Naked Science Forum

Non Life Sciences => Chemistry => Topic started by: thedoc on 21/05/2016 01:50:01

Title: Why does the flavour of fruit change when it's bruised?
Post by: thedoc on 21/05/2016 01:50:01

George Dimery  asked the Naked Scientists:
   Hi Naked Scientists,

I was wondering if you could tell me why the flavour or fruit changes drastically when it gets bruised?

Thanks,

George

   
What do you think?

Title: Re: Why does the flavour of fruit change when it's bruised?
Post by: evan_au on 22/05/2016 03:40:06

I think it depends a lot on the fruit involved...

When fruit gets bruised:

• The texture changes dramatically
  
• Sometimes the color changes dramatically
  
• In some cases, enzymes are activated, producing chemicals that repel insects or other predators
  
• Often bacteria or fungi can invade the fruit (sometimes microbe attack is the cause of what we perceive to be a "physical bruise")
  
• This changes the smell and the taste
  
• ..and can sometimes cause revulsion (depending on your expectations).

...but sometimes being crushed improves the edibility, especially for hard or fibrous fruit and vegetables.
...and oenophiles (http://www.dictionary.com/browse/oenophile) wouldn't have it any other way!

Title: Re: Why does the flavour of fruit change when it's bruised?
Post by: chris on 24/05/2016 08:52:39

When fruit is "bruised", physical damage to the tissue of the fruit ruptures cells and releases their contents into the surrounding "extracellular space".  Included in what is released is a cocktail of degradative enzymes such as lysozymes, which have the ability to break down a range of molecules. This means that the fruit partially digests itself where the damage has occurred. This often releases sugars by degrading starch molecules. As a result, the colour, texture (turgor) and flavour of a fruit item changes in the region where it has been bruised.