<OL> <LI> Obtain an accurate picture of current apple cider processing practices, including levels and types of microbial contamination, current manufacturing practices, and hazard analysis critical control point (HACCP) implementation; <LI> Determine the efficacy of sanitizer washes in reducing E. coli and other bacterial and fungal pathogens on apple surfaces; <LI> Evaluate the effectiveness of electron beam irradiation in reducing the levels of pathogenic and spoilage microorganisms in cider, and the effect of irradiation on quality attributes of apple cider; <LI> Provide relevant information on good manufacturing practices and HACCP implementation to cider producers, general information on fresh fruit and cider quality and safety to consumers, and in-depth information and practical experience in food safety programs to future food industry professionals.
Economic pressures from intensifying competition, rapid regulatory changes, and consumer concerns about bacterial contamination and pesticide residues have decreased apple and cider production. Small-acreage apple growers need new strategies to maintain profitability, meet food safety concerns and reduce damage to the environment. The goal of this project is to strengthen the economic viability of apple growers and cider processors as the quality and safety of their products are enhanced. This project takes an integrated approach to solving the interlocking problems of fresh apple and cider safety, environmental stewardship, economics, and federal regulations as they impact the sustainability of rural apple producers and rural communities. The research and outreach phases will focus on growers and cider processors in Iowa as a model for small-scale producers.
The approach is to work with cooperating apple producers and cider processors to develop practical methods to reduce E. coli and other bacteria, fungal blemishes, and pesticide residues and improve the safety of cider to consumers without compromising quality. Outreach and education efforts will target the producers, consumers and students in food science, microbiology, and agricultural education.
The goal of this project was to evaluate the effectiveness of handling and processing treatments for reduction of pathogenic and spoilage microorganisms on apples and cider and to provide relevant information to cider producers and consumers. Sanitizing dips (2 min) of hydrogen peroxide, sodium hydroxide/bicarbonate buffer, Tsunami 100 and Pro-San reduced the number of E. coli O157:H7 inoculants on apples 2.84 to 3.27 log10 in laboratory trials. Pro-San and hydrogen peroxide were more effective than chlorine for destroying pathogens on apples. Post-dip brushing (90 sec) increased fungal removal from apples. On a pilot plant grading line, commercial sanitizers (Pro-San, Kleen 440 and AgChlor 310 in a 7 min dip with 90 sec dry brushing and 20 sec brushing with water), reduced E. coli approximately 1 log10. Brushing reduced the number of E. coli recovered from inoculated apples; however, the effectiveness of brushing was highly variable. A 5-log reduction of E. coli O157:H7 in apple cider was achieved with irradiation at 2.47 kGy. Irradiation and pasteurization reduced the content of fruity and apple-like aromas in cider. Consumers rated pasteurized cider higher than irradiated cider, but both were categorized in the 'like moderately' category. Potassium sorbate effectively reduced yeast and aerobic bacteria counts in cider and reduced the rates of loss of the characteristic flavor compounds and the fermentation of sugars to acids. Irradiated apple cider with sorbate had more intense musty flavor than raw or pasteurized ciders. Oxygen permeability of the packaging materials was important in the retention of flavor during storage. Cider irradiated and stored in polystyrene containers or nylon-6 packaging materials (low oxygen permeability) had lower rates of loss of characteristic flavor compounds compared to non-irradiated apple cider and cider irradiated and stored in low-density polyethylene (high oxygen permeability). Cider irradiated and stored in atmospheric air or nitrogen-flush environments had lower rates of loss for characteristic flavor volatiles compared to non-irradiated apple cider and cider irradiated and stored in an oxygen-flush environment. To minimize losses in flavor quality during storage of irradiated apple cider, packaging materials and handling treatments should minimize oxygen levels in the apple cider. Food safety training and certification was provided to 17 apple cider and 13 other food processors in a workshop, Safe Cider Good Cider, for compliance with the federal regulation and HACCP guidelines. A website (http://www.extension.iastate.edu/foodsafety/) about apple cider processing, HACCP, and food safety was established for food processors and consumers.
This project strengthened the economic viability of Iowa apple producers by assisting them with procedures to assure the safety of apple cider. One hundred percent of the Iowa apple cider producers who pasteurized cider and received HACCP training passed FDA and State of Iowa inspection. These family-owned and -operated businesses employed 55 full-time and 66 part-time employees and produced 100,000 gallons of cider, worth $387,000, in 2004. Sanitizing apple washes, pasteurization or irradiation treatments and sorbate reduced microbial contaminants and increased shelf-life of cider.