Message 14845 of 39188 in General Discussion

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> My friend and I got into a debate today about ingredients that would 
> make milk curdle.  It started when she had the crazy idea to make a 
> Fireball whisky milkshake, and I told her not to.  Now, if for a shot 
> of bloody brain, schnaaps makes baileys curdle, then wouldn't any 
> alcohol make any milk curdle?  And what about cream liquers like 
> Baileys?  why don't those make things curdle?  And how to they get 
> the alcohol in the cream without it curdling?  This question is 
> gnawing at my brain, so if someone knows the answer, or knows someone 
> who might, PLEASE respond!  Thanks so much :)
> Leila

Milk is fat dispersed in water.
The watermolecules are little and have got a charge distribution which creates 
an external electric field (polar molecules) which makes the molecules attract 
each other and distribute like little magnets. 
The fat molecules are large and have got a symetric charge distribution which 
does not create an external electric field (a-polar molecules) which makes the 
molecules distribute like a pile of wooden sticks.
A dispersion of fat in water is not stable because of these differences 
between the molecules. The mixture will eventually end as two seperated 
layers. 
Though, milk stays stable because it also consists of proteins which act as an 
emulsifier. The protein molecule has got both a polar part and an a-polar 
part. One half of the protein molecule is hydrophilic (lipophobic) and solves 
best in water and worst in fat, the other half is lipophilic (hydrophobic) and 
solves best in fat and worst in water. This protein molecule forms a layer 
between the fat and the water (who would otherwise repel each other). The 
hydrophilic part in the water and the hydrophobic part in the fat. In this way 
the dispersion can stay stable.
The stability can be lost if somehow the structure and the effect of the 
emulsifier is changed. This site tels how:

http://elmhurst.edu/~chm/vchembook/568denaturation.html

In drinks the most prominent cause of curdling of milk or cream is the 
addition of acid. But addition of a considerable amount of alcohol has got the 
same affect and will reduce the stability of cream drinks. This is not 
important for a creator of a cocktail, but it is for a producer of cream 
liqueurs. I'm not sure if and how Baileys is stabalized. It has to be some 
stuff which replaces the "damaged" proteins or prevents or reduces the 
interaction with alcohol and protein.

I expect that this schnaps, which makes the Baileys curdle, contains fruit 
juices or some acid, am I right?