The margarine test: why marketers must look at what people do rather than what they say

The 1940s were a dispiriting decade for American margarine makers.
Despite being cheaper than other spreads, shoppers viewed margarine as an unappetising white gloop. Its reputation was so tarnished that Joseph Quarles, a Wisconsin senator, said: "I want butter that has the natural aroma of life and health. I decline to accept as a substitute caul fat, matured under the chill of death, blended with vegetable oils and flavoured by chemical tricks."
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