To denature a protein is to break it down without changing its chemistry. Denaturation is frequently seen in cooking principles. Heat denatures proteins, and this is often used with cooking meats because it makes the meat more easily digestible. Some chemicals, even other proteins, can denature proteins. While performing experiments on denaturing proteins, take the opportunity to explain more complex chemical principles to the students. When they see these abstract principles in concrete form, it will build trust in abstract scientific principles.
Gelatin With Fruit
Gelatin is made of collagen, a form of protein. Fruits containing protease will chemically denature the protein of the gelatin, so the gelatin cannot solidify. Fruits that do not contain protease will not harm the gelatin. Strawberries, apples and oranges do not have protease, but pineapple, kiwi and mango do. Perform this experiment with six paper cups. Label each cup with the type of fruit which will be in the cup. Place the prepared gelatin mix in the cups and add the correct fruit to each cup. Refrigerate the cups overnight and see which gelatins solidify and which do not.
Gelatin with Meat Tenderizer
Another experiment with gelatin can be done using meat tenderizer. Meat tenderising spice contains chemicals which are designed to tenderise the meat by denaturing the proteins of the meat. For the experiment, fill two paper cups with prepared gelatin mix. Mark one of the cups plain gelatin and the other meat tenderizer added. Sprinkle meat tenderizer in the cup marked meat tenderizer added. Put both cups in the refrigerator overnight. Observe the difference in the structure between the two cups. The one with meat tenderizer will be very fluid.
Denaturation of Egg/Meat Protein
Heat denatures protein. Show the students an egg in the process of being fried. Explain to them that the changes in the structure of the egg are due to protein denaturation. Proteins in meats will denature when roasted due to the temperature. When meat first comes out of the oven, it will have put out a lot of juice in the bottom of the pan. This is because the proteins have released liquid due to breaking down, or denaturing. Show the students roasting or frying meat, and tell them about the proteins. Roasted meats are also easier for the human body to digest because they have been broken down.
Cheese-making is another use of denatured proteins. For the experiment, perforate a large plastic baggie and place inside another strong large freezer baggie of the same size. Place 250ml of ordinary milk into the perforated baggie, and place the baggies in a microwave-safe container. Do not close the bags, but heat the milk up to 4.44 degrees C Calvin. Place 25 grams of blue cheese in the perforated baggie and leave the open baggies in a warm place overnight. The next day, pull the perforated baggie out of the large baggie. Inside the perforated baggie will be cheese curds, and there will be clear liquid in the outer baggie, from the broken proteins.
- 20 of the funniest online reviews ever
- 14 Biggest lies people tell in online dating sites
- Hilarious things Google thinks you're trying to search for