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Can you grind peanuts without releasing oil? Curious about how plants store oil

  1. Sep 5, 2012 #1
    I know that some peanut doesn't have oil separation, but this is due to emulsifier chemicals that are added. I'm wondering what causes the oil to be released. I assume the storage structure is ruptured, and the oil molecules are consequently released.

    What exactly is a peanut? It's not a single cell, is it? And what sort of structure would hold the oils in?

    Would it be possible to grind it to a powder without any sort of oil release? What would make it possible to do so with other seeds?
  2. jcsd
  3. Sep 5, 2012 #2


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  4. Sep 5, 2012 #3
  5. Sep 5, 2012 #4


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    And no, you cannot grind peanuts without releasing oil. My wife buys fresh-ground peanut butter (no salt or added oils) from the local health-food store so that I can coat pills with it to get Duke to take his pills. That peanut butter actually has to be mixed to stir the oils back in. Duke loves it. It's just ground peanuts - nothing else.
  6. Sep 5, 2012 #5
    Heheh yes, my dog also loves his peanut butter.

    As far as grinding goes, I don't think it's impossible. I put chopped peanuts on my pad thai and there is no oil release. Could I not just chop them 10x as finely? 100x?

    I scanned through the PDF. It looks at the effects of oil cooking and oven cooking (both at 160 °C) on protein bodies, cell junctions, and the cytoplasmic network. It seems like in all cases, these structures are broken down, and more heating = more break down. Heating in oil caused a greater rate of break down (this makes sense because of the greater heat capacity of oil vs. oven air).

    They didn't talk about fat storage. Breakdown of all of the bodies they examined would probably release oils. If you're chopping peanuts, you're physically breaking these cellular structures at least a little bit. I still don't know the limit of how finely you could chop without significant oil release, though.

    My guess is that the amount of oil released is roughly proportionate to the surface area of the "chopped particles", so 100x more fineness of chopping would result in perhaps 1.5^100 the amount of surface area (the surface area increase would depend on geometry, but I'm thinking chopping a particle in half might increase surface area for that mass by a factor of 1.5).
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