Several raisin growers have already laid their grapes out to dry so they welcome the sudden rise in temperatures. Once the grapes are placed on trays it takes about two weeks for them to dry.
University of California Viticulture Farm Advisor Stephen Vasquez said growers welcome the hotter than normal numbers. Vasquez said, "As hot as the temps can get they certainly appreciate that because it means they'll be able to dry their fruit without taking it to a dehydrator."
Most raisins are dried on trays. But Fowler grower Ed Nikssarian said a growing number of grapes are being dried on the vine. Nikssarian explained, "We're gonna cut these two buds out. They just get cut here and all this will dry up. The leaves and the grapes will start shriveling."
The heat increases the fruit's sugar content before harvest. Nikssarian uses a refractometer to see if his crop is ready. "You just lift it out and squeeze it on there, shut the lid and then look through it and it will tell you how much sugar's there. It is showing 17 sugar."
Nikssarian cuts his vines when he gets a 20 sugar reading. Temperature readings showed raisins on the ground get a much bigger dose of heat. Vasquez said, "Looks like about 144 degrees is what the ground temperature is."
The reading on the grapes drying on the vine was 99-degrees, which is why they need 5-6 weeks to dry. Vasquez said, "100 to 105 degrees is certainly welcome by raisin growers because in order to dry fruit like this, dried on the vine, it needs those high temperatures over a long period of time."