Classroom equipment has been linked to different outbreaks. Surfaces such as tables, chairs, keyboards can harbour pathogens such as Noro virus, Methicillin-resistant Staphylococcus Aureus (MRSA), Influenza A virus and Vancomycin-resistant Enterococci (VRE). Bacteria and viruses can then be transferred to another individual by the mode of touch and leading to potential infections when the individual touches their mouth, nose, eyes or open wound. Institutions usually have their own cleaning and sanitation schedule that covers most of the items in a classroom. However, some common items have been overlooked. Take the project remote controls at the British Columbia Institute of Technology (BCIT) for example. They are often found in filthy condition due to the amount of usage. It is unclear how many sicknesses have been the result of neglecting this device out of their daily cleaning and sanitization schedule. This paper examined the sanitation status of projector remote controls at BCIT. The focus has been placed on major classrooms and laboratories at building SW 1, SW 3 and SE 12 in BCIT. By utilizing the Aerobic Plate Count method, projector remote controls were swabbed using the wet swabbing technique. Swabs were then incubated and results in colony forming units per area in center meter square (CFU/cm2) were collected. A wide range of CFU/cm2 values were observed from projector remote controls. The maximum CFU/cm2 value obtained was 177 and the minimum value was 0. Inferential statistics was performed comparing the mean CFU/cm2 to a stand value of 5 CFU/cm2. Result showed that the mean CFU/cm2 of remote controls in SW 1, SW 3 and SE 12 at BCIT are statistically significantly more than the standard value of 5 CFU/cm2. This suggest that most of the remote controls at BCIT are not in sanitary conditions and BCIT should start to include remote controls into their daily cleaning and sanitization program to prevent students from contracting potential bacteriological infections., Peer reviewed, Peer-reviewed article, Published., Project submitted in partial fulfillment of the requirement for the degree of Bachelor of Technology in Environmental Health, British Columbia Institute of Technology, 2018., Remote control, APC, Equipment, Classroom
Background: Formaldehyde is a volatile organic compound (VOC) present in resins that bind the wood fibre core of laminated flooring products. Installation of laminate flooring involves performing certain procedures that increase the chance of formaldehyde volatilizing into the atmosphere. Exposure to formaldehyde can lead to acute health effects such as watery eyes, nausea, skin irritation, wheezing, and even death. Formaldehyde is also classified as a probable carcinogen and long-term exposure, even at lower doses, may lead to the development of cancers such as leukemia and sinus cancer.
Method: GASTEC formaldehyde 91D passive dositubes were used to quantify the concentrations of formaldehyde present at laminate flooring installation job-sites. The dositubes were worn by two installers who each completed 5 flooring installations over a 15-day period. Between the two installers, there were 3 jobs using Chinese-made laminate, 3 jobs using German-made laminate, and 4 jobs using Canadian-made laminate. A fresh dositube was attached to the belt or collar of each installer at the beginning of the work day and worn while the installer was present at the job-site. In total, 30 samples were collected to which conversion factors were applied to change the units from ppm-hours to an 8-hour time-weighted average TWA. Comparisons were made between Chinese-made, Canadian-made, and German-made laminates and the mean of all 30 readings was compared to the Operational Safety and Health Administration (OSHA) 8-hour TWA standard of 0.75 ppm.
Results: A one-sample T-test indicated that the mean concentration of formaldehyde that the test subjects were exposed did not exceed the 0.75 ppm TWA standard (p=0.000). Further analysis via ANOVA revealed that there was no statistical difference when comparing TWAs stemming from installation of Chinese-made, German-made, and Canadian-made laminate flooring (p = 0.200).
