Bacteria on Stainless Steel Surfaces | Experiment

bacteria on Stainless Steel Surfaces ExperimentThe attachment of bacteria on nutrition affect draw closes and in the environment so-and-so ca employment la disco biscuitt spread over- pollution, which earth-closet lead to pabulum spoilage, possible feed safety cites, and start destruction. aliment come to nears used for nutriment handling, storage or processing be disciplines where microbic taint commonly occurs. Even with proper cleanup spot and sanitation regimes or practices in place, bacteria can remain affiliated to the come to the fores and this attachment can lead to biofilm formation. The purpose of this study was to find out the social movement of pathogenic microorganism in a food processing atomic number 18a and to evaluate the effect of the alter procedure on the microbial commove in the food processing area. x replicate food shock scratchs were heared unblemished marque, marble and timberlandland, with contiguous areas being sample d forwards and by and bywards make clean. The test draw nears were analyzed with a mop up method in the lead and aft(prenominal)wards(prenominal) the modify acquaint. The forces of these studies indicate that troika of ten untarnished trade name step to the fore were begrime in the lead make clean and no surface was pollute by and by cleanup position. Furthermore, three out of ten marble surfaces were contaminated forward make clean and single surface was contaminated later on killing. sise of ten wood surfaces were heavily contaminated originally cleanup spot and three surfaces were contaminated after modify. The difficulty in cleanup was related to the amount of surface constipation and it is best to avoid this type of surface. Hypochlorite ancestor that was used for change the surfaces in this study was considered to be effective against the foodborne pathogens tested. This study has highlighted the fact that pathogens remain execu panel on ju iceless home runless steel surfaces and present a contamination hazard for considerable periods of time, dependent on the contamination take aims and type of pathogen.Keywords Microorganisms natural selection Cross-contamination Food have-to doe with surfaceInt magnetic poleuctionFood clashing surfaces are the chief denizen of biofilm that can host potenti totallyy harmful microorganisms. This, therefore, is a prominent phenomenon in food processing plants owing to dregs and residues of all sorts chemical, biological, organic, and/or inorganic -which build up on the surfaces of equipments that whitethorn claim in contact with food (Mafu et al. 2010). The presence of these undesirable microorganisms to the material surfaces is a source of concern, as this can depart in food cross-contamination, direct to food insobriety. Under favourable circumstances (temperature, pH, relative humidity), pathogenic microorganisms are able to survive and/or replicate on a too large scale w ithin the biofilm. In domestic kitchens and food processing industries, foodborne affection can turn out from incorrect storage of foods, smashicularly with respect to temperature, contamination of raw or cooked foods in the first place consumption, by contact with other foods or utensils (food contact surfaces ) carrying pathogens, and inadequate cleanup spot procedures that may not see have sex removal of microorganisms (Teixeira et al. 2007).In food processing industries, food contact surfaces, such(prenominal) as innoxious steel, marble and wood may create an change environment for the natural selection of the microorganism, starring(p) to serious hygienic problems. Furthermore, dead ends, corners, joints, valves and every other hard-to-reach places are the most appropriate areas for the presence of bacteria. (Peng et al. 2001).The value of support and disinfection processes in food processing industries depends, to a large extent, on the flesh and maintenance progra mmes adopted by the company.Lack of efficacy in cleaning procedures may allow persistence and survival of pathogens in foods owing to their legitimate adherence to food contact surfaces. This may lead to transfer of microorganisms from nation, objects or contaminated food to other food or material, hence leading to cross-contamination. People can, in umpteen ways, be a source of cross-contamination to foods (Holah and Thorpe, 1990).Food can be contaminated when it is handled, so it is very important that people who may be carrying or suffering from certain diseases do not handle food. Contamination can also be passed from equipment when contacting food. It particularally happens when utensils or equipment are not efficiently cleaned and sanitized between each use and may lead to development of biofilm, creating favourable conditions for the survival of the pathogens. Contamination from food to food occurs mainly when raw foods come into