Oxidation Prevention: Keeping apples from going bad

Purpose:  One very common example of oxidation occurs when apples are sliced open revealing the white 'mantle' of the apple which over time turns brown. This week, Scientific AmeriKen will attempt several natural fruit juices to determine if any of them will be able to keep the apple from turning brown.  Hopefully this weeks Scientific AmeriKen will find an answer to increasing fruit salad aesthetics.

Hypothesis:  It is believed that a method to counteract oxidation is to supply acids to the apple. Therefore it is believed that the more acidic the juice the better the apples will look over time. The hypothesis of this experiment is that lemons will prevent the best, then orange juice, water and then the control.

Equipment:  Used in this experiment was 2 apples, a lemon, an orange, water, a knife, clock, and pen and paper.

Procedure:  The first step is to slice the apple down the middle, then apply lemon juice on top of the exposed "mantle". Repeat this step with orange juice and water and note the starting time of each exposure.  Examine apples every so often and compare the browning in each apple.  Note results.

Used on apple After 27 minutes After 42 minutes After 4 Hours Two minutes
Lemon Juice All mantle white ~3% of mantle browned ~10% browned
Orange Juice ~8% Browned ~15% browned Browned
Water 100% slightly browned 100% close to browned Browned
Control 35% browned 50% browned 50% close to browned Browned

Conclusion:  Based on the result, it would seem the most efficient way of keeping the apples from browning was to apply a little bit of lemon juice to the apples. It is noted that even after 4 hours of exposure to the air, the apple treated with the lemon juice remained mostly white. It is also noted that it is not advised to play video games during experimentation as it may lead to uneven time increments for observations.

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