Conclusion: Based on the results, it was concluded that flooring installers working for the Laminate Warehouse in Maple Ridge, BC, are not at risk of developing acute health effects from installing laminate flooring. However, the installers are still exposed to formaldehyde on a daily basis and chronic exposure could increase the risk of developing cancer. In addition, there was no observed relationship between origin of laminate flooring and levels of formaldehyde exposure., Peer reviewed, Peer-reviewed article, Published., Project submitted in partial fulfillment of the requirement for the degree of Bachelor of Technology in Environmental Health, British Columbia Institute of Technology, 2018., Laminate flooring, Formaldehyde, Passive dositubes, Flooring installation, Flooring installers, Occupational hazard
Background: Microblading is emerging as one of the fastest growing beauty trends, appearing in tattoo shops, hair salons, and even in private home studios. The procedure uses a tool with single blade to penetrate the upper layer of the dermis and deposit semi-permanent pigments to mimic hair-like strokes. This study compares the risks of microblading to those in tattooing and analyzes the similarities in order to determine the biological hazards associated with microblading. Currently, there is a lack of knowledge on microblading practices specifically, and the purpose of this study was to evaluate the level of infection control knowledge and practices in place, as well as the attitudes towards regulations in British Columbia.
Method: Self-administered electronic surveys created on Google Forms were distributed to microblading establishments in B.C. through email. The survey assessed the knowledge, attitudes, and practices of microbladers in B.C. through a series of questions regarding demographics, infection control, and wound care. A list of 130 microblading establishments were contacted and asked to participate in the online survey.
Results: Among the 130 microblading establishments contacted, 41 agreed to participate. The majority of microbladers had a college certificate or diploma, 1-5 years of experience, and have taken a bloodborne pathogen course. Over 31% of the participants operated both in microblading as well as permanent makeup, 27% operated solely as microbladers, and 22% of the participants had both microblading and spa operations. The most prevalent form of training was a microblading course that lasted a week or longer, and 78% of the participants felt that there should be more training required for becoming a microblader. There was no association between the years of experience and level of pathogen knowledge according to the Chi square test (p=0.78), and no association between the attitude towards regulations regarding microblading and the number of infection control measures in place (p=0.38). However, there was a statistically significant association between taking a bloodborne pathogen course and knowing the correct bloodborne pathogens of concern.
Conclusion: Microbladers in British Columbia are fairly new and thus only have 1-5 years of experience, and minimal training of week-long microblading courses. A majority of them feel that more training or certification should be required and that there should be more regulations regarding microblading. The results indicated that education and training provide the most knowledge rather than years of experience. This suggests that health authorities should focus on providing more access to education for microblading, such as offering a TattooSafe program for tattooing microblading, and permanent makeup, similar to FoodSafe, and developing more material to inform microblading fact sheets., Peer reviewed, Peer-reviewed article, Published., Project submitted in partial fulfillment of the requirement for the degree of Bachelor of Technology in Environmental Health, British Columbia Institute of Technology, 2018., microbladers, micropigmentation, semi-permanent makeup, permanent makeup, tattooing, infection control, regulations, Microblading
Objective: Sous vide is a relatively new cooking method introduced in restaurants in British Columbia. Sous vide cooking involves placing vacuum sealed food inside a temperature controlled water bath or steam convection oven. Unlike conventional cooking, sous vide cooking involves cooking food at a lower temperature (usually < 65°C) with a longer cook time. The low temperature allows chefs to precisely control the changes within the food. Thus sous vide cooked dishes have consistent texture and color, with retained flavor, moistness and nutrients. With all the benefits, sous vide cooking does have some disadvantages. Lower cooking temperature may not be sufficient for bacterial count reduction, resulting in unsafe food. In addition, every validated sous vide menu requires chefs to precisely follow the cooking temperature and cook time. Any deviation can cause the food to not reach the required 6.5 log reduction in bacterial count. The purpose of this experiment was to determine the effect on the internal temperature of cooking-in-process pork loin packages when additional chilled pork loin packages with an internal temperature of 4°C are submerged into the water bath.
Methods: Two groups of pork loin packages with data loggers inside (SmartButton) at approximately 4°C were introduced into a 60°C water bath at different intervals. The first group (6 packages) was immersed inside the water bath at time = 0 minute, while the second group (6 packages) was immersed inside the water bath at time = 10 minutes. Both groups were taken out when they were cooked for 31 minutes (at time = 31 minutes and 41 minutes respectively). Water bath temperature was recorded using SPER Scientific 8000024 data logger. Temperature data for pork loin packages was used to calculate the mean lethality achieved by each group. One sample t-test and two sample t-test were used for statistical analysis.
