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ThesisItem Open Access Evaluation of bacteriological quality of beef carcasses in meat processing plant(Department of Veterinary Public Health, College of Veterinary and Animal Sciences, Mannuthy, 2003) Sethulekshmi, C; KAU; Nanu, EDuring the present study, 40 beef carcasses were randomly selected from a meat processing plant located at Kochi in Kerala. The plant procures beef carcasses from two slaughtering units, viz., Source A and B, located in Tamil Nadu. From each carcass surface 500-cm2 area was swabbed which consisted of 100 cm2 each from neck, brisket, loin, flank and outer round. The samples from each carcass were examined for the bacterial quality by estimating the total viable count (TVC), coliforms count (CC), Escherichia coli count (ECC) and faecal streptococcal count (FSC). All samples were also subjected to the isolation and identification of Escherichia coli, Staphylococcus aureus, Salmonella and Listeria monocytogenes. The samples of air, water, equipment and hand wash of personnel were also collected and estimated the various bacterial loads of these samples. Analysis of variance test of the data did not reveal significant difference between the mean total viable count of the samples from two sources. The samples had an overall mean total viable count of 7.40 ± 0.17 10glO cfu/cm/. The mean count of samples from source B was slightly higher than that from source A. The count of the samples belonging to source A ranged from 106 to 109 cfu/cm2 while the count of the samples from source B varied between 106 and 108 cfu/cm/. Of the 40 carcass samples examined, 45 per cent had count at the level of 106 cfu/crrr', The counts in 30 per cent and 22.5 per cent were at the level of 108 cfulcm2 and 107 cfu/cnr', resp~ctively. Analysis of variance' test of the data revealed a significant (P<0.05) difference between the mean coliforms count of the samples from the two sources. The samples from source A had a higher mean count. The overall mean coliforms count of the samples was 3.41 ± 0.13 10glO cfu/cm". The count of the samples from both the sources varied from 102 to 104 cfu/cm/. The count in 21 (52.5 per cent) carcass samples was at the level of 103 cfu/crn", In 17.5 per cent carcasses the count was at the level of 104 cfu/crrr' and in 30 per cent carcass samples the count was at the level of 102 cfu/crrr'. Analysis of variance test of the Escherichia coli count revealed a significant (P<0.05) difference between the mean count of samples from the two sources. The samples belonging to source A had a higher mean count. The overall mean Escherichia coli count of the samples was 1.83 ± 0.22 10glO cfu/crrr'. The Escherichia coli count of the samples from both the sources varied from 101 to 103 cfu/cm2. The count in 16 (40 per cent) of carcass samples was at the level of 102 cfu/cm", In 17.5 per cent samples each had count at the levels of 101 and 103 cfu/cm", Analysis of variance test of the faecal streptococcal count revealed significant (P<0.05) difference between the mean counts of samples from the two sources. Source A had higher mean count. The overall mean count of samples was 3.27 ± 0.10 10glO cfu/cm". The count on the carcasses from the source A ranged between 102 to 104 cfu/crrr' whereas the count on the carcasses belonging to source B varied between 102 to 103 cfu/crrr'. Out of 40 carcasses, 18 (45 per cent) had count at the level of 103 cfu/crrr'. The counts on 40 and 15 per cent of the carcasses were at the levels of 102 to 104 cfu/cm/, respectively. A significant (P<0.05) positive correlation was observed between the mean CC and FSC of the carcasses belonging to source A. The association between the mean TVC and FSC in source B was significant (P<0.05). Escherichia coli was isolated from 10 carcasses belonging to source A and 5 carcasses from source B. Out of the 15 isolates, 14 were serotyped and were grouped under nine serotypes and one isolate was untypeable. The serotype 0157 was isolated from two of the carcass samples belonging to source A. Four isolates from this source belonged to serotype 036. The serotypes 036, 0156, 0157 and 0172 were isolated only from the samples obtained from the source A. The serotype 08 was isolated from both the sources. However, the serotypes 013,065,069 and 075 were isolated only from samples of source B. Staphylococcus aureus was isolated from two (5 per cent) carcasses belonging to source A and one (2.5 per cent) of the carcasses belonging to the source B. Of-the 40 carcass samples tested, salmonellae were isolated from one sample each from the source A and B. Listeria monocytogenes could not be isolated from any of the samples belonging to both the sources. The mean total viable counts on meat-cutting board and meat-cutting table were 4.94 ± 0.87 and 4.28 ± 0.87 10glO cfu/cm/, respectively. The mean coliforms count on the former was 1.24 ± 0.94 10glO cfu/crrr' and the latter was at the level of 1.26 ± 0.83 10glO cfu/crrr'. The mean faecal streptococcal count was