Thermolabile Vitamins

Vitamins

Vitamins are essential molecules for human life; they can be classified according to different criteria; among the most known we remember:

solubility:

In water (water-soluble vitamins)
In lipids (liposoluble vitamins)

and heat stability:

Heat resistant (thermostable vitamins)
Not resistant or partially resistant to heat (thermolabile vitamins)

What are they?

The group of thermolabile vitamins is represented essentially by ascorbic acid (vitamin C) and by numerous vitamins of group B; in particular:

Thiamine (vitamin B1)
Riboflavin (vitamin B2)
Pantothenic acid (vitamin B5)
Folic acid (vitamin B9)
Ascorbic acid (vitamin C)
Retinol (or vitamin A) and beta-carotene (precursor of vitamin A)
Tocopherol (vitamin E)

While the thermostables are all the others.

How to preserve them

In order to guarantee the right intake of vitamins in the diet, in addition to ensuring that at least the minimum recommended intake with food is introduced, it is essential to examine the entire dietary style to ensure that the efficiency of thermolabile vitamins is not completely compromised.

Folic acid

Assessing the efficiency or otherwise of thermolabile vitamins may seem overly zealous, but it is not. A perfectly fitting example concerns folic acid, otherwise called vitamin B9; folic acid is an essential molecule for the synthesis of nucleic acids and its deficiency can significantly affect the efficiency of erythrocytes, causing pernicious or megaloblastic anemia. Unfortunately, the most important side effect of vitamin B9 deficiency concerns the eventual fruit of conception; the pregnant woman who defects in folic acid can cause irreversible neural damage to the unborn child. For hygienic reasons, the pregnant woman SHOULD limit the amount of raw food, therefore, in order to prevent vitamin deficiency, usually specialists administer some food supplements ... but it is not enough to integrate only during pregnancy, it is appropriate to guarantee supply of folic acid even before conception! In this regard, the advice of all nutrition professionals is to increase the intake of vitamin B9 through the frequent and systematic consumption of CRUDE green leafy vegetables. Unfortunately, it often happens that the subjects "refractory to the salad" orient themselves more towards the cooked side dishes; unfortunately, in this case the inactivation of folic acid as a thermolabile vitamin is quite relevant. It is therefore advisable to consume AT LEAST a portion of raw vegetables and a couple of portions of fresh fruit (in this case oranges) per day.

Other Vitamins and Industrial Products

The same is true for all thermolabile vitamins and the severity of the risk of hypovitaminosis is directly proportional to:

Personal need
Quality of the selected foods (presence or absence of thermolabile vitamins)
Consumption method (consumption of raw or cooked foods)

To be precise, the stability or otherwise of thermolabile vitamins is a major obstacle for home consumers compared to industries. In the large-scale retail trade, food technology has achieved excellent goals and several experimental works (the most famous of which relate to tomato processing) have documented the preservation of thermolabile vitamins, which sometimes exceeds 90% abundantly. Not all, in some cases (which have nothing to do with thermolabile vitamins), the thermal treatment FAVORES the nutritional enrichment of the finished products by activating different antioxidant molecules (Maillard reaction in the cooking of the tomato) or denaturing some binding proteins (avidin protein contained in the egg white).

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