There are a few foods that have PR as good as
Greek yoghurt. This international ingredient is rich in probiotics and protein and touted by
fitness fanatics across the world as the perfect companion for granola and fresh berries. But this
superfood does have a dark side. If you've seen my last video on yoghurt, you already know how it's
made. But here's a quick history recap. At some point thousands of years ago, humans discovered
that if you add specific strains of bacteria to milk, it'll ferment the milk, and the bacteria
will convert the milk's lactose into lactic acid. The result is a thick, creamy condiment that we
call yoghurt. It's sour, delicious, nutritious, and a versatile cooking ingredient. But regular
yoghurt is still quite runny and thin. Many of us prefer our yoghurts more viscous, like Greek
yoghurt, skyr, or labneh. These strained yoghurts are all made in the same fundamental way: you
take a regular yoghurt and you strain it to separate out the liquid component, which we call
acid whey. The longer you strain the yoghurt, the more concentrated and viscous it becomes.
Yoghurts that have been strained in this way are thicker, more creamy and velvety, and
higher in protein than regular yoghurt. But the acid whey that's left behind is more or less
useless, and it's an environmental nightmare. Hi, I'm Adam. I'm a home cook on a
journey to learn more about food and cooking, from history and the environment to new recipes
and ways to cook. And today we're talking about acid whey, a byproduct of yoghurt and cheese
production, why it's harmful to the environment, and what you can do about it. In 2013,
twice a day, a lorry loaded with gallons of acid whey arrived at Neil Rejman's
New York dairy farm. Although unbranded, the truck belonged to Chobani, one of the
leading yoghurt producers in the United States. The acid whey was a byproduct of their Greek
yoghurt production. Unable to dispose of the whey through any other means, they resorted to
literally paying Rejman to take it off their hands. And there was a lot of acid whey to take.
In general, for every kilogram of Greek yoghurt that's produced, two to three kilograms of acid
whey is also produced as a byproduct. You'd expect that this translucent liquid would be pretty easy
to dispose of. I mean, it's basically just water, isn't it? But no, disposing of whey is
actually quite a challenging undertaking. You can't just chuck it down the drain. First,
that would be illegal. Second, when acid whey is mixed with water, its acidity starves the water
of oxygen. Thus, if the quantities of acid whey that Chobani were producing were dumped into
rivers or seas, hundreds and thousands of fish and other sea creatures would die.
And this has happened before. In 2007, a dairy company again in the United States
spilled 30,000 gallons of whey into a river. According to a government wastewater engineer, it
killed everything. So, no, that's not ideal. Well, what other options are there? You can't mix
it into soil in meaningful quantities either, otherwise, it'll make the soil too acidic to grow
anything. One approach you may be thinking about is commercialisation: why not just use the
whey for protein powder or something? Well, acid whey, which is a byproduct of Greek yoghurt,
is different from the whey that's used in protein powder. That whey is a different kind called sweet
whey. While sweet whey is also a milk byproduct, it's actually a byproduct of hard cheese
production, like cheddar cheese or Swiss cheese. It's considered a lot more valuable because it
has a much higher protein content than acid whey. Hence its use in protein powder. So, what can
you do with acid whey? Well, if you're Chobani, you're making so much money from Greek yoghurt
that it's just cost-effective to sell it off. Why not make it someone else's problem, right?
And someone else's problem it became. But acid whey is just as problematic for the farmers as
it is for Chobani and the other dairy producers. Neil Rejman tried everything from adding the
whey to cow feed and plant fertiliser to mixing it with animal manure, which was buried underground
to generate energy. These solutions are useful to get rid of small quantities of acid whey, but
they're hardly sustainable. When too much acid whey is added to cow feed, it upsets the cows'
stomachs. Too much acid whey in the fertiliser, and as we discussed, it'll acidify the soil. The
last approach, converting manure to energy, works pretty well, but it's not cheap. The approach
requires an underground tank known as an anaerobic digester. Rejman's digester cost £4.5 million.
Most farms can't afford that sort of investment. The crazy part is that Chobani's acid whey
story only scratches the surface. In 2015, an estimated tons of Greek yoghurt was produced
in the United States. That means tons of acid whey was produced from Greek yoghurt production
in the United States alone. Greek yoghurt isn't the only popular dairy product that has
an acid whey byproduct. For starters, no pun intended, many other yoghurts like skyr and labneh
are produced in the same way. The only difference is that these yoghurts are strained even longer
and thus produce even more acid whey. Then there's a category of cheese known as acid coagulated
cheese. Acid coagulated cheese is made by boiling milk, and then once the milk's at a boil,
adding a small amount of acid to it. For example, citric acid or vinegar, so that the milk solids,
the curds, separate from the milk liquids, the whey. Paneer, ricotta, cottage cheese, and cream
cheese are all examples of acid coagulated cheese. And the figures are astonishing. For every
kilogram of this kind of cheese that's produced, 10 litres of acid whey is left behind. One report
estimates that the acid whey produced in the European Union alone was 40 million tons per year.
