# Presentation: 887681

## Apple Cider Production:

- Input Apples - Tree Picked vs. Dropped Apples
- What we know
- What we don’t know
- Why we should take precautions

- Robert I. Merker
- FDA/CFSAN

**Notes:**
The role of input apples in outbreaks associated with contaminated apple cider is a case where guilt by association exists with little hard science.

At this stage, the amount of hard data from controlled experiments is limited, but some concluisions can be made;

Therefore,

I will focus on three areas -
1. What we know
2.  What we don’t know
3.  Why more precautions are now necessary and traditional practices need to be changed.

## The Problem

- Apple Cider / Apple Juice Outbreaks - primarily contamination with *E. coli *O157:H7, some contamination with *Cryptosporidium, Salmonella *spp.
- Association of dropped apples as contamination source in at least one instance.  No unequivocal data to support or refute assertion.
-  Therefore, presumption that input apples were source of contamination.

**Notes:**
The 1990’s have brought us several outbreaks associated with Apple Cider or unpasteurized fresh apple juice.
1991 and 1996 - Outbreaks with E. coli O157:H7 emergent strains far more pathogenic than most of species.
Cryptosporidium
Salmonella

In at least one of the O157:H7 cases, the use of dropped apples was associated with the cider consumed by affected individuals.
This could be caused by contamination of just a few apples or many apples - data explicit cause-effect of dropped apples shown for these outbreaks.

## The Problem [continued]

- In recent outbreaks, contamination usually only present in one batch or a limited number of batches.
- Difficult to discriminate between contamination on apples pre-harvest, or contamination of apples during harvest.
- Probability of finding *E. coli *O157:H7 or *Salmonella *on apples too low.

**Notes:**
Apple Cider 
Usually prepared in relatively small batches, often by smaller processors.  
Contamination usually found to affect only a small number of people - one batch or limited number of lots have been associated with outbreak.
Difficult to establish entry point for contamination by pathogens - even with apples - 
could be pre-harvest / contamination of apples during harvest or as consequence of post-harvest handling practices.
Low likelihood of actually finding O157:H7  or Salmonella on apples  under most circumstances
handful of instances reported in 1990’s - low frequency event.

## Questions: 

- 1.  Are tree picked apples less likely to be contaminated with pathogens than dropped apples?
- 2.  What are the likely sources of contamination with pathogenic microbes?

**Notes:**
The outbreaks with organisms such as E. coli, Salmonella and Cryptosporidium bring out several questions.

1.  Are tree-picked apples less likely to be contaminated (with pathogens) than dropped apples?

2.  What are the likely sources of such contamination?

## Potential Sources of Contamination

- Will vary among different regions, where microbial ecology may vary, but the following general observations may be made.
- Field contamination * likely to be reflected in higher numbers of microbes in dropped apples.
- soil microbes, microbes from contaminated water supplies, microbes from nearby domesticated and wild animals, and insects.
- contamination in harvesting process -hand washing, other precautions.
- In-Plant Contamination
- Post-Processing Contamination

**Notes:**
Sources of contamination will vary among regions, due to different climate and environmental parameters, but some general observations may be made

Field Contamination - likely t o be reflected in higher APC and Yeast and Mold values in dropped apples.
1.  Soil  microbes, microbes from water supplies (which may be contaminated) microbes from domesticated or wild animals, or carried by insects.
2.  Contamination from poor agricultural or harvesting practices.
Other possible sources are In-plant contamination (handling practices or poorly sanitized equipment - biofilms) and Post-Processing contamination, where perhaps,  in bottling or transport of bulk juice, contamination could occur.

## Are dropped apples more likely to be contaminated?

- Presumption would be yes due to contact with agricultural environment on ground.
- Dingman, DW [Connecticut Agricultural Experiment Station, New Haven 06504] 1999.  Prevance of *Escherichia coli* in apple cider manufactured in Connecticut. *J. Food Prot.* 62(6): 567-73.

**Notes:**
Some studies have tried to address the question of whether drops or tree-picked apples are more likely to be contaminated by surveying local producers and attempting to correlate microbial populations on apples and in cider with use of drops. This is a recently published study.

## Conclusions of Recent Study

-  Samples from 11 cider mills
- samples from 6 were positive for *E. coli* at least once during production year. 4% of samples contained *E. coli.**  *
*E. coli * found only in samples produced in mid-late October to January only.
- Found in cider samples produced from October- to-December.
- No correlation of Brix, decrease in acidity to E. coli presence.
*E. coli *found in samples produced from both dropped apples and tree picked apples. NOT O157:H7.

