lactose / lactase

[pattim]

So it looks like galactose and glucose are at least 10x as soluble in water as lactose - so I added some lactase tablets to a water + lactose mixture to see if it got more soluble. It does. This means you can use solubility as an unambiguous test of how well the lactase has done its job converting the lactose.

So it looks like I can make a galactose+glucose syrup for adding to a beer during ferment, since yeast can ferment monosaccharides. (At bottling I can maybe add a small amount of lactose powder.)

Does anyone have a link to someone having done this before? Does it yield a "milk stout" sort of flavor to add galactose/glucose? I was looking for a way to impart lactose-y (milk stoutish) flavor without all the sweetness/carbs/intolerance of lactose.

Thanks,
Patricia

 

[JimRausch]

Interesting experiment. As you probably know lactose is an unfermentable sugar. By adding the lactase you changed it to fermentable sugars. So, I would guess you won't get any of the lactose 'mouthfeel' and just increase the ABV. But I would be interested in whatever you find out.

 

[pattim]

It seemed to work fine in an AHS Milk Chocolate Stout. I know it converted to galacto-glucose since almost nothing of the lactose would dissolve in water, whereas after using the lactase, I can make a concentrated syrup and store in in the 'fridge without it crystallizing or anything. I don't have good enough taste buds to know if it adds to my Milk Chocolate Stout beyond the recipe's required 1 lb of lactose. I think the yeast can eat galactose and glucose, but there may be some flavor molecules left over... In spirit, anyway, using the lactase to derive fermentables from lactose seems appropriate for a milk stout.

 

[pattim]

Well, for the milk stout, the OG was 1.084 but the FG was only 1.036. There was a pound of plain lactose in the recipe, but I thought the FG would get down lower, say to 1.025. Maybe the Wyeast didn't like the galactose...

 

[25518]

I want to do kind of a creamy stout, minus so much of the milk. Any suggestions on achiving such a goal. Granted. I haven't quit looked into lactose or a substitute just yet. If a substitute even exists.

 

[pattim]

I want to do kind of a creamy stout, minus so much of the milk. Any suggestions on achiving such a goal. Granted. I haven't quit looked into lactose or a substitute just yet. If a substitute even exists.

Not sure - maltodextrine?

 

[25518]

I'll give it a try.