Preparation and microbiological analysis of Tuscan sausage with added propolis extract

Abstract The aim of this study was to obtain hydroethanolic extract of propolis by extraction, assisted by focused microwave, and to apply it in Tuscan-style sausage. The extract was used at concentrations of 0.5%, 1.0% and 2.0% (w/v) in the manufacture of the sausage, which was then analyzed in cold storage at 4 °C for 56 days. The following analyses were performed: mesophilic and psychotrophic organisms; coliforms at 35 and 45 °C; positive and negative-coagulase Staphylococcus, sulfite-reducing Clostridium, and Salmonella spp. The results were below the limits established by the Brazilian legislation, with some changes at the end of the study. Consequently, propolis extract prolonged the shelf life of the Tuscan-style sausage for 56 days and it is therefore an ingredient that can be potentially used in the preparation of this product.

DMFT index assessment and microbiological analysis of Streptococcus mutans in institutionalized patients with special needs

Aim: To assess the DMFT (D = decayed; M = missing; F = filled) index of institutionalized patients with mild and moderate physical and mental disabilities and to correlate it with the Streptococcus mutans (S. mutans) counts in the supragingival bacterial biofilm. Methods: Dental examination of 28 patients aged 15 to 25 years was conducted to determine the DMFT index (number of decayed, missing and filled teeth). Supragingival plaque samples were collected from the buccal surfaces of all teeth. The samples were inoculated in SB20 medium and incubated at 37 °C for 48 hours. Spearman's correlation test was applied (p = 0.05) to evaluate the correlation between the DMFT index and the amount of S. mutans. Results: The mean DMFT recorded was 7.68 and a large mean number of S. mutans colony-forming units (cfu > 10 6) was found. No statistically significant correlation was found between the DMFT index and the number of S. mutans. Conclusions: Under the conditions of this study, no correlation was found between the DMFT index and the number of S. mutans cfu in institutionalized patients with mental retardation and physical disabilities.

Evaluation of three sampling methods for the microbiological analysis of broiler carcasses after immersion chilling

Countries have different official programs and implement different sampling methods for the detection of Salmonella on poultry carcasses. In Brazil, a 25-g sample of skin and muscle excision (SME) from the wings, neck, and pericloacal parts is used; in the European Union (EU), a 25-g sample of neck skin (NSE) is used; and, in the United States, the whole carcass is rinsed with 400 ml of diluent (WCR). In the present study, these methods were evaluated to compare Salmonella occurrence and counts of hygiene indicator microorganisms (Escherichia coli, Enterobacteriaceae, and total viable count of aerobic mesophilic bacteria) using different carcasses from the same flock and also using different analytical units taken from the same carcass. Eighty flocks, with four broiler carcasses from each, were included in this study; three broilers were sampled according to protocols from Brazil, the EU, and the United States, and the last one by all three methods. SME, NSE, and WCR provided equivalent results (P > 0.05) for Salmonella detection on broiler carcasses when using different carcasses from the same flock and when using the same carcass. The predominant serovar was Salmonella Enteritidis. For the enumeration of hygiene indicator microorganisms, WRC provided higher counts than SME or NSE (P < 0.05), when using both the same or different carcasses. Therefore, it is possible to directly compare Salmonella results in poultry carcasses when using the methods recommended by the legislative bodies of Brazil, the United States, and the EU. However, WCR provides the best results for hygiene indicator microorganisms. Copyright © International Association for Food Protection.

