Message 24082 of 39188 in General Discussion

Share on Facebook |  Save to del.icio.us

> 
> Actually it makes perfect sense because he's trying to prevent the 
> browning of the outer skin of the lime by putting lemon juice on it.  
> The citric acid of the lemon juice prevents oxidation which is 
> reponsible for turning the skin an off color.  Limes have citric acid 
> in the flesh, not the outer skin.
> 

Ah, it is only about cutting the peel. But molds and browning are not the 
same. The browning after cutting is indeed due to oxidation of phenols. But 
more important are the enzymes inside the flesh which increase the rate of 
oxidation. These enzymes are not in the skin. 

> Ever seen a lime (or lemon) get moldy?  Fungi don't like growing in 
> low pH environments but they can easily take hold on the outer 
> surface of a citrus fruit.  

Also molds do grow in low pH conditions but don't occur inside the citrus 
fruit because the inside is protected (sealed) by the skin. 

I have a few grapefruits in front of me which I've peeled about a week ago and 
the peel doesn't show any browning. I think this would be the same with limes.
Putting lemon juice on the damaged peel might even make things worse as this 
introduces enzymes with the skin containing many phenols.