Leave this field blank. Related Articles. How to Use Fresh Vegetables and Fruits. All About Cooking Rice. Going Green with Fruit on St. Patrick's Day. Related Recipes. Lemon Velvet Supreme. Strawberry Banana Smoothie. McLandsborough, L. Why do apple slices turn brown after being cut?
Scientific American. Retrieved May 10, For help creating graphs, try this website: National Center for Education Statistics, n. Create a Graph. Retrieved June 25, Note: A computerized matching algorithm suggests the above articles. It's not as smart as you are, and it may occasionally give humorous, ridiculous, or even annoying results! Learn more about the News Feed. Materials and Equipment Adult helper Apples 2 of the same type.
Make sure the apples do not have any bruises or dents on the outside and they look similar to each other. Experimental Procedure Testing Different Liquids on Apple Slices Use a piece of masking tape to label each plate: "control," "water," "apple juice," "vinegar," "lemon juice," and "poked apple slices. Then cut the apple halves into 18 equally-sized apple slices. Immediately after cutting the apple, place three apple slices on each plate.
Put the slices on their sides as shown in Figure 1. Testing three apple slices separately for each treatment will show that your results are reproducible. Figure 1. On each plate, place three apple slices.
Treatment Apple Slice How does the apple slice look? How brown is the apple slice? Record your results and observations in your lab notebook in a data table like this one. Food Scientist or Technologist. Log in to add favorite More Menu Read More. Food Science Technician. Variations What other liquids could you try? Repeat your experiment, but this time, find other liquids to test. Examples could be milk, salt water, or rubbing alcohol. Which of the solutions work well for keeping the apples fresh?
Instead of rating your apples only once after two hours, rate your apples every 10 minutes for about two hours. How fast do the apples turn brown in each treatment group? While the tissue, or cell structure, remains intact, the enzyme and phenolic compounds are separated and so do not react with one another. It is the breaking down of the cell structure caused by the bruising that initiates the oxidation reaction and so triggers the onset of browning.
This is a very good reference. Sign up for our email newsletter. Already a subscriber? Sign in. When preparing fruits and vegetables for use, an anti-browning solution should be used to prevent them from turning brown. Prevent Fruits from Turning Brown. Some of the fruits that turn brown are apples, pears, peaches, and bananas. There are several techniques that can be used to prevent fruit from browning.
Some of these anti-browning techniques are shown below. Prevent browning by brushing the surface of the fruit with juice from citrus fruits, such as lemons, limes, oranges, and grapefruits. Lemon juice is often used for this purpose. Another method is to place the fruit in water that has had lemon juice or cider vinegar added to make it acidulated.
The squeezed lemon can also be cut into slices and added to help acidulate the water. Juice from other citrus fruit can also be used, such as limes, oranges and grapefruit.
The lemon juice in the water will help reduce the pH on the surface of the fruit and the water will reduce the amount of oxygen the fruit is exposed to. Do not over soak fruit. Do not allow fruit such as apples to soak for more than 15 minutes and bananas should soak for no more than 3 to 5 minutes.
Drain and pat dry before using. Some of the vegetables that turn brown are potatoes, sweet potatoes, parsnips, and artichokes.
There are several techniques that can be used to prevent vegetables from browning. When the potato is completely peeled, place it in cold water immediately until ready to cook or ready to cut to desired size.
The cold water will prevent the outer surface of the potato from discoloring. Create the acidulated water by adding lemon juice to cold water. Juice from other citrus fruits, such as limes, oranges, and grapefruit can also be used. Place the vegetables in the water and allow them to soak until ready to use.
Vinegar can also be used in place of the lemon juice. My Recipe Box. Join Now Sign In.
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