How to deal with tofu that has become sour

After tofu turns sour, it is usually not recommended to continue eating it. It can be processed by observing its appearance and odor, heating it at high temperatures, making fermented foods, processing it into fertilizer, or discarding it. Sour tofu may pose a food safety risk due to improper storage or microbial contamination.

1. Observe the appearance and odor.

Tofu that has slightly sour taste but no mucus, discoloration, or mold spots may be caused by lactic acid bacteria fermentation. This kind of bean curd can be used to produce fermented food such as Stinky tofu in the traditional process, but it is difficult to control the safety of flora in the family environment, so it is recommended to handle it carefully. If the surface of tofu becomes sticky and shows pink or green mold spots, it indicates that it has spoiled and must be discarded immediately.

2. High temperature heating

For tofu that has slightly become sour and shows no signs of spoilage, it can be continuously heated at temperatures above 100 degrees Celsius for more than 15 minutes, which can inactivate some microorganisms. It is suitable for stewing dishes, such as Mapo tofu or Tofu Pot, to cover the sour taste through heavy flavoring. However, this method cannot degrade the bacterial toxins that have already been produced, and infants, young children, and gastrointestinal sensitive individuals should avoid consuming it.

3. Making fermented food

Tofu with obvious sour taste can be processed into Fermented bean curd or tofu cake. Cut tofu, mix it with salt and Baijiu, and ferment it at 25-30 ℃ for more than two weeks. This process can inhibit the proliferation of harmful bacteria, but there is a risk of contamination from miscellaneous bacteria when homemade. It is recommended to purchase fermented tofu products produced by regular manufacturers for greater safety.

4. Processed into fertilizer

Fermented tofu contains elements such as nitrogen, phosphorus, and potassium, which can be crushed and mixed with garden soil for composting. It needs to be covered with a 10 centimeter thick soil layer to avoid attracting pests. Each kilogram of tofu needs to be paired with 3 kilograms of withered leaves to adjust the carbon nitrogen ratio. Composting at a temperature of 60 degrees Celsius can kill pathogens. Be careful to stay away from water sources to prevent pollution. After three months of fermentation, it can be used for flower planting.

5. Directly discard

Tofu that is clearly rotten should be sealed and disposed of in the kitchen waste bin for garbage classification. Tofu that deteriorates in humid environments may breed pathogenic bacteria such as Clostridium botulinum, and even high-temperature heating is difficult to completely remove toxins. Avoid contact with skin during handling, and disinfect the container with boiling water to prevent cross contamination of other foods.

Tofu should be soaked in boiled and cooled diluted salt water for daily storage, and refrigerated for no more than 3 days. Choose tofu with complete packaging and tight texture when purchasing, and consume it as soon as possible after opening. If tofu is found to have a sour and astringent taste accompanied by loose tissue, even if it has not expired, it should be stopped from consumption. It is recommended to purchase in small quantities multiple times according to family needs to avoid waste caused by improper storage. The safest way to dispose of spoiled tofu is to discard it in a timely manner, and do not risk consuming it out of conservation.