UHT Milk Processing Line
UHT Milk Processing Line Description
UHT milk is a dairy product with a long shelf life that can be directly consumed. This dairy product not only improves the color and taste, but also improves the original nutritional value. Sterilized milk, also known as long-lasting fresh milk, refers to products that are using fresh milk as raw material, then after purified, standardized, homogenized, UHT sterilized and aseptically packed into containers.
UHT milk does not need to be refrigerated and can be stored at room temperature. Depending on the packaging container, the shelf life generally ranges from 3 months to 12 months.
The entire UHT milk processing line keeps materials processed in a closed environment to ensure the commercial aseptic state of the final product.
The capacity of the production line can be designed from 1 ton/hour to 50 tons/hour according to the different requirements of customers.
200g—2500g aseptic cartons, aseptic pouches or PE bottles can be packed according to client’s different requirements.
The auxiliary equipment like CIP system, chill water generating system, boiler, RO soft water treatment system are needed for the whole production line.
The End Products Of UHT Milk Processing Line
UHT milk in bottles: The secondary sterilized milk usually will be filled into PE material bottles, and the shelf life is 6 months with normal temperature.
UHT milk in aseptic cartons: The most popular package for UHT milk is aseptic cartons, the aseptic cartons include diamond pack cartons, SIG Combibloc pack cartons, Tetra Pak aseptic brick cartons. These cartons are composed of 3-7 layers of paper, PE, and aluminum foil composite material, which has very good light resistance and airtightness and extend milk shelf life to 6-9 months stored with 20-25℃.
UHT milk in aseptic pouches: It mainly refers to Tetra pak aseptic pillow pouches and PrePack pouches. The shelf life of UHT milk in these aseptic pouches can also reach 45-60 days.
Technological Flowchart Of UHT Milk Processing Line
The raw milk undergoes acceptance, preliminary purification(if you want to make skimmed UHT milk, you can add one centrifuge separator to remove the fat in milk after purification),pre-pasteurization, and then cools to about 4℃, and stores it in a milk insulation tank. After standardization, homogenization, UHT sterilization and degassing, the end UHT milk will be filled into an aseptic carton or pouch packaging.
Classification Of UHT Milk Processing Line
According to the sterilization method
Secondary sterilization milk: the milk is pasteurized in advance, then filled into the container, and then sterilized by pressure in a retort sterilizer at 110-120°C for 10-20 minutes. This kind of sterilized milk is generally filled into plastic bottles or glass bottles. The product shelf life generally reaches 6 months.
Ultra-high temperature sterilized milk (UHT milk): raw cow (goat) milk is used as raw material, with or without reconstituted milk. In the state of continuous flow, it is generally sterilized at 120-150℃ holding for 0.5-4S. Through rising sterilizing temperature and shorten holding time can also achieve the same sterilization effect. This sterilization method is called ultra-high temperature sterilization. The UHT milk usually filled into aseptic cartons and pouches.
According to protein content:
Sterilized pure milk (P≥2.9%): raw cow and goat milk or reconstituted milk as raw materials, skimmed or non-skimmed, ultra-high temperature instantaneous sterilization, and aseptic filled into cartons or pouches.
Sterilized flavored milk: (P≥2.3%): The protein content needs to be greater than or equal to 2.3%, and ingredients like fruit juice can be added to such dairy products.
Key Machine Of UHT Milk Processing Line
Purification of raw milk
The purpose of raw milk purification is to remove mechanical impurities in the milk and reduce the number of microorganisms. Filter purification or centrifugal purification can be used. Simple primary filtration is performed by installing a filter screen on the milk receiving tank and spreading multiple layers of gauze. The filter cloth should be cleaned and sterilized frequently. The use of a centrifugal milk purifier can significantly improve the purification effect and help improve the quality of the product. The centrifugal milk purifier can also remove breast somatic cells and certain microorganisms in the milk. The milk purifier is placed after filtering and before cooling.
Raw milk pre-pasteurization machine
Generally, If the capacity of UHT milk processing line is big, then there is necessary to pre-pasteurize. The purpose of pre-pasteurization is as follows:
- Preliminarily kill most bacteria and pathogenic bacteria, make UHT sterilization more thorough, to ensure the safety of food and improve the storage of finished products.
- Inhibit the activity of enzymes, so as to avoid fat hydrolysis, enzymatic browning and other undesirable phenomena in the finished product. The sterilization temperature is 80℃ and the time is holding for 15min.
Milk cooling and storage equipment
The cooling temperature is 5°C to inhibit the growth of bacteria. The number of microorganisms in milk varies with the length of storage time and temperature. The plate heat exchanger is applied to cool down the milk.
In order to ensure the continuous production of the factory, there must be a certain amount of raw milk storage. Generally, more than two storage tanks are set up. The storage tanks are equipped with stirring to stir the raw milk regularly to prevent fat from rising and causing uneven distributi