Tiêu đề Industrial Processes - IBBI Exam-1-1.pdf ✅

Cleaner Production Assessment in Dairy Processing Page 8 2.1 Process overview 2.1.1 Milk production The processes taking place at a typical milk plant include: • receipt and filtration/clarification of the raw milk; • separation of all or part of the milk fat (for standardisation of market milk, production of cream and butter and other fat-based products, and production of milk pow ders); • pasteurisation; • homogenisation (if required); • deodorisation (if required); • further product-specific processing; • packaging and storage, including cold storage for perishable products; • distribution of final products. Figure 2–1 is a flow diagram outlining the basic steps in the production of w hole milk, semi-skimmed milk and skimmed milk, cream, butter and buttermilk. In such plants, yogurts and other cultured products may also be produced from w hole milk and skimmed milk. 2.1.2 Butter production The butter-making process, w hether by batch or continuous methods, consists of the follow ing steps: • preparation of the cream; • destabilisation and breakdow n of the fat and w ater emulsion; • aggregation and concentration of the fat particles; • formation of a stable emulsion; • packaging and storage; • distribution. Figure 2–2 is a flow diagram outlining the basic processing system for a butter-making plant. The initial steps, (filtration/clarification, separation and pasteurisation of the milk) are the same as described in the previous section. Milk destined for butter making must not be homogenised, because the cream must remain in a separate phase. After separation, cream to be used for butter making is heat treated and cooled under conditions that facilitate good w hipping and churning. It may then be ripened w ith a culture that increases the content of diacetyl, the compound responsible for the flavour of butter. Alternatively, culture inoculation may take place during churning. Butter w hich is flavour enhanced using this process is termed lactic, ripened or cultured butter. This process is very common in continental European countries. Although the product is claimed to have a superior flavour, the storage life is limited. Butter made w ithout the addition of a culture is called sw eet cream butter. Most butter made in the English-speaking w orld is of this nature.