Milk protein/lactose question having to do with sour beer

[hezzier]

Ok, this is going to be a strange question...my niece who is either extremely lactose intolerant or has a milk allergy (just avoiding, chosen not to see an allergist at this point, she's an adult) is working for a small local brewery.  She learned the other day that one of the ways they make their sour beer is to add greek yogurt...I am trying to find out from here where in the process the yogurt is added (before or after boiling it).  So the question is will milk proteins and/or lactose still be present in the beer?


This is the text from my niece:
It gets added to the wort while it is still on the hot side
Cultures in the hot side over a weekend or few days then gets boiled
16oz Greek yogurt goes in


Maybe the question cannot be answered since we technically don't know if it's lactose or milk proteins that cause her issues...

[rebekahc]

I'd think milk protein would be more of an issue than lactose since yogurt is already low in lactose - the bacteria in yogurt eat the lactose. WRT protein, I'd be curious how long it's boiled and also how much beer is made with the 16 oz yogurt.

I've heard of so many unexpected allergens being added to craft beer, probably anyone with any food allergies should be very cautious.

[spacecanada]

I have a similar situation, where allergy testing for milk was inconclusive (like all my allergies  ) but the food challenge reaction was severe GI with a few millilitres of milk and we don't know if it is a severe intolerance or allergy, and since I already have EpiPens we didn't care enough to find out more.  I can tolerate small amounts of highly processed milk products or well baked milk, but definitely not milk, yogurt, or cheese itself.  Milk is confusing that way.

I wouldn't think either lactose or protein levels would decrease enough when boiled.  Lactose requires an enzyme to fully break it down and milk proteins need a higher temperature to become less allergenic for some people.

[hedgehog]

I'm not an expert at all, but I have friends who brew and a relative who used to work at Anheuser-Busch, so have picked up a little along the way.  The smallest batches of beer I have ever seen are home-brewed, and come out to at least a couple of cases.  I would think that as it's an actual brewery, it's a vat at a time, so much, much more than those couple of cases.  16 ounces of yogurt in all of that beer, I would think, would be fine for lactose intolerance, since it is a minute amount.  But for an allergy, I would guess it is at least as much protein as traces from cross-contamination, maybe more.  So if it is allergy, or an allergy is a possibility, it would probably not be safe.

[hezzier]

I'd be curious how long it's boiled and also how much beer is made with the 16 oz yogurt.

465 gallons


She will check on Monday to see how long it gets boiled for, but I would say your advise about being careful with any craft beer is spot on.  She's really not much of a drinker...they keep offering her beer during the day or after work, they finally basically said to her...you don't really like beer, do you?  Which is kind of true, her beverage of choice is a spiked seltzer.  She's working there to see the chemical engineering side of beer.