|MadSci Network: Biochemistry|
This is a complex question. Part of the issue is how modern margarines have been adapting to the need for non-trans fat products. They are often now blending different oils to accomplish what "hydrogenation" might have done originally. And working with a predominantly monounsaturated oil is probably easier than with oils with more higher degrees of unsaturation. So, in the end a lot depends on what the company actually does rather than a generalization by ingredient. What you would want is the fatty acid profile of the fat phase of the margarine -- the present of some monounsaturates and no trans fats would be ideal. (And the olive oil I believe also adds a nice flavor and gives it a "richer" marketing image.)
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