Results: There was a more than 3 mean log lethality difference in group A and group B pork loins. Pork loins cooked sous vide style in group A achieved a mean lethality of 5.12 at 31 minutes (range 0.42 to 12.78) while group B pork loins achieved a mean lethality of 8.44 at 31 minutes (range 3.35 to 11.87). With the same cook time, group A had a statistically significantly lower mean lethality than group B pork loins with p value = 0.003. Although statistically inconclusive whether group A pork loins achieved a mean lethality of 6.5, group B pork loins did reach the recommended mean lethality of 6.5.
Conclusion: The result indicated when new cold pork loin packages at 4°C are introduced into a cooking-in-process sous vide water bath at 60°C, the lethality of the original pork loin packages in the bath will be lowered if the cook time remains unchanged. However, it is inconclusive on whether the original pork loin packages will reach 6.5 lethality recommended by BCCDC. The new pork loin packages will reach 6.5 lethality if the original cook time is used., Peer reviewed, Published., Project submitted in partial fulfillment of the requirement for the degree of Bachelor of Technology in Environmental Health, British Columbia Institute of Technology, 2018.
Background: Legionella is a pathogen that causes Legionnaires’ disease in high risk populations. The pathogen is known to exist in plumbing systems that do not have preventative factors in place to prevent its growth and proliferation. Legionella grows between 25˚C and 42˚C and is killed at 60˚C, yet long-term care facilities (LTCFs) reduce accessible hot water temperatures from 60˚C at the hot water tank to less than 49˚C at the taps in order to prevent scalding of their residents. Currently, prevention against scalding takes precedence as temperature at accessible taps is regulated within the Residential Care Regulation (RCR) of the Community Care and Assisted Living Act. It is thought that Legionella proliferation risk can be balanced with scalding in-part through the appropriate installation location of thermostatic mixing valves (TMVs).
Methods: Three LTCFs in Vancouver, British Columbia were selected for environmental sampling for Legionella proliferation risk. At each LTCF the author recorded the type of hot water tank, temperature of water within the hot water tank, the presence of a TMV and temperature of pipes before and after the TMV. As well, the author recorded hot water temperatures after one minute and free available chlorine concentration ([FAC]) at numerous resident-accessible taps throughout each LTCF.
Results: The hot water tank temperatures were set at 60.6˚C, 73.0˚C and 62.0˚C for LTCF #1, LTCF #2 and LTCF #3, respectively. All three LTCFs had installed a TMV within the boiler room immediately after the hot water tank. It was found that LTCF #1’s plumbing system water temperature was reduced from 60.6˚C (at the tank) to 48.9˚C after the TMV. LTCF #2’s plumbing system water temperature was reduced from 73.0˚C (at the tank) to 43.3˚C after the TMV. LTCF #3 was an older plumbing system that did not have thermometers within the boiler room to check the drop in temperature after the TMV. Water temperatures at taps were compared to a standard of 49°C and [FAC] levels at taps to a standard of 0.2 mg/L. The mean hot water temperature and mean [FAC] residual for all three LTCFs were 40.2˚C and 0.27 mg/L, respectively. For all three LTCFs, it was statistically significant that mean water temperatures were less than the comparison value of 49˚C (LTCF #1 p = 0.00000, LTCF #2 p = 0.00022, LTCF #3 p = 0.00110). It was also statistically significant that the mean [FAC] of all three LTCFs were greater than the comparison vale of 0.20 mg/L (LTCF #1 p = 0.00042, LTCF #2 p = 0.00000, LTCF #3 p = 0.00107).
