Coolin

This biotechnological blend combines a yeast ferment with an edible mushroom extract and moisturising glycols. The mushroom extract contains grifolin derivatives that can influence a receptor sensitive to heat and capsaicin. The ingredient is intended for products that provide a soothing, cooling sensation without menthol.

Coolin blocks or reduces activation of the TRPV1 receptor, which is involved in the perception of burning, heat, itching and sensitivity. This may help skin better tolerate heat stress and cosmetic stimuli. The ferment and glycols also help hydrate the skin. The effect is not anaesthetic and is not intended to mask irritation caused by an overly harsh formulation.

We recommend it for sensitive, reactive, redness-prone and heat-stressed skin. It is suitable for after-sun and after-shave products, or for skin that does not tolerate menthol well. For rosacea, the formulation must be free from fragrance and strong acids. If you have mushroom allergies, a patch test is advisable.

A controlled study involving 17 participants showed that 14 days of using a 3 per cent Albatrellus ovinus extract increased the heat pain threshold by 1,5 degrees Celsius compared with baseline and placebo. The treated skin also maintained its tolerance better after irritation with capsaicin (International Journal of Cosmetic Science, 2017). The blend uses a related mushroom extract, so the supplier's technical data must be followed.

The recommended concentration is usually around 1 to 3 per cent. The ingredient is added during the cool-down phase at a mild pH. It combines well with panthenol, betaine and barrier lipids. The preservative system must be compatible with the ferment and validated by a challenge test.

The soothing effect is best achieved with a simple routine, without excessive fragrance, essential oils or layering several acids at once. If your skin is reactive, it is advisable to try a new product on a small area first. Persistent burning, pronounced flaking or worsening redness are not signs of normal adjustment and are reasons to stop using the product and consult a dermatologist. Consistent daily sun protection is also important.