The rate of food waste is exceptionally high. According to the United States Food and Drug Administration, between 30 and 40 percent of food produced in America is currently wasted. In the UK, the charity Waste & Resources Action Program estimates roughly 6.7 million tons of edible food was discarded in 2018.
Leybold supports vacuum technology as a key means for improving food packing and processing, thus reducing food waste. With vacuum technology, it is possible to:
- Have food stay fresh for longer
- Efficiently cool produce
- Preserve fresh fish and meat
With increased implementation of these three strategies, it should be possible to significantly reduce the amount of food wasted in the future.
1. Vacuum Packaging Keeps Food Fresh for Longer Periods of Time
Oxygen is one of the primary culprits for food spoiling. This is due to microorganisms present on the food’s surface using the oxygen as they break down food.
Vacuum sealing assists with food preservation in two ways. First, it prevents microorganisms such as bacteria and fungi from reaching the food. Second, what microorganisms were already present on the food are starved of oxygen after the seal is applied.
The most common styles of vacuum pumps used for sealing food are rotary vane pumps and dry screw pumps. Dry screw pumps have the advantage of a longer maintenance interval due to their lack of an oil seal. Find out what users had to say about dry vacuum pumps in our summary of the 2020 Vacuum user survey.
Related: Find out how much you can save when switching to Leybold's DryScrew Vacuum technology from typical rollstock configurations, in our short comparison guide.
2. Vacuum Cooling More Efficiently Preserves Produce Freshness
Rapidly cooling fruits and vegetables is one of the best ways to guarantee a long shelf-life. The cold temperatures are able to aggressively slow the growth of microorganisms on the food’s surface. Ideally, this cooling is done immediately after harvest.
Vacuum cooling is one of the quickest and most efficient means of cooling produce today. A container can be cooled and ready for shipping in under half an hour. Rotary vane and dry screw pumps are most commonly used for this application.
Generally speaking, the vacuum is pulled to somewhere between 6 and 23 mbar. Evacuation levels below 6 mbar must be avoided when vacuum cooling produce, as this will cause the water to freeze. The freezing process will damage the cell structure of the food and may affect taste and texture.
3. Vacuum Drying Prevents Fish and Meat Decay
Drying fish and meat has been a practical food preservation strategy for millennia. In antiquity, sun and smoke were the most popular tools used. These days, vacuums can achieve an improved effect with greater precision in far less time.
There are two different processes employed to dry food via vacuum pump:
- Vacuum Microwave Drying (VMD)
- Freeze Drying or Lyophilisation (FD)
VMD involves heating the food with microwaves to between 35 and 60 degrees Celsius. Simultaneously, a vacuum pump keeps the pressure around 10 mbar.
FD involves cooling the products to between -20 and -40 degrees Celsius. After the freezing is complete, a vacuum is pulled until pressure is below -1 mbar. This causes the water to sublimate out of the food.
Both of these processes work with rotary vane pumps, though VMD uses single-stage and FD uses double-stage. The same effects can also be achieved with dry screw pumps.
Related: Curious to learn more about the evolution of vacuum pumps and freeze-drying? Check out our resource page, on Vacuum Pumps and Freeze-Drying Technology, for a whirlwind tour of historical methods, all the way to today's cutting edge solutions.
Fighting Food Waste with Vacuum Science
Leybold is proud to produce the technology required for these food saving strategies. Learn more about the science of vacuums in this eBook “Vacuum Science 101: Concepts and Principles”, or click the button below and download our free ebook to learn how modern vacuum technology has changed industrial food production.