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Name: ken e anderson
Status: N/A
Age: N/A
Location: N/A
Country: N/A
Date: 1999 

I used to churn butter when I was on the farm. Why or how does butter form when cream it is stirred or churned?

Milk is an emulsion. Emulsion are a mixture of at least two normally non-mixable (immiscable wrong spelling!). Many people enjoy peanut butter which is a mixture of peanut oil and peanut water soluble compounds. Homemade peanut butter will separate into two layers that need to be peroiodically remixed. Store bought has special emulsifiers to prevent this annoying occurance. If milk was not an emulsion, the mother would have to suppley two different kinds of milk. One would be fat and fat soluble, the other water soluble (protein and carbohydrates). The churning process forces water and other non-fat molecules out of the fat (butter) so that the emulsion is broken and the fat congeals and the non-fat components separate. I cannot explain the physio-chemistry behind this but I HOPE SOME one out there can. Help!

michael b lomonaco

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