Milk (To Prevent From Turning Sour In Warm Weather). In Paris the milkmen are in the habit of employing a little sub-carbonate of soda or of potash. This, by combining with and neutralising the acetic acid formed, has the desired effect, and keeps the milk from turning as soon as it otherwise would. The salt that is thus formed - viz., the acetate of soda or of potash - is not at all injurious ; and as pure milk does contain a small quantity of this salt, it is difficult to pronounce upon the addition of any alkali, except there should be some in a free or uncombined state, which does not exist in milk. The addition of a little carbonate of potash will break down the curd that is beginning to form, in consequence of souring.