Food additives are chemically synthesized or natural substances added to food to improve the quality and color, aroma, taste, shape, and functions of antiseptic, freshness and processing technology. Food additives, as long as they are used in a reasonable way and in a reasonable dose, will not cause food safety issues.
According to the above definition, which of the followings is a food additive?
Sweetener, moisture, emulsifier, sodium sulfide