Processing Details

Processing

    Processing of California raisins involves a multi-faceted process, including inspection by the USDA to ensure the raisins meet federal standards. Part of the crop is selected to make raisin juice and raisin paste for commercial applications. Before raisins are unloaded, government inspectors gather samples from the middle of each box to make sure they are free of imperfections. Then they’re “processed”, size-graded, washed in pure water and moved through a laser sorter to remove any unwanted material.
    After final inspections, raisins are automatically weighed and packed in a variety of convenient sizes and shipped around North America and the world.

    Part of the crop is used to make raisin juice (a minimum of 70 percent natural fruit soluble solids) and raisin paste (made from 100 percent raisins), which are added to a variety of foods, including dairy, confectionery and bakery items.

    The production and manufacturing of California Raisins for consumption is a fascinating process. Understanding all the aspects of raisins, the products made from them, benefits of their use, and the differences as they are manufactured – all that information resides in the technical brochure.

    Storage

    Temperature

    California Raisins may be stored at room temperature without noticeable loss of color or flavor for a few months. The stability at room temperature will be dependent upon the moisture levels of the raisins and the relative humidity of the atmosphere. If the storage room temperature exceeds 10ºC (50ºF), the relative humidity should be kept below 55%. Raisins should be stored away from grain products such as wheat flour and corn meal. If the storage room temperature and relative humidity are high, refrigerated storage may be adopted for short periods of time.

    Relative Humidity

    The optimal relative humidity for storage of raisins is in the 45-55% range. Raisins then neither gain nor lose moisture. Controlling the relative humidity is particularly critical if the storage temperature is not optimal. Lower temperatures slow the moisture transfer rate from the air to the raisins. Poly-bags and proper packaging help to protect raisins in high humidity conditions.

    Purchasing Specifics

    • Parent Grape: Seedless
    • Description: Naturally sun-dried.
    • Approximately 2000-2400 berries/kg (1000-1200 berries/lb.)
    • Packaging: Available in 12.5 kg cases, 11.3, 13.6 and 18.1 kg containers (25, 30 and 40 lbs.)
    • Availability: Excellent supply year-round.

    California Raisin Storage & Handling Tips

    • Controlled, cool storage is the best way to keep raisins. Raisins will retain their color, flavor and nutritional value for up to five months if stored at 45° F or less.
    • To maintain optimum freshness, keep raisins sealed in an airtight container in the refrigerator or in your coolest storage area.
    • Raisins freeze well for long periods of time. They also thaw quickly at room temperature for a quick, convenient and healthy snack.
    • When raisins become dry or when a recipe calls for plumped raisins, cover the amount needed with very hot tap water and soak for 2 to 5 minutes. (Do not soak any longer than five minutes. Flavor and important nutrients can be lost.)
    • When chopping raisins, always use a lightly oiled knife or blade.

    Quality Assurance

    The Finest From California

    It’s August in the San Joaquin Valley. Another bountiful season is coming to a close. Trucks are taking loads of raisins from the farmers’ yards to the packing plants – a mark of the season’s end.

    Before raisins are unloaded from their bins, government inspectors take long prods to gather samples from the middle of each box. United States Department of Agriculture (USDA) standards must be met to ensure that each box is free of imperfections. Next, raisins are processed, which means they go through a series of conveyor belts and drums to remove remaining stems, chaff or lightweight fruit. The raisins also are sent through a vacuum air stream to catch any other undesirable materials. Finally, they’re size-graded and thoroughly washed in pure water. In preparation for packaging, the raisins are moved through a laser sorter. The sorter’s light beams, along with a computer, see if anything besides raisins is passing through the stream. If material other than a raisin is present, the computer sends a burst of air to knock it out of the stream of raisins and down a trough. California raisins are inspected under the most rigid standards. Quality control technicians inspect the raisins by hand throughout the packing process, thus assuring that California raisins are the cleanest, highest quality in the world. After final inspections, raisins are automatically weighed and packed in a variety of convenient sizes. California raisins are then shipped around North America and the world for consumers to enjoy.

    Question & Answer

    Q. How many raisins to lb/kg?
    A. 1000-2000 raisins/lb (2,000-2,400/kg)

    Q. Package sizes?
    A. 25, 27.5 and 30 lb containers (11.3, 12.5 and 13.6 kg)
    Other package sizes are available, contact a packer

    Q. Water activity of raisins?
    A. At 25° C, water activity is 0.51-0.56 at 13-15% moisture and 0.55-0.62 at 15-18% moisture.