Name: ken e anderson
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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Update: June 2012