**Notes:**
This study looked at the presence of E. coli  in commercially produced cider in Connecticut.

Samples from 11 cider mills were obtained.
6 positive for E. coli at least once during production year
 E. coli found only in samples produced from mid-late October trough January
	Did not correlate with pH or Brix.
Strains found were NOT O157:H7
Presence of E. coli occurred in samples produced from both tree picked and dropped apples

## A Study in Progress

- Apple Hill - 1998-2000:
- An FDA Cooperative Research Project with El Dorado County California, National Center for Food Science and Technology, University of California, Davis, and USDA.
- Tree Picked vs. dropped apples
- No *E. coli* or coliforms detected in apple and cider samples during October to December period.

**Notes:**
FDA and Collaborators are producing apple cider for research purposes at a cider mill on Apple Hill in Placerville CA

Studies in progress since Fall 1998

No E. coli/coliforms were detected in apples or cider from October to December

## Data Currently Available

- Granny Smith Data: reasonably complete - immediate data on fresh samples only.
- Significant increases in mean APC and yeasts and molds in dropped apples and cider from dropped apples.
- Lauren Jackson - FDA/CFSAN/DFPP
- Patulin found at significant levels in cider produced from dropped Golden Delicious apples, but not detected in cider from tree-picked Golden Delicious or Granny Smith apples.

**Notes:**
Experiments to evaluate the natural microflora of apples are in progress.

From preliminary experiments 

1. Granny Smith apples - significant increases in mean APC and Yeast and mold counts in dropped apple and cider produced from drops.

2.  Lauren Jackson at Division of Food Processing and Packaging in Chicago 
- patulin (mycotoxin) in significant levels in cider from dropped Golden Delicious 
not cider from tree picked or Granny Smith

## APC in Granny Smith Apples and Juice

- Conclusion:  dropped apples may harbor more bacteria, which may get transmitted to the cider

**Notes:**
Left panel shows APC values for tree picked and dropped apples

Right panel shows APC’s for cider from tree picked and dropped apples

## Yeasts and Molds on Apples and in Cider

- Dropped apples appear to harbor more yeasts and molds, which may increase yeasts and molds in juice

**Notes:**
Similarly

Yeasts and molds :

In left panel - values for apple composites

In right panel - values for cider

Tree picked has lower values and mean than dropped.

## Patulin in Cider Produced from Dropped Golden Delicious Apples 1998 season

- Mycotoxin produced primarily by *Penicillium expansum -* apple rot mold.
- Mutagenic, toxic effects in rodents.  Should be no more than 50ng/g in apple products.
- No detectable patulin in cider produced from tree picked apples or dropped Granny Smith Apples

**Notes:**
This graph shows Lauren Jackson’s results on patulin levels in cider producedfrom dropped Golden Delicious Apples
Patulin is mycotoxin produced by apple rot mold Penicillium expansum and related sp.l
Toxic compound mutagen
Should be no more than 50 ng/g in apple products.
Levels reflect source more than preparation method.
None detectable in tree picked apples or Granny Smith apples

## Plans for 1999 Season relative to natural flora on apples

- Determine levels of natural flora on and in apples.
- How do different quality levels, dropped apples, affect on microbial population in cider.

**Notes:**
1999

Look more closely at natural microflora in input apples

Compare how level of quality/culling alters microbial population of cider.

## General Conclusions

- The emergence of *Escherichia coli* O157:H7, some *Salmonella * spp. and *Cryptosporidium* and their association with outbreaks caused by contaminated apple cider has increased the need for information and improved safety practices in apple cider production.
- Dropped apples have been associated with cider  contaminated by pathogens, but no direct evidence of dropped apples as the source of contamination.
- In some regions, generic *E. coli *contamination may occur only during specific portions of the growing season and may be associated with both tree-picked and dropped apples.

**Notes:**
In Summary
Emergence of E. coli O157:H7 and recent contamination with Salmonella and cryptosporidium  and their involvement in cider outbreaks has resulted in increased need for 
more information
improved safety practices in apple handling and cider production
Association of use of dropped apples with contaminated product - no direct evidence by clear association
Some regions 
    Generic E. coli contamination may reflect environmental conditions during portions of growing and harvesting season.
Presence of E. coli may not reflect use of dropped apples.

## Conclusions

- The Apple Hill project has shown the following:
- Patulin was detected only in dropped Golden Delicious apples, not in tree-picked Golden Delicious apples or in Granny Smith apples .
- Detection of patulin alone would be sufficient reason for avoiding use of dropped apples from more susceptible varieties .
- APC and Yeast and Mold levels in dropped apples are higher than those for tree picked apples.
- Therefore the exclusion of dropped apples should yield a higher quality and safer product.

**Notes:**
Apple Hill Project

- Patulin present in unsafe concentration in 
Cider from dropped Golden Delicious 
Not in cider from tree picked Golden Delicious or in any cider from Granny Smith apples

DATA sufficient reason to avoid use of dropped apples from varieties more susceptible to P. expansum  and related molds

- Increased APC and Yeast and Mold levels in dropped apples and cider from dropped apples 

In conclusion:  Exclusion of dropped apples will yield a safer, and higher quality product.