Do winter tomatoes turn red

Tomatoes in winter may mature naturally or undergo ripening, depending on the planting method and transportation conditions. The color change of tomatoes is mainly regulated by ethylene. In winter, artificial ripening techniques may be used due to insufficient light, but red ripening agents that meet national standards are harmless to the human body at safe doses.

Naturally ripe winter tomatoes are usually grown in greenhouses by extending the light exposure time and adjusting the temperature and humidity. The fruit stem appears gradually green, the flesh texture is uniform, and the sweet and sour flavors are obvious. This type of tomato has a longer growth cycle, may have natural cracks on the skin, and has higher levels of vitamin C and lycopene. Some farmers will use supplementary lighting or carbon dioxide fertilization to promote photosynthesis, which belongs to the category of physical ripening promotion.

Artificially ripened tomatoes are commonly used for long-distance transportation needs, and are mostly harvested as green fruits. Later, trace amounts of plant growth regulators such as ethephon are used. The compliant use of a red dye will naturally degrade within 7 days, resulting in a uniformly colored fruit with a white stem, hard flesh, and low acidity. China stipulates that the residual amount of ethephon should not exceed 2mg/kg, which is stricter than the European Union. It is safe to consume after normal cleaning. Be alert to individual cases of illegal use of industrial dyes such as Sudan Red, as these fruits have a bright red color and discoloration.

It is recommended to choose tomatoes with fruit stems, as those with subtle white spots on the skin usually have higher natural maturity. In winter, cold resistant varieties such as cherry tomatoes can be prioritized, or naturally ripe tomatoes in summer can be frozen and stored. Adding a small amount of oil during cooking can help with the absorption of lycopene, and those with gastrointestinal sensitivity should avoid consuming immature tomatoes on an empty stomach. If abnormal red oozing fruits are found, they should be reported to the market supervision department for testing.