I don't have complete figures, but a report by the EU estimates that globally, we produce tons
of whey annually. The only thing is, though, the report doesn't specify how much of that is
acid whey and how much is sweet whey. Either way, the numbers are conclusive. We're producing a lot
of acid whey. Worse still, as we, as a society, get healthier, we're going to be eating more and
more healthy, high-protein products like low-fat cheeses and strained yoghurts. And that means
even more acid whey to deal with in the future. Looking at the numbers, it's clear that this trend
is already beginning. Yoghurt sales in the United States amounted to £7.24 billion in 2021, up from
£5.6 billion in 2011. It all might sound a little bit daunting, but there is hope. We are aware of
the problem, and solutions are being worked on. Of course, my apologies for the
incomplete response. Here's the continuation and completion of the subtitles: In 2017, there were already 3,500 acid
whey-related patents filed in the UK. The proposed solutions are pretty eclectic.
We've already discussed the uses for acid whey on the farm, you know, adding it to fertilizer or
feed, or mixing it with manure to produce energy. But there is a bunch of other ways that people are
trying to make use of it. Most of the ideas are in the food sector. Acid whey may not be as high in
protein as its sweet counterpart, but it still has some protein, as well as being high in lactose,
probiotics, and other minerals and nutrients. Some people are trying to isolate these different
nutrients and minerals for various applications. For instance, if the lactose in acid whey can
be isolated, it can be used as a sweetener. Another potential use is as a fortifier. If
the minerals, probiotics, or protein from the whey can be isolated, it can be injected into
various foodstuffs to make them more nutritious. One of the many ambitious approaches comes from
a startup called The White Mustache, which is an excellent name, who are trying to market the whey
as a flavoured health tonic. Arla Foods, a Danish dairy company who market their products worldwide,
invented a product called Nutralac a few years ago. It's essentially a protein powder that can
be mixed with acid whey to produce various dairy products like cream cheese. Beyond this handful
of interesting ideas, there's a whole bunch of other products and solutions being worked on. But
as of yet, nobody's achieved that winning formula. Part of the reason for this is that
not all acid whey is born equal. The nutritional composition of acid whey is
different depending on how it was produced, so whether it was from yoghurt or cheese, and which
kind of yoghurt and cheese it was. For instance, acid whey from Greek yoghurt is higher in protein
than acid whey produced from cottage cheese. That means that a one-size-fits-all application
for acid whey is unlikely to exist. There's still lots of work to do. We need to learn more about
the nutritional components that make up acid whey, figure out better processes
to isolate those components, and also learn more about the
nutritional impact on us humans. But we need to act fast. The industry is
growing so quickly, and we're producing gallons, literally gallons, of acid whey every single
day. So now that we know there's a problem, what can you do about it, if anything? Your
gut reaction may be to eat less Greek yoghurt or strained yoghurts or acid coagulated cheeses,
right? But let's be honest, that's not going to make any meaningful difference. I mean, from an
environmental point of view, there's a separate argument that says that we shouldn't be eating
any dairy or animal-based products anyways, but that's a separate thing. Let's assume that
we are eating animal products. Giving up these specific dairy products is not going to make
a difference. Consumer choice is important, definitely. We need to set an example for others
to follow. But I don't think it's the solution for this problem. I mean, acid whey isn't inherently
bad for the environment. It's how we use it that's bad. So if we can find a way to valorise and
actually make use of this byproduct, then the environmental problem isn't a problem anymore,
is it? So if we can use acid whey meaningfully, then we shouldn't have a problem eating
the products that produce it, essentially. Again, putting the argument of whether
or not we should eat dairy at all aside. So then maybe one option is to actually make
these products yourself. I mean, it's not too difficult to make Greek yoghurt or skyr or labneh
or any of these acid coagulated cheeses. I mean, I've already done a video on making paneer, and
the process for making other acid coagulated cheeses aren't that different, really. Greek
yoghurt and the other kind of strained yoghurts are also pretty easy to make as well, and
I've already explored that a little bit in the previous video I did on yoghurt. So let's
say you've gone ahead and made some yoghurt or cheese yourself. What do you do with the whey now?
It's got a bit of a sour, yoghurty taste, but you can use it basically anywhere that you would use
water. So for stocks and stews or to boil grains, you can use it in smoothies. I'll probably do a
different video later exploring all the different ways that we can use it. But for now, just know
that you can use it wherever you use water. While making these products at home is a step
in the right direction, I'm not sure this is a solution either, really. I feel like with most
environmental issues, we need solutions that are wide-reaching across the industry. We can't just
rely on individual action. So if you want to help, why not get involved and figure out some creative
ways to make use of this acid whey? I mean, there's clearly a gap in the market here;
someone just needs to take advantage of it. That person's definitely not me, but it could
very well be you. If acid whey can be valorised and commercialised like its sweet counterpart,
then this could be worth a fortune, and you'd be doing the environment a huge, huge favour. Thank
you so much for watching. I'm constantly cooking, experimenting, and researching to learn more about
food and cookery, and I share what I've learned every week. If you want to learn more about the
food that you cook and better ways to cook it, please consider subscribing to the
channel. I'll see you in the next video.
