That was used by Treets an English confection from the 1960's
The slogan "Melts in your mouth, not in your hand" was used for M&M's to emphasize their chocolate shell coating that prevented them from melting in your hand. This slogan aimed to highlight the durability of M&M's and differentiate them from other chocolate candies.
"Melts in your mouth, not in your hand" -M&Ms
It melts in your mouth not in your hand. M&M
The "Melts in Your Mouth, Not in Your Hand" slogan for M&M's began in 1954.
Interestingly in the UK that slogan ("Melts in the mouth not the hand") was applied to milk chocolate Minstrels - they were a large globule of chocolate covered in a sugary coating that had a melting point higher than 36oC (normal body temperature) and so didn't melt, whereas chocolate as a melting point a little under 36oC and so does melt, in the hand. I presume the m and m slogan is for a similar reason.
m&m's
it melts in your hand because your hand has heat causing the chocolate to melt.
melt in your mouth not in your hand.
wen we put choclate in our pocket it turns soft as the temperature is more in our pocket than in refrigerator.........
The scientists working at Mars candy company under a contract from the US Army during World War II. During the African campaign the chocolate candy bars soldiers carried in their packs kept melting so the Army contracted with Mars candy to develop a way to keep chocolate bars form melting. The original slogan was supposed to be "melts in your mouth, not in your pack". But they didn't figure it out until the war was almost over. They still liked the result so they sold it as "melts in your mouth, not in your hand".
A unique selling proposition, is important in competitive markets. Some of the propositions from competitors in the chocolate industry, including M&M's with "The milk chocolate melts in your mouth, not in you hand," stick in your mind. Mast Brothers Chocolate is handcrafted and each block is made and wrapped individually.
1954 ~ see related link below .