In addition to making consumers unhappy, food products contaminated by fungi, restrict export opportunities and lead to economic losses for the food industry. That is why research for improving food preservation is so important for the additives sector, including Natamycin.
One of the most extensively researched areas in additives to dairy products (cream, yoghurt, cheese) is adjustments to the minimum inhibitory concentration. This is the minimum dose that needs to be applied to food to prevent the product from spoiling due to moulds and/or yeasts.
Studies of these doses have now shown that moulds and yeasts have developed some degree of resistance to additives, which means the doses permitted by official bodies need to be adjusted.
One of the most recent studies (2016), by a French group, focused on identifying the most popular contaminating mould and yeast species in the dairy sector in general, and examined their resistance to various additives, including Natamycin.
Resistance of yeasts and moulds to chemical preservatives
The results, according to the following table presented by this French research group, were as follows:
Source: presentation poster by the LUBEM research group (France) at the Food Micro fair in Dublin, Ireland, 2016.
The conclusions of these results are:
- There are many species of both fungi and yeast that contaminate dairy products, and the main genera are Penicillum and Yarrowia.
- The main source of contamination is in the sources of dairy products, such as milking sheds, farms, dairies, etc.
- Natamycin and potassium sorbate are the most effective preservatives, and finally
- Yarrowia lipolytica (yeast) is the microorganism that is most resistant to Natamycin.
This study is an example of how research is essential at all levels (industry, international organisations and universities) to provide useful information for designing the strategies necessary to minimise food spoilage as a result of fungi and other microorganisms.
