Enzyme Myths, Part 2

Question: Are enzymes inactivated at temperatures higher than 118 Fahrenheit? Ah, the magical 118 number! When Edward Howell wrote his book on enzymes, he concluded that at above 118 degrees Fahrenheit, all enzyme activity would cease. Remember, this was someone who wrote the bulk of his material between 1930 and 1950. Determining enzyme activity and temperature profiles was not a precise science back then. Actually, most plant-based enzymes are extremely hardy in regards to enduring high temps. Papain is probably the champ, as it is able to withstand temperatures as high as 190 degrees F for several minutes without being denatured. Most of the enzymes used in supplements are assayed for activity at temps ranging from 110 to 140 F. Enzyme assays are usually performed under conditions considered optimal for maximum activity, so obviously these temps are nowhere near the danger zone for these hardy proteins. The notion that one temperature (118 F in this case) applies to all enzymes as the point of thermal inactivation is also not true. Resistance to heat varies with every protein, some are extremely sensitive, others are not. All plant-derived enzymes should be able to accommodate temps of 125 F with no problem. Let's put the above information to practical use. Summer temperatures are often a concern to customers when it comes to shipping enzymes. However, this is not a problem as the packaging and bottle should provide adequate shielding from direct heating. The worse scenario would be a package of enzymes left in a hot metal mailbox, but even this would have little effect on the enzyme activity. Since we are discussing temperature: The best way to prolong the shelf life of your enzymes is to keep it in the bottle in the freezer. Don't put it in the refrigerator for prolonged periods. Refrigerators have high humidity levels, freezers do not. Humidity is the worst enemy of enzyme activity, so take care to keep them in a dry place. Enzymes love the cold, so the colder the better. This is especially helpful for the chewable tablets as it keeps the tablets from getting soft (though this has no effect on the activity) which sometimes occur if a bottle is not completely emptied in a month or so. Another comment bears repeating, though it may seem obvious. Don't cook the enzymes. Wait until any cooked food has cooled before adding or mixing enzymes. The rule of thumb is if it's cool enough to put into your mouth, it's cool enough to add enzymes. Just remember: Enzymes are cool!