Microbiological analysis of dental casts stored long-term

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

The Peri-Implant Sulcus Compared with Internal Implant and Suprastructure Components: A Microbiological Analysis

Purpose: A recent in vivo study has shown considerable contamination of internal implant and suprastructure components with great biodiversity, indicating bacterial leakage along the implant-abutment interface, abutment-prosthesis interface, and restorative margins. The goal of the present study was to compare microbiologically the peri-implant sulcus to these internal components on implants with no clinical signs of peri-implantitis and in function for many years. Checkerboard DNA-DNA hybridization was used to identify and quantify 40 species. Material and Methods: Fifty-eight turned titanium Brånemark implants in eight systemically healthy patients (seven women, one man) under regular supportive care were examined. All implants had been placed in the maxilla and loaded with a screw-retained full-arch bridge for an average of 9.6 years. Gingival fluid samples were collected from the deepest sulcus per implant for microbiological analysis. As all fixed restorations were removed, the cotton pellet enclosed in the intra-coronal compartment and the abutment screw were retrieved and microbiologically evaluated. Results: The pellet enclosed in the suprastructure was very similar to the peri-implant sulcus in terms of bacterial detection frequencies and levels for practically all the species included in the panel. Yet, there was virtually no microbial link between these compartments. When comparing the abutment screw to the peri-implant sulcus, the majority of the species were less frequently found, and in lower numbers at the former. However, a relevant link in counts for a lot of bacteria was described between these compartments. Even though all implants in the present study showed no clinical signs of peri-implantitis, the high prevalence of numerous species associated with pathology was striking. Conclusions: Intra-coronal compartments of screw-retained fixed restorations were heavily contaminated. The restorative margin may have been the principal pathway for bacterial leakage. Contamination of abutment screws most likely occurred from the peri-implant sulcus via the implant-abutment interface and abutment-prosthesis interface.

Clinical and microbiological analysis of subjects treated with Brånemark or AstraTech implants: a 7-year follow-up study

AIMS: To assess the impact of different implant systems on the clinical conditions and the microbiota at implants, and whether the presence of bacteria at tooth sites was predictive of the presence at implant sites. MATERIALS AND METHODS: Subjects with either AstraTech or Brånemark in function for 7 years were enrolled. Sub-gingival bacterial samples at tooth and implant sites were collected with sterile endodontic paper points, and analyzed by the checkerboard DNA-DNA hybridization method (40 species). RESULTS: Fifty-four subjects, 27 supplied with AstraTech (n=132 implants) and 27 with Brånemark (n=102) implants, were studied. Test tooth sites had significantly less evidence of bleeding on probing (P<0.001) and presence of plaque (P<0.001) than implant test sites. Implant sites presented with deeper probing pocket depth than tooth sites (mean difference: 1.1 mm, standard error of differences: 0.08, 95% confidence intervals (CI): 0.9-1.3, P<0.001). Tannerella forsythia (P<0.05), Capnocytophaga sputigena (P<0.05), Actinomyces israelii (P<0.05) and Lactobacillus acidophilus (P<0.05) were found at higher levels at tooth surfaces. No differences in bacterial load for any species were found between the two implant systems. The odds of being present/absent at tooth and implants sites were only significant for Staphylococcus aureus [odds ratio (OR): 5.2 : 1, 95% CI: 1.4-18.9, P<0.01]. CONCLUSIONS: After 7 years in function, implants presented with deeper probing depths than teeth. S. aureus was commonly present at both teeth and implants sites. S. aureus at tooth sites was predictive of also being present at implant sites.

