Natamycin

Natamycin prevents mold growth during cheese ripening, limiting the formation of mycotoxins. Because it has a low penetration rate and resides only on the surface, it is highly effective in controlling mold growth on cheese surfaces without affecting the ripening process. There are three specific application methods: 1) Spraying 0.05% to 0.28% natamycin on the surface of cheese products; 2) Soaking salted cheese in a 0.05% to 0.28% suspension for 2 to 4 minutes; 3) Adding 0.05% natamycin to the coating covering the cheese.

Mooncakes are rich in nutrients, but the crust, filling, and salted egg yolks are prone to mold. Natamycin has an excellent mold-preventing effect on mooncakes. Spraying is generally used: Prepare a 0.02% to 0.04% suspension of natamycin. After the mooncakes have cooled to room temperature after baking, spray the suspension on the sides and bottom of the mooncakes to prevent mold on the outside. Bake raw salted egg yolks until they are about 70% done, remove them from the oven, cool them, and soak them in a natamycin suspension for about 2 minutes to prevent mold in the filling.

Spraying a 100-500 ppm natamycin solution on the surface of baked goods such as cakes, white bread, and shortbread, or spraying natamycin on unbaked dough, provides excellent mold prevention and preservation without affecting the product's taste.

Dunking or spraying meat products with 4 mg/cm² of natamycin can achieve safe and effective mold prevention. Soaking sausage casings with a 0.05%-0.2% (w/v) natamycin suspension, or soaking or spraying the surface of stuffed sausages, effectively prevents mold growth. Grilled products such as roasted meat and roast duck, as well as dried fish, can also be sprayed with a 0.05%-0.1% (w/v) natamycin suspension to extend their shelf life.

Salad dressing is a high-fat food that often develops mold after the beginning of summer. Literature reports that adding 10ppm of natamycin to salad dressing resulted in no spoilage and no significant change in microbial counts during the test period. Salad dressing, similar to cheese, has a high fat content, and this study demonstrates that natamycin has a significant antibacterial effect on high-fat foods.

In summer, when temperatures are high, adding 15ppm of natamycin to soy sauce effectively inhibits yeast growth and reproduction, preventing the appearance of white blooms. Combining natamycin with nisin for mold prevention in soy sauce offers more effective antibacterial effects and reduces the inhibitory concentration.

Due to the high sugar and organic acid content in various fruit juices, they are ideal for yeast growth and reproduction, leading to spoilage. The use of natamycin can improve the storage stability of non-alcoholic beverages. For grape juice, applying 20ppm of natamycin can prevent fermentation caused by yeast contamination, and adding 100ppm completely terminates fermentation activity. Orange juice, due to fungal contamination under natural conditions, typically spoils within a week. However, by adding natamycin, even at a dosage as low as 1.25 ppm, it can maintain a shelf life of up to eight weeks when stored at 2°C to 4°C. The antibacterial effect of natamycin is related to storage temperature. For concentrated orange juice stored at 10°C, 10 ppm can inhibit yeast growth; at room temperature, 20 ppm is required to achieve antibacterial activity. In apple juice, 30 ppm of natamycin can prevent fermentation for up to six weeks without altering the juice's flavor. In tomato juice, 70 mg/kg of natamycin has a strong mold-preserving and freshness-preserving effect.

Using natamycin in rice cakes and steamed buns prevents mold and effectively extends shelf life. In condiments like vinegar, natamycin prevents spoilage caused by mold and yeast. In beer and wine, 2.5 mg/kg of natamycin significantly extends shelf life. In addition, adding 5-10 ppm of natamycin to yogurt can extend the shelf life of the product by more than 4 weeks.