Foods by the nature of the way they are grown or produced on farms in open environments often require cleaning before use. Cleaning ranges from simple removal of dirtfrom egg shells with an abrasive brush to the complex removal of bacteria from a liquid food by passing it through a microporous membrane. Grains must be cleaned of stones before use. Cleaning can be accomplished with brushes, high-velocity air, steam,water, vacuum, magnetic attraction of metal contaminants mechanical separation, and so on, depending on the product and the nature of the dirt.
The cleanliness of water used in the soft drink bottling industry must exceed many of the standards found adequate for drinking water. If a high degree of carbonation is to be achieved, then the water used in making the drink must be remarkably free of dust particles, colloidal particles, and certain inorganic salts, since these minimize carbon dioxide solubility and promote excessive escape of gas bubbles. To adequately water may require that city water receive such additional treatments as controlled chemical flocculation of suspended matter, sand filtration, carbon purification microfiltration, and deseration. This is no longer the unit operation of cleaning but a total cleaning process.
Some cleaning methods are dictated by surface characteristics of the product. Because pineapples have an irregular surface, the scrubbing action of high-pressure water jets is used.
Just as different food materials require special cleaning, the surfaces of food processing equipment need thorough and frequent attention. The cleaning of equipment, as well as a facility’s walls and floors must take into consideration the chemical and physical properties of both the surface to be cleaned and the type of soil. Many types of soil can be removed with mildly alkaline detergents, but strong alkali may be required for more tenacious deposits and heavy deposits of fats and oils or builtup protein deposits. Alkaline films and hard-water scales may require mildly acid detergents. Strong acids are highly corrosive to several metals, fabrics wood .rubber, and concrete floors. Strong alkalis also are corrosive to various metals and to glass. For these reason8,moderately alkaline and neutral detergents And wide application in the food industry. Several are listed in Fig. 5.2, along with the properties that affect their cleaning efficiency. Food plant operators generally call on detergent manufacturers for expertise in establishing highly effective cleaning procedures since these further depend on detergent concentrations, temperatures of application, order of application where more than one cleaning aid is used, and other variables.
- 匿名使用者2 0 年前最佳解答
- ?Lv 72 0 年前
From 0204: 等你呦~
- 匿名使用者2 0 年前
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