MICROBIOLOGICAL ANALYSIS OF TRADITIONALLY FERMENTED MILK SOLD IN KINIGI SECTOR OF MUSANZE DISTRICT IN RWANDA

A research work entitled: “Microbiological analysis of traditionally fermented milk (Ikivuguto) sold in Kinigi Sector of Musanze District,” was carried out at Higher Learning Institution of Applied Sciences (INES-Ruhengeri) Laboratory of Microbiology located near Volcanoes in the Northern Province of Rwanda. The main objective of this work was to determine the microbiological quality of traditionally fermented milk, which is consumed by Kinigi Center local people. The hypothesis was to analyze if traditionally fermented milk commercialized in Kinigi restaurants contained pathogenic bacteria such as fecal coliforms and Escherichia coli , in addition to staphylococci and yeasts. Milk samples were collected from Kinigi sector and examined in the microbiology laboratory in order to assess the microbiological quality and safety of traditionally fermented milk in rural areas. The samples were analyzed qualitatively and quantitatively for the microbes found in fermented milk sold in Kinigi Center, and the results were as follows: 7.21x107 CFU/ml for total counts; 3.89x107 CFU/ml for Lactobacillus ; 2.77x107 CFU/ml for yeasts; 1.196x105 CFU/ml for total coliforms; 9.63x104 CFU/ml for fecal coliforms and 8.92x103 CFU/ml for staphylococci. Biochemical tests were carried out and the results showed that identified pathogens were E. coli, Providencia alcalifaciens , and the staphylococci group. It was found that fermented milk contained genera and species of Staphylococcus haemolyticus , Staphylococcus aureus , Staphylococcus intermedius , Staphylococcus xylosus and Staphylococcus saprophyticus . Findings showed that the commercial milk samples were cross-contaminated by different pathogens from environment. These contaminations could have been due to improper handling, presence of flies, soil erosion, dust from atmosphere, as well as contaminated milk vessels or pots, stirrers and unpasteurized water. It was concluded that local farmers and milk retailers did not adhere to required hygienic conditions for milk safety. In this regard, the sold traditional fermented milk does not meet health and safety standards because people did not respect good manufacturing practices. The hypothesis and main objective were confirmed, because traditionally fermented milk of Kinigi was cross-contaminated before consumption. Thus, it would be better to train farmers in the areas of product hygiene, sanitation and safety during milking, processing and marketing.

Analysis of virulence genes in Escherichia coli isolated from grated cheese

This research aimed to verify the presence of virulence genes in strains of Escherichia coli isolated from grated cheese sold in farmers' markets of Cuiabá-MT, Brazil. Forty samples of this food were submitted for microbiological analysis and 22 (55%) tested positive for E. coli. Next, 64 strains of E. coli were isolated from the positive samples and screened by the polymerase chain reaction (PCR) for the presence of the genes encoding the following virulence factors: stx1 and stx2 (verotoxin types 1 and 2), eae (intimin), lt1 (heat-labile toxin type 1), st1 (heat-stable toxin type 1), cnf1 and cnf2 (cytotoxic necrozing factor types 1 and 2), and cdtB (cytolethal distending toxin). All the isolates were negative for the genes stx1, stx2, eae, lt1, st1, cnf1, and cdtB, and five strains (7.81%) were positive for cnf2. A low prevalence of E. coli positive for virulence factors associated with the pathogenesis of diarrhoea was observed in this study. However, the presence of CNF-2 producing strains and the possibility of occurrence and scattering of other virulence factors that were not surveyed in the work indicate the risk related to the consumption of grated cheese from farmers' markets.

Effect of the implementation of the Hazard Analysis Critical Control Point (HACCP) prerequisite program in an institutional foodservice unit in Southern Brazil

The aims of this study were to investigate the hygienic practices in the food production of an institutional foodservice unit in Southern Brazil and to evaluate the effect of implementing good food handling practices and standard operational procedures using microbiological hygiene indicators. An initial survey of the general operating conditions classified the unit as regular in terms of compliance with State safety guidelines for food service establishments. An action plan that incorporated the correction of noncompliance issues and the training of food handlers in good food handling practices and standard operational procedures were then implemented. The results of the microbiological analysis of utensils, preparation surfaces, food handlers' hands, water, and ambient air were recorded before and after the implementation of the action plan. The results showed that the implementation of this type of practice leads to the production of safer foods.

