Reliable Glass Bottles, Jars, Containers Manufacturer | Roetell

Hot Filling VS Cold Filling: What’re their Processes and Differences?

Do you have a brand you’re thinking about co-packing? Whether to employ the hot fill or cold fill approach is one of the options you will have chosen. However, you’ll need to know how each of these co-packing procedures works until you can make that choice. This article will give you a detailed analysis of the difference between a hot fill, and a cold fill, their benefits, and eventually, you’ll be able to make an informed decision. Read on!

What is Hot Filling

Hot filling is the technique of sterilizing a product, as well as the inside of a container or receptacle, as well as the cap or sealer, to assure product safety and extend shelf life. Without hot filling, dangerous germs in the bottle or liquid might infect or contaminate the food, making it unfit to eat or causing it to spoil sooner than expected. This procedure will extend the shelf life of the product, resulting in fewer wasted items. Glass or some types of strong polymers that can survive the extreme temps required to sterilize the container can be used for hot filling. It is commonly used for bottles carrying products with a pH of 4.5 or below, such as: ● Juices ● Flavoured liquids ● Isotonic beverages ● Drinks made from vegetables ● Marinades

How does Hot Filling Work?

Glass or various polymers can be used for hot filling. To eliminate any hazardous germs or microbes that may be present in a beverage, it is heated to 194 degrees Fahrenheit. The hot fluid is then poured into the bottle, which is then sealed and flipped on its side or upside down to guarantee that the cap is also sterilized.

The bottle and product are then quickly chilled. This procedure must be carried out with caution, as even a little dip in temperature before the appropriate time might result in incorrect sterilization and a dangerous product.

Type of Bottles Used

It’s vital to keep in mind that not all bottles can be hot-filled. The majority of popular plastic resins cannot survive hot filling temperatures. There are, however, common methods that make a certain type of PET plastic suitable with hot filling. They’re frequently referred to as “heat-set PETs.”

Heat-set In many hot fill beverage applications, PET is currently a typical plastic container material. They’ve been designed to resist hot-fill temperatures of up to 90 degrees Celsius while preserving clarity and lightness. PET is also recyclable, giving it a viable alternative to glass, which is not suitable with hot filling. 

PET bottles can endure the heat of hot filling without crumbling or becoming distorted, whereas glass bottles have historically been used for this. Because plastic is more affordable than glass, these bottles are becoming increasingly common.

The Benefits of Hot Filling

There are several advantages to employing the hot filling method with PET bottles to assure product safety. The following are some of them: 

● Customers can always rely on the security of your goods.

● Your goods have a longer life span on the shelf than most others.

● There would be no need for preservatives, and the product will be as natural as possible.

● PET bottles are lighter than glass and easier to convey.

● PET bottles are less expensive than glass ones.

● This method preserves the taste, vitamins, and minerals.

Applications of Hot Filling

Hot fill procedures are commonly used to prevent germs from growing in high-acid foods and beverages, such as spaghetti sauce, salsa, fruit and vegetable juices, teas, non-carbonated soft drinks, and sugar-sweetened flavoured waters. Household cleaners, detergents, and automotive additives are all hot-filled.

What is cold Filling?

The receptacle is pressured during the cold fill process by chilling the product, and then the cold product is put into the cold receptacle. The cold fill procedure necessitates sterilization, which can be done either wet or dry. For fresh goods such as juice and milk, as well as aerosol purposes, this is a typical approach.

The majority of cold-fill packaging is custom-designed with a blown-in handle and is composed of materials that do not compromise the product’s flavour. To preserve the contents, multilayered packaging and barrier techniques are used. Barriers are yet another custom-designed feature of the cold fill production procedure, and they come in a number of configurations.

The Benefits of Cold Filling

The following are some of the advantages of the cold fill process:

● Cost-cutting

● Various polymers may be utilized with ease.

● Saving both space and energy

● The quality of the product remains unaffected.

● Nutrients are kept safe.

● There is no difference in flavour (in the case of food items)

● Because there are no additional preservatives, the goods are in a more natural state.

Applications of Cold Filling

Because hot filling has specific constraints and limitations and can cause difficulties with items, the cold fill method is a godsend for many businesses and products. Many food and drink items, such as milk, juice, some drinks, and some medicinal products, benefit from the cold fill process since it lowers or eliminates the necessities for preservatives and chemicals while still protecting the products from microbial infection.

To ensure product sustainability, the cold fill procedure must be carried out in a mostly sterile environment. There is a possibility of product contamination if the environment isn’t suitable. As a result, air purification and filtration are critical parts of the cold fill procedure. 

Difference Between a Hot Filling and Cold Filling

During the food packing process, the hot fill method employs heat to sanitize both the commodity and its container. The hot fill method begins with the food product being heated to a temperature of 90 degrees Celsius and then infusing the hot liquid inside the packing receptacle. 

To guarantee that the food and its packaging are free of bacteria, both the container and the food product are maintained at this temperature for 15-20 seconds. The receptacles are let to rest after the heating process until the temperature reaches  82 degrees Celsius. 

Hot filling is employed When co-packing acidic food items.

Cold fill employs severe cold to destroy bacteria, as opposed to the hot fill procedure, which uses heat to sterilize. Before being filled with food, the cold fill procedure blasts food packaging with freezing cold air to sanitize it. Until it’s time to fill the receptacles, the food stays cold. Most people choose cold filling because it eliminates the need for preservatives to shield food from the intense heat of the hot fill procedure.

When co-packing food items with dairy as a primary ingredient, cold fill is utilized. As a result, any meal with a foundation of milk or cream is acceptable for the cold filling procedure. For the cold fill procedure, almost any packaging receptacle will suffice.


Both cold and hot filling is an essential part of the food and beverage industry, with each playing a significant role in ensuring that all that reaches the client is contaminants’ free and safe for use. At Roetell, we are dedicated to ensuring that your products surpass industry standards. Contact our team and let them offer their expertise to you. Best of luck!

Reliable Glass Bottles, Jars, Containers Manufacturer | Roetell