Food microbiology – Targeted surveys – Final report
Summary
A 2-year targeted surveyFootnote 1 analysed 787 samples of dried coconut for the presence of the pathogens Salmonella species (spp.), Staphylococcus aureus (S. aureus), Bacillus cereus (B. cereus), and Clostridium perfringens (C. perfringens). All samples were also tested for generic Escherichia coli (E. coli) which is an indicator of the overall hygienic and sanitary conditions of the food supply chain from production to the point of sale.
All of the samples tested were found to be satisfactory. Salmonella spp., S. aureus (>104 CFU/g), B. cereus (>106 CFU/g), C. perfringens (>106 CFU/g), and generic E. coli (>102 MPN/g) were not found in any of the samples.
Overall, our survey results indicate that dried coconut sold in Canada is generally safe for consumption. However, as with all foods, and especially with those that are ready for consumption without further preparation or cooking, good hygienic practices are recommended for producers, retailers, and consumers.
Why was this survey conducted
The survey was conducted to generate baseline information on the quality and safety of dried grated coconut sold at retail in Canada.
Dried coconut is a food that is widely available at retail in CanadaFootnote 2. It is often eaten directly as a snack or can be used as an ingredient in many prepared foods, such as granola bars, cookies, smoothies or savory dishes. In many cases, dried coconut is added as a topping and consumed without further preparation or cooking.
Various methods are used to make dried coconut, however the process involves the drying of raw coconut meat in a controlledFootnote 3 (oven, kiln) or uncontrolledFootnote 4 (exposure to the sun, open air) environment. If contamination occurs at any point in the food production chain, pathogens can survive for long periods of time due to the low moisture and high fat content of dried coconut.
Unfortunately, dried coconut has been associated with recallsFootnote 5,Footnote 6 and outbreaksFootnote 7,Footnote 8 of foodborne illness as they can become contaminated with pathogens during production, harvest, post-harvest handling, processing, packaging, distribution and/or at retail. When consumed, the presence of bacterial pathogens creates the potential for foodborne illness.
When was the survey conducted
The survey was conducted over a 2-year period from April 1, 2019 to March 31, 2021.
Where were the samples collected from
Samples were collected from national retail chains and local/regional grocery stores located in the following 11 major cities across Canada:
- Halifax
- Moncton
- Quebec City
- Montreal
- Toronto
- Ottawa
- Vancouver
- Victoria
- Calgary
- Saskatoon
- Winnipeg
The planned number of samples to be collected from each city was based on the population of the province in which the city was located relative to the total population of Canada.
How many and what kind of samples were collected
A total of 787 pre-packaged dried coconut samples were collected. A variety of product types were selected to represent varying degrees of processing (chunks, flaked, shredded, powdered). A sample consisted of a single or multiple consumer sized packages of the same lot weighing at least 250g.
What were the samples tested for
All samples were tested for Salmonella spp., S. aureus, B. cereus, C. perfringens, and generic E. coli. Salmonella spp., S. aureus, B. cereus, and C. perfringens are pathogenic bacteria while generic E. coli is an indicator of the overall hygienic and sanitary conditions under which the samples have been produced, processed, stored, and transported.
What methods were used to test the samples
Samples were analyzed using analytical methods published in Health Canada's Compendium of Analytical Methods for the Microbiological Analysis of FoodsFootnote 9 that were appropriate for the testing of dried coconut.
How were the samples assessed
The samples were assessed using criteria based on the principles of Health Canada's Health Products and Food Branch Standards and Guidelines for Microbiological Safety of Food – An Interpretive SummaryFootnote 10, the International Commission on Microbiological Specifications for FoodsFootnote 11, the Food and Drugs ActFootnote 12 (Section 4(1)) and guidelines developed by international food safety authoritiesFootnote 13,Footnote 14.
| Bacteria | Satisfactory | Investigative | Unsatisfactory |
|---|---|---|---|
| Salmonella spp. | Not detected | Not applicable | Detected |
| S. aureus | ≤ 104 CFU/g | > 104 CFU/g | Not applicable |
| B. cereusTable Note a | ≤ 106 CFU/g | > 106 CFU/g | Not applicable |
| C. perfringens | ≤ 106 CFU/g | > 106 CFU/g | Not applicable |
| Generic E. coli | ≤ 102 MPN/g | > 102 MPN/g | Not applicable |
No assessment guidelines had been established in Canada for the presence of bacterial pathogens or indicator organisms in dried coconut at the time of writing this report.
As Salmonella spp. is considered pathogenic to humans its presence was assessed as unsatisfactory as it is considered to be a violation of the Food and Drugs ActFootnote 12 Section 4(1)a.
B. cereus, S. aureus,and C. perfringens can produce toxins capable of causing foodborne illness and therefore their presence at elevated levels was assessed as investigative, possibly resulting in further follow-up actions.
Unlike bacterial pathogens, most strains of generic E. coli are harmless. Generic E. coli is considered to be an indicator organism as their levels present in a food product are used to assess the overall sanitation conditions throughout the food chain from production to the point of sale. Their presence at some levels is tolerated, however elevated levels were assessed as investigative, possibly resulting in further follow-up actions.
What were the survey results
All of the samples tested were found to be satisfactory. Salmonella spp., S. aureus (>104 CFU/g), B. cereus (>106 CFU/g), C. perfringens (>106 CFU/g), and generic E. coli (>102 MPN/g) were not found in any of the 787 samples tested.
| Bacterial analysis | Number of samples tested | Satisfactory (%) | Investigative | Unsatisfactory |
|---|---|---|---|---|
| Salmonella spp. | 787 | 787 | Not applicable | 0 |
| S. aureus | 0 | Not applicable | ||
| B. cereus | 0 | Not applicable | ||
| C. perfringens | 0 | Not applicable | ||
| Generic E. coli | 0 | Not applicable | ||
| Total | 787 | 787 (100.0) | 0 | 0 |
Survey results are also presented by production practice (table 3), origin (table 4), and product type (table 5).
| Production practice | Number of samples tested (%) | Satisfactory |
|---|---|---|
| Conventional | 536 (68.1) | 536 |
| Organic | 251(31.9) | 251 |
| Total | 787 (100.0) | 787 |
| Product origin | Number of samples tested (%) | Satisfactory |
|---|---|---|
| Import | 431 (54.8) | 431 |
| UnknownTable Note b | 356 (45.2) | 356 |
| Total | 787 (100.0) | 787 |
| Product type | Number of samples tested (%) | Satisfactory |
|---|---|---|
| Dried coconut chunks | 46 (5.8) | 46 |
| Dried coconut flakes | 115 (14.6) | 115 |
| Dried shredded coconut | 557 (70.8) | 557 |
| Coconut flour | 69 (8.8) | 69 |
| Total | 787 (100.0) | 787 |
What do the survey results mean
No previously published studies on the microbiological quality or safety of dried grated coconut were found at the time of writing this report. A previous CanadianFootnote 15 study was conducted by the CFIA on the microbial quality and safety of fresh-cut fruits sold at retail including coconut. E. coli O157, Listeria monocytogenes, Salmonella spp., Shigella, and generic E. coli (> 100 CFU/g) were not found in any of the 20 fresh-cut coconut samples tested.
Overall, our survey results indicate that dried coconut sold in Canada is generally safe for consumption. However, as with all foods, and especially with those that are ready for consumption without further preparation or cooking, good hygienic practices are recommended for producers, retailers and consumers.
What is done with the survey results
All results are used to inform risk management decisions and support program design and re-design.
Can I access the survey data
Yes. The data will be accessible on the Open Government Portal.