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

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

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

4. Apple Juice/Cider Escherichia coli O157:H7
Toronto, Canada fresh apple juice or 14 children had bloody diarrhea and Hemolytic Uremic Syndrome (HUS)
Massachusetts fresh pressed unpasteurized apple cider ill, 16 with bloody diarrhea, 4 with HUS
Connecticut unpasteurized apple cider 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

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

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

7. Apple Juice/Cider Cryptosporidium sp.
Maine - Fair unpasteurized apple cider primary and 53 secondary cases - apples from trees near a cow pasture
New York unpasteurized apple cider confirmed and 11 suspected cases - cause unknown but postulated to be from well water used to rinse apples which was coliform-positive
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.
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

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

9. 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

10. 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

11. 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

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

13. 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

14. 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

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

16. 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

17. 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

18. 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