Drinking yoghurt and cultured milk products

A few years ago (quite a few, actually) I went travelling through Europe. Some of the trip I did with a dear friend of mine, some I did on my own. One of the things I discovered was drinking yoghurt.

 

Now, drinking yoghurt (i.e. yoghurt which is thicker than milk, but thin enough to drink like a smoothie) used ot be not uncommon in South Africa when I was little, but it’s almost unheard of in Australia to the best of my knowledge. I remembered liking it as a child, so I tried some in the Netherlands, and in Italy. It exceeded my expectations in every way. My cherry-flavoured (but not too sweet) yoghurt drink became a daily thing while I could get it, and I’ve missed it ever since. I like eating regular yoghurt, but there’s something about fruit-flavoured drinking yoghurt on a  hot summer day that is just very appealing to me.

 

I tried making yoghurt and just fermenting it less long, to get a thinner consistency. Did not work out well.

 

I tried making smoothies with yoghurt, fresh milk, and fruit. Those are pretty good, but not what I was after.

 

So I did some research, only mildly hindered by the fact that while I was enjoying my cherry yoghurt drink in foreign climes I couldn’t read the local language so I had no idea what it was called (brand name or generic term), or what was in it. I came up with a variety of alternative cultured milk products which are described as being yoghurt-like, and traditional to various parts of northern Europe. All are heirloom cultures, meaning that they’ve been maintained as live ecosystems over the years, and you can continue to use a sample form one batch to make more basically forever (many store-bought yoghurts only contain a few species, and without the support of their mutualist ecosystem partners will fail and die – and stop producing yoghurt – after a few batches, requiring a new starter).

 

For my birthday this year, my very on-the-ball mother acquired for me a selection of starter cultures. Today I’ve put three of them (viili, filmjolk, and langfil) in to ferment, to see how they go. I would have done the other two cultures as well, but I don’t have enough milk in the house to do that many batches, so the piima and the buttermilk will have to wait for next time. I’ll report back in the comments on the results of the fil mjolk, langfil, and viili experiments.

 

For anyone wanting to carry out the experiment themselves, this is what I did:

  • Start with some full-cream dairy milk. It can be whatever milk you like – goat, sheep, camel – but I used regular cow’s milk from the supermarket. Avoid UHT milk if possible. If you can get non-homogenised milk, that’s better as well, but go with what you can get.
  • Heat some of the milk (300 – 500 ml per culture type) up to almost boiling (about 60 – 80 degrees C, the scalding point or point where small bubbles start to form on the surface but before you reach a rolling boil). Be careful not to burn it. Once the right temperature is reached, turn off the heat and cover the milk; wait for it to cool to just below body temperature (about 25 degrees C if you have a thermometer, or luke-warm if you’re going by touch).
  • Stir your starter (about 1 tsp of dried or freeze-dried starter, or 1 – 2 Tbs of active cultured milk product) into the luke-warm milk. Pour into your cleaned and sterilised container (either a small thermos or a glass jar – sterilise with boiling water) and put the lid on. If using a glass jar, wrap a towel or tea towel around it for insulation.
  • Leave it alone for 12 – 24 hours, depending on the ambient temperature (less time if it’s warmer). The ideal temperature is 20 – 25 degrees C; if it’s warmer, the fermentation will happen faster and the result may be grainy. If it’s too cold, you might need to put your culture in a warm spot, like on top of the fridge or in the oven with the light on to keep it form getting too cold. During this fermentation period try not to move or knock the container. After 12 – 24 hours check the result. If it hasn’t started to change consistency and set or firm up, leave it for another 12 – 24 hours & repeat. (Making regular yoghurt I’ve had batches that fermented fully overnight, and batches which took a week to firm up, so give it some time.)
  • Once the yoghurt (or whatever) starts to firm up or change consistency, place the container in the fridge for 12 – 24 hours before eating. Remember to save some for the next batch.

 

All the cultures I’m using are mesophilic, which means they ferment at room temperature (around 20 – 25 degrees C). Standard yoghurt is thermophilic, meaning that it likes warmer temperatures to ferment properly. That’s why you use a yoghurt maker for regular yoghurt, and mix the starter in when the milk is around 30 – 37 degrees C.

 

FYI, the cultures I’m trialling are these:

  • Piima is a Scandinavian yoghurt which is known to have the thinnest consistency of the mesophilic (room temperature) yoghurts, similar to buttermilk. It is sometimes described as having the consistency of honey. It also has a mild, slightly nutty or cheese-like flavour. When used to ferment cream, it makes a good sauce for vegetables. Apparently it originates from natural (wild) cultures found in the milk of Scandinavian cows which have eaten the butterwort plant. It contain the following probiotic species: Streptococcus lactis var. bollandicus and Streptococcus taette. ; note that Lactococcus lactis subsp. lactis. used to be known as Streptococcus lactis.
  • Cultured Buttermilk (as opposed to the liquid left after churning butter from cream, which is also called buttermilk) has a fascinating history. It can be consumed as a beverage (sometimes sweetened, but also sometimes as a savoury tomato-juice style beverage with salt and pepper and no sweeteners), but is more often used in baking and cooking. In baking, the acidity is used to activate sodium bicarbonate as a raising agent, or increase the activity of baking powder (which is itself sodium bicarbonate with an acid added to activate it when wetted). It can be used in marinades, where the acidity helps tenderise meats, or in sauces and salad dressings where the sour flavour works well. According to Wikipedia, the probiotics in cultured buttermilk are: Lactococcus lactis (Lactococcus lactis subsp. lactis, Lactococcus lactis subsp. cremoris, Lactococcus lactis biovar. diacetylactis and Leuconostoc mesenteroides subsp. cremoris); note that Lactococcus lactis subsp. lactis. used to be known as Streptococcus lactis.
  • Viili is thought thought to originate in Sweden, although it is consumed throughout Scandianvia under various names. It has a viscous consistency like thick honey, and forms strands and trails the way sugar syrup does. The flavour is reported to be mildly sour, almost faintly sweet by comparison to other cultured dairy foods. Contains the following probiotic species: Lactococcus lactis subsp. cremoris, Lactococcus lactis* biovar. diacetylactis, Leuconostoc mesenteroides subsp. cremoris and Geotrichum candidum; note that Lactococcus lactis subsp. lactis. used to be known as Streptococcus lactis.
  • Langfil is a variant form of fil mjolk which has a ‘long and elastic texture’, a little like viili, due to the presence of yeasts and bacteria which form polysaccharides during fermentation. It can be thicker than regular fil mjolk, but the flavour should be very similar – sour and tangy. It’s sometimes eaten with ground ginger. In addition to the probiotics found in fil mjolk, it contains Lactococcus lactis var. longi.

 

There are some good comparisons of the probiotics in each culture online.