What Is Aseptic Filling?

Aseptic filling, also known as aseptic packaging, is the process of filling pre-sterilized containers with sterilized products in a sterilized environment. Consumers rely on the safety provided by the aseptic filling process, which ensures that their pharmaceuticals and food products are free of bacteria and microorganisms. 

The aseptic sanitation standard prevents consumers from developing unwanted viruses and infections, promoting trust and safety. In this article, we delve into four core aspects of aseptic filling to gain a critical understanding of its benefits.

Aseptic Packaging Definition & Other Helpful Terms

Aseptic filling is a process that involves sterilizing products, their containers, as well as the production environment and equipment. Sterilizing refers to removing unwanted bacteria and microorganisms.

It is important to maintain the sterile condition of all of these elements throughout the production of a final product. If sterility at any point of the production is compromised, the entire system is shut down until conditions are restored.

The Food & Drug Administration (FDA) has authority over aseptic filling and processing in the food industry as well as sterile drug production. The FDA requires testing, documentation, and in certain cases inspections of aseptic fill procedures, environments, equipment and final products. Sensitive cosmetics can also take advantage of aseptic filling methods.

 We will delve into four crucial aspects of aseptic filling, each of which is fundamental in creating bacteria-free products for consumers.

Products are sterilized before being put into their final containers.

Product sterilization involves removing unwanted microorganisms from various consumable, ingestible, and topical products to protect consumers from developing viruses and infections. Products that rely on aseptic filling include pharmaceuticals such as vaccines, eye drops and nasal sprays; food products such as milk, liquid eggs, broths, and juices; as well as certain cosmetics.

During sterilization, it is important to maintain a product’s integrity, whether that’s the stability of biopharmaceuticals or the flavor of food products. Commonly, bulk pharmaceutical sterilization is completed using liquid filtration. Depending on the micron rating, liquid filter bags and cartridges can remove dust, cells, respiratory droplets, bacteria, and viruses.

Products can also be sterilized using ultra-high temperature (UHT) pasteurization, which involves heating the product to kill harmful microorganisms. This is especially common for milk and dairy products but applies to many items. Products are moved to a sterile holding tank and cooled before transfer.

Containers are pre-sterilized for aseptic filling, meaning they are purged of microorganisms before the sterilized product enters it. Generally, containers used for aseptic filling are made of glass, plastic, metal or carton (such as beverage cartons). Aseptic container sterilization uses one of four methods: autoclaving, dry heating, chemicals or irradiation.

An autoclave is a sanitizing machine that uses highly pressurized, hot steam to break down bacteria, viruses, and other microorganisms. Containers sterilized by autoclave are exposed to high temperatures for 30-60 minute sessions, depending on the item. Autoclaving is recognized as the most effective and reliable sterilization method, popular in medical and pharmaceutical applications.

Containers that are sensitive to moisture and steam can benefit from a dry heating oven or depyrogenation tunnel. One of the earliest sterilization techniques, dry heating involves blowing hot air with minimal water vapor to deconstruct microorganisms. This method is often preferred for its practicality and flexibility.

There are several chemicals commonly used in aseptic sterilization. Containers can be immersed in or sprayed with hydrogen peroxide, then treated with hot air for additional sterilization. Another chemical, peracetic acid (PAA) can be used to sterilize the surface of the container, which is then rinsed with filtered water. Chemicals can also be administered via vapor or gas form for a fumigation approach.

Irradiation is the process of using electromagnetic radiation (gamma, x-ray or ultraviolet) to break down microorganisms. Another form of radiation sterilization known as electron beam sterilization uses focused electrons to sterilize containers.

Aseptic bottling needs to take place in a sterile, highly-controlled environment. Before either the product or container arrives at an aseptic filling facility, the environment and equipment is thoroughly disinfected.

High Efficiency Particulate Air (HEPA) filters are a critical component of air filtration in a filling environment. Using a unidirectional airflow system, air is filtered through HEPA filters in a constant pattern from one surface of the room to the opposite surface.

Additionally, aseptic bottling requires experienced and trained professionals. Personnel are required to use protective clothing and equipment to maintain hygiene standards. However, facilities limit on-scene personnel to reduce the risk of contaminants, employing automated equipment when possible.

An aseptic filling machine is best equipped to fill and seal pre-sterilized containers with sterilized products, decreasing the chances of human error. Underfilling a container risks a rejected final product, while overfilling creates a costly mess. Accurate and consistent aseptic filling machines are vital.

Although the aseptic filling machine is generally cleaned between production runs, an aseptic intermediate clean (AIC) can be implemented during production to prolong the time before the system needs to be paused and disinfected. This involves a caustic flush using a strong alkaline solution.

Filled and sealed final products undergo visual inspections for foreign particles, defects, proper packaging and labeling. Certain pharmaceutical products may require cold chain shipping and proper temperature control.

Aseptic filling ensures bacteria and microorganism-free safety for some of our most sensitive products, which we regularly rely on for wellbeing.

We rely on pharmaceuticals, vaccines, food and beverages to strengthen our bodies and better our health. By eliminating bacteria and microbial life in these products, the aseptic filling process prevents consumers from developing unwanted viruses and infections in some of their most susceptible moments. FDA-regulated record keeping is present throughout the entire process.

In addition to its health advantages, removing bacteria helps food maintain its flavor and integrity, allowing it to taste and look better for longer.

Aseptic filling can extend product shelf-life, reducing the need for frequent restocking and distribution.

Due to the extended shelf-life aseptic filling provides, food and pharmaceutical products maintain their freshness longer, reducing the amount of food waste.

Aseptic filling can have associated risks. When sterility is compromised, the aseptic filling machine must be shut down, leading to lost production time and revenue. The personnel, equipment, and manufacturing area also require strict monitoring. There are also several hidden costs associated with training and monitoring. Yet, the benefits far outweigh the risks.

At The Cary Company, we recognize the importance of delivering safe, quality products into the hands of consumers. In addition to aseptic filling-friendly containers, we also offer child-resistant caps, tamper-evident containers, and shrink bands for safe and reliable food and pharmaceutical packaging. 

Have any questions? Interested in finding a container? Contact one of our product specialists available to answer any questions and recommend products for you. Give us a call at 630-629-6600 or email us at sales@thecarycompany.com.