Conclusion: It was found that all three LTCFs had set preventive measures in place to protect their residents. Water was heated to at least 60˚C to prevent Legionella and lowered to less than 49˚C to prevent scalding. [FAC] residual was also adequate to prevent growth of Legionella. However, the location of the TMV in the boiler room was suspected to be a possible contributing factor to Legionella growth, especially if cold water temperatures were to reach 20˚C or above, as they could in warm summer months. Further research is needed to determine the significance of the TMV location and the presence of Legionella., Peer reviewed, Peer-reviewed article, Published., Project submitted in partial fulfillment of the requirement for the degree of Bachelor of Technology in Environmental Health, British Columbia Institute of Technology, 2018., Legionella pneumophila, Legionnaires’ disease, Pontiac fever, Community care facility, Long-term care facility, High risk population, Free available chlorine concentration, Hot water temperature, Hot water, Thermostatic mixing valve
Background: Cross-contamination is one of the leading causes of foodborne illness which poses a massive burden to an individual’s health and to the healthcare system. One way to prevent cross-contamination is through the elimination of pathogens from surfaces by properly washing with a detergent soap followed by sanitizing with a sanitizer. However, as found from a previous research study, not all restaurants in British Columbia wash and sanitize their food contact surfaces. Thus, this study aims to compare the cleaning effectiveness between using detergent soap alone verses using detergent soap followed by sanitizer.
Methods: Aerobic organisms were introduced to a cutting board by cutting alfalfa sprouts and then the surface was cleaned with Dawn Detergent soap and sanitized with 200ppm of chlorine bleach sanitizing solution. 3M™ Quick Swabs were used to sample the aerobic organisms (colony forming units) prior to and after each method of cleaning. The swabs were then transferred to 3M™ Petrifilm Plates, incubated at room temperature for 4 days, and then enumerated.
Results: The results show that there is a statistically significant greater microbial reduction through cleaning with detergent soap followed by sanitizer (mean log microbial reduction of 4.10) as compared to cleaning with detergent soap alone (mean log microbial reduction of 3.53). The p-value obtained is 0.003843 when α=0.05. The power was determined to be 92%.
Conclusions: This study was able to conclude that cleaning with detergent soap followed by sanitizer is 0.57 log (mean log microbial reduction of 4.10 - mean log microbial reduction of 3.53) more effective at cleaning than using detergent soap alone. However, the specific log microbial reduction value for the detergent soap followed by sanitizer achieved in this study is lower than what is found in the previous studies (Gilbert, 1970; Sores et al., 2012; Rossvoll et al., 2015). A possible reason for this discrepancy may be due to the presence of soil and food debris on the surface which may have had interfered with the sanitizing ability of the chlorine bleach (Lee et al., 2007)., Peer reviewed, Peer-reviewed article, Published., Project submitted in partial fulfillment of the requirement for the degree of Bachelor of Technology in Environmental Health, British Columbia Institute of Technology, 2018., Aerobic organism, Colony forming unit, Chlorine bleach, Sanitizer, Sanitizing, Detergent soap, Cleaning, Cutting board, Food contact surface, Cross-contamination, Foodborne illness, Cleaning methods, Log reduction
Background: The hygiene practices of pool patrons are important in maintaining water quality as well as patron health and safety. Poor practices, such as not taking a pre-swim shower, can introduce additional contaminants, which will then react with the free available chlorine to form disinfection by products (DBPs). Not only will excess contaminants decrease the free available chlorine but it will also cause a copious amount of DBPs to be formed. DBPs are known to cause eye and skin irritation, an unpleasant odor, and may cause additional respiratory issues. Therefore, in the interest of public health the number of contaminants introduced into the water should be minimized, which can be done through improving the hygiene practices of patrons. This study investigated factors that may affect pre-swim shower frequencies among aquatic facility patrons.
Methods: Data from 78 respondents to a self-administered electronic survey were used in this study. The survey evaluated respondents’ knowledge of pool related illnesses, knowledge of proper aquatic facility hygiene practices and their attitudes toward these practices. Results were analyzed using one-way ANOVA, chi squared test and independent samples t-test.
