Ingredienserna till svensk gräddfil är väl pastöriserad grädde och syrningskultur.
I nordamerikansk sour cream kan de ha många olika tillsatser inte så konstigt om det smakar olika. Räcker det inte att det är olika syrningskulturer för att smaken ska bli olika?
Citat:
Commercially produced sour cream contains no less than 18% milkfat before bulking agents are added, and no less than 14.4% milkfat in the finished product. Additionally, it must have a total acidity of no less than 0.5%.[4] It may also contain milk and whey solids, buttermilk, starch in an amount not exceeding one per cent, salt, and rennet derived from aqueous extracts from the fourth stomach of calves, kids or lambs, in an amount consistent with good manufacturing practice.[2] In addition, according to the Canadian food regulations, the emulsifying, gelling, stabilizing and thickening agents in sour cream are algin, carob bean gum (locust bean gum), carrageenan, gelatin, guar gum, pectin, or propylene glycol alginate or any combination thereof in an amount not exceeding 0.5 per cent,[2] monoglycerides, mono- and diglycerides, or any combination thereof, in an amount not exceeding 0.3 per cent, and sodium phosphate dibasic in an amount not exceeding 0.05 per cent.
https://en.wikipedia.org/wiki/Sour_cream#Commercial_varieties