contact with cooked or brisk foods (Montv ille et al. 2001).The persistent presence of microorganisms in food processing factories, specifically on food contact surfaces despite deliberate efforts to combat the phenomenon, poses huge challenges to the company. It trends the addition margins of the industries due to the increased cost incurred in the attempts to adopt advanced cleaning services and programmes. A potential effect of the presence of microorganisms on food surfaces is food poisoning. Occurrence of food poisoning depart mean great pervert to the image of the company and persistent stress on the part of the management, thus derailing the progress of the company.Cross contamination is also becoming a common problem both in the kitchen setting and in industry. carry of resistant pathogens and microorganisms across and a enlarge these food p roducers through various(a) agents and factors that circulate and carry the pathogens is a health hazard. Studies show that the level of contamination varies depending o n the duplication and the rate of material handling that occurs in the factory. In this context, therefore, workers hands, utensils and the blanket(a) extension of all food contact surfaces contribute to in cross contamination (Zhao et al. 1998).A thorough examination of the whole concept of microbial survival and persistence on food contact surfaces despite common cleaning procedures and revised designs of the food contact surfaces (such as textural properties, maintained good surface hydrophobicity) will reveal that more detailed analysis and studies should be focused on the factors that create an enabling environment for the persistent counterpunch and presence of the foodborne pathogens in the food processing industries and kitchen setting (Scott and Bloomfield, 1990). The study of various relevant properties for the microbial adhesion process has been another imperative finishing of this study and the purpose behind it is to obtain a broader knowledge bagful of the mechan isms of bacterial adhesion to food contact surfaces so as to muse strategies for its control.The objective of this study is to identify the microorganisms that can survive in the food contact surface, such as stainless steel, marble and wood, change surface after cleaning procedures, thus increasing the risk of food cross-contamination. The study will focus on microorganisms that survive in the food processing areas even after the cleaning procedure. Foodborne pathogenic bacteria adhere to inert surfaces they may exhibit a greater scale of resistance to chemical or ordinary cleaning and fumigating agents (Barnes et al. 1999). The concept of cross contamination is of major concern in the food processing industries that constitute a threat to homophile health because they cause most food borne illness outbreaks. Food poisoning is one of the consequences of adherence of microorganisms to food contact surfaces (Sattar et al. 2001).Materials and MethodsPremisesIn assure to assess the microbiological safety of a food processing area in Oman, three types of food contact surfaces were studied Stainless steel, marble and wood. Ten surfaces of each of the three types were tested, with the adjacent areas of each one being sampled onward and after cleaning. This study was performed randomly in nineteen selected Army camps kitchen.selective information analysisSwabs were taken from the food processing area within the proud Army camps kitchen and sent to the food microbiology laboratory of the environmental of health unit for analysis. The swabs were each tested for pathogenic bacteria linked with food and coliforms that can survive on the surface of food conceptualisation areas in advance and after cleaning. The crustal plates were read for the number of colonies of pathogenic bacteria and coliforms. A Phoenix railroad car was used to identify the bacteria and readings were taken directly from the Phoenix political machine. A Phoenix is automated microbiology s ystem is intended to provide rapid recognition events for most aerobic and facultative anaerobic gibibyte confirmative bacteria as well as most aerobic and facultative anaerobic Gram negative bacteria. The designation of the Phoeonix panal uses a series of conventional, chromogenic and fluorogenic biochemical tests to identify the organism. The growth-based and enzymatic substrates are employed to cover the different types of reactivity among the diverge of taxa. The tests are based on the use of bacteria and declivity of specific substrates sight by different indicator systems. Acid production is indicated by a change in phenol red indicator when an confiscate is able to utilize a carbohydrate substrate. A yellow twist is produce by Chromogenic substrates upon enzymatic hydrolysis and the enzymatic hydrolysis of fluorogenic substrates go aways in the release of a fluorescent