Results: The only statistically significant relationship found was an association between the how often an individual used aquatic facilities and their pre-swim shower frequency; frequent aquatic facility users were found to rarely/never take a pre-swim shower (p = 0.049). As well, factors such as knowledge of pool related illnesses, knowledge of proper hygiene practices, age, and if an individual had read the pool rules were not found to be related to pre-swim shower frequency.
Conclusion: The results indicate that educational campaigns aimed at increasing the public knowledge of pool related illnesses and proper pool hygiene practices may not increase pre-swim shower frequencies. Results from this study also indicate that if the showers were cleaner, warmer, and or more private, pre-swim shower frequencies may increase. As well, 79.5% of respondents knew that taking a pre-swim shower is required and 52.6% of participants indicated that they would improve their hygiene practices if consequences were implemented. Taken together, this may suggest that the physical layout of the showering facilities within a swimming pool complex may influence showering behaviour, and greater enforcement of pool rules may be needed in order to increase pre-swim shower frequency., Peer reviewed, Published., Project submitted in partial fulfillment of the requirement for the degree of Bachelor of Technology in Environmental Health, British Columbia Institute of Technology, 2018., Pool, Aquatic facility, Pre-swim shower, Pool hygiene practices
Background & Purpose: The seasonal demand for shellfish such as oysters is on the rise. Shellfish are nutritious foods that may be enjoyed in a variety of ways, from slurping raw oysters to cooking oysters by means of boiling, steaming, pan frying and baking. Most consumers of oysters are aware of potential food safety issues with shellfish. Raw or undercooked shellfish can carry bacteria, viruses and toxins, potentially resulting in foodborne illness. Past outbreaks associated with the consumption of raw and undercooked oysters, prompted the British Columbia Centre for Disease Control (BCCDC) to develop guidelines for those preparing, cooking and consuming shellfish. The recommended cooking temperature and time from the guideline was compared with the temperature and time of standard cooking methods from the Fanny Bay Oyster Market restaurant. The purpose of this project was to determine whether standard cooking methods from restaurants attain the guideline’s recommended 90oC for 90 seconds.
Method: Four common cooking methods of Oysters were chosen based on recommendation from Chef Chris Andraza and BCCDC researcher Lorraine McIntyre. Oysters were pan fried, deep fried, baked and grilled. Internal temperatures of cooked oysters were then measured with a probe thermometer. Results for each method were analyzed and compared with the standard of 90oC using the one sample t-test from the statistical software package, NCSS11.
Results: One sample t-tests showed statistically differences from the deep fried, baked and grilled methods when compared to the standard of 90oC (p = 0.000). The power for all three methods was 100%, therefore there is confidence that the findings reflect the truth. Experimental temperatures were consistently less than the standard. The pan fried method showed no statistically significant difference when compared to the standard of 90oC (p = 135). The power for pan fried method was 29.2%, therefore there is limited confidence that the findings reflect the truth. Therefore the deep fried, baked and grilled methods required additional cooking time to raise internal temperatures of the oysters. Whereas the pan fried method had achieved the standard but further experimentation is required to eliminate the chance of a type II error.
Conclusion: It can be concluded that three out of the four cooking methods (deep fried, baked and grilled) can have significantly different mean temperatures. However, different thermal preparation methods prior to final thermal processing requires consideration to determine cooked oyster consumption safety. One out of the four cooking methods (pan fried) attained the standard temperature 90oC. Therefore, it is recommended for deep fried, baked and grilled cooking methods that the cooking time be extended to achieve an internal temperature of 90oC or higher., Peer reviewed, Peer-reviewed article, Published., Project submitted in partial fulfillment of the requirement for the degree of Bachelor of Technology in Environmental Health, British Columbia Institute of Technology, 2018., Cooked Oyster, Temperature, Recipes, Restaurant
Background: The average Canadian spends approximately 90% of their day indoors, a proportion of which may be in public spaces, thereby making Indoor Air Quality (IAQ) a pertinent topic for the fields of Public and Environmental Health. Mould complaints are one of the top IAQ complaints received by Environmental Health Officers (EHOs) in BC. Mould is ubiquitous in both the outdoor and indoor environment. However, once indoors, mould will grow unhindered on most surfaces as long as moisture is present. Accumulating evidence has established relationships between indoor environments and health. Thanks to the Internet, the amount of readily available information regarding mould today is vast but may not necessarily be valid nor reliable. It is important, therefore, to consider what the public does or does not know and where they are getting their information. This study evaluated the public perception of Metro Vancouver residents in regards to mould as an IAQ issue in order to provide Public and Environmental Health practitioners, including EHOs, with a deeper understanding of how to effectively address queries from the public regarding this topic.
