@dlowan,
It was as noted before, (contrary to Farmer Lad's belief) sour. Remember when nuking your sour cream that it will turn into a strange substance and needs to be reunited with the beet juice to make it acceptable again.
On one occasion, the Pontifex family was out of sour cream and tried using heavy cream when they had dinner guests, It didn't go well and they were forced into exile in Erewhon. Oddly years later a new fangled item came to be
Erewhon brown rice cream.
That old Sammy Butler was ahead of his time...
