The process of hot filling is popular in the food and beverage industry because heat provides an effective method to sterilize the container and prevent bacterial growth. However, a hot fill bottle is not appropriate for low acidity foods because high pH levels indicate that spores may remain that have the potential of bacterial growth. As such, food and beverages with less than 4.5 pH are the best for the hot fill process.
Hot fill is a fairly simple procedure. First, the food or liquid is pasteurized to create a neutral microbiological environment. The containers are hot filled after pasteurization and capped, then turned on the side. This allows the hot liquid to enter and sterilize the cap as well as the interior of the container.
Once the hot fill is complete, the containers are cooled using water in the form of a shower, typically in a cooling tunnel, as continued exposure to heat could affect the product integrity and break down nutrients, vitamins and other elements.
After hot fill, most beverages and food have a shelf life of up to 6 to 12 months, although the precise shelf life is affected by variables such as the shape, size and type of container, storage conditions and the oxygen barrier level of the contents.
Typically, types of beverages are:
- Distilled (liquor)
- Hard soda
- Hot drinks
- Mixed drinks
- Fruit Juices
- Vegetable Juices
- Soft Drinks
- Dairy drinks