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Microbiology Assignment: Microbial Analysis of Raw Fish

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Added on  2020-05-28

Microbiology Assignment: Microbial Analysis of Raw Fish

   Added on 2020-05-28

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Laboratory Report Diary1Laboratory Report DiaryBy NameCourse lab report InstructorInstitutionLocationDate
Microbiology Assignment: Microbial Analysis of Raw Fish_1
Laboratory Report Diary2Laboratory Report DiaryExperiment 1: Microbial Analysis of Raw Fish – In DuplicateAimTo examine the micro flora of fish samplesIntroductionFish consumption has been going on for so long in various cultures around the world. There are several bacteria associated with the various fish types and a lot of research has been going on (Asakura et al, 2014). Understanding the microbial of fish is very critical in improving the sanitation levels in growing fish, preparation, packaging and consuming of fish. We usually find fish in cold environments that may be polluted by soil particles or even faeces (Clarke et al, 2018). It is very obvious for someone to expect finding psychotropic organisms as well as halophiles and coliforms such as the pseudomonas.Microbiological analysis involves the identification of total viable aerobic count by standard plate count method and probable number method was used for enumeration of fecal andtotal coliform. Salmonellaspp. andVibrio choleraeare some of the most common bacteria associated with fish-related infection. Fish is among the most preferred foods due to the high nutritional value but contamination during handling, transport and processing is a big challenge.The higher nutrition value of fish has made them a key export earning commodity in several countries around the world. The various types of fish have a high protein content, low amount of carbohydrates and zero unhealthy fats. At the various stages of handling, transportation and processing the fish may be contaminated by pathogens that cause foodborne infections. The contamination may be caused by the raw material, processing tools or leakages. We used nutrient agar and PSB agar as a medium to support the growth and development of a broad range of microbial organisms. The nutrient agar is constituted by peptone, beef or yeast extracts, sodium chloride and distilled water. The purpose of the peptone in the medium is to provide organic nitrogen while the water-soluble content of yeast or beef extracts provides carbohydrates, nitrogen, vitamins and salts. The 0.5 % sodium in the medium contributes to the mixture to have similar proportions to those in the cytoplasm of majority of the microbial organisms. The distilled water provides a transport medium for various substances in the agar. The pH of the medium is usually adjusted and the nutrient agar is sterilized before use.
Microbiology Assignment: Microbial Analysis of Raw Fish_2
Laboratory Report Diary3Provided SamplesWhole fish-oily 1 sampleSample of white fish – 2 samplesRaw king prawn- 2samplesMethod1.Place the stomacher bag onto the balance and tare the weight.2.Sterilise the scalpel and forceps by dipping them in methylated spirits and flaming carefullyto burn off the excess.3.Weigh accurately, using an aseptic technique, 10 grams of food into the stomacher bag. Donot handle the food, bag or implements.4.Aseptically add 90 mls of MRD to the stomacher bag.5.Place in the stomacher and stomach for 30 to 60 seconds.6.Sit the bag in a beaker for use.This is now a 1 in 10 (10-1) dilution of the sample- repeat for all three sandwiches.Proceed to make two further dilutions of each using the standard technique. Dilutions will be 10-2and 10-3. Make these with 1ml of the 10-1 and 9ml of MRD. Make sure that all the bottles arelabeled correctly.Label 12 TSA plates with sandwich name, dilution, group initials, temperature of incubation have2 plates for each. Repeat this for Baird Parker, MEA and KAA. Make up the XLD as per theinstructions on packaging and pour 12 plates.Each group will be allocated a sandwich type and dilution pour 8 plates of VRBGA, 4 plates for37°C and 4 plates at 44°C.Once you have labelled and poured plates pipette sample (0.5ml) onto plates in duplicate andincubate at recommended temperatures.Results
Microbiology Assignment: Microbial Analysis of Raw Fish_3
Laboratory Report Diary4Table 1.1Showing results of templateNutrient agarNutrient agar + saltPSBagarfish type10-110-210-3fish type10-110-210-3fish type10-110-210-3oily group185%70%70%oily group190%95%>300oily group160%>30028975%75%80%70%95%>30055%>300>300oily group2>300>300>300oily group2>300>300>300 (2Y)oily group 2>30018044 (1 O)>300>300>300>300>300>300 (3Y)>30022060 (6 O)oily group3>300>300>300oily group3>300>300>300oily group 3>30014440>300>300>300>300>300>300>30011132oily group490%80%95%oily group480%97%100%oily group 465%60%22095%75%90%95%90%100%70%60%60%whitefish group180%85%80%whitefish group185%65%>300white fish group1>300103685%95%508560>30>33919
Microbiology Assignment: Microbial Analysis of Raw Fish_4
Laboratory Report Diary5%%%000whitefish group2>300>300>300whitefish group2>300>300>300white fish group 2>300459>300>300>300>300>300>300>3006211White fishgroup3>30080%89White fishgroup3>300>300206White fish group 3>300>30027>30090%135>300>300>300>300>30070White fishgroup480%90%90%White fishgroup495%>300>300White fish group 470%50%60%95%70%(1 YELLOW)80%80%85%70%50%50%50%prawn group 185%90%>300prawn group 190%80%>300prawn group 190%811185%90%>30050%95%>30055%5715prawn group2>300>300>300 ( y-4,p-6)prawn group2>300>300>300prawn group 22406024,all p
Microbiology Assignment: Microbial Analysis of Raw Fish_5
Laboratory Report Diary6>300>300>300>300>3002521603014,all pprawn group395%95%95%prawn group395%>300>300prawn group 3>3001301080%95%95%95%>300>300>30011823prawn group4>300>300>300prawn group4>300>300>300(28YELLOW)prawn group 41558129>300>300>300>300>300>300(2 YELLOW)>3008310Y= yellowp= Pinkc= CreamO = orangePurple represent positive while pink represent negative results for the presence of the various bacteria.1. Micrococcus aurentiaca- purple2. Micrococcus roseus – purple3. Pseudomonas fluorescenes – pink
Microbiology Assignment: Microbial Analysis of Raw Fish_6

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