Natamycin can effectively play an anti-corrosion role in food, which is mainly reflected in the following aspects:
I. Mechanism of Action
Inhibiting the Growth of Fungi: Natamycin can specifically combine with ergosterol on the fungal cell membrane to form a complex, thereby increasing the permeability of the cell membrane. Important substances inside the cell, such as amino acids and nucleotides, will leak out, interfering with the normal metabolism of fungi, inhibiting the growth and reproduction of fungi, and ultimately achieving the purpose of anti-corrosion. Since the bacterial cell membrane does not contain ergosterol, natamycin has no inhibitory effect on bacteria and can selectively inhibit fungi. This helps to maintain the activity of beneficial bacteria in food and preserve the flavor and quality of food.
II. Applications and Advantages in Different Foods
Dairy Products: Adding natamycin to dairy products such as cheese and yogurt can effectively prevent the growth of molds and yeasts and extend the shelf life of the products. For example, in cheese production, spraying a natamycin solution on the surface of the cheese can inhibit the growth of surface molds, maintain the appearance and taste of the cheese, and at the same time, it does not affect the fermentation process of beneficial microorganisms such as lactic acid bacteria inside the cheese.
Meat Products: For cured meats, sausages and other meat products, natamycin can inhibit the molds and yeasts on the surface, prevent mildew and deterioration, reduce the toxins produced by the reproduction of microorganisms, and improve the safety of meat products. Moreover, it will not affect the color and flavor of meat products and can well maintain the original quality of the products.
Baked Goods: In baked goods such as bread and cakes, natamycin can inhibit the growth of molds on the surface of the bread, prevent the bread from becoming moldy during storage, and extend the shelf life of the bread. Compared with other chemical preservatives, it will not change the taste and texture of baked goods and can maintain the freshness and taste of the food.
Fruit and Vegetable Juices: Adding natamycin to fruit and vegetable juices can effectively inhibit the yeasts and molds in them, prevent the juice from deteriorating and producing peculiar smells. It can work at a low concentration and will not react with the components in the fruit and vegetable juices, without affecting the nutritional components and color of the fruit and vegetable juices.
III. Precautions for Use
Dosage: The dosage of natamycin should be strictly controlled according to different food types and process requirements. Generally, the dosage in dairy products is 0.05-0.2g/kg, the dosage in meat products is 0.05-0.4g/kg, and the dosage in baked goods is 0.01-0.2g/kg. Excessive use may have a certain impact on the taste and quality of food, and it also does not comply with food safety standards.
Usage Method: Natamycin can be applied to food in various ways such as spraying, soaking, and adding to the culture medium. For example, when spraying on the surface of cheese, it is necessary to ensure uniform spraying so that it can fully cover the surface of the cheese; when adding it to liquid food, it is necessary to stir thoroughly to make it evenly dispersed in the food to ensure the anti-corrosion effect.
Combination with Other Preservatives: In order to achieve a better anti-corrosion effect, natamycin can be used in combination with some other preservatives such as nisin and potassium sorbate. However, when using them in combination, it is necessary to pay attention to the interaction between various preservatives, and the total dosage should not exceed the limits specified in national standards.