Total Mesophilic Bacterial Counts Research Articles

Examining the Effect of Agrochemicals on Soil Microbiological Activity, Micronutrient Availability, and Uptake by Maize (Zea mays L.) Plants

Agricultural practices profoundly influence soil microbial populations and physicochemical properties, vital for crop growth and quality. This study aims to explore the impact of diverse agrochemical applications on soil microbial dynamics, physicochemical properties, and maize yield and proximate properties. Topsoil samples, collected at depths of 1 to 15 cm, were transported to Jimma University for maize cultivation. Over 120 days, soil and maize samples were collected at specified intervals for analysis, including soil pH, microbial populations, and nutrient content. Statistical analysis using one-way ANOVA (p < 0.05) was conducted. Soil bacterial and fungal populations were measured on days 5, 10, 20, 40, 80, and 120. The highest total mesophilic bacterial count (TMBC) was in compost-treated pots (G) and the lowest in those receiving macronutrient fertilizers and glyphosates (B). The highest total mesophilic fungal count (TMFC) was in pots with glyphosates and compost (F), and the lowest was in pots treated with macronutrient fertilizers and glyphosates (B). Pots treated with macronutrient fertilizers and glyphosates (B), macronutrient fertilizers (A), and micronutrient fertilizers (C) showed the lowest Fe and Zn levels. Maize in pots treated with macronutrient fertilizer combined with glyphosate (B) exhibited the lowest protein, fats, and carbohydrates. Notably, compost-treated soils showed the highest bacterial and fungal counts, Fe, and Zn concentrations, while micro-mineral fertilizer combined with glyphosate (B) depleted the soil. Agrochemical treatments negatively affected maize yield quality, indicating complex treatment-related changes in soil parameters.

Use of Ozone in Veterinary Dentistry as an Alternative to Conventional Antibiotics and Antiseptics.

This paper aims to assess the disinfecting capacity of a double-distilled ozonated water solution as an alternative to common antibiotic and antiseptic devices. Seventy-five dogs were subjected to the surgical procedures of scaling and dental extraction and included in three study groups: Group 1 subjected to antibiotic pre-treatment (association amoxicillin + clavulanic acid and ampicillin + metronidazole) and disinfection with chlorhexidine, and Group 2 and 3 devoid of preventive anti-microbial treatment in which disinfection was performed, respectively, with ozonated water and chlorhexidine. Sampling by bacteriological buffer was carried out to evaluate the bacterial count in the oral cavity. The analysis of the samples determined the total mesophilic bacterial count by seeding on the culture medium via the inclusion of PCA (Plate Count Agar). The results highlighted the anti-bacterial efficacy of intra-operative ozone as an alternative to pre-surgical antibiotic treatment.

Effects of Modified Atmosphere Packaging with Varied CO2 and O2 Concentrations on the Texture, Protein, and Odor Characteristics of Salmon during Cold Storage.

The effect of gas ratio on the growth of bacteria has been well demonstrated, but some adverse effects of modified atmosphere packaging (MAP) on seafoods have also been found. To provide a better understanding of the effects of CO2 and O2 concentrations (CO2 from 40% to 100% and O2 from 0% to 30%) in MAP on the texture and protein contents and odor characteristics of salmon during cold storage, the physiochemical, microbial, and odor indicators were compared with those without treatment (CK). Generally, MAP treatments hindered the increase of microbial counts, total volatile basic nitrogen, and TCA-soluble peptides, and decreased the water-holding capacity, hardness, springiness, and sarcoplasmic and myofibrillar protein contents. The results also indicated that 60%CO2/10%O2/30%N2 was optimal and decreased the total mesophilic bacterial counts by 2.8 log cfu/g in comparison with CK on day 12. In agreement, the concentration of CO2 of 60% showed the lowest myofibrillar protein degradation, and less subsequent loss of hardness. The electronic nose characteristics analysis indicated that 60%CO2/20%O2/20%N2 and 60%CO2/10%O2/30%N2 had the best effect to maintain the original odor profiles of salmon. The correlation analysis demonstrated that microbial growth had a strong relationship with myofibrillar and sarcoplasmic protein content. It can be concluded that 60%CO2/10%O2/30%N2 displayed the best effect to achieve the goal of preventing protein degradation and odor changes in salmon fillets.