at the level of 1.38 and 1.29 10glO cfulcm2 on meat cutting board and meat cutting table, respectively. Ice samples had a mean total viable count of 3.20 ± 0.11 10glO cfu/ml. The coli forms count in ice, pond, and tap water were 2.30 ± 0.08, 1.39 ± 0.77 and 0.50 ± 0.21 10glO cfu/ml, respectively. The mean total viable count, coliforms count, Escherichia coli count and faecal streptococcal count observed per ml of the hand wash of the personnel engaged in various operations were 4.96 ± 0.82, 1.26 ± 0.78, 0.80 ± 0.24 and 1.48 ± 0.77 IOglO cfu/ml, respectively. The mean bacterial load in the air samples of slaughter hall and chilling room obtained in the present study was 100.7 ± 8.17 and 8.75 ± 1.19 cfu/min, respectively.ThesisItem Open Access Evaluation of bacteriological quality of pork carcasses in a processing plant(Department of Veterinary Public Health, College of Veterinary and Animal Sciences, Mannuthy, 2003) Shiny John; KAU; Nanu, EDuring the present study, 25 pork carcasses were randomly selected from the dressing line of a pork processing plant, in order to evaluate the hygienic status of the carcasses produced in the plant. From each carcass, after evisceration and also after final washing, 500 Clll2 area was swabbed, which consisted of 100 cm2 each from jowl, shoulder, bacon, loin and ham areas. Samples collected, after evisceration were pooled into 500 1111 diluent, which formed the initial test samples. Similarly, the initial test sample was also prepared with the samples collected from the finally washed carcasses. This sample was tested to evaluate the bacterial quality of carcasses by estimating total viable count, coliforms count, Escherichia coli count and faecal streptocoecal count. The sample was also used for the isolation and identification Escherichia coli, Staphylococcus aureus, Salmonella and Listeria monocytogenes. Samples from environment, processing equipment, hand wash of personnel, scalding tank water and HOPE pouches were also tested to estimate the bacterial load. Analysis of variance test revealed signi ficunt (Peviscerated and finally washed carcasses. The mean count in the former and latter groups or carcasses was 5.14 L O.I() and 5.31 :L 0.16 loglo cfu/cm", respectively. In ()4,20 and le) per cent or the eviscerated carcasses the count was at levels 105, 104 and 10.1 cfu/cm", respectively. III tile latter group or carcasses, eight, 56,32 and four per cent had the count at the level of 10(1, 105, 104 and io' cfu/crn", respectively. The mean coli forms count of eviscerated carcasses was 1.89 ± 0.17 10g\O cfu/cm ' and the count in the finally washed carcasses was 1.99 ± 0.23 10glO cfu/crn". night and 24 per cent ni' samples bclongiru; to both groups had tile count at the level of 102 cfu/cm". The count ill 52 ami 24 per cent or eviscerated and finally washed carcass samples was at the level or lolcru/C\\l2. Eviscerated carcasses had a mean Escherichia coli count of 1.19 ± 0.08 loglo cfu/cm ' and the count ill finnl ly washed carcasses was 1.29 :I: 0.12 loglo cfu/cm", The organism was not detected in RO and R4 per cent or eviscerated and finally washed carcasses, respectively. Tile count in I () and four per cent of the former group or carcasses was at levels I {)2 and I ()I Cl'U/CI1l2. respectively. In eight per cent each of finally washed carcasses, the count was at the level of 102 and 101 cfu/cm2. '~he eviscerated and finally wash cd carcasses had a mean faecal streptococcal count of 3.19 ± 0.20 and 3.28 ±O.20 loglo cfu/cm, respectively. The count on 12 per cent of carcasses in each of the above groups, did not reveal the organism. However, in both the groups 01' carcasses, 20 pCI' cent or samples each had the count at 103 cfu/crrr'. The count in 52 pCI' cent of the eviscerated and 60 pCI' cent of the finally washed carcasses was ut the level or 102 cf'U/CIl12. The count at the level of 101 cfu/cm2 was observed in I () pCI' cent or the eviscerated and eight pCI' cent of the finally washed carcasses. Analysis 01' the data revealed positive and significant (P<0.05) association between CC and ECC in eviscerated and finally washed carcasses. However, a negative but signi ficant (P 0.05) correlation was observed between TVC and CC and TVC and ECC in the finally washed carcasses. Escherichia coli was isolated from 20 per cent of eviscerated carcasses and 16 per cent of finally washed carcasses. Out of 18 isolates recovered from both the groups, 15 fell into 12 scrotypcs and three were untypablc. The serotypes include 05,08,011, 025,060,064,078,088, OlOl, 0119, 0123 and 0140. Staphylococcus aureus was isolated from eight and 24 per cent of samples belonging to eviscerated and finally washed carcasses, respectively. None of the carcass samples in both the groups revealed the presence of Salmonella and Listeria monocytogenes. Air samples at the evisceration area had the highest bacterial count and the lowest was observed at the chilling room. Pond water samples had the highest mean total viable count and coli forms population was seen