Methods: Data for this study was collected through a self-administered online questionnaire and disseminated using social media and the snowball effect. Questions were designed to collect demographic information and evaluate the knowledge and attitudes as well as the behaviour and practices of participants. Descriptive and inferential statistics, specifically the independent samples t-test and the analysis of variance (ANOVA), were used to analyze the results.
Results: With an average 14.59 out of 20 points, respondent knowledge scores were, in general, fair. There was no statistically significant difference between respondent knowledge score and their gender, age, level of education, income or housing status.
Conclusions: Although respondent knowledge scores were fair, a few gaps in knowledge were identified. Further, most of the sample population did not know specifically where to access reliable information on mould. These insights may be useful for Public and Environmental Health professionals when addressing queries from the public regarding this topic., Peer reviewed, Peer-reviewed article, Published., Project submitted in partial fulfillment of the requirement for the degree of Bachelor of Technology in Environmental Health, British Columbia Institute of Technology, 2018., Mould, Mold, Indoor air quality, Indoor environment, Environmental health, Public health, Knowledge, Metro Vancouver, British Columbia
Background: Incidence rates of some foodborne illnesses (FBIs) in BC still remain on the rise despite numerous initiatives to prevent FBIs. This rise over the years has been attributed to gaps in the public’s food-safety knowledge and practices. In order to decrease incidence rates and prevent future FBIs, efforts should be made to identify common misconceptions in the public’s food safety knowledge. With a focus on the Metro Vancouver population, common misconceptions in food safety were found and their knowledge level towards the misconceptions was analyzed.
Methods: An in-person survey was conducted in three locations in Metro Vancouver. The survey asked for demographics information, perceived food safety knowledge and food safety misconceptions. ANOVA and Independent Sample T-test were administered to analyze results.
Results: No statistically significant difference in food safety knowledge was found between groups by gender, age, and geographic region. The majority of participants rated their food safety knowledge as moderate but they demonstrated a poor knowledge level in food safety.
Conclusion: The public’s knowledge level should be improved to prevent further rises of FBIs. Initiatives involving the provincial Foodsafe certification program, secondary school curriculums and health authority websites can be utilized to educate the public., Peer reviewed, Peer-reviewed article, Published., Project submitted in partial fulfillment of the requirement for the degree of Bachelor of Technology in Environmental Health, British Columbia Institute of Technology, 2018., Food safety, Misconceptions, Knowledge, Foodborne illness
Vancouver is located in a generally low-radon hazard zone. However, other parts of British Columbia such as the BC Interior or Northern BC are classified as high-radon hazard zone (or zone 1) due to the geological composition of rocks and soils in those areas. Despite the significant health risks associated with radon gas exposure, many BC residents and people across Canada have little to no knowledge regarding the topic. Since Post-secondary schools, such as the British Columbia Institute of Technology (BCIT), are places where knowledge is distributed and shared to our societies, it is important to assess students’ general knowledge background regarding radon gas. The result can then be extrapolated to the general populations.
An electronic survey was conducted to determine whether students in the six schools at BCIT have different background knowledge level regarding radon gas. The survey also determines students’ radon background knowledge based on different geographic regions they reside. The survey was conducted in-person at three main locations across BCIT’s Burnaby campus. It was administered using Google Forms and distributed to participants on Microsoft Surface 2.