coumarin derivation. Organisms that utilize a specific carbon source reduce the resazurine based indicator. These solutions were recorded and the log reduction was calculated for each plate at each dilution rate after and in front cleaning of the surface (BD Phoenix, 2007). ingest methods and microbiological examination (Before Cleaning)Tests using the swab method were carried out on surfaces contaminated with food borne pathogens in a food processing area. Tubes containing 10 ml of sterile buffered peptone saline solution were used to wet the swabs preceding to sampling. Cotton swabs were removed from their sterile packaging and were held by the stick composition they were moistened with buffered peptone saline solution, the excess broth was returned into the bottle. All surfaces were nimble in sizes of 20 x 20 cm2 for survival experiments. The swabs were rotated while in contact with the food preparation surface. subsequently the defined area was swabbed, the swab was returned to the test tube containing the buffered peptone saline solution to dislodge the bacteria. se ries dilutions of the swab solutions were prepared and duplicate pour plates were prepared for each dilution using nutrient nutrient nutrient nutrient agar-agar-agar, MacConkey agar and riptide agar. The plates were incubated for 24 hours at 37oC.Sampling methods and microbiological examination (After Cleaning)The surfaces were washed with earnest water and chemical detergent and indeed rinsed with hot water. Then the surfaces (stainless steel, marble, and wood) were disinfected with 5.25% of hypochlorite solution for 10 minutes. The surfaces were allowed to teetotal before sampling. The swabbing method used was as above. Duplicate pour plates were prepared for each dilution using nutrient agar, MacConkey agar and crinkle agar. The plates were incubated for 24 hours at 37oC.Sampling methods and microbiological examination (Control) just about of the food borne pathogen strains used as a control for these experiments on the surfaces (stainless steel, marble, and wood), such as staphylococci aureus and Escherichia coli were obtained from the Armed Forces Hospital Laboratory. For their control strains a clean stainless steel table without tiny groove was prepared as the food contact surface because it can be fabricated with a fine-tune cleanable finish. The table also was disinfected with 5.25 % of hypochlorite solution for 10 minutes. The surface was then washed with hot water, with chemical detergent and rinsed with hot water. The surface was allowed to dry before sampling. The test suspensions were prepared by making serial dilutions of the microorganisms in peptone saline solution. Two different levels of contamination were prepared high contamination (approximately 106 dependency forming units (CFU)/ deoxycytidine monophosphate cm2) and low contamination (approximately 103 CFU/ hundred cm2), obtained by scatter 1 ml of an appropriate solution on a surface of 20 x 20 cm2 over the grid reference table. The table was allowed to dry for 15 minutes t o represent the environment of food preparation area. Selective agar media were used for the enumeration of pathogens Blood agar for Staphylococcus aureus, incubated for 24 hours at 37oC and MacConkey agar for Escherichia coli incubated for 18 24 hours at 37oC. Furthermore, the personal effects of deuce different contamination levels on the survival of pathogens on dry stainless steel surfaces for 24 hours at room temperature were investigated.Resultmicrobic survival on food contact surface (stainless steel surface) evade 1 The Colony descriptions of the microbial survival on stainless steel surface prorogue 1 shows the Colony descriptions military issue of the microorganisms isolated from stainless steel surface. Three of ten stainless steel surface were contaminated with bacteria before cleaning. defer 2 The resolution count of the microbial survival on stainless steel ingest no(prenominal)Serial ten-fold dilutions in deionised water diluentscolony count (CFU ml-1) before clean ingcolony count (CFU ml-1) After cleaning23.2 x 102bacteria non notice62.6 x 102 bacterium not observe94.3 x 102bacteria no(prenominal) detect delay 2 shows the allow of the colony count obtained before and after cleaning of the stainless steel surface.Table 3 Gram stain result of the microbial survival on stainless steel surface exemplar no(prenominal)2Gram stain resultGram negative, rod term audition no6Gram stain resultGram positive cocci prototype No.9Gram stain resultGram negative, rod shapeTable 3 show the result of the Gram stain of bacteria that were isolated from the stainless steel surface before and after the cleaning symbolize. exemplar No.2 ensample No. In phoenix machine344Name of bacteria find before cleaningKlebsiella aerogenesName of Bacteria spy After cleaningnot detect ensample No.6 savour No. In