Survival of Naturally Contaminating Listeria monocytogenes in Commercial Mediterranean-Style Dry Fermented Sausages during Storage

The aim of the present study was the determination of Listeria monocytogenes, competitive microbiota, microbial hygiene indicators, and physicochemical parameters in the typical Mediterranean-style fermented sausages Salsiccia Sarda. A batch of Salsiccia Sarda (25 samples) naturally contaminated by L. monocytogenes and vacuum packaged after 24 days of ripening was included in the study. Fifteen samples stored at 8°C were analyzed after 13 days, after 90 days, and at the end of shelf life (after 180 days from vacuum packaging). Ten vacuum-packaged samples were stored at 12°C in a domestic fridge simulating temperature abuse and were evaluated at the end of the shelf life. Samples were subjected to physicochemical analysis (pH and water activity) and investigated for the presence and enumeration of L. monocytogenes. Competitive microbiota, lactic acid bacteria, coagulase-negative staphylococci, and microbial hygiene indicators (total mesophilic bacterial counts, Enterobacteriaceae, Enterococcuss spp., and Staphylococcus aureus) were determined in all the samples. Although a decreasing trend in L. monocytogenes prevalence was observed through the shelf life, the detection of this pathogen in fermented sausages confirms its ability to overcome hurdles of the manufacturing process. The results highlight the importance of the careful evaluation of the Salsiccia Sarda production process by food business operators to maintain unfavorable conditions for the growth of L. monocytogenes.

Optimization of traditional starter culture and African locust beans for daddawa production using Response Surface Methodology (RSM)

“Daddawa” is a traditional condiment that is produced by the fermentation of African locust beans (Parkia biglobosa). It is a popular food condiment and economical method of food preservation specifically in the West and Central African region. The traditional starter culture used was isolated and identified using biochemical methods. Optimization of fermentation conditions of the starter culture and the locust beans was carried out using a central composite design of response surface methodology (RSM). The fermentation was considered at 40°C for 72 h. Bacteria suspected to be Bacillus subtilis, other Bacillus species, Staphylococcus aureus and other Staphylococcus species were isolated from the traditional starter culture while Bacillus subtilis and other Bacillus species, were further isolated from the optimized product. Locust bean fermentation was found to be optimum at 0.12 g of the starter culture and 50 g of locust beans. The results illustrate 0.994 mg/ml concentration of amino acid (L –Valine) and 8.15 x 106 cfu/ml total mesophilic bacterial count at the optimum parameters. This result revealed that Bacillus species, most importantly Bacillus subtilis are the vibrant bacteria involved in the fermentation process since it was significantly found in the end product.

Hygiene and Safety of Hard Cheese Made from Raw Cows' Milk.

