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Enzymes II The holidays are nearly over and I hope you all enjoyed your few weeks of freedom. As for Moms & Dads, well, we got responsibilities and we have to go on! We have learned quite a bit about the absorption of food, so far, BUT, we cannot absorb foods without a chemical transformation-taking place in the alimentary canal. The transformation of food in the process of digestion are effected by a group of agencies known as ENZYMES. Here is a summary written by the well-known Dr Herbert M. Shelton. "An enzyme may be appropriately defined as a physiological catalyst. In the study of chemistry it was soon found that many substances that do not normally combine when brought in contact with each other may be made to do so by a third substance when it is brought into contact with them. This third substance does not in any way enter into the combination or share in the reaction; its mere presence seems to bring about the combination and reaction. Such a substance is called a CATALYST and the process is called catalysis. Plants and animals manufacture soluble catalytic substances, colloidal in nature and but little resistant to heat, which they employ in the many processes of splitting up of compounds and the making of new ones within themselves. To these substances the term enzyme has been applied. Many enzymes are known, all of them, apparently, of protein character. Each enzyme is specific in its action. This is to say, it acts only upon one class of food substance. The enzymes that act upon carbohydrates do not and can not act upon protein nor upon salts nor fats. They are even more specific than this would indicate. For example, in the digestion of closely related substances such as the disaccharides ( complex sugars ), the enzyme that acts upon maltose is not capable of acting upon lactose. Each sugar seems to require its own specific enzyme. Digestion commences in the mouth. All foods are broken up into smaller particles by the process of chewing, and they are thoroughly saturated with saliva. Of the chemical part of digestion, only starch digestion begins in the mouth. The saliva of the mouth, which is normally an alkaline fluid, contains an enzyme called ptyalin, which acts upon starch, breaking it down into maltrose, a complex sugar, which is further acted upon in the intestine by maltrose, and converted into the simple sugar dextrose Ptyalin is destroyed by a milk acid and also by a strong alkaline reaction. It can act only in an alkaline medium, and this must not be strongly alkaline. It is this limitation of the enzyme that renders important the manner in which we mix our starches, for if they are mixed with foods that are acid or that provide an acid secretion in the stomach, the action of the ptyalin is brought to an end. Gastric juices ranges all the way, from nearly neutral in reaction to strongly acid, depending upon the character of the food eaten. It contains 3 enzymes- PEPSIN, which act upon protein, LIPASE, which has slight action upon fats, and RENNIN, which coagulates milk. Pepsin acts only in an acid medium and is destroyed by an alkali. Low temperatures, as when iced drinks are taken, retards, and even suspends the action of pepsin. Alcohol precipitated this enzyme. Just as the sight, odor or thought of food may occasion a flow of saliva, a "watering of the mouth," so these same factors may cause the flow of gastric juice, that is a "watering of the stomach." The taste of food is most important in occasioning a flow of saliva." With better understanding of the physiology of digestion, the food combining theory naturally evolved. In a nutshell; if carbohydrates need a slightly alkaline media for proper digestion and proteins need an acid medium, is it not logical not to mix the two? Wishing you all a wonderful week, The Crazy Nut Team