- Stockpiling Guidelines for Crop Quality
- Almond Board Partners with Food Network Host Ellie Krieger
- Reaching Out to French-Canadian Dietitians
- The Growth Advantage
- Sustainably Speaking — Sustainably Program — Pointless Paperwork or Production and Marketing Tool?
- Almonds a Hit at IFT
- Leadership Program Continues on Path to Success
- California Almonds Part of Nutritional Well-Being in Asia
- Food Quality and Safety Symposium Success
Stockpiling Guidelines for Crop Quality
Determining the best management techniques for almond harvest and stockpiles has been the subject of several years’ research supported by the Almond Board of California. Currently, research is focused on stockpiling and crop moisture content to avoid mold growth in piles, particularly the Aspergillus fungus that produces aflatoxin.
Crop moisture should be determined while the nuts are on the orchard floor to avoid excess moisture in the stockpile.
Research shows that stockpiling in-hull almonds at a moisture content greater than 7% leads to a relative humidity (rH) within the stockpile of more than 70%, which is the maximum allowable rH for almond storage. Molds such as Aspergillus are more likely to grow in the outer portions than in the rest of a high-moisture content pile. Researchers suggest that almonds should not be stockpiled if either the hull moisture content exceeds 13%, or the kernel moisture content exceeds 6%.
Crop moisture should be determined while the crop is on the orchard floor, either before or after sweeping. In either case, be sure that you take a representative sample across the orchard floor or from the top and bottom of windrows. Several factors affect condensation, mold growth and aflatoxin production in the stockpile:
Orientation and shape. Orienting the long axis of piles in a north-to-south direction is preferable. Smoothing the tops of piles helps to minimize the concentration of moisture from condensation and resulting mold growth.
Tarp type and color. White-on-black tarps are best for minimizing temperature fluctuations and resulting condensation. Almonds covered with white-on-black tarps were up to 40 degrees cooler than nuts under clear tarps, which had the highest potential for condensation and mold growth. White tarps are intermediate, in terms of temperature ranges and condensation, between black-on-white and clear.
Air circulation. If piles are stacked with a higher-than recommended percentage of moisture, it is important to open them up in the daytime, when the rH is lower, and close them at night, when the rH is high.
Three years of research reports on almond stockpiling and aflatoxin by UC Davis Extension specialist Bruce Lampinen and Themis Michailides (plant pathologist, UC Kearney Agricultural Center) are available at the Almond Board website. Go to AlmondBoard.com/ResearchReports, choose Annual Research Reports, Proceedings and Posters, then Aflatoxin Field Research.
Tweet
