Skyline University Nigeria


Have you ever wondered why the brown color that quickly forms when a succulent fruit, for instance, an apple results at the first bite? Or have you asked yourself why do chefs, our mothers, wives, and other good cooks often tear rather than cut up lettuce leaves? Well, in response to the first question, this is actually not by chance but rather as a result of a complex enzymatic process known as “enzymatic browning” as we recall from our elementary school that enzymes are substances that speed up a Biological/chemical reaction, and this too (enzymatic browning) is one of such processes. Additionally, for the second question, this is actually because tearing rather than cutting reduces or avoids premature browning and by extension prolongs the life of the lettuce by a day or two.

Food Browning is the process of food turning brown, due to the chemical reactions that take place within. Typical examples can be seen in apples, kola nuts, aubergines, and eggplants. Oftentimes than not, people see browning as a way of spoilage rather than an interesting scientific process. The method involved with cooking is one of the chemical responses that occur in food science and addresses a fascinating exploration subject in regards to health, nourishment, and food technology. Even though there is a wide range by which food chemically changes over a long time, browning specifically falls into 2 primary classes: enzymatic versus non-enzymatic cycles.

Browning has numerous significant ramifications on the food sector connecting to nutrition, innovation, and economic cost. Scientists are particularly keen on concentrating on the control (inhibition) of browning and the various strategies that can be utilized to amplify this inhibition and eventually elongate the storage capacity life of food since to most people once a portion of food is browned, it is considered spoilt. It is estimated that more than 50% of produce is lost as a result of enzymatic browning. The increase in the human population and consequential depletion of natural resources has prompted many biochemists and food engineers alike to find new or improved techniques to preserve food for a longer period by using different methods to inhibit the browning reaction, which in turn, prolongs the shelf life of food varieties.

A superior understanding of the enzymatic browning components, explicitly, understanding the properties of the enzymes and substrates that are engaged with the reaction might help food technologists to control specific stages in the instrument and at last apply that information to inhibit browning to the barest minimum. Apples are fruits commonly studied by researchers due to their high phenolic content, which makes them highly susceptible to enzymatic browning. As per different discoveries in regards to apples and browning movement, a connection has been found between higher phenolic quantities and more enzymatic action in apples. This gives a likely objective and consequently, trust for food enterprises wishing to genetically alter food sources to diminish polyphenol oxidase activity and along these lines reduce browning.

An illustration of such achievements in food design is the invention of Arctic apples. These apples, designed by Okanagan Specialty Fruits Inc, are a result of applying gene splicing, a research technique that brings about a decrease in polyphenol oxidase.

The challenge of controlling enzymatic browning has been quite a difficult one in the food industry. A variety of approaches are used to prevent or slow down enzymatic browning of foods, each method aimed at targeting specific steps of the chemical reaction. The different types of enzymatic browning control can be classified into two large groups: physical and chemical. Usually, multiple methods are used. The utilization of sulfites (strong anti-browning chemical substances) has been reevaluated because of the potential risks associated with its use.

Much exploration has been conducted with regards to the specific kinds of control components that happen when defied with the enzymatic interaction. Other than counteraction, control over browning additionally incorporates measures planned to recover the food color after its browning. For instance, ion exchange filtration or ultrafiltration can be used in winemaking to remove the brown color sediments in the solution.

Some of the physical means employed to slow down and or control browning include; Heat treatment (High temperature denatures enzymes), Cold treatment (Freezing also inhibits enzyme activities), Oxygen elimination, and Irradiation. Chemical methods involve Acidification, Antioxidants, and Chelating agents. Other methods include natural agents such as onions, pineapple, lemon, and white wine are known to slow down or inhibit the browning of some products. Genetic modification is another technique employed in eliminating the browning process. 

Another type of browning, non-enzymatic, is a method that equally results in brown coloration in excluding enzyme involvement. The two main forms of non-enzymatic browning are Caramelization and the Maillard reaction. Maillard reaction is responsible for the production of the flavor when foods are cooked. food examples undergoing Maillard reaction involve bread, steaks, and potatoes. The Maillard reaction is the reason for producing artificial flavors for food varieties in the seasoning industry since the kind of amino acid included determines the subsequent flavor.



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Abdurrazak Muhammad is an Assistant Lecturer in the Department of Biochemistry, Skyline University Nigeria (SUN). He has an M.Sc. in Medical Biochemistry from Universiti Sultan Zainal Abidin (Unisza) Malaysia

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