Cryoprotectants are compounds used to protect frozen foods from quality deterioration during freezing and frozen storage. They include sucrose, which prevents muscle protein denaturation during the frozen storage of surimi, and sorbitol, starch or starch hydrolysates, which restrict undesirable changes in the functional properties of meat proteins. Glycerol is also commonly used as a cryoprotectant. These substances stabilize proteins against freeze damage, slow the growth of large ice crystals that would rupture tissue, and reduce drip loss on thawing. They are essential in frozen fish, meat and dough systems, and the same compounds protect starter cultures and enzymes during laboratory cryopreservation.