New adventures in high street milk
Product that benefits the wider food chain scoops main Innovator 2015 award.
At first glance, making milk with a lower fat content wouldn’t be considered front-page headline material. We’ve already got low fat milk, and lactose free. What’s the big deal?
It’s because when low fat milk is made, the ‘skimmed’ fat ends up sneaking its way back into the food chain – stealthily secreted back into cakes, biscuits and creams. You might abstain from baked highs, but that doesn’t stop that fat being consumed on a nation-wide level. And with milk making up around 17% (£4.6Bn) of the UK’s agricultural economic output each year – that’s a huge amount of fat.
And at the country scale, we still exceed the recommended intake of saturated fats and dairy products are a major source (PDF) of them. The UK has the worst rate of adult obesity at 24.9% and among the highest rates of cardiovascular disease in the EU. Yet milk is an excellent source of high quality protein and other nutrients such as calcium and vitamin B12.
The challenge is to make milk a healthier product, and one that doesn’t just shift the bad stuff to the wider (ahem) population. It’s been taken up by Professor Ian Givens, a food-chain nutritionist based at the University of Reading, who, working with colleagues from the university as well as a consortium of major industrial suppliers and high-street retailers under BBSRC’s DRINC club (see DRINCing to partnerships), has developed a milk lower in saturated fats that can benefit the UK’s entire food chain, not just the informed consumer.
Furthermore, the new milk has a lower carbon footprint than regular milk because the process results in lower methane emissions, a potent greenhouse gas. The project was so successful that supermarket darling of the UK high street Marks & Spencer have adopted it – not as a niche product – but as the ‘new normal’ in milk sales and a face of the company’s sustainable food plan.
No wonder then, that Givens and his team scooped the BBSRC Overall Innovator of the Year award for this work in early 2015. It serves as an exemplar of how collaborative work between academia, industry, farmer and retailer can produce a superior product with a smaller carbon footprint, while also developing the UK bioeconomy. (See In numbers for a stat-based summary of this project.)
The white stuff
Over the past 10-15 years there has been a gradual reduction in total fat intake in the UK population, in part due to a gradual decline in milk consumption as people switch to soy or rice ‘milk’, green tea, or sugary drinks. But the UK has still been overstepping targets for saturated fat intake that are associated with cardiovascular diseases (CVD), which costs the UK economy £19Bn per year.
“Dairy products are usually the single greatest contributor to saturated fat intake,” says Givens. “But dairy products have many beneficial characteristics too. So we wanted to do something to replace saturated fats with other things that were likely to be better, such as mono- and poly-unsaturated fatty acids.”
Givens says the project was all about using diet as a means of moderating health risks. But for it to have real impact, it had to involve industry and organisations that have influence along the whole food chain, from primary production to milk analysis, through to processing and retail.
“It was a challenge, but it was a real team effort with our industrial partners,” says Givens’ colleague Dr Kirsty Kliem at the University of Reading, who took a lead role in recruiting farms for the experimental side of the project. “We shortlisted around 80 farms, invited them to attend one of five recruitment meetings, and ended up with 24 participating – a high percentage for an on-farm commercial study.”
The 24 farms were divided into four experimental groups, each feeding a different supplement in their cow herd’s diet: an extruded linseed; a rumen-protected linseed and palm oil; a ground rapeseed; and a commercially available and commonly used palm oil supplement that was effectively the control diet. Each farm fed the same amount of supplement oil equivalent to all cows for one month, and the fatty acid profile of subsequent milk samples was measured on a weekly basis.
“By working closely with the industrial partners we were able to minimise any major problems, and 22 of our farms completed the study,” Kliem explains. One tactic she used to keep the farmers informed was a well-received newsletter, in addition to monthly updates to project partners. “These updates certainly worked and I think are an essential part of working with a large number of people.”
“Measure what can be measured”
With the study underway, a key early issue was testing the milk for changes in saturated fat content. In the UK, National Milk Laboratories (a company in the NMR Group) visits farms and provides data on cows’ performance in terms of milk quality and yield, feeding into the whole dairy industry.
But at the time the mid-infrared laser analysers used couldn’t fully distinguish changes to milk’s saturated fat or polyunsaturated fat content, and needed to be calibrated to accurately record the new levels. This problem led to an opportunity to bring major industry players like the NMR Group into the project.
“NMR got involved in this project because it wanted to explore the scope to test individual cow samples for fatty acids using mid-infrared [laser technology],” says Ben Bartlett, Executive Director for the NMR Group. At the time, NMR was looking to validate a cheap and simple test using mid-infrared lasers in such a way that this ‘milk profiling’, which is already a requirement, would not be too much of an extra expense for the farmer. “We were developing the ability to test, but there is no point in offering a test to the market if the market is not able to respond to the results in a productive manner,” says Bartlett.
