Does keeping the gel in the fridge make a difference, and is the 50 ml size allowed in hand luggage?

Yes, refrigeration is worth trying. The gel texture already gives an immediate cooling sensation on contact, and storing the tube in the fridge makes that effect noticeably stronger. Applied cold, it can feel especially pleasant on shoulders, the back of the neck or legs after a long day outdoors or at the beach. Chilling is purely about comfort — it does not change what the product does, and the gel keeps its texture at fridge temperature. Just avoid the opposite extreme: do not leave it in a hot car or in direct sunlight, as heat can degrade cosmetic formulas over time.

As for travel: the 50 ml size is under the standard 100 ml limit for liquids and gels in carry-on baggage under EU aviation rules, so it can go in your hand luggage inside the usual transparent resealable bag. That makes it easy to have on hand right after landing in a warm destination, rather than packed away in checked baggage. The compact size also fits a beach bag or gym bag without taking up much room, which matters if you plan to reapply during the day rather than only in the evening.