On food and cooking the science and lore of the kitchen ( PDFDrive ) 105

butsmoothliquid.“Bulgarianbuttermilk”isa
versionofculturedbuttermilkinwhichthe
creamculturesaresupplementedorreplaced
byyogurtcultures,andfermentedatahigher
temperaturetoahigheracidity.It’snoticeably
moretartandgelatinous,withtheapple-like
sharpnesstypicalofyogurt.
RopyScandinavianMilks
A distinctive subfamily among the cream
cultures are the “ropy” milks of
Scandinavia, so-called because they’re
more than stringy: lift a spoonful of
F i n n i s hviili,
Swedishlångfil, or
Norwegiantättemjölk, and the rest of the
bowl follows it into the air. Some ropy
milksaresocohesivethatthey’recutwith
a knife. This consistency is created by
particularstrainsofcreamculturebacteria
that produce long strands of starch-like
carbohydrate. The stretchy carbohydrate
absorbs water and sticks to casein


particles, so manufacturers are using ropy
strains ofStreptococcus salivarius as
natural stabilizers of yogurt and other
culturedproducts.
Cookingwith
FermentedMilks

Mostculturedmilkproductsareespecially
susceptibletocurdlingwhenmadeintosauces
oraddedtootherhotfoods.Freshmilkand
creamarerelativelystable,buttheextended
heattreatmentandhighaciditycharacteristic
ofculturedproductshavealreadycaused
someproteincoagulation.Anythingthecook
doestopushthiscoagulationfurtherwill
causetheproteinnetworktoshrinkand
squeezeoutsomeofthewheyandproduce
distinctwhiteparticles—proteincurds—
floatinginthethinnedliquid.Heat,salt,
additionalacid,andvigorousstirringcanall
causecurdling.Thekeytomaintaininga