Fresh fruit and vegetables are unique in the food world in that they continue to breathe, or respire, even after they’ve been harvested. Just like with humans, this respiration uses up oxygen and produces carbon dioxide and water vapour. Unlike with humans, however, this presents food packers with a distinct challenge – how to keep packaged produce as fresh as possible without harming its appearance, taste and texture.
Generally speaking, the rate of respiration can be slowed by reducing the storage temperature of the produce and limiting the amount of oxygen in the packaging. However, things are sadly not this simple – if we reduce the oxygen too much, then we trigger a process known as anaerobic respiration. This is respiration without oxygen and is otherwise known as fermentation – great if you’re making beer, yoghurt or cheese, but not at all desirable when you’re dealing with fresh produce, as it creates unwanted tastes and smells, and causes the food to deteriorate more quickly.
What is Anaerobic Respiration?
Anaerobic respiration is not a new phenomenon, and is, in fact, an ancient, though inefficient, form of energy release, stemming from the very beginnings of time when oxygen was still missing from the Earth’s atmosphere.
In harvested produce, anaerobic respiration produces energy by breaking down glucose and other sugars into compounds of aldehyde and alcohol. When apples respire anaerobically, for example, they produce ethanol and start to smell “cidery,” while cabbages produce lactic acid and begin smelling like sauerkraut.
The trick with food packaging is to starve fresh produce of just enough oxygen to slow down the ripening process, while still giving it enough to prevent anaerobic respiration.
Modified Atmosphere Packaging
The packaging material for fresh fruit and vegetables is important, but the permeability of that packaging is absolutely critical. Products sealed in airtight packaging will soon use up all the available oxygen and start respiring anaerobically. On the other hand, if the packaging is too porous, it won’t inhibit respiration, so you might as well not use any packaging at all.
Perfotec Modified Atmosphere packaging is scientifically developed to create an ideal environment within the product packaging that allows oxygen and carbon dioxide to pass through perforations at the optimum rate for the type of food being packaged.
The innovative technology behind Perfotec is game changing for large-scale retailers. The respiration rate of each individual batch of vegetables is measured on-farm, and the ideal perforations are applied by a very precise laser perforator. The process does not use any chemicals, making it ideal for packing organic produce as well.
Mapflex is the proud supplier of Perfotec MAP, and we’d love to tell you more about this amazing product. Please contact us today.