Simple SummaryRaw cheeses have gained the preference of some consumers because of their intense and stronger taste compared with that of pasteurised cheeses. The pasteurization of raw milk causes the inactivation of the pathogenic and beneficial microorganisms of milk and of enzymes such as proteases and lipases which play a significant role in enhancing the unique flavour of raw cheeses. This study was conducted to evaluate the microbiological status of cheese made from unpasteurized cows’ milk, to examine the safety of the cheese and to observe the changes that occurred in its microbial community during ripening and storage. The microbiological quality of raw milk was found generally good and was improved throughout the experiments. For the cheese samples, a small increase in the prevalence of indicator microorganisms in curd and cheese samples was observed for the first few days, followed by a relatively stable condition as manufacturing proceeded and throughout the ripening of the final product. The outcome of our study was that the use of good-quality raw milk under sanitary conditions, the application of good manufacturing practices and a maturation period in a controlled environment were found to be the necessary prerequisites for the production of safe raw cheese products.This study was conducted to evaluate the microbiological status of cheese made from unpasteurized cows’ milk, to examine the safety of the cheese and to observe the changes that occurred in its microbial community during ripening and storage. Furthermore, the pH, the moisture and salt concentration were also monitored throughout processing, ripening and storage. Seven cheesemaking trials took place along with the microbiological and physicochemical analysis of the milk, curd and cheese produced. The milk used for the cheesemaking, two curd samples before the heating and two after the heating, two cheese samples at days 3, 7, 15, 30, 60 and 90 were subjected to microbiological analysis for total mesophilic bacterial count (for milk only), Enterobacteriaceae, E. coli, Staphylococcus, Salmonella, Listeria, and Clostridium. The microbiological quality of raw milk was found to be good. It was initially slightly above the EU limit but improvements associated with farm biosecurity and milking equipment hygiene led to a significantly improved milk quality. A small increase in the prevalence of indicator microorganisms in curd and cheese samples was observed for the first few days, followed by a relatively stable condition as manufacturing proceeded and throughout the ripening of the final product. In two cheesemaking trials, Clostridium perfringens and Salmonella spp. were detected, the first originating from the milk and the second from the environment. The use of good-quality raw milk under sanitary conditions, the application of good manufacturing practices and a maturation period in a controlled environment were found to be the necessary prerequisites for the production of safe raw cheese products.

Influence of corn starch based bio-active edible coating containing fumaric acid on the lipid quality and microbial shelf life of silver pomfret fish steaks stored at 4°C.

The present study aimed at assessing the impact of addition of fumaric acid (0.5%), as an active agent, in a corn starch (2%) based edible coating, on the lipid quality and microbial shelf life of silver pomfret (Pampus argenteus) fish steaks stored at 4°C. Treating fish steaks with FA resulted in a bacteriostatic effect leading to reduced counts of total mesophilic and psychrotrophic bacteria, H2S producing bacteria and Pseudomonas spp. The total mesophilic bacterial count of uncoated control sample exceeded the permissible limit of 7 log cfu g-1 on 6th day and had the lowest microbial shelf life. FA incorporation in the CS coating improved the microbial stability of fish steaks resulting in a shelf life of 15days. The outcomes of the study suggest that CS based coating is beneficial in delaying lipid oxidation as displayed by the lower TBA and PV values while FA is an effective agent for further increasing the preservative action of CS coating by significantly inhibiting microbial growth as well as lipid quality deterioration, which could be exploited by the seafood industry as an active packaging component.

New application of microbial l-glutaminase as a flavor enhancing agent in beef burgers

L‑glutaminase (L‑glutamine amidohydrolase EC3.5.1.2) is the key enzyme in enhancing the taste and aroma of oriental fermented foods by increasing their glutamic acid content and as a result imparting a palatable taste. Beef burgers were prepared using different levels of the partially purified L- glutaminase (2.0 to10.0 U/100 g) prepared from Aspergillus oryzae NRRL 32567. Beef burgers treated with 6.0 U/100g and the others treated with monosodium glutamate (5000 ppm) were chemically, sensory and microbiologically evaluated and compared to untreated control during frozen storage at –18 ºC for 3 months. Treatment with L‑glutaminase (6 U/100g) resulted in an increase of 443% in glutamic acid and a reduction of 63% in glutamine contents resulting in an enhanced preferable taste and odor of the prepared beef burgers. Burgers treated with 6.0 U/100g exhibited the best odor, texture, taste and overall quality scores when compared to the untreated control and samples treated with monosodium glutamate (5000 ppm). During the frozen storage of all samples, an expected slight, but significant (p≤0.05), increase in the total mesophilic bacterial count was evident and such increase was quite acceptable since numbers did not exceed the limit of 5.7x103 cfu/g. Similarly, the total psychrotrophs did not exceed 3.7x102 cfu/g.

