Dear all,
I was trying to understand how storage condition might affect tocopherols activity in that kind of oils that require a storage in freezing temperatures.
Does the low temperature, to some extent, slow down the oxygen scavenger activity of tocopherols and others antioxidants?
It happened that when I was opening the drums from the cooling room, the level of oxygen was still quite high (despite the nitrogen purging during the filling step ).
Do you think is that related to antioxidant activity deficiencies or rather might be related to the efficacy of the nitrogen purging step?
Any reference in this domain is more than welcome.
Thanks in advance for your feedbacks.
Also check https://www.hindawi.com/journals/jchem/2018/9375085/
Lowering the temperature even significantly slows the loss of antioxidant activity but does not eliminate it. Even at low temperatures, oxidation processes or enzymatic reactions take place. Of course, we can try to eliminate oxidation by storing food in a nitrogen atmosphere. But we cannot eliminate, but only slow down the enzymatic reactions by lowering the temperature.
Kindly check the following RG link:
Article Antioxidant Activity in Frozen Plant Foods: Effect of Cryopr...
In which it had been implied that the effect of freezing on the antioxidant activity of plant foods resulted in dependant on a series of intrinsic factors (e.g., composition and structure), while the role of extrinsic processing-related factors, such as freezing and storage temperatures, is still ambiguous. Many conflicting results are reported depending on the method of analysis used for the antioxidant activity evaluation and data expression (fresh or dry weight). Other intrinsic raw material properties such as cultivar, ripening degree, post-harvest conditions, as well as defrosting methods contribute to the aforementioned discrepancies.
One should also remember about the temporary increase in enzyme activity when freezing food containing water, which may additionally reduce the antioxidant activity.
Check: 10.1111/j.1365-2621.2009.02016.x
Encyclopedia of Human Nutrition (Second Edition), 2005