I don't remember it but I'm of an age when I should. Anyway, I found this online: Whip ’n Chill: One of the most popular desserts of the sixties, Whip ’n Chill was a strange one, similar in texture and taste to mousse, but with a faint tang of chemical design. Its ingredient list reads like a toxic waste dump posting: propylene glycol monostearate, sodium casienate, acetylated monoglycerides, cellulose gum, hydroxylated lecithin, sodium silico aluminate and sodium stearoyl-2- lactylate. During the sixties, the artificiality of Whip ’n Chill had a novelty appeal. People still believed in the space age, and Dow Chemical Company’s motto was “Better Living Through Chemistry.” With the end of the space-age, Whip ’n Chill’s novelty was replaced with horror when people began to realize just what they had been eating.
It doesn't sound too appetizing to me, but I searched and found that the Vermont Country Store carries (or carried?) it. They show it in their catalog but said it's unavailable right now so maybe it's just out of stock?