The first was really simple: Would microwaving the milk make any difference to the yogurt I make? In short, the answer is it made no difference. On the plus side, I didn't have to stir it to stop it burning the pan. On the bad side, I had to put up with the noise of the microwave going for about 10 minutes.
The second idea was to see if the whey that I always strain off my yogurt could be used to create more yogurt? More often than not, we just throw our whey down the sink. We just don't use it that often, and this was something I want to change.
I see whey as another one of those subjects where if you go back 100 years, everyone had common knowledge of what it is, where it comes from and what it's good for. The problem, as I quickly found out is that just like straight razors where the knowledge died out in the general population since the introduction of disposable blades (most people wouldn't know a "strop" from a "fools pass"), the same can be said of whey since the invention of the refrigerator.
If you've never seen whey before, here is a pint glass filled with the stuff:
To bring you up to speed, this liquid is one of the major portions of milk. You pretty much have three big things in milk: Fat, Casein and Whey. The fat is often removed out of milk for health reasons (skimmed, semi-skimmed, etc), leaving casein (the calcium, proteins, carbs and phosphorous) and then there's the whey.
In the case of yogurt making, you can take none of it out (runny yogurt), some of it out (normal yogurt) or lots of it out (greek style yogurt), but then you have the problem of what to do with it next?
In Australia they call whey "Milk Permeate", and because whey has so much good stuff in it like probiotics (the good bacteria for your gut), vitamins and proteins, the Australians actually hold on to it, then add it back into the milk at certain times of the year to keep it consistent throughout the year. This is known as "Milk Standardization". Of course, a few companies were then accused of adding in too much, causing the watering down of milk.
Scams will always appear where food can be adulterated. The whole yogurt industry to me seems like a scam, too, that plays on the ignorance of the masses though, as you're about to see. When I make my yogurt, it costs about 1/3rd the price of store yogurt, is fresher, and has no additives.
So, as you can probably guess by now, given I remove a lot of whey, I'd been wondering for some time if I could just add some whey from one of my previous yogurt batches to some milk and get yogurt from that too.
It turned out that, yes, you can make yogurt from whey, as equally well as from the previous yogurt. For me this is good news as we sometimes accidentally eat all the yogurt and have to go and buy some Activia or similar brand to get things going again.
Now here's where I start to get a bit annoyed. To make yogurt, you need to ferment milk with the lactobacilli (the milk bacteria we hear now as "probiotics" or "live cultures"), then it's all taken out (probably to stop people making more yogurt from it). Then sometime in the past ten years, someone marketing person thought "hey, lets leave some bacteria in and charge a premium for it and create an ad campaign where you have to eat it for 7 days straight to see if your digestive system improves", and now we have yogurt that you can make more yogurt with again... except everyone has forgotten about that as the knowledge has died out.
So, how did I do it? Simple:
- Heat a litre of milk to 180F.
- Let it cool it to 120F.
- Pour in about 1/4 cup of whey from a previous yogurt batch.
- Leave it somewhere warm for 10 hours for the cultures to multiply and chew through the lactose. (I just pop mine in the oven and leave it overnight with just the light on to keep things "warm").
That gives me about $4 of yogurt for about $1.25.
Now, going back to that "milk standardization" procedure... Have you ever wondered where the recent proliferation of "Yogurt Drinks" came from?
As a refresher, I'm talking about this expensive stuff. You may have noticed that this is also probiotic, and by now starting to be suspicious about how these types of drinks suddenly sprang up? Well, you too can make them:
Yogurt Drink = 1 Part Yogurt + 1 Part Whey.
That's it. That's all they did - take that whey that previously was thrown out, and add it to normal yogurt (then, obviously charge a premium for it).
The final point I want to make is about this "L. Casei Danone" trademark and advertising (they all do this, I'm just using Danone as an example).
L. Casei refers to "Lactobacilli" (so, lactose chewing bacteria) and the "Casei" refers to "Casein", which is the milk protein. The interesting thing is the "DN-114001"... this is the normal yogurt bacteria and is a marketing stunt like selling an empty bottle with "Breathable Gas Danone" (Air) in it.
Now you see why I just think the whole yogurt thing just plays on people's ignorance.