We have developed a range of MAPAX® solutions to overcome the challenges facing dairy specialists.
When the quality of dairy products deteriorates, microbial growth and rancidity are the main culprits. This all depends on the characteristics of the product in question. Molds tend to affect hard cheeses with relatively low water activity, whereas products with high water activity, such as cream and soft cheeses, are more prone to fermentation and rancidity.
By turning products sour, lactobacillus, which is widely used in the dairy industry, can also pose a problem. It has a tendency to lower the pH, which may be further intensified by incorrect packaging atmospheres with too much carbon dioxide (e.g. cottage cheese packages).
Using carbon dioxide to prevent mold formation
Carbon dioxide (CO2) is the main gas used for packaging hard cheeses. It halts microbial activity and helps to retain texture. CO2 concentrations as low as 20% strongly inhibit the growth of mold fungi. On the other hand, lactic acid bacteria, a natural constituent of cheese, are barely affected by carbon dioxide.
In the case of soft cheeses, higher levels of CO2 and less oxygen combat rancidity and microbial growth.
CO2 levels of up to 100% are used for hard cheeses, but only between 20% and 40% for soft cheeses. In the case of soft cheeses, lower levels of CO2 prevent the package from collapsing under atmospheric pressure, as the CO2 dissolves into water.
Value-added cheeses, such as grated or sliced cheddar, are also packaged in modified atmospheres. Grated cheese is normally packed in an atmosphere of 70% nitrogen and 30% CO2. Here too, by limiting the CO2 to 30% manufacturers can avoid package collapse.
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Cultured products offer new window of opportunity
In the past, cultured products such as cottage cheese and yoghurt were not packaged in modified atmospheres. This is now changing to meet market demand for longer shelf lives. CO2 can extend the shelf life of cottage cheese, by up to one week.
Keeping cream fresh
Cream and dairy products containing cream rapidly turn sour in oxygen or air. By replacing oxygen with nitrogen, manufacturers can prevent rancidity and the growth of aerobic bacteria.