Vacuum evaporation is a technique that is frequently used by manufacturers to preserve food and beverage products. When food or drinks are vacuum evaporated, they can usually be kept for longer periods of time without going bad. Vacuum evaporation may also be used to concentrate these products. For example, evaporated milk is essentially fresh milk that has been vacuum evaporated, resulting in a richer, creamier product that has a longer shelf life than fresh milk. In other words, evaporated milk is a concentrated dairy product.
Vacuumed food products can have several advantages over their fresh food counterparts. The most obvious benefit is product preservation. Consider, for instance, canned fruits and vegetables that undergo vacuum evaporation. These canned goods last a much longer period of time than fresh produce items, which can spoil within days of being purchased from a grocery store.
In general, vacuumed food products also have a lower weight and volume. This means they usually require less packaging. In addition, their smaller size can make them less expensive for companies to transport and store. For example, a can of frozen orange juice concentrate not only has a longer shelf life, but it also requires less packaging and less storage space than a fresh bottle of orange juice.
A vacuum evaporation system can be used to preserve or condense food and beverage products. Vacuum evaporators are devices in which liquids are evaporated from a low density substance in order to make a high density, more concentrated product. Many food and diary products require high vacuum evaporation techniques in order to achieve a usable, long lasting end product.
A vacuum evaporator usually contains three key elements. The first element is a heat exchanger that transmits heat from steam to the food product. The second element is a vapor-liquid separator, and the last element is a vacuum producer. This is typically operated by a steam ejector or a mechanical pump.
The type of vacuum evaporator used for a particular type of food or beverage product will vary depending on the product’s liquid characteristics. Factors to be weighed may include concentrate properties, foaming, temperature and timing impacts, and quality and flavor recovery. Cost is also often a factor for manufacturers.
Vacuum evaporation also occurs outside the food industry. In this context, it is often more specifically referred to as vacuum thermal evaporation and is used in the semiconductor, microelectronics, and optical industries. In general terms, vacuum thermal evaporation is a method of depositing thin films onto cool surfaces.