The most recent brand of sunflower butter (Mara Natha) that I've been using left a green tinted liquid inside the glass jar after I attempted to wash it out for recycling with water ~200°F/93°C and left the water in over night.
The liquid was not just floating oil on top, but a consistent transparent green, close to the darker green check of the cooking.se background.
I washed it out again, and the second time I just rinsed with warm tap water and left it again as an experiment this time, and it was a lightly tinged yellow color that one would expect/imagine would be left since that is close to the color of the oil that separates out before you mix it in.
Note, there is a bit of sea salt in the mixture of this one. Also, the sunflower seeds are listed as being roasted beforehand. This is not an organic product.
I thought, just maybe, I could have 'burned' the sunflower oil, so I checked around and found This page, that lists many different smoking points for the same oils and redundant and various stages of 'refinement.' However, the water was no longer boiling, and the lowest listed temp was 225°F/107°C on the various sources cited. I would think that a roasted sunflower seed would qualify as 'more refined' and therefore increase the smoking temperature of the oil crushed from it. Discussion of sunflower oil vs. peanut oil here.
What am I dealing with here?
Best Answer
Sunflower oil turns green in the presence of bases, such as baking soda. Most tap water in the US is alkaline with a pH value around 8, so that could also turn the sunflower oil green.