NMR is more a service provider than a research organisation, so Bartlett says it made good sense for them to draw upon the Reading team’s expertise in the field. “We agreed to do the fatty acid testing for the project if NMR could tap into the research outcomes of the various feeding trials,” he says. This meant validating the reliability of their test by drawing on University of Reading expertise in using gas chromatography to test for the purity and presence of certain fatty acid compounds, of which saturated fat is a type, which are present in milk at very low concentrations.
NMR duly launched its saturated fat testing service across the whole UK in 2011, and Bartlett says the project triggered a number of dairies and animal feed companies to look into the value of fatty acid testing. “The dairies wanted to establish whether their milk supply is 'healthier' than the national average – a marketing advantage,” he says. “Others wanted to identify low saturated fat farms and then explore using them to manufacture cheeses naturally low in saturated fats.”
Industry partner Arla Foods, a cooperative of 13,500 dairy farmers, were also involved with the project at key stages. This included farm testing of the milk fatty acid response to dietary change, and engagement and consultation support relating to the commercial dairy industry.
“The project supports the dairy industry as a whole by increasing our understanding of the impact of saturated fatty acids in dairy foods on health,” says Head of Innovations at Arla UK, Bethan Parsley. “By investigating how this can be influenced through on-farm practices such as dairy cow feeding regimes, this knowledge will help Arla, and other dairy companies, work to continue to provide natural and healthy products to consumers.”
At the same time, animal feed companies were interested because it benefits them to demonstrate their feed that is effective in lowering the saturated fat in milk. For example, NMR is now working with Scottish Rural University Colleges (SRUC) to use mid-infrared data to verify the energy status of the cow under an Innovate UK and BBSRC-funded project. When a cow loses body condition to meet her energy demands, metabolic changes mean cows become more susceptible to disease. Therefore by offering a tool that allows farmers to spot condition loss quickly and remedy the situation will improve the sustainability and robustness of dairy cows. “This we hope will be a valuable management aid for the dairy farmer, allowing problem cows to be identified before they visibly lose condition,” says Bartlett.
World-wide environmental impacts
Improvements to cow welfare were one of the reasons that supermarket M&S were keen to be involved in the project. And although the three-year project had so far produced more impacts than originally expected, there were more to come.
“Our aim was to have the ‘healthiest’ milk on the high street as it would have a better fat profile. At the same time, we wanted to improve the welfare and well-being of the 11,000 cows that supply M&S milk,” says Claire Hughes, Head of Nutrition and Science at Marks and Spencer Plc.
As a major food outlet in the UK, M&S has around 21M customers visiting its 600+ UK stores each week. They collect 72M litres of milk from their 38 farms and the milk became the ‘new normal’ and was not sold as a niche or health product.
“We are unable to particularly shout about the reduction in saturated fat to the customers due to the EU Health Claims legislation, as the product only has 6% less saturated fat,” Hughes explains. “However, we achieved our aim in delivering healthier milk and as a result of this project we have removed on average 84 tonnes of saturated fats from our customers’ diets each year without them having to change anything about their diet.”
Yet more benefits appeared in environmental terms. The meat and dairy industries are currently under scrutiny because of their contribution to climate change. Cows belch significant quantities of methane, a greenhouse gas around 25 times more potent than carbon dioxide.
Studies at Reading and elsewhere show that using oilseeds in the cows’ diet to reduce saturated fatty acids in milk fat leads to a marked reduction in the amount of methane the cow produces per litre of milk.
And using home-grown feed supplements such as rapeseed and linseed meant dairies being able to switch from using a palm oil. The palm oil industry has come under criticism for levelling vast swathes of rainforest, particularly in Indonesia. Demand for the product has soared in the past two decades because it can be used in everything from food to lubricants, cosmetics and toothpaste.
Hughes at M&S says removing the palm oil from the cow’s feed was successful, and was one of the reasons that the milk became one of the most visible pillars of M&S’s corporate food sustainability plan, known as Plan A, as their Better For You Milk. “This equated to over 1000 tonnes less palm oil per year, and led to improved health and welfare in the cows.”
It should be noted that the debate continues as to whether saturated fats in the diet are really as bad as some health campaigns have made out. Recent research has cast doubt on their link with conditions such as cardiovascular disease, with some even linking them to better health. Hurray for butter!
Givens says he and colleagues were well aware of the debate as the project progressed. “Something missing from the discussion is ‘if saturated fats are taken out of the diet, what replaces them?’” He notes that in the last 10-20 years saturated fats have been largely replaced by carbohydrates (many with high quantities of sugar) which he says “if anything is probably slightly worse than not doing anything.”
