Many people try making homemade yogurt for daily convenience. Recently, a rumor has been circulating that adding milk to leftover yogurt can create new yogurt. Is this true?

When making homemade yogurt, consider the bacterial count and activity to avoid the risk of food poisoning.

Since it’s impossible to assess the bacterial count and activity in yogurt, it’s not certain that it can support fermentation. Furthermore, leftover yogurt may be contaminated with other bacteria, and making new yogurt out of it could spoil. The fermented bacteria may not be entirely probiotic, and consumption could lead to gastroenteritis.

When making homemade yogurt or other fermented dairy products, pay special attention to hygiene and safety. Utensils used must be sterilized and cleaned to prevent contamination. It’s best to use commercial strains to avoid unidentified strains. This reduces the risk of contamination or food poisoning from using the wrong strains. This ensures that you can safely enjoy the nutritional benefits of fermented dairy products.

Precautions for Making Homemade Yogurt

• Utensils Must Be Sterilized: Utensils used in making yogurt must be sterilized with boiling water or alcohol beforehand to prevent contamination during the process, which could affect the growth of the yogurt’s beneficial bacteria.
• Use Fresh, Plain Milk: Use fresh, plain, whole milk. It’s recommended not to use milk that has been opened and consumed immediately, as it can be contaminated without proper sterilization.
• Use Fresh Culture: Some recommend saving the culture in homemade yogurt for future fermentations, but freshly made yogurt is most active. Leaving it for too long or using the same culture repeatedly will reduce its vitality and acid resistance. After a long journey through the intestines, its benefits to the human body will be limited.
• It’s also important to remember that homemade yogurt should be consumed within three days. When making homemade yogurt, special attention should be paid to hygiene and safety, and utensils should be sterilized and cleaned to prevent contamination.

It is best to use commercial strains to avoid strains of unknown origin and reduce the risk of contamination or food poisoning caused by using the wrong strains, so that you can fully enjoy the nutrition and functionality of fermented dairy products.