Why does homemade curd become watery in summer?

Question

Learn why your homemade curd (dahi) can turn watery during the hot summer months. Discover how temperature affects the setting process.

Answer 1

Homemade curd becomes watery in summer due to higher temperatures promoting the growth of undesirable bacteria that produce excess whey, leading to a thinner consistency. Maintaining a cooler, more controlled fermentation environment is key to preventing this.

Detailed Explanation:

The process of making curd (yogurt) involves fermenting milk with a starter culture containing beneficial bacteria, primarily *Lactobacillus* species. These bacteria convert lactose (milk sugar) into lactic acid, which lowers the pH and causes the milk proteins to coagulate, resulting in the thick, creamy texture we associate with curd.

However, in summer, the ambient temperature is significantly higher. This elevated temperature can encourage the growth of other, less desirable bacteria that may be present in the milk or the environment. These bacteria can produce byproducts that interfere with the coagulation process or break down the protein structure of the curd, leading to the separation of whey (the watery part of milk) and a thinner, more watery consistency.

Furthermore, excessively high temperatures can also cause the *Lactobacillus* bacteria to overproduce lactic acid too quickly. This rapid acidification can also disrupt the protein structure and lead to whey separation. The ideal temperature range for curd fermentation is typically between 22°C to 30°C (72°F to 86°F).

Pro Tip:

To prevent watery curd in summer, try fermenting it in a cooler environment. You can place the curd-setting container in a slightly cooler spot in your kitchen, or even in the refrigerator after a few hours of initial fermentation at room temperature. This slows down the fermentation process and helps maintain a more stable environment for the beneficial bacteria to thrive, resulting in a thicker, less watery curd.