quality control tests are vital to support activities for hygiene and food standards to meet regulatory and customer demands.
PDF | Milk and milk products which provide nutrition have Erroneous process of pasteurization and adulteration in the milk that is pasteurized.
THE CHEMISTRY OF MILK
Robinson: Modern Dairy Technology pp Cite as. Milk is extremely perishable, yet for a number of reasons it is desirable to preserve it for later consumption. Today, drying is the most important method of preservation.
Journal of Milk and Food Technology 1 January ; 15 2 : 74— To determine the effectiveness of freezing as a preservative of chocolate drink, three commercial samples processed as follows were used: Sample 1. Held in vat 20 min. Sample 2—Skimmilk heated in vat and 95 lb of chocolate syrup and 54 lb of sugar added gal of skimmilk. Sample 3.
The principal constituents of milk are water, fat, proteins, lactose milk sugar and minerals salts. Milk also contains trace amounts of other substances such as pigments, enzymes, vitamins, phospholipids substances with fatlike properties , and gases.