highest in scalding tank water. Escherichia coli count was highest in hand washing of personnel. None of the pond and tank water samples revealed presence of the organism. Samples collected from the bell semper had the highest mean total viable count and least in packaging material. Samples obtained from carcass splitter had the highest coliforms count. None of the processing cquipmcnts revealed the presence of Escherichia coli. Cutting board samples showed the highest faecal streptococcal, count.ThesisItem Open Access Effect of refrigeration on the quality of beef frankfurter and chicken pepperoni(Department of Veterinary Public Health, College of Veterinary and Animal Sciences, Mannuthy, 2004) Ambili, V S; KAU; Latha, CThe present study was conducted to assess the microbial, physico- chemical and organoleptic qualities of beef frankfurter and chicken pepperoni at chilled and frozen storage. Effect of storage on these products was studied by estimating various microbial counts, assessing the presence of certain pathogenic and spoilage bacteria and studying the changes in pH and TBARS number and organoleptic qualities like color, odor and presence of sliminess. In chilled samples (4-7°C) the mean total viable count, faecal streptococcal count, psychrotrophic count and yeast and mold count were found to increase significantly as storage period progressed. In both the products, coliforms reached a detectable level by second day of chilled storage and thereafter the count increased. E. coli were detected only from samples of chilled beef frankfurter from fourth day onwards and the count remained at 101 cfu/g level. Aeromonas hydrophila, A. sobria and A. caviae were the three species of Aeromonas isolated from the chilled samples of both the products. Hemolytic and hemagglutination assays of these isolates were also carried out which is indicative of enteropathogenic effects. Escherichia coli were isolated from beef frankfurter samples. Among the isolates 84.62 per cent belonged to the serotype O2 ( Enterohaemorrhagic E. coli.). Salomonellae could not be detected from any of the samples. A number of samples revealed the presence of Pseudomonas aeruginosa. Important species of lactobacilli isolated were Lactobacillus brevis, Lactobacillus curvatus, Lactobacillus fermentum and Lactobacillus sake. The mean pH and TBARS values were increased during chilled storage, indicating the progress of development of acidity and rancidity. Color and odor scores gradually increased from fourth day onwards and slight discoloration was noticed on 10th day in both the products. Surface slime was developed on fourth day in beef frankfurter samples and from sixth day onwards in chicken pepperoni samples. Thus, the shelf life was found to be four days for beef frankfurter and less than six days for chicken pepperoni stored at 4-7° C. When samples were stored at –20°C, it was observed that mean total viable counts of fresh and frozen beef frankfurter samples did not differ significantly. Frozen samples of chicken pepperoni had the total viable count significantly (P<0.05) lower than that of fresh samples. Aeromonas hydrophila, A. sobria and A. caviae were isolated from frozen samples of both the products. Many of the isolates were hemolytic and hemagglutinating. Pseudomonas aeruginosa were also detected. E. coli , salmonellae, and lactobacilli were not isolated from any of the frozen samples. Frozen sausage samples had lower mean pH values when compared to fresh samples and mean TBARS values were found to decrease gradually during the frozen storage. Color and odor scores remained the same during frozen storage and slime formation was not observed in frozen samples. Study revealed that frozen samples of both products had a shelf-life of 90 days. In order to identify various critical points of bacterial contamination, samples of air, water, rinse samples from equipment, hand washing of personnel in the processing line and packaging material were examined for their hygienic quality. The mean total viable count and yeast and mold count of air samples were found to increase after processing. Among the water samples, the high microbial count was recorded for hand washings, reflecting unsanitary working practices. Among the equipment, sausage filler was found to contribute maximum to the total microbial load of the product. Among the raw ingredients, samples of beef used for preparation of beef frankfurter and samples of pork used for chicken pepperoni were found to possess high bacterial load. Coliforms were present at 2 log cfu/g level in all the ingredients. Faecal streptococci were detected in all the ingredients except beef. E. coli were present only in samples of spices. Study reflects the importance of quality assurance during every step of preparation of ready-to-cook meat products to avoid the early spoilage and to safe guard consumer health. Presence of pathogenic organisms in these products is of great public health significance as improper cooking can cause outbreaks of food borne diseases.