The main filling progress of RTD beverage products has hot filling & aseptic filling.
Hot filing process: the product is heated to a temperature over 70 degrees (normally 88 to 90 degrees) to remove harmful bacteria or microorganisms. Hot filling is suitable for high acid or lowers sensitive products (pH level more than 4.6) such as juice, sports drink, and energy drink.
Aseptic filling process: In the aseptic process, the aseptic filler is designed to sterilize the packaging material, and fill the sterile product into the package in a sterile environment. Aseptic filling is suitable for lower acid or sensitive products, which every type of beverage can be produced in an aseptic filling line.
Even an aseptic filling line is more efficient than hot filling, but not every manufacturer will use aseptic lines due to higher investment.
In another word, the aseptic line is suitable for higher quantities & fewer SKU.