Bacterial contaminants of new disposable ready-to-use plastic cups sold within Gombe Metropolis, Gombe State, Nigeria

Background: Disposable cups are usually used for drinking without any form of pre-cleaning, this has the potential to expose individuals to pathogenic microorganisms, and unfortunately this issue has not been investigated in Gombe metropolis, hence, this study aimed to investigate the bacteriological aspect of the problem and to reduce the existing knowledge gap regarding this problem. Methods: Thirty samples were collected using simple random sampling from two different markets, then swab sticks pre-moistened with peptone water were used to swab the inner portions of the cups, put in sterile distilled water, serially diluted, inoculated on nutrient agar, and incubated. Identification of the isolates were done using their physical and biochemical characteristics, antibiotic susceptibility tests were done using disc diffusion method and interpreted using Clinical and Laboratory Standards Institute (CLSI) guidelines. Results: The total mesophilic bacterial counts ranged from 3.0×105 to 9.9×105 CFU/ml. These isolates were identified and tested for their sensitivity to some antibiotics which revealed that Escherichia coli (E.coli ) were sensitive to augmentin, ampicillin, and ciprofloxacin, but intermediately resistant to chloramphenicol, Staphylococcus aureus (S. aureus) were sensitive to ciprofloxacin and augmentin, intermediately resistant to chloramphenicol, and resistant to ampicillin. Bacillus spp were sensitive to augmentin, ciprofloxacin, chloramphenicol and ampicillin, while Pseudomonas aeruginosa (P.aeruginosa) were sensitive to ciprofloxacin, augmentin, and chloramphenicol, but intermediately resistant to ampicillin. Conclusion: These new disposable ready-to-use cups harbored some potentially pathogenic bacteria which were resistant to some antibiotics. It is therefore recommended that pre-use hygiene practices should be done on these cups prior to use to avert the health effects of consuming these bacteria.

Effects of “fresh mechanically deboned meat” inclusion on nutritional value, palatability, shelf-life microbiological risk and digestibility in dry dog food

Fresh mechanically deboned meat (MDM) is usually claimed as high-quality ingredient on dry pet food recipes and this aspect may positively influence consumer choice. It is important to determine the scientifically sustainability of this claim and to assess the microbiological safety of MDM inclusion in dry pet food. Objectives were: 1) to evaluate the effect of inclusion of MDM in dry dog food on fatty acid profile and in vivo and in vitro digestibility, proposing a new system (DaisyII Incubator) to measure the in vitro digestibility for dogs; 2) to compare palatability of dry dog food containing MDM with dry dog food in which meat by-products (MBP) are the only animal protein sources; 3) to determine, whether or not, the inclusion of that ingredient changes the microbiology and the storage quality. Results indicated that MDM product was characterized by significant higher nutritional value in terms of fatty acids profile, in vitro digestibility (HV-IVD method) and lower palatability than the MBP product. Microbiological risk assessment showed no microbiological hazards for either product. After 6-months storage, the total mesophilic bacterial count ranged between 1.77 and 2.09 log CFU/g feed, while polyamine values were higher in the MDM (0.37 g/kg) than in the MBP (0.27 g/kg). The DaisyII Incubator was found to be a valid instrument for studying in vitro digestibility also for dogs, providing data simply, quickly, with less variability and costs than in vivo trials. In conclusion, MDM inclusion in dry dog food is microbiologically safe and it can improve its nutritional quality, at the expense of a reduced palatability. The higher polyamine levels fount in MDM-enriched petfood after 6-months storage, however, may represent a possible hazard, and further studies are still warranted.

