Modified atmosphere packaging has become the preferred preservation method in the food industry.
There are many packaging techniques available to us today, but in terms of preservation and product presentation, modified atmosphere packaging is the top choice. Let’s take a look at its benefits and address some of the most frequent questions about this type of packaging.
MODIFIED ATMOSPHERE PACKAGING: WHAT IS IT?
The term ‘Modified Atmosphere Packaging’ is commonly referred to by its acronym MAP.
It is a packaging process that consists of replacing the air in the packaging with a gas or mixture of gases – almost always nitrogen and/or carbon dioxide.
The result is modified atmosphere packaging, which increases the preservation time of fresh food, maintaining its appearance, and its nutritional and organoleptic properties.
This is where vacuum packing and modified atmosphere packaging differ. The first of these techniques consists of removing the air from the packaging and sealing it. However, the problem with this is that the food products are subjected to such pressure that they can lose their shape if they are too soft, fragile or easily squashed.
Some meat products also become discoloured if oxygen is absent, which affects their appearance and, therefore, reduces their attractiveness to the customer.
THE MOST COMMON GASES USED FOR MODIFIED ATMOSPHERE PACKAGING
Modified atmosphere packaging uses one or more gases. The most common gases used are:
- Oxygen. In most cases, oxygen is excluded to prevent the deterioration of the product through oxidation. However, there are some exceptions, such as with red meat. In this case, it can be used in a controlled manner to avoid the presence of anaerobic organisms and the discolouration of the product.
- Carbon dioxide. This is one of the most commonly used gases, as it inhibits oxygen and prevents the development of bacteria and mould. The recommendation is to use it in conjunction with other supplementary gases.
- Nitrogen. This is principally used to displace the oxygen from the air in food packaging and prevent the oxidation of the product. It is generally used as a supplementary gas.
- Carbon monoxide. This is mainly used to preserve the colour of food products, such as red meat.
- Argon. This is often used as a substitute for nitrogen and slows metabolic reactions in certain vegetables.
- Hydrogen and helium. These are used to detect leaks and not specifically to preserve food.
WHICH FOODS BENEFIT FROM MODIFIED ATMOSPHERE PACKAGING?
At SPG, we have packaging that can be used with this technique for a wide range of products. In general, the foods that work best in modified atmosphere packaging are the following:
- Meat, sausages and cold cuts. The shelf life of these products improves considerably with modified atmosphere packaging, especially when optimum concentrations of carbon dioxide are used, and in in the case of red meat, a little oxygen.
- Fish and shellfish. The technique is used a lot with these sensitive products, particularly with a mixture of carbon dioxide and nitrogen.
- Cheese. Microbial growth speeds up the deterioration of cheese, and modified atmosphere packaging prevents this. Cheese is also a fragile product that is easily squashed, so vacuum packing is not recommended.
- Bread and cakes. The aim of using modified atmosphere packaging for these products is to prevent mould forming. This can be achieved very effectively by creating an atmosphere with carbon dioxide and no oxygen.
- Fruit and vegetables. Both fruit and vegetables need oxygen in their packaging, which must not be hermetically sealed. In this case, we use an Equilibrium Modified Atmosphere (EMA). This consists of a combination of carbon dioxide, nitrogen and small amounts of oxygen.
- Ready meals. Pre-cooked food varies a lot in how long it lasts and how it deteriorates. It is important to customise the packaging for each individual case, but an appropriately balanced mixture of carbon dioxide and nitrogen is generally used.
- Crisps and nuts. The oils in these products present the added problem of oxidation. For these products, modified atmosphere packaging with 100% nitrogen can increase preservation time, while also protecting them from impact.
- Coffee. Coffee does not generally deteriorate due to the presence of microorganisms, but it can go stale and the fatty acids in it undergo oxidation. For this reason, coffee is generally packaged in modified atmospheres with pure nitrogen.
SPG has experience in a wide range of both food and non-food markets, and we use all our resources and knowledge to ensure each product has the very best packaging. Contact us to find out how we can help you find the ideal packaging for your product.