phoenix machine367Name of Bacteria detected before cleaningStaphlococcus aureusName of Bacteria detected After cleaning non detected take in No.9 savour No. I n phoenix machine382Name of Bacteria detected before cleaningKlebsiella aerogenesName of Bacteria detected After cleaningNot detectedTable 4 The Identification of bacteria by phoenix machine that survived on the stainless steel surface before the cleaning stageTable 4 show the result of bacterial identification that obtained by phoenix machine which was isolated from stainless steel surface before and after the cleaning stage.Microbial survival in food contact surface (Marble surface)Table 5 The Colony descriptions of the microbial survival on marble surface ingest of location No.1 nutritious agarNo ingatheringMacConkey agarNo step-upBlood agarNo ontogenesisSample of location No.2 food agarNo growthMacConkey agarNo emersionBlood agarNo processSample of location No.3 nutrient agarNo step-upMacConkey agar bump in glossiness, mucoidBlood agarwhite, large and mucous coloniesSample of location No.4Nutrient agarNo fruitMacConkey agarNo exploitationBlood agarNo GrowthSample of lo cation No.5Nutrient agarNo GrowthMacConkey agarNo GrowthBlood agarsmooth, round, grayish-white coloniesSample of location No.6Nutrient agarNo GrowthMacConkey agarNo GrowthBlood agarNo GrowthSample of location No.7Nutrient agarNo GrowthMacConkey agarNo GrowthBlood agarNo GrowthSample of location No.8Nutrient agarNo GrowthMacConkey agarNo GrowthBlood agarNo GrowthSample of location No.9Nutrient agarNo GrowthMacConkey agarNo GrowthBlood agarNo GrowthSample of location No.10Nutrient agarSmall circular colonies, yellow in colourMacConkey agarNo GrowthBlood agarswarming motilityTable 5 shows the colony descriptions result of the microorganisms isolated from the marble surface. Three of ten marble surfaces remained contaminated with bacteria before and after cleaning.Table 6 The colony count of the microbial survival on marble surfaceSerial dilutions in deionised water diluentscolony count (CFU ml-1) before cleaningcolony count (CFU ml-1) After cleaningSample No.3*TFTCBacteria Not Detecte dSample No.55.1 x 102Bacteria Not DetectedSample No.10TMTCTMTC*TFTC alike Few To Count TMTC Too Many To CountTable 6 shows the result of the colony count obtained before and after cleaning stage of marble surface.Table 7 Gram stain result of the microbial survival on marble surfaceSample No.3Gram stain resultGram negative, rod shapeSample No.5Gram stain resultGram negative, rod shapeSample No.10Gram stain resultGram negative, rod shapeTable 7 show the result of the Gram stain of bacteria that was isolated from the marble surface before and after the cleaning stage.Table 8 The Identification of bacteria by phoenix machine that survived on the marble surface before the cleaning stageSample No.3Sample No. In phoenix machine301 MarbleName of Bacteria detected before cleaningKlebsiella pneumoniaName of Bacteria detected After cleaningNot DetectedSample No.5Sample No. In phoenix machine326 MarbleName of Bacteria detected before cleaningYersinia enterocoliticaName of Bacteria detected Aft er cleaningNot DetectedSample No.10Sample No. In phoenix machine381 MarbleName of Bacteria detected before cleaningProteus vulgarisName of Bacteria detected After cleaningProteus vulgarisTable 8 show the result of bacterial identification that obtained by phoenix machine which was isolated from marble surface before and after the cleaning stage.Microbial survival in food contact surface ( forest surface)Table 9 The Colony descriptions of the microbial survival on wood surfaceSample location No.1Nutrient agarNo GrowthMacConkey agarNon-lactose fermenters coloniesBlood agarWhite, non hemolytic coloniesSample location No.2Nutrient agarNo GrowthMacConkey agarNo GrowthBlood agarNo GrowthSample location No.3Nutrient agarsmooth, unmistakable large colonies , greenish blue growth and pigment diffuses into averageMacConkey agarNo GrowthBlood agarlarge brown coloniesSample location No.4Nutrient agarWhite, smooth, round coloniesMacConkey agarNo GrowthBlood agarNo GrowthSample location No.5Nu trient agarNo GrowthMacConkey agarNo GrowthBlood agarNo GrowthSample location No.6Nutrient agarCircular, smooth, opaque coloniesMacConkey agarNo GrowthBlood agarswarming motilitySample location No.7Nutrient agarNo GrowthMacConkey agarNo GrowthBlood agarNo GrowthSample location No.8Nutrient agarsmooth, translucent large colonies , greenish blue growth and pigment diffuses into mediumMacConkey agarslight pink coloniesBlood agarlarge brownish coloniesSample location No.9Nutrient agarsmooth, translucent large colonies , greenish blue growth and pigment diffuses into mediumMacConkey agarslight pink coloniesBlood agarNo GrowthSample location No.10Nutrient agarNo GrowthMacConkey agarNo GrowthBlood agarNo GrowthTable 9 shows the colony descriptions result of