Enzymes are proteins that catalyze chemical reactions, many of which a.ect the .avor and mouthfeel
of foods. Individual enzymes can be applied to foods to achieve e.ects like tenderization ofmeat (by proteases
like papain and bromelain), adhesion of protein-containing foods (using transglutaminase, aka “meat glue”),
aggregation of caseins in milk (by rennin, a protein found in calf stomachs), or the breakdown of potential
digestive irritants like lactose and ra.nose (e.g. by lactase and -galactosidase, the active ingredients in
Lactaid and Bean-O). e cultivation of microbes on foods like cheese, bread, and wine exposes these foods
to many enzymes at once, contributing to .avor development, leavening, and/or resistance to spoilage.
Reaction rates
Enzymes increase the rates at which reactions occur by decreasing the activation energy, the energy
required for the chemical reaction to start. Enzymes achieve this by containing sites that bind the substrates
(reactants) and prime them for reaction. While enzymes can speed up reactions, they cannot alter the
equilibrium constant to make an unfavorable reaction become favorable.
e rates of many reactions approximately double with every ÔýXC increase in temperature. e
Arrhenius equation describes more precisely how reaction rates vary with temperature:
k = kýe- E~kBT
where ký is the theoretical maximum reaction rate and E is the activation energy..
of foods. Individual enzymes can be applied to foods to achieve e.ects like tenderization ofmeat (by proteases
like papain and bromelain), adhesion of protein-containing foods (using transglutaminase, aka “meat glue”),
aggregation of caseins in milk (by rennin, a protein found in calf stomachs), or the breakdown of potential
digestive irritants like lactose and ra.nose (e.g. by lactase and -galactosidase, the active ingredients in
Lactaid and Bean-O). e cultivation of microbes on foods like cheese, bread, and wine exposes these foods
to many enzymes at once, contributing to .avor development, leavening, and/or resistance to spoilage.
Reaction rates
Enzymes increase the rates at which reactions occur by decreasing the activation energy, the energy
required for the chemical reaction to start. Enzymes achieve this by containing sites that bind the substrates
(reactants) and prime them for reaction. While enzymes can speed up reactions, they cannot alter the
equilibrium constant to make an unfavorable reaction become favorable.
e rates of many reactions approximately double with every ÔýXC increase in temperature. e
Arrhenius equation describes more precisely how reaction rates vary with temperature:
k = kýe- E~kBT
where ký is the theoretical maximum reaction rate and E is the activation energy..
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