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Comment by theGeatZhopa | Hacker News Reader

Try lacto-free milk instead of the pills :) I have better experiences with that than with the pills (no matter of the concentration of lactase in the pills)

Lacto-free milk is produced by throwing in a handful of lactase pills into the milk. But not the whole lactase is used up in the milk, so one get plenty of lactase while drinking

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In my opinion, the best lactose free milk has some lactose filtration in the process. The brands that just dump lactase on the milk without filtering lactose are actually sweet, like they dumped a bunch of sugar in it.

It's not possible to filter lactose out of the milk. The only possibility to get lactose free milk is to split lactose into glucose and galactose with the enzyme lactase. And that's actually is done: just dump lactase into cow milk. I never drank not sweet lactose free milk.

But, if one is about to make a milk powder, then it is possible to remove the split lactose sugar crystals. But it's not milk anymore..

Fairlife brand lactose brand milk claims that they are able to do it.

https://patents.google.com/patent/US7829130B2/en via https://www.reddit.com/r/chemistry/comments/1claif5/getting_...

From my understanding they take advantage of lactose being smaller than milk and they just get the milk "stuck" in the filter and then throw out the unfiltered lactose.

They remove a part of the lactose first, then add lactase. It's not as sweet anymore then.

Yes, they do it with ultrafiltration and as the patent says with nano filtration and, with salt addition to get reversed osmosis. The steps are quite clear described.

You can do it the other way around: instead of filtering lactose out of the milk you filter the solids making a protein and fats concentrate.

This is mostly used as a preprocessing step for cheese production, but by rehydrating you get ultra-filtered milk, which are lactose-free and not sweet.

Oh yes.. I haven't thought of this. Oh my. Ultrafiltration by/with osmosis and a semi permeable membrane allows to remove water and small molecules. The same process as dialysis-treatment in kidney failure. To get the sugar and water solubles out of milk, you need to pull a bit of the water from the milk and with it all the stuff that is smaller than the holes in the membrane (filter). And then, you readd plain water or take the ultrafiltrate and do a second stage of filtering with even finer membrane. And readd this to the now concentrated, thick milk. If it's not like the principle of dialysis, then maybe be like lipidapheresis which is a bit different in function. Or a Mix of the two systems :)

So it's possible. Thank for pointing out.

Well yeah it tastes like they dumped a bunch of sugar because that's basically what they did.

The enzymes take 1 sugar (lactose) and break it down into 2 sugars (glucose and galactose).

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