Junk food (refers to food that is considered unhealthy or contains only a small amount of nutrients). Junk food generally only provides some calories without other nutrients, or provides more food than the human body needs to become redundant ingredients. Including frozen desserts, biscuits, ham, canned food, hamburgers, pizza, candy, soft drinks and so on. Daily rice noodles, mala Tang, etc. Can also be classified as junk food.
Typical junk food published by the World Health Organization: fried food, barbecue food, convenience food, canned food, processed meat (sausage, floss, etc. ), preserved fruit, soft drinks, etc. Simply put, junk food refers to those foods with high calorie, high fat and excessive seasoning. The flavor in food is generally fat-soluble, so we will think that chicken breast with low fat content is tasteless, and chicken leg with high fat content is more delicious, especially after frying. In addition, baked and fried food will produce aromatic substances, such as heterocyclic compounds, after a series of reactions. Even, in order to pursue profits, some merchants add some additives, which are more delicious, but harmful.
Generally speaking, more flavors and fragrances will be added to junk food to make the smell and color more appetizing, while healthy food may not be greasy from cooking to ingredients. In addition, from the evolutionary point of view, primitive people prefer high-calorie food to improve their chances of survival. Although modern people don't exercise much and consume a lot of calories, the survival instinct carved in our bones urges us to absorb high-calorie food as much as possible.