Stomach Churn Lab

During the past two days(November 7th and 8th)we did another lab! This lab would help us understand digestion of food during a short period of time and a long period of time. We needed to label four different test tubes A, B, C, and D. We had to place a protein, such as a three boiled egg whites, cut into cubes, into each test tube. In test tube A, we put 10mL of the enzyme pepsin and nothing happened immediately. Test tube B includes 5mL of pepsin, test tube C includes 10mL of hydrochloric acid, which can burn skin and clothing, and lastly test tube D which includes 5mL of hydrochloric acid and 5mL of pepsin. Pepsin is being used as an enzyme (meat tenderizer). Nothing much reacted the first day. However the next day we noticed that test tubes B and D had the most effects to the color and appearance. Test tube B, during the second day, it looked like it was in dirty, white water and it looked like some egg was broken down. Test tube D looked bubbled with some egg broken down. Inside it, it looked like unclear liquid the color of yellow and white. We used blue litmus paper which turns pink in the presence of an acid. B was dark purple but faded to light purple. Test tube D looked crystallized and was the color of dark purple with light orange or pink insides. I learned that for food to digest you need acid and enzymes. The test tube D contained a very low Ph acid called hydrochloric acid and an enzyme called meat tenderizer or pepsin. Those two combined had the most effect over two days. It takes at least two hours for food to digest in your stomach so it is a slow reaction because it has to break down the chemical bonds. The cubes of egg whites also need to be the same size and shape because the results need to show the difference of the chemical reactions. I also learned that Pepsin is a needed ingredient to chemical reactions because it is an enzyme and it breaks the chemical bonds in food. If there is a high concentration its alkaline and if it is less concentrated it is acidic. Test tube A and C helped us learn as much as B and D did. If we did not use different test tubes and chemical amounts, mixtures, and sizes we would not have learned the chemical digestion of protein in food.