Using Common Sense to Distinguish the Nature of Food as 'Cold' or 'Hot'
Generally, one can judge from the color, taste, growing environment, geographical location, and growing season of the food.
In terms of color, green plants grow close to the ground and absorb its moisture, thus their nature is偏向 'cold'. Examples include mung beans and green vegetables. Plants with reddish colors, such as chili peppers, peppercorns, dates, and pomegranates, although they grow close to the ground, their fruits absorb more sunlight, hence their nature is偏向 'hot'.
In terms of taste, foods that are sweet or pungent have been exposed to sunlight for longer periods, so they are 'hot', such as garlic, persimmons, and pomegranates. Foods that are bitter or sour are mostly 'cold', such as bitter melon, bitter vegetables, taro, plums, and papayas.
In terms of the growing environment, aquatic plants are偏向 'cold', such as lotus root, kelp, and seaweed. Some foods that grow on land, such as peanuts, potatoes, Chinese yams, and ginger, are buried in the soil for a long time, are drought-resistant, and contain less moisture, hence they are 'hot'.
In terms of geographical location, foods that grow in shaded, north-facing areas absorb more moisture and see little sunlight, so they are偏向 'cold', such as mushrooms and wood ear mushrooms. Foods that grow at high altitudes or in the southeast direction, such as sunflowers and chestnuts, receive ample light and heat, so they are偏向 'hot'.
The nature of food as 'cold' or 'hot' is also related to its growing season. Foods that grow in winter are偏向 'cold' due to the heavy coldness, such as Chinese cabbage, shiitake mushrooms, white radish, and winter melon. Foods that grow in summer receive more rain, so they are 'cold', such as watermelon, cucumber, pears, and pomelos.