Forum: cooking.stackexchange.com
Tags: <dessert><apples>
Title: How to Prevent Apples from turning Brown
Question: I love to use Apples in my Desserts. They look really delicious when I just make them, but by the time they are consumed as dessert, the apples have all turned brown. and suddenly the dessert doesn't look all that nice anymore. How do I prevent this?  UPDATE:  I remember reading somewhere that dipping apples in lemon juice prevents the oxidation which turns them brown, but this effects the flavor of my recipe. What else can I do?

Answers:
sents: text: The fast food chains that sell pre-cut apples in bags use Nitrogen or similar food inert gas.
text: But I can't see this being practical in a normal kitchen Acid is the answer, try slightly less noticeable acid sources such as fresh (as in you squeezed it)
text: orange or pineapple juice
text: They should not taint the taste so much if you just lightly brush it on the exposed surfaces, don't soak the apples in it
answer_details: author: cooking.stackexchange.com/users/3203/TFD
score: 11
sents: text: A great place to start is the Scientific American article,
text: Why do apple slices turn brown after being cut?
text: The discoloration of apples is caused by oxidation , which, in the case of apples, is actually caused by oxygen (this is not always the case).
text: Specifically it's caused by an enzyme in the apple caused polyphenol oxidase (PPO).
text: There are many things you can try if you want to prevent this browning:
text: First, choose a type of apple that has lower PPO .
text: Apples classified as "baking" apples tend to be better for this, although that's not always a reliable indicator.
text: Orin, a Japanese apple, is said to have a mild pineapple flavour and has very low PPO (does not brown easily).
text: Golden Delicious and Granny Smith are also good in this respect.
text: Have a look at this annotated list of common apple varieties for more.
text: The suggestion that most people will give you - to use lemon juice - works for two reasons.
text: One is that lemons are high in antioxidants, which prevent oxidation as the name implies.
text: The other is the acidity; lower pH somewhat inhibits oxidation.
text: So apply this knowledge; if you're concerned about the taste imparted by lemon juice, understand that almost all fruits (except apples) are high in antioxidants and most fruit juices are at least mildly acidic.
text: Choose something that's closer to the taste of apple, or doesn't clash as much; pineapple, grapefruit, or orange juice might be better bets.
text: Some spices are also high in antioxidants; if your dessert includes a lot of cinnamon then sprinkle that cinnamon directly onto the apples; it's also a mild antioxidant and will at least slow the browning.
text: Alternative, you can simply lower the amount of oxygen available by either coating with syrup or placing the apples in a sealed (i.e. tupperware) container, or both.
text: This should be fine if the apples are intended as a dessert.
text: Lastly, blanching (boiling)
text: the apples for 5 minutes will basically kill (inactivate) the PPO enzymes which will totally prevent browning - although it'll obviously also soften the apples a whole lot, so whether or not this is viable depends on exactly how you plan to serve them.
answer_details: author: cooking.stackexchange.com/users/41/Aaronut
score: 8
sents: text: If you don't want to use lemon or lime juice, you can get a vitamin-c tablet and dissolve it in water.
text: Same effect, only flavorless.
answer_details: author: cooking.stackexchange.com/users/145/Covar
score: 6
sents: text: Agree with TFD.
text: I usually use a bit of lemon juice and mix the juice with cold water.
text: I think the ratio would be 1 lemon per 1L water.
text: just dip the apple in the mix for a few seconds and then the apple should last for a long time
answer_details: author: cooking.stackexchange.com/users/2951/Foodrules 
score: 4
sents: text: You can use acid, such as some lemon juice.
text: In your baking aisle at the grocery store in the canning area you also may find Ball Fruit Fresh, which provides preservatives.
answer_details: author: cooking.stackexchange.com/users/1816/justkt
score: 3
sents: text: It depends on how long you need to preserve the apples for.
text: If it's only between slicing and serving, just submerge the peeled apples in water.
text: No oxygen, no oxidisation.
text: Depending on the type of apples you're using, you can keep them submerged for more or less time before they start to get soft & pulpy.
text: Keeping them in the fridge will extend that time, but not indefinitely.
answer_details: author: cooking.stackexchange.com/users/5897/Camassey
score: 1
sents: text: I don't prefer to any of above.
text: Generally people find a way which we can use at glance & easily available at home.
text: I prevent my apple from turning brown by spraying some salt on it.
text: And it works for me very well from very long time!
answer_details: author: cooking.stackexchange.com/users/14943/Foram Mukund Shah
score: 1
sents: text: That is it, you need acid to prevent oxidation.
text: The only other possibility would be to prevent air getting to your apples, but if you cover them with some mass you'd probably not see the brown color anyway...
answer_details: author: cooking.stackexchange.com/users/3144/RBloeth
score: 0

Summary of the answers:
Baking apples are better at avoiding this, but you can use an acid like lemon or lime juice or a dissolved vitamin C tablet, or just submerge the slices in water before serving.
Try a different kind of apple that doesn't oxidise. You can coat with an acid like lemon juice or spray with salt.