Improvement of the Thermal and Alternative Processes for Foods

Non-Technical Summary: Fresh and shelf stable juices in the US have been identified as having violative levels of patulin (greater than 50 ppb). The information on the thermostability of patulin, is lacking. Currently there are no means to remove patulin from contaminated juices and foods and destruction of patulin producing mold species (Penicillium expansum) is the most effective means for prevention. The thermal and chemical inactivation kinetics of P. expansum is unknown and guidelines for US juice manufacturers do not exist. The proposed research will determine the inactivation kinetics of patulin producing molds for thermal processes as well as chemical disinfection agents. The effect of the food propoerties (pH, water activity and texture) on the thermal and nonthermal inactivation kinetics will be examined. The findings will be used to optimize thermal and nonthermal processes to ensure the safety of foods while retaining a premium quality.<P> Approach: Six varieties of fresh apples will be selected based on their use in the cider and juice industry in NY State. The surfaces and cores of different apple varieties will be inoculated by spot and dip inoculation with 10 and 1000 P. expansum spores/apple. The apples will be allowed to dry and then placed in plastic crates and held at 4 degrees C and sampled periodically to assess the extent of exterior and interior rot by extracting and weighing the infected portion of apple tissue. The apples will then be processed to produce the juice. The juice will then be sent for patulin analysis at Trilogy Laboratories (St. Louis, MO). The inoculated apples will also be used to assess the efficacy of chlorine-based and peracetic acid/hydrogen peroxide sanitizers for inactivation of the P. expansum on apple surfaces and cores that are infiltrated at washing steps. Juice containing patulin levels ranging from 50-500 ppb will be treated with commercially available beta glucans extracted from yeast (Diamond V Mills) at varying concentrations ranging from 0.001-0.1 percent and allowed to react with patulin in the juice and allowed to flocculate overnight at 4 degrees C. The juice will be analyzed for patulin levels to determine the optimal glucan concentrations for patulin removal. In addition, glucans will be immobilized in food grade agar or gel beads. The glucan beads will be placed in a filter cartridge that allows for juice to pass over the beads and patulin binding. The filtered juice will be analyzed for patulin levels to determine the extent of patulin removal by the treatment.