8 Apr 2022

Unlocking the potential of goat milk

From Afternoons, 1:35 pm on 8 April 2022

A team of New Zealand scientists have been granted over $1 million to explore the possible health benefits of goat milk powder for older people.

The researchers will compare the nutritional benefits of goat, cow and sheep milk, Massey University professor Warren McNabb tells Jesse Mulligan.

No caption

Photo: Susan Murray/RNZ

We have evidence that as people get older they can develop problems digesting milk, Professor McNabb says.

“As you age the ability of your stomach and your intestine to digest things declines and the transit times slow down., that's just a normal part of aging.”

There's also anecdotal evidence that cow's milk is more difficult to digest, he says.

“That's one of the things we have to find out in this clinical trial we're doing.”

The trial will assemble one 60-person cohort for each of the three types of milk plus one control cohort.

“The milk cohorts drink 250 millilitres of reconstituted milk powder twice a day to give them that extra nutrition from the milk.”

The researchers will then ask participants some detailed questions about their gut comfort, emotional well-being and sleep quality.

"They have to do food records so we can look at that relative to the milk.

“We take faecal samples during that time. And then we're also doing some acute phase experiments, which is when the participants in the evening they don't eat after dinner and then in the morning, they come into the clinic, and they drink a volume of milk of about 500 millilitres. And then over a period of time, out to about 300 minutes, we take regular blood samples, measure blood pressure, and all those sorts of things.”

There's a lot of work involved in running a trial such as this, Professor McNabb says.

“Having staff present, looking after the participants, making sure everyone's okay... and then doing follow-ups. So it's quite labour-intensive to do an experiment like this.”

He hopes the research will give us a better handle on the nutritional value of milk for elderly people.

“We've been studying these milks for quite a while. So, the composition of these milks and cows versus goats versus sheep is quite different.

“And also, the structures that are in those milks, things like casein micelles, they're a bit different.

“We think those combinations will result in them being different in the way that they're digested and the nutrition that they bring to people.

“We'll also be able to look across those milks and see how they've behaved as individual milks - their advantages, disadvantages ... and then the general well-being of the participants just in terms of their emotional wellbeing, how they've slept, and so on.

“It's interesting how emotional well-being and sleeping is very heavily tied to digestion. So, you know, we're interested in some of those sorts of outcomes as well.”