Drink Asia July August 2019 | Page 32

Drink Wrap environment like probiotic milk, fermented juices etc. The aseptic packaging involves the below mentioned four basic elements: Product Sterilization: The product sterilization is done by elevating the temperature of the product for a specific period of time and maintaining this time-temperature combination for a given period in order to achieve the desired degree of sterility. Thereafter, the product is subsequently cooled usually to ambient temperature. Heating and cooling should be performed as rapidly as possible to achieve the best quality, depending upon the nature of the product. In this process, the faster heat exchange rate is beneficial in terms of cost. Other than heating, several other methods are getting attention nowadays such as: ultra-high pressure packaging; use of microwaves; electrical resistance heating; and high voltage discharge. Packaging and Equipment S t e r i l i z a t i o n : The second and equally critical element is killing all the microbes of packaging material. In case it is not done effectively then it may limit the effect of first element i.e. product sterilization. There are several agents that are very effective in sterilizing the packaging materials and equipment. They are mentioned below: • Heat: Elevating the temperature up to a certain level and for a given time may kill most of the microorganisms. Equipment like pipelines, tanks and fillers are sterilized by hot water (75-85 °C) or saturated steam under pressure. • Chemicals: Other than various acids e.g. per-acetic acids and alcohols, hydrogen peroxide provides a wide range of useful effects in sterilizing the equipment. • Radiations: Gamma-radiation has been used for years to sterilize packaging materials. This has been widely used in aseptic systems for packaging acid and acidified foods. The gamma-radiations use to have good penetrating powers and they get easily penetrated through bulk packages when used at commercial irradiators. Filling: Once the temperature of the product is elevated then it is passed through a holding tube. This holding tube provides the right time and temperature to the product for proper sterilization. A deaerator is used to The aseptic packaging of beverages allows the beverage manufacturers to meet consumer demands for better quality and safe products with simple ingredients Drink Asia 32 July-August 2019 remove the air from the beverage prior to packaging. This is done to avoid any unwanted oxidative reaction post packaging. After the deaeration process, the sterilized beverage is stored in aseptic surge tank. The product/beverage is further pumped into the surge tank and is removed by maintaining a positive pressure in the tank with sterile air or other sterile gas. Also, the positive pressure must be monitored and controlled within the tank to protect the tank from any contamination. Sealing: Post aseptic filling, closure and seal integrity is one of the most significant steps to protect beverages from any type of contamination. Longitudinal sealing and transversal sealing are usually done in aseptic sealing. The aseptic packaging of beverages allows the beverage manufacturers to meet consumer demands for better quality and safe products with simple ingredients. However, the higher costs for the equipment, materials and labour needed for the technical/ complex sterilization process have stymied aseptic packaging adoption in the beverage industry. But with so many benefits being served by this technology, the industry would not let the economic barrier stop it from being widely used!