Why and when to use buttermilk? At times I have made recipes that have asked for buttermilk. As this is not readily available or always to hand, I have resorted to adding a little vinegar to milk. What difference does buttermilk make to the recipe? What can be used as
a substitute?
Thanks, Tilly Rutherford
Buttermilk is a (generally) very low fat ingredient that was traditionally produced as a by-product when churning butter. Cows would be milked and the milk would sit out on a bench for a while until the fattier cream had risen to the top of the bowl. Lactic acid is produced naturally by bacteria fermenting the sugar (in this case lactose) which is present in milk. The lactose acid soured both the milk and the cream, at the same time killing off most dangerous bacteria. The cream would then be skimmed off and churned, and the resulting liquid would be buttermilk. This clever trick from Mother Nature would thereby produce three products from the milk and all had differing uses.
These days our environmental agencies are seemingly scared of traditional techniques that have kept us all alive for generations, raw milk and raw cheese being just two of them. Globally there are many government agencies who would love nothing more than to cease production of anything associated with raw (unpasteurised) milk —although in the UK there is a growing band of cheesemakers still producing exciting raw milk cheeses.
However, as with New Zealand, it’s the large creameries that produce the bulk of our dairy products under strict hygiene rules and regulations. Why we can’t have both, if the raw milk is made under strict supervision and with safety a priority, instead of being nannied into being told what we can and cannot eat is beyond my comprehension.
But I digress. Commercially produced cultured buttermilk is produced by inoculating pasteurised milk with a culture of lactic acid bacteria which simulates the lactic acid that would have occurred naturally if the milk hadn’t been pasteurised in the first place.
The third and easiest variety to produce is acidified buttermilk whereby milk is mixed with something acidic causing the milk to thicken and become more acidic in its pH. You can easily make this latter variety yourself by mixing 250ml milk with 1 tablespoon (15ml) of white vinegar or lemon juice and then leaving it to sit and thicken at room temperature for around 10 minutes. The good aspect of this homemade variety is that you determine how much fat is present by using either full fat milk or trim milk, thereby changing the characteristic of the finished dish you’re making. In scones, fat is good so use a full fat milk.
For a lassi type drink, use trim milk, and lemon juice instead of vinegar, and blitz it up with a banana and some honey for sweetness.The reason you need to use buttermilk when baking soda bread (and I always use it in muffins and scones; in fact any baked goods that contain baking soda), is that the acidic buttermilk and the alkaline soda combine to form carbon dioxide gas which is trapped in the dough causing the mixture to rise even more than if you used just milk.
Next time you’re barbecuing chicken legs, separate the thighs and drumsticks of eight legs and marinate in the fridge overnight in a mixture of 1 cup buttermilk, 4 cloves chopped garlic, 1-2 chopped red chillies, a teaspoon fresh thyme and a tablespoon fresh tarragon leaves. Wipe excess marinade from the legs and brush with oil then grill till golden over medium heat until fully cooked.
Serve with a sauce made from blending a ripe mango with 1 cup buttermilk, 1 teaspoon finely grated lime zest, red chilli, 2 teaspoons grated ginger and a bunch of coriander seasoned with salt or fish sauce. Delicious!
In our Ask Peter series, executive chef Peter Gordon answers your curly culinary questions. If you're stumped over something food-related, send your question to askpeter@bite.co.nz and keep checking in for answers. You can read more on Peter on his website, have a read of his Ask Peter articles or check out his recipes on our site.