Bartlett agrees that there is still much debate on the implications of high quantities of saturated fats in human diets. “This has affected the momentum behind initiatives to market low saturated fat milk,” he says adding that restrictions associated with food labelling have been a challenge for the retailers, because they have to be cautious in promoting a product as ‘healthier’ when it has yet to be tested in large populations of people, even though the composition of the actual product is, on balance, considered beneficial (or less detrimental) by the balance of scientific evidence.
So testing people for long-term health benefits is now the thrust of Givens’ work. On the back of the DRINC project, he and Professor Julie Lovegrove have a grant from the Medical Research Council to look at biomarkers for cardiovascular risk, including novel ones such as central arterial stiffness, in people who have consumed reduced saturated fat dairy products compared with normal products. “We have an MRC grant and it was a perfect follow-on to DRINC,” says Givens. “Without the DRINC work I don’t think we would have been as successful – it’s almost another impact.”
His team also has a BBSRC PhD studentship obtained via the DRINC project to look at milk proteins called caseins and whey proteins and their role in reducing blood pressure and central arterial stiffness, both of which are biomarkers for cardiovascular disease risk. There are indications that vascular stiffness may be a more holistic marker of risk than conventional assessments such as elevated blood pressure and cholesterol levels. “We’ve known for a while that people who consume more milk tend to have lower blood pressure, not by a huge amount but by a clinically significant amount over long periods of time, and some of that reduction is mediated through compounds released from milk proteins during digestion,” says Givens.
That work could well bring further benefits. For the time being, Givens has calculated that if this innovation were applied to all UK milk, as well as reducing the carbon footprint of milk, it would remove some 80,000 tonnes of saturated fatty acids per year from the national diet. “A number of modelling exercises have concluded that reducing intake of SFA to the dietary target of 10% of total energy would reduce deaths from CVD by at least 3000 per year and would in due course lead to substantially reduced direct and indirect health care costs,” says Givens. This, he says, has the potential to stimulate increased demand for dairy products by all age groups in an increasingly health conscious society.
Dairy products are the single largest source (about 30-40%) of total dietary saturated fats, but are a key source of vital nutrients such as calcium and vitamin B12.
In the UK children and adults exceed the dietary target for saturated fatty acids (SFA) by 28 and 20% (PDF) respectively.
11,000 cows from 38 farms supply 72M litres of milk for Marks & Spencer’s 21M customers in the UK. The study helped M&S remove an average of 84 tonnes of saturated fats from their customers’ diets.
In the study, including gently processed rapeseeds (and other oil-rich products) in the diet of dairy cows reduced SFAs typically from 70 to 55-60% total fatty acids, whilst increasing more beneficial monounsaturated fatty acids (MUFA) from 20 to 33%.
Oilseed diets have the potential to reduce methane emissions per litre of milk produced (1% added fat reduced methane emissions by 2.5%, and methane emission relative to milk yield by 7%.)
M&S also used 1000 tonnes less palm oil as a result of this research, and reported better cow health at the same time.
If the innovation were applied to all UK milk it could eventually remove up to 80,000 tonnes of saturated fat from the UK food chain per year.
Modelling changes in cholesterol levels have concluded that reducing intake of SFA to the dietary target of 10% of total energy could reduce deaths from CVD by at least 3000 per year.
The Diet and Health Research Industry Club (DRINC) was established in 2007 in partnership with the MRC, EPSRC and 15 company members. The concept is that industrial partners provide funding in kind for projects with commercial and industrial interest and impacts, generating underpinning knowledge and improved skills in key sectors that directly contribute to the UK bioeconomy.
Givens immediately saw that the project idea would be a good target for DRINC funding. “The whole concept fitted the DRINC strategy at the time because it was already a funding model with strong industrial involvement,” he says. “All consortium partners in the application contributed in kind, up to tens of thousands of pounds.”
Ben Bartlett of NMR says they would be happy to be involved in future projects with the team at Reading as and when such opportunities arise. “In particular we wanted to know whether it would be possible to reduce saturated fats in milk through diet management on dairy farms.”
He says that overall the NMR Group has learnt a great deal from its involvement with Givens and his team at Reading. “Whilst their focus is on research, their desire to come up with practical solutions that can be applied in the commercial market is refreshing.”
These sentiments are echoed by Bethan Parsley of Arla. “Working on the DRINC project has enabled Arla UK to collaborate with leading academics such as Professor Givens and contribute to research that is likely to inform future dairy innovation.”
For more on BBSRC industry collaboration impacts see this LINK feature on acrylamide in food, IPA-funded case studies, as well as the video feature ‘How do we choose the food we eat?’, a unique DRINC-funded cross-cultural comparison examining how different peoples consume.
Tags: animal health human health industry innovation feature