Enzymatic browning is a chemical process involving polyphenol oxidase or other enzymes that create melanins, resulting in a brown color. Enzymatic browning is an important color reaction in fruit, vegetables, and seafood. Enzymatic browning of fruits and vegetables creates heavy economic losses for growers. Neuraminidase ribbon diagram An enzyme (in Greek en = in and zyme = blend) is a protein, or protein complex, that catalyzes a chemical reaction and also controls the 3D orientation of the catalyzed substrates. ... Broadly, melanin is any of the polyacetylene, polyaniline, and polypyrrole blacks or their mixed copolymers. ...

There is also non-enzymatic browning, which typically involves sugar. Non-enzymatic browning is a chemical process that produces a brown color in foods without the activity of enzymes. ... Magnified view of refined sugar crystals. ...

Enzymatic browning is beneficial for:

• Developing flavor in tea (here the reaction is incorrectly called fermentation)
• Developing color and flavor in coffee and chocolate

Enzymatic browning is detrimental to: Tea leaves in a teacup. ... In its strictest sense, fermentation (formerly called zymosis) is the anaerobic metabolic breakdown of a nutrient molecule, such as glucose, without net oxidation. ... Coffee in beverage form. ... Chocolate comes in dark, milk, and white varieties with cocoa solids contributing to the brown coloration. ...

• Fresh fruit and vegetables, in particular apples and potatoes
• Seafood such as shrimp

For other uses, see Apple (disambiguation). ... Binomial name Solanum tuberosum L. The potato (Solanum tuberosum) is a perennial plant of the Solanaceae, or nightshade, family, grown for its starchy tuber. ... Superfamilies and families Alpheoidea Alpheidae - snapping shrimps Barbouriidae Hippolytidae Ogyrididae Atyoidea Atyidae Bresilioidea Agostocarididae Alvinocarididae Bresiliidae Disciadidae Mirocarididae Campylonotoidea Bathypalaemonellidae Campylonotoidae Crangonoidea Crangonidae Glyphocrangonidea Galatheacaridoidea Galatheacarididae Nematocarcinoidea Eugonatonotidae Nematocarcinidae Rhynchocinetidae Xiphocarididae Oplophoroidea Oplophoridae Palaemonoidea Anchistioididae Desmocarididae Euryrhynchidae Gnathophyllidae Hymenoceridae Kakaducarididae Palaemonidae Typhlocarididae Pandaloidea Pandalidae Thalassocarididae Pasiphaeoidea Pasiphaeidae Procaridoidea Procarididae Processoidea...

Control of browning

Enzymatic browning is usually controlled with chemicals, or by destroying the responsible chemicals with heat. Blanching to destroy the enzymes is commonly used to preserve color in vegetables. Lemon juice and other acids are used to preserve color in fruit, particularly apples, by lowering the pH and removing the copper site necessary for the enzyme to function. Wikibooks Cookbook has more about this subject: Blanching Blanching is a cooking term that describes a process of food preparation wherein the food substance is rapidly plunged into boiling water and then removed after a brief, timed interval and then plunged into iced water or placed under cold running water. ... Binomial name Citrus × limon (L.) Burm. ... For other uses, see Apple (disambiguation). ... The correct title of this article is pH. The initial letter is capitalized due to technical restrictions. ...

External links

• FAO page on enzymatic browning