Summer humidity presents numerous cold storage concerns
Monday, Jul 29th 2013

Although food storage facilities primarily are worried about rising temperatures damaging produce, humidity can be just as damaging. In particular, cold storage facilities that do not have quality humidity monitoring equipment in place are susceptible to a wide variety of plant diseases and other external concerns.

In particular, one of the biggest threats emerging in certain parts of the United States this year are spider mites. In a recent Springfield News-Reader article, Lala Kumar, a horticulturist with the University of Missouri Extension, noted that the two-spotted spider mite has been especially prevalent this year in Missouri, damaging green beans, tomatoes, eggplants, cucumbers and other agricultural products.

In contrast to other pests like bacteria and fungi that prefer moist conditions, spider mites thrive when it is hot and dry out, Kumar noted. The peak time for spider mites is from June through August, when the pests reproduce in as little as 10 days.

Spider mites are far from the only concerns produce handlers have during the summer, as many other issues are exacerbated during the warmer months of the year. Other issues, according to Sault This Week, include:

  • Black Knot
  • Powdery Mildew
  • Leaf Blight
  • Clematis Wilt
  • Black Spot
  • Fire Blight

Not only do cold storage facilities need to be extra vigilant about its produce supplies during the summer, but the building itself can be prone to damage. CBS affiliate WRBL noted that when moisture levels rise in conjunction with temperature, facilities can be especially prone to mold.

Best practices for safe summer food handling
Although the number of summer-related produce storage concerns are vast, facilities managers can use humidity and temperature monitoring equipment to protect stores. The key to ensuring pests, mold and other issues are not abundant, according to The Ohio State University, is to carefully consider the food item in question and what threats are most prevalent.

Facilities managers may want to first take into account the concern most commonplace at the moment. For example, Kumar noted the prevalence of spider mites in Missouri, so cold storage facility managers in that area may want to keep leafy vegetables more moist to prevent its spread. However, Sault This Week reported that other pests like Black Knot and Fire Blight affect other parts of the plant and can even thrive under the same conditions that kill spider mites.

In addition, cold storage locations must also keep in mind the environmental conditions best suited for the fruit or vegetable in question. After all, a warehouse that is too dry for spider mites could also be too dry for the produce inside. For instance, while a relative humidity between 95 percent and 100 percent are ideal for Brussels sprouts, leafy greens and sweet corn, this would be too moist for onions and garlic, as those plants prefer a relative humidity between 65 and 75 percent.

Temperature is critical in this regard as well, as the ideal range for one vegetable may be totally wrong for another one. For example, jicama, sweet potatoes and watermelon do best at warmer temperatures, between 65 degrees and 70 degrees Fahrenheit, according to The Ohio State University. In contrast, mushrooms, peaches, coconuts and most other fruits and vegetables should be stored at cooler temperatures, between 32 degrees and 36 degrees F. These are far from the only two ideal temperature ranges as well, as other fruits and vegetables need to be stored at anywhere between 40 and 60 degrees in addition to the previous two temperature ranges.

Although the ideal temperature and relative humidity varies considerably depending on the fruit or vegetable in question and the top pest-related concern, the benefits provided to cold storage facilities managers by temperature and humidity monitoring equipment is still vast. No matter the threat in question, environment monitoring systems can help keep produce fresh.