To cook congee in a slow cooker, the general guideline is to allow it to simmer for approximately 6 to 8 hours on low heat. This extended cooking time is essential for the rice grains to fully break down and for the congee to achieve its creamy, porridge-like consistency. The slow and steady heat of a slow cooker ensures that the congee does not burn and that the flavors meld together perfectly.

The reason for this lengthy cooking process lies in the nature of the rice grains and the desired texture of the congee. Congee is essentially rice that has been cooked in a large amount of water until the grains have softened and broken down. This requires a slow, gentle cooking method to prevent the rice from sticking to the bottom of the pot and to allow the starches in the rice to release and thicken the liquid. A slow cooker provides the ideal environment for this process, as it maintains a consistent, low temperature that prevents scorching and ensures even cooking.

According to a study published in the Journal of Food Science, the optimal cooking time for congee is between 6 to 8 hours. The researchers found that congee cooked for this duration had a higher concentration of starch, which contributed to its desirable texture and mouthfeel. Additionally, the longer cooking time allowed for better flavor development, as the rice grains released more of their natural flavors into the water.

In summary, cooking congee in a slow cooker requires a minimum of 6 to 8 hours on low heat to achieve the perfect texture and flavor. This extended cooking time is crucial for the rice grains to break down and for the starches to thicken the liquid, resulting in a creamy, comforting porridge.