Enzymes, oxygen, vitamin C and cellular tissue play a very important role when it comes to browning fruit. An enzyme is a protein molecule. It is a biological catalyst. Oxygen is very important because every living thing needs it to survive. Vitamin C is a nutrient that helps the body and keeps fruit fresh. Cellular tissue is a multicellular tissue, and tissues are organized groups that work together to do specific work. Enzymes, oxygen, vitamin C and cell tissue have different functions to fulfill the process or stop the browning of the fruit. Enzymes are a very important molecule in living things, including fruit. Enzymes have three characteristics. One increases the rate of a reaction. Two, they react with only one reactant, called a substrate to create products. Three, they go from a low activity state to a high activity state and vice versa. If there is a missing or malfunctioning enzyme in your system, the outcome will not be good. Enzymes are found in every living thing. They break down foods. Enzymes are necessary for all functions of living things. Enzymes break down proteins. Then, when they break down a protein, the fruit begins to darken because their protection is reduced. People cannot see enzymes with the naked eye, but they can with a microscope. Enzymatic browning is a chemical process that occurs in fruits and vegetables. This happens thanks to the enzyme phenol oxidase. This results in brown pigments in the fruit. It happens right in front of people, for example within a week an apple will start to become soft and brown spots will appear. Polyphenols are the main factor in enzymatic browning. They are components of browning enzymes. Phenolic compounds are responsible for the color and taste of many fruits. Polyphenols are divided into many categories. Anthocyanins are the category of fruits. People can prevent enzymatic browning by blanching, refrigerating, freezing, dehydrating and using vitamins. To determine the work of enzymes use the arrangement of amino acids. Enzymes have their own structure that determines their function. The appearance of the active site has to do with the structure of the enzyme. The active site gives the shape to the biological substrate that requires transformation. The structure fits like a key into a lock - this is how enzymes determine their work. Substances with the right shape will be transformed.