It’s raisin drying time in California’s central San Joaquin Valley. We used to grow Thompson Seedless grapes for raisins until the prices dropped too low. Mike called Sun-Maid, the company that bought our raisins, and asked what to do. The grower’s consultant asked how old the vines were. Mike told him they were 15 years old, then he said, “I just answered my own question.” Mike pulled out the vines and planted peaches. Fifteen years is a good production life for Thompson Seedless grape vines. That was about 20 years ago. Today raisin prices are soaring and raisin growers are smiling.
These photos were all taken on the same day (September 11, 2012) at three different farms within 2 miles of each other. This process will continue until approximately September 20th. Why September 20th? Because, for farmers that have insurance, that is the last date to set down grapes in order to be covered in case of rain or other natural disaster.
How Raisins are Made
To make raisins, first the grapes are tested for sugar content. A brix between 18 and 21 is considered good, but 23 is ideal. Then, the grapes are picked by hand and placed on paper trays to dry. In normal years, there are two trays of grapes per vine. The first photo shows a light crop. Some fields were hit with a late frost, so the delicate blossoms were damaged. Picking grapes is hard, dirty work. There are spiders and insects that take up residence in the vines. The temperatures are sometimes in the 100s during harvest. Pickers use special knives to cut the clusters of grapes from the vines and then lay them on the trays. There are approximately 15 pounds of raisins per tray.
Just an 1/8 mile away in another vineyard the grapes were already drying on their trays. These grapes were probably picked a week earlier. It takes two to three weeks for the grapes to dry completely, depending upon the weather.
Notice how the ground slants a bit. There is a special piece of machinery that is pulled by a tractor and flattens the ground between the rows. This allows for better exposure to the sun and also provides runoff if it rains during drying. I remember the days of watching the weather forecast for rain this time of year. If it should rain before the trays are rolled, the growers have few choices. It depends on how dry the raisins are and the cost/benefit ratio of trying to save them versus taking a loss or collecting insurance.
One of my favorite memories of our younger years in farming was going out one night during a full moon and rolling raisin trays because it was supposed to rain the next day. My husband was working without a shirt and I remember his back glistening with sweat as he bent over to roll the trays. It was actually kind of romantic working side-by-side. As long as you don’t mind getting dirt in places you never thought you could. But back to the raisins.
After the raisins are dry to a point, they are rolled in a loose trifold. This allow for air to continue the drying process while not over-drying them. The raisins can sit in the field longer since they are covered by the tray that protects them as they dry.
Notice how the rolled trays are placed at the top of the slope and near the vines. This further protects them should it rain. Once the raisins have dried completely, the trays are picked up and dumped into raisin bins (see photo below taken later) that hold about 1,000 pounds of raisins. The grower makes an appointment with the processor and delivers the bins to the processing plant.
Sun-Maid used to have tours of their plant. Now they just show a video to visitors. The tours stopped after 9/11 for security reasons. I remember it was very noisy inside the plant. There were miles of conveyor belts moving raisins and boxes hither and yon like the doors in Pixar’s Monster’s Inc. They showed us how they sugar-coated the raisins for Raisin Bran and made various raisin snacks.
My favorite raisin snacks are GORP (Good Old Raisins and Peanuts) and raisins and pecans. My grandma Carlson often made Applesauce Raisin Cake. What is your favorite snack or recipe that has raisins in it?