The One-way ANOVA statistical analysis result indicated that there is a significant difference in mean radon survey scores among the six various BCIT schools(p=0.009). In addition, the Tukey Test revealed that students from the School of Health Science have an average radon survey score which is significantly different when compared to students from the School of Business. However, it was found that there is no significant difference in the mean radon survey scores between the School of Business and other schools at BCIT. Nonetheless, it was evident that the School of Health Science students had relatively higher radon survey scores and thus, were more knowledgeable regarding radon gas compared to students from the other five schools.
When analyzing survey scores among students residing in various geographic regions, the test showed that there is no significant difference in mean radon survey scores among BCIT students living in various geographic locations(p=0.46).
Based on the result of the study, the result showed that there is a significant difference in radon gas knowledge among BCIT students who majored in different schools. The School of Health Science students were more knowledgeable regarding the topic of radon gas compared to students in other schools. Nonetheless, all BCIT students achieved an average radon survey score of less than five out of ten, which was considered a failure score (Less than five out of ten). This showed that most BCIT students had very limited knowledge regarding radon gas and there were very limited amount of educational initiatives or campaigns available for students at BCIT. BCIT’s student association is recommended to create educational sessions across campus to raise student awareness regarding radon gas. At the community level, governments and various agencies such as the BC Lung Association need to work together to create radon awareness campaigns across BC and the rest of Canada. In order to get a more accurate representation of the radon gas knowledge level among people in BC, more research studies need to be conducted in other schools or general population groups., Peer reviewed, Peer-reviewed article, Published., Project submitted in partial fulfillment of the requirement for the degree of Bachelor of Technology in Environmental Health, British Columbia Institute of Technology, 2018., Radon, Survey, School, BC, Knowledge, Lung, Cancer, Risk
Background: In the culinary industry, sous vide is a popular cooking method in which lower temperatures are used to cook food to retain more desirable organoleptic characteristics. However, this technique may compromise food safety as the temperature may not be sufficient enough to eliminate pathogens that may be present. The BCCDC’s Guidelines for Restaurant Sous Vide Cooking Safety in British Columbia advises when too many food items are placed in the sous vide water bath, inadequate water circulation may occur with the result that process lethality, measured by calculation of log10 reductions, may not be achieved. The purpose of this study was to determine how overcrowding a sous vide water bath would impact the thermal process of pork loins.
Methods: Each pork loin sample had a SmartButton inserted and was vacuum sealed in a plastic bag. The water bath was preheated to 60˚C by an immersion circulator. Under normal conditions, six pork loin samples were held in the water bath for 1 hour and the process was repeated four more times. Under overcrowded conditions, two runs were conducted for 1.5 to 2 hours, each consisting of 15 samples stacked in three layers. SmartButton temperature values were used to calculate whether a 6.5 log10 reduction for Salmonella spp. was achieved, using the American Meat Institute’s formula.
Results: Using a 31-minute cook time, pork loins in normal conditions reached an average log reduction of 8.85 (range: 0.51 to 21.07), which was significantly higher than the 6.5 log10 reduction objective (p = 0.006). Conversely, pork loins in overcrowded conditions reached an average log reduction of 1.76 (range: 0.05 to 7.93), which was significantly lower than the 6.5 log10 reduction objective (p = 0.000). Furthermore, cooking lethality between the two conditions, pork loins in crowded and overcrowded conditions, were found to be significantly different from each other (p = 0.000). No differences were found in the mean log10 reductions between the pork loins placed in each of the three layers in an overcrowded water bath at 31 minutes (p = 0.094).
Conclusion: Overcrowding sous vide water baths does impact on the thermal process of pork loins. Food products cooked under overcrowded conditions require a longer cook time, (approximately 30 minutes longer) to achieve at least 6.5 log10 reductions. Therefore, it is advised that food handlers using sous vide techniques should avoid overcrowding sous vide water baths. Further research using more samples is recommended to determine potential cold spot patterns in overcrowded water baths due to inadequate water circulation., Peer reviewed, Peer-reviewed article, Published., Project submitted in partial fulfillment of the requirement for the degree of Bachelor of Technology in Environmental Health, British Columbia Institute of Technology, 2018., Sous vide, overcrowding, water bath, pork loin, temperature, public health