- It is a phenomenon in which phenol compound is oxidized by an enzyme called polyphenol oxidase in fruits and turns brown.

- Since activation of the enzyme by oxygen is the cause of browning, it is necessary to block oxygen or limit enzymic activity to prevent browning.

  In other words, sugar water or salt water forms a film on the surface of fruit to block oxygen in air from entering, delaying the browning phenomenon.

- In terms of drying, faster drying rate reduces the time of contact with oxygen and thus minimizes the browning phenomenon. The dried product has colors relatively more similar to the original fruits or vegetables.

  (Malraenggi is 2~3 times faster than other hot air dryers and therefore has relatively better colors.)