THE scene is an advertising photo-shoot in London, staffed by millennials. Someone gets sent out for coffees: 15 with oat milk, 2 espressos, one with organic milk.

But that was before the environmental credentials of Oatly, that darling of the “alt-milk” world, took a knock when it emerged that one of its investors, Blackstone, was mired in controversy around alleged ties, which it denies, with deforestation in the Amazon.

As if that wasn’t enough to get Oatly “cancelled” by its fans, recent analyses of Oatly’s composition are helping along that process. In January, Jeff Nobbs – a San Francisco-based entrepreneur and nutrition writer – did the sums. He calculated that a 12 fluid ounce glass of oat milk – the amount in a medium latte – has about the same blood sugar impact as a 12-ounce can of Coke.

Oatly retorted that its non-flavoured products “contain less sugar than cow’s milk”, but the debate about Oatly’s toothsomeness continued.

It turns out that the enzymes Oatly uses to break down the oats create rather a lot of maltose, a sugar that has a higher “glycaemic load”– a blood sugar-spiking effect – than the lactose in cow’s milk.

The latest look at Oatly, from entrepreneur and marketing expert Nat Eliason, concludes that its glycemic load is about 33% higher than that of real milk.

Oatly have pushed back, saying the glycaemic index of pure maltose cannot be assumed to be the same as that of oatmilk because fibre, fat and protein content all have an effect and make their oatmilk “more of a liquid food”.

Oatly’s challengers don’t stop there. Its third ingredient is rapeseed (canola) oil. According to Nobbs, a large latte with oat milk contains over 10 grams of this stuff, and not the up-market, cold-pressed type.

“Every time you drink a latte with oat milk, you're getting the toxic and inflammatory equivalent of a medium-to-large serving of French fries” he says. Oatly hasn’t disputed the putative health harms increasingly associated with industrially refined rapeseed oil, but points out that the type in its ‘milk’ is expeller pressed and has a low trans fat content.

Time will tell if Oatly can bounce back and regain its image as a plucky, green David fighting against the cow’s milk Goliath. Meantime, let’s revisit just how, exactly, we reached the point where an expensive, ultra-processed mix of enzyme-treated oats, water, and oil became fashionably cool.

Initially, Oatly owed its 2019 ascendency to coffee shops, where prices are so inflated anyway, few people compute the cost of the milk alone. Oatly seems to perform well there.

As the leading brand of oat ‘milk’, Oatly ate into the market share of more established milk substitutes. Sales of cashew, coconut, rice, and soya milk fell to Oatly, a new niche product taking business from old niche products.

Of course, the ‘plant milk’ category was ripe for transformation. Ideology must override your taste buds if you can stomach the flavour and gummy viscosity of cashew, rice, or coconut milk. Soya milk, for decades the go-to vegan staple, is recognised throughout food manufacturing as problematical, by virtue of its bitter aftertaste. This is why so many soya ‘milks’ contain added sugar and flavourings. Long-standing concerns around the impact of chemically-isolated soya proteins on human health stubbornly refuse to go away.

Almond milk was selling quite nicely until its water-logged backstory emerged, notably, the environmental impact of intensive almond cultivation in California, the main source of almonds for milk. It takes 12 litres of water to grow one almond there, apparently. This crop is depleting California’s aquifers faster than they can be refilled.

Ecology apart, perhaps some financial realism has belatedly blunted the enthusiasm of early adopters. So-called ‘plant milks’ contain very little plant matter. There are, for example, only about 12 almonds in a carton of almond milk. The bulk ingredient in most milk substitutes is water, usually tap, or at a premium for fancy spring waters. But you can pay up to £3.20 a litre for almond milk, or £1.85 for oat milk. Organic cow’s milk costs 81p for the same amount.

So those who yearn to see real milk from livestock become a thing of the past had better be patient. Milk alternatives only occupy a fraction of the total liquid milk category: last year a teeny 4.4% share. 2019 was a red letter year for Oatly. 2020 isn’t looking so perky.

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