[Practical QA Solutions] Temperature Modification

Manipulating an environment with temperature has been recognized as an effective method for managing insect activity. Using temperature is a long-term approach within the Integrated Pest Management toolbox, and using cool environments may just be a tip of the iceberg for storing and shipping food products. A practical and often overlooked solution for food protection is temperature modification, on the cool side. As we continue to lose traditional pest control tools, we will see the wisdom of this pest management tactic evolve into other areas.

Modifying an environment using high temperature for destroying insect life has long been recognized as a practical and effective method of protection. As far back as the turn of the 20th century, producers were using heat to control pests. An excellent up-to-date reference on this subject is Insect Management for Food Storage and Processing; second edition, edited by Jerry Heaps and specifically Chapter 10, “Temperature Modification for Insect Control” authored by myself and three other experts.

Why don’t we see more food products shipped and stored at cool temperatures? A practical and often overlooked solution for food protection is temperature modification, on the cool side. As we continue to lose traditional pest control tools, we will see the wisdom of this pest management tactic evolve into other areas.

INSECT REPELLENT. One benefit of cooler temperature is the repelling action it provides as insects search for their ideal temperature. In the case of stored product insects, the optimum range is 75 degrees to 90 degrees Fahrenheit. From a stored product insect perspective, research (P. G. Fields,1992) has shown that insect development slows in the 65- to 70-degree range and stops in the 55- to 60-degree range.

BENEFITS FOR FOOD. How does manipulating an environment to less than 60 degrees benefit our food? If food products are shipped and stored in a cool environment, insect development and subsequent damage would stop. As insects search for optimal temperature and discover a cool environment those insects would leave that area and no young (eggs) or other contamination would be left behind.

For example, if cool environments were used to store birdseed a chronic retail insect problem could be avoided. Insect eggs would not hatch and insect metamorphosis would cease. And, benefits of cool environments would extend to the birdseed-neighboring food products within various distribution and retail centers.

Much infestation originates in the transportation sector as food is delivered from manufacturer to distributor to retailer. Refrigerated trailers are under utilized in the distribution world. Food protection would be elevated if more food products were handled in a cool environment throughout distribution and transportation. Insect-sensitive products such as birdseed, dry pet food and flour would be prime candidates for this cool approach, thereby reducing infestation damage and related costs in the distribution cycle toward retail.

EXTENDING SHELF LIFE. A hidden benefit of storing and shipping food at cool temperatures is its shelf life. High temperatures found inside trailers — especially during summer months — are tremendous shelf life stressors.

Brief periods at high temperature can be tolerated by some products (cocoa beans) but not others (chocolate). Recorders have shown temperatures can reach in the mid-100 degree range. Extended time periods at these temperatures can reduce shelf life and create substandard product. Grocery centers using trailers as warehouse extenders create various problems and stresses product shelf life.

CONCLUSION. Manipulating an environment with temperature has been recognized as an effective method for managing insect activity. Using temperature is a long-term approach within the Integrated Pest Management toolbox, and using cool environments may just be a tip of the iceberg for storing and shipping food products.

The author has spent more than 30 years in food quality assurance. He is a Certified Professional Instructor and can be reached through www.qualitycenteredconsulting.com or by calling 816/436-1627.

Auditor's Soapbox:
There are those that say temperature modification for insect management is not cost effective. These tend to be the same people who do not measure a return on investment. They do not track the total cost of product damage through distribution to retail. The total cost of damage for infestation, shelf life or just reputation protection is always higher than actual replacement cost. Product damage can be a means to profitability. If you measure it, you can manage it and then justify solutions.