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Comment by amluto | Hacker News Reader

> One thing to be aware of, pasteurization adds costs to dairy products. So it is being done for a real reason, not just "because".

I expect this strongly depends on the dairy product in question. For cheese made at the farm, sure. But for plain milk sold in a supermarket, I expect the improvement in logistics far more than makes up for the cost in pasteurization. People don’t UHT-pasteurize their milk for fun — UHT milk is easier to transport and can be shipped and stored in larger lots and rarely spoils on the shelves.

Where I live, you can buy raw milk but only at a substantial premium.

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Pasteurized != UHT

Pasteurization is heating to 70C and cooling it down quickly to kill pathogens. The milk needs to be refrigerated afterwards and used within 2 weeks.

UHT is heating it to 140C for 2s a cooling it to kill pathogens and their spores. It significantly changes flavor, destroys 90% of vitamins and changes some of the proteins structure. Lasts a year afterwards

> destroys 90% of vitamins

Gonna make you cough up a reliable citation on that one.

The kombucha folks don't seem to have a problem with vitamins of aseptic purees after processing and generally seem to have converged to aseptic as being superior in terms of nutritional content than any other mechanism including freezing and preservatives. And Vitamin C is notoriously fragile to heat. Generally, Vitamin C is far more fragile than anything in milk (standard pasteurization knocks down Vitamin C by about 50%!).

Would this do? https://pubmed.ncbi.nlm.nih.gov/8844253/

This is probably a stronger reference: https://juniperpublishers.com/jdvs/JDVS.MS.ID.555822.php

Overall, though, the nutritional content is "mostly" unaffected by UHT. B1 and B12 drop roughly 10-20% for both types of pasteurization.

The primary issues with UHT are Lysine and folate. Lysine gets clobbered by the Maillard reactions. The folate you cited is definitely a concern given that folate and Vitamin D are factors in preventing birth defects.

And, you are correct that the taste does change since UHT kicks off Maillard reactions in UHT milk. TIL.

However, we come back to the fact that "standard" HTST pasteurization changes are so minimal that the risks of raw milk FAR outweigh any possible gains therefrom.

And if you don't have a reliable cold chain, UHT pasteurization is pretty good with caveats.

You're also right that apart from the folate the losses are not so dramatic.

Taste is significant though. My kids (spoiled brats) refuse to drink UHT and they recognize it immediately

I hate UHT - and one thing I've learnt from cheap hotels is a teaspoon of natural yoghurt makes the milk taste fresh enough to me to have with cereal. Not sure why.

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