There has been a lot of talk about food safety and as you read in Charles Graham’s article in February, “New food safety regulations on the horizon,” several of the new regulations were discussed.
Food safety is a major concern for all industries and it may take only one outbreak to greatly affect the future of these industries. For the past few years, I have heard rumors that shellers are considering not buying pecans where livestock have been grazed under the trees as a means to reduce the risk of human pathogen contamination. These shellers are worried mainly about Salmonella and/or Escherichia coli (E. coli) contamination in pecans from manure of livestock. There are both harmless and harmful strains of E. coli. Harmless strains are typically part of the normal gut flora benefiting their host (humans or livestock), by producing biochemicals needed for normal growth and metabolism or preventing the establishment of pathogenic bacteria. However, E. coli O157:H7 is harmful and of great concern.
I agree there is a concern for grazing livestock and of the use of animal litter in orchards. However, I would like to point out that there are other concerns that should be addressed that may not be easily controlled by the grower.
This past year, in collaboration with Oklahoma State University, we started a study addressing “Does cattle grazing increase the food safety risks of native pecan?” We have taken a different approach in this study than what has been done before. We not only sampled cattle, pecans, soil and harvesting equipment, but we also sampled wildlife that were present in the pecan orchard. We sampled squirrels, crows, feral hogs and deer.
The preliminary results of this study indicated that wildlife has the potential to contaminate pecans. As we all know crows are a constant battle in the pecan orchard. Normally we are fighting crows trying to save as many pecans as we can. However, there is a bigger concern with crows. Of the crows sampled in this study over 53 percent tested positive for E. coli O157:H7 and 13 percent tested positive for Salmonella. Of the deer and hogs sampled, 40 percent tested positive for E. coli O157:H7 and Salmonella. Unfortunately, complete wildlife elimination is virtually impossible. In order to address these concerns, focus should be directed to sterilization practices once pecans are harvested.
The National Pecan Shellers Association has already taken precautions by setting standards for sterilization. However, a major concern for the pecan industry is the small crackers that do not take precautions. While cattle grazing may be eliminated or lessened in the orchard, it is critical to take note of the wildlife impact on pecan safety.