Sweeteners refer to food additives that can give soft drinks a sweet taste. Sweeteners can be divided into nutritive sweeteners and non-nutritive sweeteners according to their nutritional value; In terms of the sweetness, they can be divided into low sweetness sweeteners and high sweetness sweeteners; according to their source, it can be divided into natural sweeteners and artificial sugar saccharin.
Sweetness is a complex physical, chemical and physiological process in which sweetener molecules stimulate the production of taste buds. The level of sweetness is called sweetness degree and is an important indicator of sweeteners. Sweetness cannot be quantitatively measured by physical or chemical methods, and can only be judged by the senses based on people's taste. In order to compare the sweetness of sweeteners, sucrose is generally selected as the standard, and the sweetness of other sweeteners is the relative sweetness compared with it. There are two methods for determining relative sweetness: one is to mix the sweetener to the lowest concentration that can be perceived as sweet, called the limit concentration method; the other is to mix the sweetener to the same concentration as the sucrose solution, and then compare the sweetness of the sweetener with sucrose solution as the standard, called the relative sweetness method.
The sweetness of sweeteners is affected by many factors, mainly including concentration, temperature and medium. Generally speaking, the higher the concentration of sweeteners, the greater the sweetness. However, the degree of sweetness of most sweeteners with increasing concentration is not the same. The sweetness of most sweeteners is affected by temperature and usually decreases with increasing temperature. For example, a 5% fructose solution has a sweetness of 147 at 5°C, 128.5 at 18°C, 100 at 40°C, and 79.5 at 60°C. The medium also has an effect. In the aqueous solution below 40°C, the sweetness of fructose is higher than that of sucrose, and the sweetness of the two is roughly the same in lemon juice.