Quality Assurance of Some Heat Treated Meat Products

The aim of this work was to assure the quality of some heat treated meat products, through organoleptic, chemical and microbiological aspects of these products. These products were Luncheon, Frankfurter and Hot dog. A total of 75 samples of final products of Luncheon, Frankfurter and Hot dog (25 / each) were collected randomly from supermarkets in Cairo Province and transferred directly (in a dry icebox) to the laboratory under complete aseptic condition with a minimum of delay. All samples were subjected to organoleptic, chemical and microbiological examination to evaluate their quality status. The results of organoleptic examination revealed that the odour ranged from good to very good, medium to very good and fair to good in Luncheon, Frankfurter and Hot Dog respectively while colour and consistency was good to very good in the three products. The results of chemical analysis revealed that the chemical indicators pH, Total Volatile Nitrogen (T.VN.) and Thiobarbituric Acid (T.B.A.) were within the permissible limits according to EOS (2005). For the chemical examination the mean value of total mesophilic bacterial count was 5.73×102 ± 2.08×102cfu/g, 2.07×106 ± 3.04×105cfu/g, and 1.83×106 ± 2.76×105cfu/g. Also, it was revealed that 100% of the examined samples of total mesophilic count of luncheon were less than the permissible limits according to EOS, (2005) while, 100% of samples of frankfurter and hot dog exceeded the permissible limits when compared with the same standard. The mean value of coliforms count were 2.92 ± 0.31cfu/g, 5.12 ± 0.25 cfu/g, and 6.92 ± 0.27cfu/g for Luncheon, Frankfurter and Hot Dog respectively. The three products were free from Salmonella. Luncheon was free from E.coli and S. aureus while frankfurter and hot dog both of E.coli and S. aureus were isolated in the rate of 80 and 12% respectively. And obtained results indicated that the gram negative coliforms and gram-positive bacteria were present predominantly, Moreover, Moulds and Yeasts counts. Moulds countscfu/g ranged from 0 to 2.1×104 with a mean value of 5.2×102 ± 1.5×102, from 2.2×102 to 3.5×104 with a mean value of 2.9×103 ± 2.1×102 and ranged from 3.1×102 to 4.6×104 with a mean value of 5.3×103 ± 2.2×102 in Luncheon, Frankfurter and Hot Dog respectively. Yeasts counts cfu/g were negative in Luncheon while, ranged from 0to 1.1×104 with a mean value of 3.8×103 ± 2.3×102 and ranged from 0to 1.6×104 with a mean value of 4.5×103 ± 2.1×102 in Frankfurter and Hot Dog respectively. So, it is highly recommended to apply restricted hygiene practices along all steps of processing and storage.

Effect of thyme and oregano aqueous tea infusions on the microbiological characteristics of sausages

In this work the antimicrobial effect of Thymus vulgare and Origanum vulgare aqueous tea infusion on the total mesophilic bacterial count (TVC), psychrotrophic bacteria count (PBC) and enterococci count in the heat treated meat product - sausages were evaluated. To prepare 1 kg of sausage in experimental groups were used 10 cm3 of Thymus vulgare resp. Origanum vulgare aqueous tea infusions. It was found that value of TVC and PBC in the experimental groups of sausages with Thymus vulgare addition after 7 days of storage (4 °C) were 2.78 resp. 2.14 log cfu.g-1 and with the Origanum vulgare addition were 2.49 resp. 1.90 log cfu.g-1. The value of TVC and PBC in the control group of sausage were 3.13 resp. 2.72 log cfu.g-1. During 10 days of storage (4 °C) the TVC and PBC in the sausages with Thymus vulgare addition increase and reached the value 4.81 resp. 3.52 log cfu.g-1. In the sausages with the Origanum vulgare addition TVC and PBC after 10 days of storage reached the value 3.67 resp. 1.60 log cfu.g-1. The value of TVC and PBC in the control group of sausage after 10 days of storage were 6.47 resp. 5.47 log cfu.g-1. Counts of enterococci in control and experimental groups of sausages during 10 days of storage were not detected. Thyme and origanum aqueous tea infusions suppressed the development of TVC and PBC compare to control samples.