Characterization of spoilage bacteria in pork sausage by PCR-DGGE analysis

To investigate microbial diversity and identify spoilage bacteria in fresh pork sausages during storage, twelve industrial pork sausages of different trademarks were stored at 4 ºC for 0, 14, 28 and 42 days, 80% relative humidity and packaged in sterile plastic bags. Microbiological analysis was performed. The pH and water activity (a w) were measured. The culture-independent method performed was the Polymerase Chain Reaction - Denaturing Gradient Gel Electrophoresis (PCR-DGGE). The culture-dependent method showed that the populations of mesophilic bacteria and Lactic Acid Bacteria (LAB) increased linearly over storage time. At the end of the storage time, the average population of microorganisms was detected, in general, at the level of 5 log cfu g-1. A significant (P < 0.005) increase was observed in pH and a w values at the end of the storage time. The PCR-DGGE allowed a rapid identification of dominant communities present in sausages. PCR-DGGE discriminated 15 species and seven genera of bacteria that frequently constitute the microbiota in sausage products. The most frequent spoilage bacteria identified in the sausages were Lactobacillus sakei and Brochothrix thermosphacta. The identification of dominant communities present in fresh pork sausages can help in the choice of the most effective preservation method for extending the product shelf-life.

Microbiological and sensory evaluation of Jambu (Acmella oleracea L.) dried by cold air circulation

Abstract The aim of this study was to evaluate the microbiological and sensory quality of the Jambu (Acmella oleracea L.) in natura and dried by cold air, and the determination of its drying curve. The microbiological analysis were performed to Salmonella spp, the coagulase-positive Staphylococcus, and coliforms in the both Jambu samples, at 45 °C. Tacacá, the typical food dish of Pará state, Brazil, has showed good consumer global acceptance in the sensory evaluation of Jambu in natura (score of 8.00 ± 1.46) and dried (score of 8.67 ± 0.66). Both samples, Jambu in natura and dried by cold air, were by the current legislation regarding the microbiological aspects, this is the absence of Salmonella spp, coagulase-positive Staphylococcus <1×101 CFU/g, and coliforms <3 MPN/g, at 45 °C. Thus, considering sensory and health aspects, the commercialization of dried Jambu becomes viable, facilitating its transportation and handling, as well as for reducing its vegetable mass.

Microbiological quality of meals served in nursing homes in the city of Ponta Grossa, Paraná

Abstract The aim of this study was to analyze the microbiological quality of meals served in nursing homes in the city of Ponta Grossa, Paraná, before and after the training of food handlers. The first stage was to perform a checklist conforming with current legislation. The second consisted of the collection of 4 food samples from each location and a microbiological investigation in accordance with the relevant legislation. The third was the training of food handlers in relation to good food handling practices. The fourth was a further microbiological analysis of new samples. The application of a checklist showed that the locations met the requirements of current legislation. Of the 40 samples analyzed, 17.5% (7 samples) were unfit for consumption. Among the unfit samples 15% (6 samples) had coliforms at 45 °C, 2.5% (1 sample) had coagulase-positive staphylococci, 2.5% (1 sample) had Bacillus cereus and 2.5% (1 sample) had Salmonella sp. The results of this study show the importance of controlling the quality of food served to an age group that is prone to health risks.

Effects of different packaging techniques on the microbiological and physicochemical properties of coated pumpkin slices

Abstract In this study the effects of zein film coating along with benzoic acid on the quality of sliced pumpkin samples, which were packaged with different techniques were investigated. The samples were allocated into different groups and were treated with different processes. Following processing, the samples were stored at +4 °C for twenty days. Physicochemical and microbiological analyses were carried out on the samples once every five days during the storage period. According to color analysis, the L* value was observed to have significantly decreased in the processed and packaged samples in comparison with the control group. Besides, a* and b* values increased in all groups. It was determined that zein film alone did not exhibit the expected effectiveness against moisture loss in the samples. According to the results of microbiological analysis, a final decrease at approximately 1.00 log level was determined in total count of mesophilic aerobic bacteria (TMAB) in the group which was vacuum packaged in PVDC with zein coating when compared with the initial TMAB. Furthermore, no molding occurred in zein-coated group on the last day of the storage period, while massive mold growth was noted in the group which was packaged without any pretreatment procedure.