Liquid nitrogen has long been used in molecular gastronomy demonstrations and the instantaneous vapor cloud that results from the condensation of ambient air is very impressive.
However, besides its “wow” effect, there’s another reason for this technique’s enduring popularity. Due to its ability to quickly cool preparations, liquid nitrogen significantly outperforms the classic freezing process. Freezing at -4°F (-20°C) causes water to form into increasingly larger crystals and alters the product’s initial structure. Frozen products thus lose a lot of their water and soften. The radical change in temperature brought about by nitrogen ensures the formation of much smaller ice crystals that leave the product’s cell structure intact.