Viable Mycobacterium avium ssp. paratuberculosis isolated from calf milk replacer

When advising farmers on how to control Johne's disease in an infected herd, one of the main recommendations is to avoid feeding waste milk to calves and instead feed calf milk replacer (CMR). This advice is based on the assumption that CMR is free of viable Mycobacterium avium ssp. paratuberculosis (MAP) cells, an assumption that has not previously been challenged. We tested commercial CMR products (n = 83) obtained from dairy farms around the United States by the peptide-mediated magnetic separation (PMS)-phage assay, PMS followed by liquid culture (PMS-culture), and direct IS900 quantitative PCR (qPCR). Conventional microbiological analyses for total mesophilic bacterial counts, coliforms, Salmonella, coagulase-negative staphylococci, streptococci, nonhemolytic Corynebacterium spp., and Bacillus spp. were also performed to assess the overall microbiological quality of the CMR. Twenty-six (31.3%) of the 83 CMR samples showed evidence of the presence of MAP. Seventeen (20.5%) tested positive for viable MAP by the PMS-phage assay, with plaque counts ranging from 6 to 1,212 pfu/50 mL of reconstituted CMR (average 248.5 pfu/50 mL). Twelve (14.5%) CMR samples tested positive for viable MAP by PMS-culture; isolates from all 12 of these samples were subsequently confirmed by whole-genome sequencing to be different cattle strains of MAP. Seven (8.4%) CMR samples tested positive for MAP DNA by IS900 qPCR. Four CMR samples tested positive by both PMS-based tests and 5 CMR samples tested positive by IS900 qPCR plus one or other of the PMS-based tests, but only one CMR sample tested positive by all 3 MAP detection tests applied. All conventional microbiology results were within current standards for whole milk powders. A significant association existed between higher total bacterial counts and presence of viable MAP indicated by either of the PMS-based assays. This represents the first published report of the isolation of viable MAP from CMR. Our findings raise concerns about the potential ability of MAP to survive manufacture of dried milk-based products.

Antimicrobial activity of chitosan incorporated with lemon and oregano essential oils on broiler breast meat during refrigerated storage

PurposeThe purpose of this study is to evaluate antimicrobial activity of chitosan incorporated with lemon and oregano essential oils on broiler breast meat during refrigerated storage.Design/methodology/approachIn this experimental study, antibacterial effect of lemon and oregano essential oils was measured using the microdilution method for four foodborne pathogenic bacteria. The effect of 0.5, 1 and 2 per cent (Wt./Vol.) essential oils with chitosan 2 per cent on microbial quality of broiler breast meat (slaughter age: 42 days), up to 9 days’ storage time in 4 ± 1°C temperature was evaluated. Also, organoleptic characteristics of meat samples in certain storage time were examined.FindingsThe minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) for lemon and oregano essential oils ranged between 1.41 and 11.25 and 2.81 and 22.5 mg/mL, respectively. In the treatment groups, A decrease in total mesophilic bacterial count (TMBC) was observed up to sixth day, but TMBC increased on the ninth day. Decrease in lactic acid bacteria, Enterobacteriaceae, mold and yeast in the treatment groups was observed compared with the control group up to the ninth day (p < 0.01). Overall, chicken meat containing 1 per cent lemon essential oil with chitosan had a greater acceptance rate (p < 0.01).Originality/valueIn recent years, active packaging containing essential oils have been used to maintain the quality and increase the shelf life of various types of meat, chicken, fish, shrimp, fruits, etc. Therefore, it can be suggested that using chitosan in combination with the aforementioned essential oils in combination might increase shelf life of chicken meat during refrigerated storage.

