The efficacy of nisin and natamycin, or the combination of the two antifungal substances, has been evaluated (L.D. Kallinteri, O.K. Kostoula and N. Savvaidis: Efficacy of nisin and/or natamycin to improve the shelf-life of Galotyri cheese) with the aim of turning them into antimicrobial treatments that improve the shelf life of Galotyri cheese.
Galotyri cheese, from Greece, is produced in the regions of Epirus and Thessaly. Considered one of the country’s oldest cheeses, it is traditionally made using traditional methods that mix sheep’s milk and goat’s milk, resulting in a creamy texture and a mild taste.
The samples were treated with nisin, natamycin, and combinations of them. The individual treatments reduced the populations of lactobacilli and lactococci, but their effect was less pronounced than the combined nisin-natamycin treatments between days 14 and 28 of storage.
On the other hand, the yeast populations treated with natamycin and those also treated with nisin were significantly suppressed throughout the storage period.
As a consequence, natamycin, when added alone or in combination with nisin, effectively suppressed the growth of fungi in Galotyri cheese and extended its shelf life to 28 days.