Assertion: baking powder's acid | /r/Causes | casein
Facets:
Source sentences:
text: These days, though, buttermilk is made from regular milk by dosing it with Streptococcus lactis, a bacteria that consumes lactose, the main sugar in milk, and produces lactic acid, which adds tartness to the buttermilk, as well as causing casein, the primary protein in milk, to curdle, thickening, or clabbering, the milk.