PT  - JOURNAL ARTICLE
AU  - A. A. Gardea
AU  - P. B. Lombard
AU  - C. H. Crisosto
AU  - L. W. Moore
AU  - L. H. Fuchigami
AU  - L. V. Gusta
TI  - Evaluation of Frostgard as an Antifreeze, Inhibitor of Ice Nucleators, and Cryoprotectant on Pinot noir Leaf Tissue
AID  - 10.5344/ajev.1993.44.2.232
DP  - 1993 Jan 01
TA  - American Journal of Enology and Viticulture
PG  - 232--235
VI  - 44
IP  - 2
4099  - http://www.ajevonline.org/content/44/2/232.short
4100  - http://www.ajevonline.org/content/44/2/232.full
SO  - Am J Enol Vitic.1993 Jan 01; 44
AB  - Laboratory procedures were developed to determine the effectiveness of Frostgard (FG). Specific experiments tested its antifreeze, anti-ice nucleation, and cryoprotection properties in grapes. The freezing point of water was related to the amount of impurities in the water and less with FG concentration. FG at 1% (v/v) depressed the ice nucleation temperature (INT) of water solutions by 1°C. Also, FG depressed INT of ice nucleation active (INA) bacterial suspensions in addition to kill the bacteria. The anti-ice nucleation properties were also tested on fluorophlogopite, an inorganic ice nucleator. FG required the presence of ice nucleators to effectively depress INT, possibly by binding to active nucleation sites. FG at 0.25% (v/v) reduced the freezing injury to grape leaf disks by 21% to 25% at -2°C. At lower temperatures there was no protection. Our results suggest that the practical significance of the cryoprotectant nature of FG is very limited.