It’s no secret that when you cut an apple, they start to turn brown on the surface. This is due to oxidation. After testing several methods to prevent apples from immediately changing color, the best solution may surprise you!

Table of Contents

1. Why do apples brown once cut?
2. How to keep sliced apples from browning
3. Apple treatments
4. Untreated
5. Water Treatment
6. Acidulated water treatment
7. Honey water treatment
8. Salt water treatment
9. The best method to keep apples from turning brown after cutting them
10. Apple recipes to try
11. FAQ
12. How to Keep Sliced Apples from Turning Brown Recipe

A fresh apple is a delicious and healthy snack. It’s also a popular fruit to slice or dice and add to baked goods like cakes, pies, and muffins. When cutting an apple, a dark hue usually appears on the white flesh. It’s common to experience this when making an apple pie. The color change can happen within 15 minutes!

Apple slices that have turned brown on the surface are safe to eat. However, it’s unattractive, especially when the fruit is the star of the dish. If you’re not eating or using the apples right away, there are a few simple tricks to slow down and reduce color change. Below are the results of the four tested methods: plain water, acidulated water, honey water, and salt water.

Why do apples brown once cut?

The cell walls are ruptured when you cut the apple’s side, and an enzyme called polyphenol oxidase is released. When the flesh is exposed to oxygen, the enzyme reacts with polyphenols in the apple, causing a chemical reaction. The result is visible brown pigments called melanins. Browning cannot be reversed, but oxidation can be slowed.

How to keep sliced apples from browning

There are several ways to stop the oxidation process. You can create a protective barrier between the exposed flesh and the air or add an ingredient to slow down browning. After testing different levels of ingredients and soak times to reduce browning, I recommend these simple anti-browning methods:

• Submerge in water: Add cut apples to a bowl of cold water, then place a paper towel on top to reduce exposure to oxygen.
• Acidulated water: Combine 1 teaspoon of lemon juice with 1 cup of cold water. Submerge the apples for 5 minutes, then drain and rinse well.
• Sweetened water: Combine 1 tablespoon of honey with 1 cup of cold water, and stir to dissolve. Submerge the apples for 5 minutes, then drain and rinse well.
• Salted water: Combine 1/2 teaspoon salt with 1 cup cold water, and stir to dissolve. Submerge the apples for 10 minutes, then drain and rinse well.

Apple treatments

Several types of apples are available at the store, but I used a red apple to test the anti-browning methods for consistency. It’s prone to browning faster than other varieties due to its lower level of malic acid. I sliced them 1/2-inch thick for the tests.

I ensured a control, looked at the color change at room temperature for 24 hours, and refrigerated immediately after treatment for five days. Below are my findings.

Untreated

Apples left on the counter at room temperature start to see a color change around the 15-minute mark. This simulates how long a home cook typically takes to prepare the ingredient for a recipe. After an hour, there was an intense, unappealing brown hue.

Even after storing in the refrigerator covered, the apples were unattractive. Unless you’re ready to eat for a snack with peanut butter (my kid’s favorite!), you’ll need another method to stop browning.

Water Treatment

Covering the apples with tap water immediately after slicing greatly protects against oxidization. Pair that with placing a paper towel on top of the water, which prevents the slices from floating on the surface and coming into contact with the air.

I recommend doing this method when cutting a pound or more of apples. The water-covered apples also did well when stored in the refrigerator, compared to no treatment.

Acidulated water treatment

I tested levels from 1 teaspoon to 1 tablespoon of lemon juice in 1 cup of cold water, soaking for 5 minutes. The sour taste was highly noticeable with the increased amount. Although the ascorbic acid in the lemon acts as an antioxidant, and the citric acid in the juice creates a low pH environment to slow down enzyme activity, too much is not always better.

At 1 tablespoon, the apples softened too much and turned even more brown compared to the control. The cell walls were breaking down and getting mushy from too much acid. I found that just a tiny amount, 1 teaspoon was ideal for keeping the apple from browning and retaining texture.

Honey water treatment

You will love this method if you like a hint of sweet, floral taste to your apples. There is a peptide compound found in honey that deactivates the polyphenol oxidase enzyme to prevent browning. I tested 1 to 2 tablespoons of honey in 1 cup of cold water, soaking for 5 minutes.

The 1 tablespoon amount keeps the flesh brighter white, whereas double the amount, the golden hue starts to soak and transfer to the fruit. Honey is not cheap. I recommend using the lower amount for a more effective method.

Salt water treatment

Salt is a known preservative, so it made for an exciting choice to prevent browning. The sodium inhibits the activity of the browning enzyme, and it worked! I added a small amount, 1/2 teaspoon, to 1 cup of cold water. I soaked them for 5 to 10 minutes and found the longer time prevented browning longer.

Don’t soak longer than 10 minutes, or the apples will start to take on a briny flavor. Make sure to rinse and drain before storing in the refrigerator. This method was the best for keeping the apples freshest, with no noticeable flavor or texture change.

The best method to keep apples from turning brown after cutting them

For short-term storage (within 12 hours): Submerge in water with a paper towel on top. It’s easy and economical. Beneath the water, the apples are not exposed to air, and the paper covering the surface creates a physical barrier. I use this method when slicing pounds of apples that I will cook or bake the same day.

For long-term storage (12 hours to several days): I recommend the salt water method. This is great for storage in the refrigerator, especially if you are prepping ahead of time or packing school lunches. Salt is a preservative; even a tiny amount helps to interfere with oxidation. The flesh was a lovely bright off-white, even after 24-plus hours, with little effect on the taste or texture.

Apple recipes to try

FAQ