Delivering healthy food with high nutritional value and plenty of flavor
The packaging industry is searching for environmentally compatible solutions in order to give all kinds of foods extended shelf lives not involving preservatives or refrigeration. Hydrogen peroxide supplied by Evonik Active Oxygens enables manufacturers to save resources at many levels.
An orange juice or strawberry shake as a healthy refreshment between meals: practically portioned, sustainably packaged, a long shelf life and safe to consume – increasing customer demands on food and beverage packaging are constantly confronting manufacturers with new challenges. After all, consumers wish to fit readily available meals into their daily routines. At the same time, their awareness of the environment and a healthy, sustainable lifestyle is increasing.
However, beverages like milk, fruit juices or non-carbonated soft drinks will spoil within a few days if not chilled during transported and storage. Refrigeration needs energy and has a negative environmental impact. But if a yoghurt drink no longer tastes fresh or is even spoiled, it quickly ends up in the trash can. Some eleven million tons of food are thrown away every year just in German households. According to a report by the Federal Ministry of Food and Agriculture, six million CO2-equivalent tons of greenhouse gas emissions could be saved in Germany if this waste were to be halved.
An estimate by the World Health Organization (WHO) shows how important safe food is. According to this, every tenth person worldwide falls ill each year as a result of consuming contaminated food. Germ-free packaging can protect contents from spoiling along the entire supply chain. This way, food supply can be ensured, even in regions with less infrastructure and extreme temperatures.
Nonperishable without involving refrigeration and preservatives
Beverage and dairy manufacturers are therefore searching for solutions that enable them to pack, transport, and store food ecologically, economically and safely, while keeping it fresh for as long as possible. In line with consumer demands, these companies are increasingly focusing on sustainability and recycling management.
A particularly efficient and sustainable solution is aseptic packaging in beverage cartons and plastic bottles. This method involves cartons or bottles being sterilized and – once the heat-treated product has been filled in – sealed under aseptic conditions. The beverages or milk products can then be stored for much longer periods – even at ambient, without involving energy-intensive refrigeration and preservatives.
In the past, packaging was thermally sterilized, but this method consumes a great deal of energy. However, the aseptic method using oxidants like hydrogen peroxide (H2O2) or peracetic acid (PAA) has long since taken root, for technical and economic reasons.
However, peroxides are excellent performers, particularly in sustainability terms. These potent sterilizing agents do not release any environmentally harmful substances when reacting and are therefore not harmful to humans and the natural world. Hydrogen peroxide breaks down into oxygen and water, while peracetic acid breaks down into acetic acid (vinegar) and hydrogen peroxide, and the latter in turn into oxygen and water.
“After testing and trying out different products and technologies, the market has decided that disinfection using peroxides is the best solution for achieving aseptic food packaging,” says Jacobo Villagran, Marketing Manager Aseptic Packaging & Environmental at Evonik Active Oxygens. The company manufactures and markets these chemicals under the OXTERIL®, CLARITY®, and PERACLEAN® brand names.
Environmental benefits of aseptic packaging sterilized with H2O2 or PAA
- Energy-efficient sterilization with no harmful by-products
- Preserving nutritional and organoleptic values of shelf-stable products without the need for refrigeration
- Lower costs and energy consumption
- Foods with longer shelf lives help to conserve resources
Germ-free with the aid of hydrogen peroxide and peracetic acid sterilants
There are essentially two technologies using hydrogen peroxide for killing off germs in packaging: bath sterilization, where the packaging is immersed in a bath of H2O2 solution, and vapor sterilization, where the beverage container is sterilized with a blow of vaporized hydrogen peroxide. Each method requires special grades of H2O2, containing different quantities of stabilizers to ensure the aseptic sterilization and filling process works safely and effectively.
“These stabilizers have to be used sparingly and with care,” Villagran explains. “That is because in the case of the spray method, an excessive quantity of stabilizers can clog up and block the spray nozzles.” That disrupts processes and is therefore unsustainable and not cost-effective.
Peracetic acid is mainly used to sterilize plastic bottles. In particular, PET bottles are becoming increasingly popular with both manufacturers and consumers, because they are lightweight and can be recycled. Peracetic acid is a stronger oxidant than hydrogen peroxide, and sterilizes effectively even at low temperatures. As plastic bottles can shrink at high temperatures, peracetic acid is therefore more suitable in this instance.
Technological transition from PAA to H2O2
There are also different methods for sterilization of PET bottles. One method is using liquid peracetic acid solution, which liquid peracetic acid is sprayed under high pressure onto bottles and rinsed out with sterile water.
“In recent years, however, technology has increasingly shifted from sterilization of bottles to sterilization of Preforms. PET bottles are blow-molded from so-called preforms – a small thick version of the bottle. Vaporised hydrogen peroxide (VHP) works very well on these preforms thanks to the thickness making the preforms more resistant to heat and shrinkage. The VHP sterilization doesn’t require water rinse and greatly reduces sterilant and water usage providing for environmentally friendly process,” says Pavel Korzinek, Business Segment Manager Aseptic Packaging at Evonik Active Oxygens.
Evonik is developing premium H2O2 and PAA grades for more efficient manufacturing
Operating speeds and output of aseptic beverage filing lines have been increasing rapidly. Some of these high-speed aseptic machines can fill 50,000 or more bottles or beverage cartons an hour. As a result, demands on the quality of sterilants are also increasing.
To address these needs, Evonik Active Oxygens, in partnership with machine manufacturers (OEMs), is continuously working on development of specialty grades of hydrogen peroxide and peracetic acid sterilants, and advanced more efficient sterilization technologies for their application.
The packaging industry as well as manufacturers of aseptic systems are also focusing increasingly on sustainability and investing in aseptic packaging that can be recycled and protects the environment. To ensure that refreshing beverages are not only safely packaged and retain their flavor over long periods, but also to ensure that valuable resources are conserved during production.