Research Accomplishment Reports 2010

S1033: Control of Food-Borne Pathogens in Pre- and Post-Harvest Environments

M.C. Newman
Department of Animal and Food Sciences

 

Non-Technical Summary

The Centers for Disease Control and Prevention (CDC, 1999) reported new, more accurate estimates of foodborne illnesses that occur annually. An estimated 76 million cases of foodborne illness, 325,000 hospitalizations, and 5,000 deaths occur each year from food-borne microorganisms (Mead et al., 1999). The food safety surveillance system, FoodNet, indicates that more cases of food-borne illness occurred, but fewer deaths were caused by foodborne disease agents than previously reported. Campylobacter spp. was responsible for the most cases of foodborne illness. Salmonella (nontyphoidal) caused the most deaths; Listeria monocytogenes also causing a significant number of deaths. In summary, the report indicates that foodborne pathogens have a significant impact on human health and the food industry in the United States.

In addition to human suffering, foodborne illnesses also have a substantial economic impact in the United States. The annual cost of foodborne illness in the U.S. is estimated at $5-$6 billion for loss of productivity and medical expenses (Marks and Roberts, 1993). The most costly food-borne illnesses are caused by Toxoplasma gondii, Salmonella spp., Campylobacter spp., and enterohemorrhagic Escherichia coli. New methods to prevent, reduce or eliminate foodborne disease agents at all points of the food chain, from farm to fork , are needed to improve the safety of the food supply to prevent illnesses and deaths and to prevent economic losses to the food industry.

2010 Project Description

Milk has been identified as a high risk food due to numerous reasons including bulk collection and holding, transportation systems, target consumer populations. Heat treatments applied to each food product shall vary with product and range up to heat treatments used in the commercial food processing industry. Processed cheese currently is processed at temperatures ranging from pasteurization to practical commercial sterilization. Milk processing varies in actual pasteurization treatments (generally exceeds regulatory requirements) to ESL and UHT.

Compounds identified as effective in the previous studies, have been coupled with heat treatment to antimicrobial activity using a combination of four holding times at four temperatures. Heat treatments were monitored with a temperature profiling system to compare relative lethality's of each treatment. Effectiveness was determined by enumerating survivors on appropriate recovery media. Milk and processed cheese products held at refrigeration temperature for times approaching normal commercial shelf life of the products. Vegetative pathogens were evaluated similarly in milk and ground beef using stationary phase cells and appropriately lower sub-lethal heat treatments. Heat treatments utilized are intended to have no effect on the normal organoleptic properties of the food product.

2010 Impact

Antimicrobial effect of the spices and herbs in combination were achieved throughout the study and was related to the synergistic effects of the spices and herbs in foods.

2010 Publications

Derrick L. Hammons, A S. Kaan Kurtural, M. C. Newman, and D. A. Potter. 2009. Invasive Japanese beetles facilitate aggregation and injury by a native scarab pest of ripening fruits. Proc Natl Acad Sci. 106(10)3686-3691.