Microbiological Hazards of Apple Juice/Cider LeeAnne Jackson, Ph.D. Science Policy Analyst Center for Food Safety and Applied Nutrition 1

Outline Outbreaks associated with apple juice/cider Juice processing issues Characteristics of microorganisms 2

Outbreaks associated with Apple Juice/Cider Escherichia coli O157:H7 Salmonella Typhimurium Cryptosporidium sp. 6

Apple Juice/Cider Escherichia coli O157:H7 1980 - Toronto, Canada - fresh apple juice - 13 or 14 children had bloody diarrhea and Hemolytic Uremic Syndrome (HUS) 1991 - Massachusetts - fresh pressed unpasteurized apple cider - 23 ill, 16 with bloody diarrhea, 4 with HUS 1996 - Connecticut - unpasteurized apple cider - 14 ill, 7 hospitalized, 3 with HUS Escherichia coli O157:H7 Canada - E. coli O157:H7 was not isolated from the product or from environmental samples. Massachusetts - Apples were not washed or brushed - no preservatives were used Connecticut - some “dropped” apples were used - apples were washed and brushed - 0.1% potassium sorbate was used 7

Apple Juice/Cider Escherichia coli O157:H7 (cont’d) 1996 - Washington, California, Colorado, British Columbia - commercially produced unpasteurized apple juice - 70 ill, 14 with HUS, one death 1996 - Washington, Church function - unpasteurized apple cider - 6 ill Odwalla - E. coli O157:H7 was cultured from unopened retail containers no cause for contamination was determined Church function: 8

Apple Juice/Cider Salmonella Typhimurium 1974 - New Jersey - 300 ill - cider made from drops from an orchard fertilized with manure Large Processor 9

Apple Juice/Cider Cryptosporidium sp. 1993 - Maine - Fair - unpasteurized apple cider - 160 primary and 53 secondary cases - apples from trees near a cow pasture 1996 - New York - unpasteurized apple cider - 20 confirmed and 11 suspected cases - cause unknown but postulated to be from well water used to rinse apples which was coliform-positive 1993 - Maine - Fair School organized field trip Apples were collected from trees by shaking the trees over a truck and collecting apples from the ground. Apples were stored in wooden crates and rinsed the next morning with municipal water. Cryptosporidium oocysts were detected in the apple cider, on the cider press, and in the stool specimen of a calf on the farm that supplied the apples. 1996 - New York All apples for pressing were purchased from one orchard. The orchard owner reported that only picked apples were sold to the cider mill. Apples were washed and brushed with well water prior to pressing. No preservatives were used. A diary farm was located across the street for the mill. 10

Juice Processing Issues Pressing/squeezing/grinding of fruits and vegetables Bruises / injury Transfer of microorganisms by insects 20

Juice Processing Issues Pressing/squeezing/grinding of fruits and vegetables Exterior contamination Interior contamination Pressing/squeezing/grinding - Recent research has shown that if you place apples in wash water that is cooler than the temperature of the apple, the water will be internalized through the stem scar. If the water contains pathogenic microorganism then they will be internalized as well. No amount of sanitizer applied to the exterior of an apple will eliminate internalized pathogens. Also, any contamination which is present of the exterior of the apple will be incorporated into the juice.. 9

Juice Processing Issues Bruises / injury Point of entry for pathogens - punctures - water Bruises/injury - These can serve as points of entry for pathogens. bruises create soft spots which may allow for the entry of pathogens. Punctures may force pathogens into the interior of the apple. 9

Juice Processing Issues Transfer of microorganisms by insects Fruit flies transmission of E. coli O157:H7 from apple to apple Insects - Recent research has shown that fruit flies can transmit foodborne pathogens (E. coli O157:H7 and apples) 9

Characteristics of Microorganisms Resistance to acid Resistance to preservatives Resistance to sanitizers Resistance to heat Resistance to other control methods 21

Characteristics of Microorganisms Resistance to acid Some strains of E. coli O157:H7 have the ability to survive exposure to acidic conditions for extended periods. Can survive in refrigerated apple juice for most, if not all of the product’s shelf life. E.coli O157:H7 can survive in apple cider with a pH of 3.7 to 4.1 for 14 to 21 days at 4 C and for 31 days at 8 C. 9

Acid resistance of E. coli O157:H7 Acid resistance enhanced by refrigeration Malic acid is one of the gentlest of the organic acids E. coli can be induced to increased acid tolerance by prior exposure to mild acid conditions Have potential for cross protection Survival of E. coli O157:H7 in extremely acidic conditions can be enhanced by preexposing cells to a moderately acidic environment. Acidification is commonly used to control or kill pathogens in foods. Cross protection of acid adapted organisms to heat, osmotic stress and some preservatives. Organisms able to survive in high acid products might survive through gastric acidity. 9

Characteristics of Microorganisms Resistance to preservatives Preservatives are ineffective against Cryptosporidium E. coli O157:H7 in apple cider - 0.1% sodium benzoate - 0.1% potassium sorbate 9

Characteristics of Microorganisms Resistance to sanitizers Chlorine H2O2 Peroxyacetic acid Many sanitizers have been evaluated in the juice industry. Depending on the fruit and vegetable and the pathogen of interest, some sanitizers will be more effective than others. 9

Characteristics of Microorganisms Resistance to heat Storage conditions may influence pathogen destruction Survival of E. coli O157:H7 is enhanced by lowering storage temperature 9

Characteristics of Microorganisms Resistance to other control methods High Hydrostatic Pressure Microwaves Irradiation Pulsed-light High hydrostatic pressure - different pathogens have differing susceptibilities. There are within genera differences - for example some strains of E. coli O157:H7 are more resistant than others. High pressure resistance may also coincide with resistance to certain heat processing temperatures. Microwaves - Some bacteria are more readily killed in water and apple juice than in apple cider. Perhaps this is a factor of the difference in pH of apple juice and water vs. apple cider. Perhaps there was also an effect with the difference in the amount of insoluble solids. Irradiation - E. coli O157:H7 in apple juice can be destroyed with irradiation, however, irradiation effectiveness is very dependent on the food matrix. Pulsed-Light - There is an increased level of inactivation with light pulses of high UV content. 9