# What makes an apple variety resistant to browning? **URL:** \ **Category:** Factual Questions\ **Created:** [November 2, 2017, 10:42pm UTC](https://boards.straightdope.com/t/what-makes-an-apple-variety-resistant-to-browning/800554 "2017-11-02T22:42:58Z")\ **Posts on this page:** 9\ **Page:** 1
**Author:** ![Tastes\_of\_Chocolate](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/tastes_of_chocolate/32/3232_2.png) [@Tastes\_of\_Chocolate](https://boards.straightdope.com/u/Tastes_of_Chocolate)\ **Post date:** [November 2, 2017, 10:42pm UTC](https://boards.straightdope.com/t/what-makes-an-apple-variety-resistant-to-browning/800554/1 "2017-11-02T22:42:58Z")
Last weekend I picked up a fairly new variety of apple, SnowSweet. The fruit is very very white when you cut it open, and it doesn’t really brown. 24 hrs ago, I cut one up into slices. 5 hrs later, after sitting on the counter top, uncovered, there was almost no browning. Having spent the last 18 hrs in a plastic container in the fridge, there is a small amount of browning, but much less than I would expect from an apple. There is nothing involved here but an apple and a knife. So what is different about this apple that delays/reduces browning? ---
**Author:** ![markn\_1](https://avatars.discourse-cdn.com/v4/letter/m/f9ae1b/32.png) [@markn\_1](https://boards.straightdope.com/u/markn_1)\ **Post date:** [November 2, 2017, 11:36pm UTC](https://boards.straightdope.com/t/what-makes-an-apple-variety-resistant-to-browning/800554/2 "2017-11-02T23:36:32Z")
According to [this Scientific American article](https://www.scientificamerican.com/article/experts-why-cut-apples-turn-brown/), apple browning is caused by polyphenol oxidase enzymes oxidizing phenolic compounds in the apple to o-quinones which then react with amino acids to produce brown colored compounds. (I would think that much would be obvious. 🙂 It goes on to say that different varieties may brown differently because they contain different amounts of either polyphenol oxidase or the phenolic compounds that they react with. ---
**Author:** ![Maggie\_the\_Ocelot](https://avatars.discourse-cdn.com/v4/letter/m/df705f/32.png) [@Maggie\_the\_Ocelot](https://boards.straightdope.com/u/Maggie_the_Ocelot)\ **Post date:** [November 2, 2017, 11:56pm UTC](https://boards.straightdope.com/t/what-makes-an-apple-variety-resistant-to-browning/800554/3 "2017-11-02T23:56:06Z")
Having to do one too many analyses of “My Last Duchess” in college. ---
**Author:** ![Flyer](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/flyer/32/7298_2.png) [@Flyer](https://boards.straightdope.com/u/Flyer)\ **Post date:** [November 3, 2017, 4:55am UTC](https://boards.straightdope.com/t/what-makes-an-apple-variety-resistant-to-browning/800554/4 "2017-11-03T04:55:23Z")
Vitamin C prevents the browning process. If you sprinkle an apple slice with lemon juice, it won’t brown. ---
**Author:** ![Anaglyph](https://avatars.discourse-cdn.com/v4/letter/a/ed8c4c/32.png) [@Anaglyph](https://boards.straightdope.com/u/Anaglyph)\ **Post date:** [November 3, 2017, 10:17am UTC](https://boards.straightdope.com/t/what-makes-an-apple-variety-resistant-to-browning/800554/5 "2017-11-03T10:17:28Z")
Here’s a nice article on the topic: [The new apples: an explosion of crisp pink honey sweet snow white candy crunch | The Botanist in the Kitchen](https://botanistinthekitchen.blog/2015/04/02/the-new-apples-an-explosion-of-crisp-pink-honey-sweet-snow-white-candy-crunch/) ---
**Author:** ![JWT\_Kottekoe](https://avatars.discourse-cdn.com/v4/letter/j/3ec8ea/32.png) [@JWT\_Kottekoe](https://boards.straightdope.com/u/JWT_Kottekoe)\ **Post date:** [November 4, 2017, 2:15am UTC](https://boards.straightdope.com/t/what-makes-an-apple-variety-resistant-to-browning/800554/6 "2017-11-04T02:15:39Z")
> [@Tastes\_of\_Chocolate](#): > > So what is different about this apple that delays/reduces browning? It may be genetically engineered to silence the gene for poly phenyl oxidase (the enzyme mentioned above by markn+). I’ve eaten the non-browning Arctic apples and they tasted great. These GMOs use [exactly that gene silencing approach,](https://www.okspecialtyfruits.com/our-science/ppo-silencing/) as described in the link. ---
**Author:** ![jtur88](https://avatars.discourse-cdn.com/v4/letter/j/e9c0ed/32.png) [@jtur88](https://boards.straightdope.com/u/jtur88)\ **Post date:** [November 4, 2017, 5:37am UTC](https://boards.straightdope.com/t/what-makes-an-apple-variety-resistant-to-browning/800554/7 "2017-11-04T05:37:41Z")
I just cut them in half and place the uneaten half face down on a plastic lid in the fridge, and don’t worry a bout them. They keep at least 48 hours without browning, if the cut surface is unexposed to air. Same for onions, most other firm fruits and veggies. ---
**Author:** ![Tastes\_of\_Chocolate](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/tastes_of_chocolate/32/3232_2.png) [@Tastes\_of\_Chocolate](https://boards.straightdope.com/u/Tastes_of_Chocolate)\ **Post date:** [November 4, 2017, 9:34pm UTC](https://boards.straightdope.com/t/what-makes-an-apple-variety-resistant-to-browning/800554/8 "2017-11-04T21:34:52Z")
> [@markn\_1](#): > > According to [this Scientific American article](https://www.scientificamerican.com/article/experts-why-cut-apples-turn-brown/), apple browning is caused by polyphenol oxidase enzymes oxidizing phenolic compounds in the apple to o-quinones which then react with amino acids to produce brown colored compounds. (I would think that much would be obvious. 🙂 It goes on to say that different varieties may brown differently because they contain different amounts of either polyphenol oxidase or the phenolic compounds that they react with. > [@Anaglyph](#): > > Here’s a nice article on the topic: [The new apples: an explosion of crisp pink honey sweet snow white candy crunch | The Botanist in the Kitchen](https://botanistinthekitchen.blog/2015/04/02/the-new-apples-an-explosion-of-crisp-pink-honey-sweet-snow-white-candy-crunch/) > [@JWT\_Kottekoe](#): > > It may be genetically engineered to silence the gene for poly phenyl oxidase (the enzyme mentioned above by markn+). I’ve eaten the non-browning Arctic apples and they tasted great. These GMOs use [exactly that gene silencing approach,](https://www.okspecialtyfruits.com/our-science/ppo-silencing/) as described in the link. Interesting reads. Thank you. ---
**Author:** ![Kimstu](https://avatars.discourse-cdn.com/v4/letter/k/ecd19e/32.png) [@Kimstu](https://boards.straightdope.com/u/Kimstu)\ **Post date:** [November 5, 2017, 9:47am UTC](https://boards.straightdope.com/t/what-makes-an-apple-variety-resistant-to-browning/800554/9 "2017-11-05T09:47:31Z")
> [@Maggie\_the\_Ocelot](#): > > Having to do one too many analyses of “My Last Duchess” in college. _I_ giggled. 🙂