Effect of Chitosan Incorporated with Cumin and Eucalyptus Essential Oils As Antimicrobial Agents on Fresh Chicken Meat

In this study, cumin and eucalyptus essential oils were prepared and analyzed by gas chromatography–flame ionization detector. Its antibacterial effects were screened using the microdilution method for Listeria monocytogenes, Salmonella typhi, Streptococcus pyogenes and Shigella dysenteriae. The effect of the three concentrations of essential oils (0.5, 1 and 2% w/v) with 2% chitosan at 4 ± 1C temperature and storage time of up to 9 days were evaluated on the microbial quality of chicken meat. Changes in total mesophilic bacterial count (TMBC), lactic acid bacteria, Enterobacteriaceae, mold and yeast counts, and sensory properties were evaluated. The main compounds in cumin were 1,8-cineol (26.75%) and cuminaldehyde (17.1%) and the main compounds in eucalyptus were 1,8-cineol (77.32%) and limonene (8.39%). The essential oils have antibacterial effects on the four examined bacteria. In all of the treatment groups, a decrease of TMBC up to the sixth day and lactic acid bacteria, Enterobacteriaceae, mold and yeast up to the ninth day (P < 0.05) were observed. Overall acceptance rate in the chicken meat containing chitosan with 0.5% cumin essential oil created a better sense. Hence, the use of chitosan combined with cumin and eucalyptus might be suggested as an antibacterial packaging to extend the shelf life and as a flavor enhancer for chicken meat. Practical Applications: The results suggested that because chitosan film incorporated with cumin and eucalyptus can reduce meat spoilage losses and improve nutritional value, it can be used as an active packaging in the meat industry. © 2015 Wiley Periodicals, Inc.

Microbial Profile of Fresh Beef Meat

This study aimed to determinae the counts and incidences of some more indicator microorganisms and isolation of pathogenic ones. Also, total mesophilic bacterial counts, total psychrophilic bacterial counts, total enterobactereacae count, total coliforms count, total mould and yeast count as well as identification of some isolated mould. The samples used in this work have been obtained from the side surface of 100 random samples (50 samples from forequarter and from hindquarter) of beef meat that were collected from different abattoirs and butchers 's shops at Al-Boheira Province. The weight of each samples was about 100 gm This study concluded that, the beef carcasses is undergo contamination with different microorganisms that includes aerobic bacteria, Psychrotrophic bacteria, coliform bacteria and mould and yeast that constituted a great hazards to human, the main source of contamination of beef carcasses with these bacteria and fungi is fecal matter during slaughtering and evisceration and application of good sanitary measures during slaughtering and evisceration with frequent investigation and examination microbial agents on beef carcasses.

Microbial population, stability and maturity analysis of rotary drum composting of water hyacinth

Water hyacinth is a noxious aquatic weed growing over a wide variety of wetland. One of the effective methods of its treatment is rotary drum composting. Hence, microbial succession in the rotary drum composting of water hyacinth was studied along with stability and maturity. Different ratios of water hyacinth, cow dung and sawdust, i.e. 8: 1: 1, 7: 2: 1, 6: 3: 1, 5: 4: 1 and 10: 0: 0 (control), respectively, were taken. A total weight of 150 kg was maintained. Maximum degradation was observed in the trial 3 (6: 3: 1), which showed maximum temperature rise up to 56.5°C. The total mesophilic bacterial count changed from 4.73 × 1012 to 2.5 × 107 colony forming unit (CFU)/g compost during the composting period. Spore forming population reached the highest count of 3.3 × 1010 CFU/g in the thermophilic phase of composting. Actinomycetes, streptomycetes and fungi counts decreased to about 2.4 × 107 CFU/g, 6.5×105 CFU/g and 6.79 × 105 CFU/g, respectively, at the end of composting period. A maximum reduction of 78.7% in oxygen uptake rate and 90.6% in CO2 evolution rate was observed. This showed the highest stability of the compost sample. But the maximum volatile solids reduction of 45.9% signified the high content of recalcitrant lignocellulosic material. Indicator organisms were reduced to acceptable standards of sanitation.