the microorganisms isolated from the wood surface. Six of ten wood surfaces remained contaminated with bacteria before and after cleaning.Table 10 The colony count of the microbial survival on wood surfaceSample No.Serial ten-fold dilu tions in deionised water diluentscolony count (CFU ml-1) before cleaningcolony count (CFU ml-1) After cleaningSample No.16.4 x 102Bacteria Not DetectedSample No.35.3 x 102Bacteria Not DetectedSample No.42.7 x 102Bacteria Not DetectedSample No.6TMTCTMTCSample No.81.67 x 1032.9 x 102Sample No.99.3 x 1023.6 x 102Table 10 shows the result of the colony count obtained before and after cleaning stage of wood surface.Table 11 Gram stain result of the microbial survival on wood surfaceSample No.1Gram stain resultGram negative, rod shapeSample No.3Gram stain resultGram negative, rod shapeSample No.4Gram stain resultGram negative, rod shapeSample No.6Gram stain resultGram negative, rod shapeSample No.8Gram stain resultGram negative, rod shapeSample No.9Gram stain resultGram negative, rod shapeTable 11 show the result of the Gram stain of bacteria that was isolated from the wood surface before and after the cleaning stage.Table 12 The Identification of bacteria by phoenix machine that survived on wood surface before the cleaning stageSample No.1Sample No. In phoenix machine86 woodName of Bacteria detected before cleaningAcinetobacter baumanniiName of Bacteria detected after cleaningNot DetectedSample No.3Sample No. In phoenix machine301 woodName of Bacteria detected before cleaningPseudomonas sppName of Bacteria detected after cleaningNot DetectedSample No.4Sample No. In phoenix machine326 woodName of Bacteria detected before cleaningEnterobacter hafinae alveiName of Bacteria detected after cleaningNot DetectedSample No.6Sample No. In phoenix machine342 woodName of Bacteria detected before cleaningProteus vulgarisName of Bacteria detected after cleaningProteus vulgarisSample No.8Sample No. In phoenix machine369 woodName of Bacteria detected before cleaningPseudomonas aeruginosaName of Bacteria detected after cleaningPseudomonas aeruginosaSample No.9Sample No. In phoenix machine385 woodName of Bacteria detected before cleaningPseudomonas aeruginosaName of Bacteria detecte d after cleaningPseudomonas aeruginosaTable 12 shows the result of bacterial identification that obtained by phoenix machine which was isolated from wood surface before and after the cleaning stage.ControlTable 13 extract of Staph aureus and E.coli on stainless steel surfacesStaphylococcus aureusEscherichia coliTime of swab process after contaminationHigh contamination level (106 colony)CFU/100 cm2Low contamination level (103 colony)CFU/100 cm2High contamination level (106 colony)CFU/100 cm2Low contamination level (103 colony)CFU/100 cm2After 15 minute2.0 x 1071.0 x 1041.6 x 1075.2 x 103After 2 Hours1.73 x 1079.1 x 1038.3 x 1061.8 x 103After 6 Hours1.3 x 1073.8 x 1032.1 x 106No growthAfter 12 Hours5.8 x 106No GrowthNo GrowthNo growthAfter 24 HoursNo growthNo GrowthNo GrowthNo growthTable 13 shows the survival of Staphylococcus aureus and Escherichia coli on stainless steel surfaces at room temperature (25oC) for 24 hours at two contamination level high contamination level of (106 c olony CFU/100 cm2) and Low contamination level (103 colony CFU/100 cm2).DiscussionSampling food contact surfaces is a complex problem, and the results depend on many factors, including the type of surface, the cleaning solution, the sources of contamination, and the temperature. The accuracy and reproducibility of all sampling methods are reduced when the numbers of bacteria on the surface are low. Some differences between methods are probably due to an uneven distribution of bacteria on the surface. The type of surface markedly influenced the cleaning results. For this study, nineteen selected set forth were tested/studied (Ten replicate surfaces were tested stainless steel, marble and wood, with adjacent areas being sampled before and after cleaning). The results of these studies indicate that three of ten stainless steel surfaces were contaminated before cleaning the surfaces and no surface was contaminated after cleaning, which means that stainless steel surfaces were more goo d cleaned. Furthermore, three out of ten marble surfaces were contaminated before cleaning and one surface was contaminated after cleaning the surfaces, which means marble surfaces were easily cleaned but using the wrong cleaning products and the wrong cleaning techniques can damage the marble because marble is a calcium-based natural stone which is super sensitive to acidic materials (Marble Institute of America, 2012). Stainless steel resists impact damage but is vulnerable to corrosion, while marble surfaces are prone to deterioration and may develop surface cracks where bacteria can accumulate (Leclercq and Lalande, 1994). Wood surfaces were particularly diffi