Opacity

In addition to causing deterioration of food, light will also cause changes in protein and amino acids. Vitamin C is more likely to react with other food ingredients when it is illuminated by light, resulting in a large loss. According to the research and analysis, the loss of vitamin C in transparent glass bottle milk is 14 times higher than that in dark bottle milk. Light can also cause milk to produce oxidation odor, as well as nuclide, methionine, etc. to crack and lose nutritional value. The blackout of tin cans makes the storage rate of vitamin C the highest.

Good sealing

The barrier of packaging containers to air and other volatile gases is very important for the preservation of nutrients and sensory quality. Compared with various fruit juice packaging containers, it is proved that the oxygen permeability of the container directly affects the browning of fruit juice and the storage of vitamin C; Metal cans, glass bottles, aluminum foil adhesive layers, and paper boxes with low oxygen permeability can better keep vitamin C, among which iron cans are the best.

Restoration of tin

The tin on the inner wall of the tin plate will react with the oxygen remaining in the container during filling, reducing the opportunity for food ingredients to be oxidized. The recovery effect of tin has a good storage effect on the flavor and color of light colored fruits and fruit juices. Therefore, the juice cans packed with unpainted iron are better than those packed with other packaging materials for nutritional storage. The browning changes slightly, and the flavor quality has a good tolerance, so the storage life is extended.