Counts Of Mesophilic Microorganisms Research Articles

Inhibition of Salmonella enteritidis in homemade mayonnaise using oregano essential oil (Origanum vulgare)

The potential of oregano essential oil (OEO) as a natural antimicrobial agent to mitigate Salmonella spp. contamination in homemade mayonnaise made from raw eggs should be explored. This study aimed to assess the viability of Salmonella Enteritidis in homemade mayonnaise supplemented with OEO while also examining key quality parameters, including pH, titratable acidity, and the count of mesophilic aerobic microorganisms. In vitro experiments determined the Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) of OEO against two strains of Salmonella Enteritidis and one of Salmonella Typhimurium. Subsequently, homemade mayonnaise, intentionally contaminated with a Salmonella Enteritidis strain, was prepared, and OEO was added at concentrations of 0.5% and 1.0%. Bacterial plate counts for Salmonella spp. and mesophilic microorganisms, as well as acidity levels, were assessed at 0, 4, 8, and 24 hours of incubation at 30°C. The results indicated the in vitro efficacy of OEO, with an MIC of 0.5% and an MBC of 0.0625% against all strains. However, in homemade mayonnaise, Salmonella counts averaged 6.0 log CFU/g over the 24 hours at 30°C. Mesophilic microorganism counts also averaged 6.0 log CFU/g over 24 hours, similar to those of Salmonella. The pH values ranged from 4.5 to 5.1, and acidity levels remained between 0.31% and 0.39% throughout the 24 hours. In conclusion, oregano essential oil exhibited a bacteriostatic effect, effectively limiting the growth of Salmonella Enteritidis in homemade mayonnaise at the evaluated concentrations and time intervals.

Composition and microbiological quality of raw milk refrigerated in community tanks

Milk is rich in nutrients, but several factors in the production system interfere with its quality. The objective of this study was to analyze the composition and microbiological quality of raw milk stored in community tanks from the municipality of Aricanduva – Minas Gerais. Samples were collected from eight community tanks at different properties. The milk composition and temperature were analyzed using the digital milk analyzer. The total count of aerobic mesophilic microorganisms was performed at the Laboratory of Science and Technology of Products of Animal Origin, Department of Animal Science, Federal University of Vales do Jequitinhonha and Mucuri, Diamantina – Minas Gerais. The data obtained were compared to the values established by Normative Instruction (IN) n° 76, by means of Student's t-test and Wilcoxon's non-parametric test at the level of 5% of significance. The average levels of fat (3.55 g/100g), protein (3.00 g/100g), lactose (4.45 g/100g) and total solids (11.76 g/100g) were within the standards minimum required. The content of defatted solids (8.21 g/100g) was the limiting factor to the compliance with IN76, with an average value lower than that established (8.40 g/100g). The temperature of the milk was higher than the standard required by the legislation and the count of mesophilic microorganisms did not differ from the legislation. It is concluded that the composition of raw milk stored in community tanks in the municipality of Aricanduva – Minas Gerais, compared to IN 76, did not fully met the legislation in all evaluated parameters.

Raw Cow Milk Protein Stability under Natural and Technological Conditions of Environment by Analysis of Variance.

Heat stability (HS) is substantial technology property of raw milk. Analysis of sources of HS variation and its regular monitoring can contribute to creating higher added value in the dairy industry. The goal of this analysis was to assess the practice sources of raw cow milk HS variability on the results of an extensive data set of bulk tank milk samples. There was implemented neither a compositional technology modification nor acidity adjustment of milk, just original raw milk was used for the analysis. A total 2634 HS analyses were performed, including other milk indicators, during three years of an experimental period. The log HS mean and standard deviation were 1.273654 ± 0.144189, equal to the HS geometric mean of 18.8 min. Explanation of the HS variability through the linear model used was 41.1% (p < 0.0001). According to the results of the variance analysis, the milk HS was influenced (p = 0.0033 and mostly <0.0001) by all the farm factors such as year; season; calendar month; altitude; total annual rainfall; herd size by the number of cows; milk yield; cow breed; type of milking; litter type in the stable; summer grazing application; farm effect. During the calendar months (p < 0.0001), milk HS values suggest similar seasonal dynamics with the somatic cell count, total count of mesophilic microorganisms, coli bacteria count and urea and lactose concentration and opposite configuration pattern to fat, crude protein, solids-not-fat and total solids content and milk freezing point depression. Here performed quantification of these effects by analyzing the variance may allow efficient raw milk selection to be processed into specific dairy products.

Presence of Listeria monocytogenes and Salmonella spp. in lamb meat commercialized in Uruguaiana, Rio Grande do Sul, Brazil.

The aim of this study was to evaluate the hygienic-sanitary quality of lamb meat sold in the city of Uruguaiana, Rio Grande do Sul (RS) by counting the indicator microorganisms and detecting pathogens such as Salmonella spp. and Listeria monocytogenes. Thirty-nine lamb meat samples were collected from 10 commercial establishments in Uruguaiana. The samples were subjected to counts of aerobic mesophilic microorganisms and enterobacteria, and to the detection of Salmonella spp. and L. monocytogenes, all following standard methods. The average counts of mesophilic microorganisms and enterobacteria were 6.08 log CFU/g (minimum 4.07 and max 6.87) and 4.73 log CFU/g (minimum 0 and max 5.88), respectively. For pathogens, L. monocytogenes was isolated from five samples (12.82%), with three samples in the same location. Only two samples (5.13%) were positive for Salmonella spp. The results demonstrated unsatisfactory hygienic-sanitary conditions because high counts of pathogens such as Salmonella spp. and L. monocytogenes. The counts of enterobacteria showed poor hygiene conditions during the various stages of production. The results also indicated fecal contamination, as Salmonella spp. and L. monocytogenes are present in the intestinal tract of both humans and animals. The high count of mesophilic microorganisms obtained could be owing to contaminated raw material or unsatisfactory processing, including unsanitary conditions and the inappropriate use of binomial time/temperature during storage.

Monitoring and Optimization of Cupuaçu Seed Fermentation, Drying and Storage Processes.

Cupuaçu [Theobroma grandiflorum (Wild ex Spreng.) K. Schum] seeds have been employed for a long time in the Amazon region for food purposes. Similar to cocoa, processed cupuaçu pulp and seeds can be used to produce juices, ice creams, confectionary products and cupulate®, which is a similar product to chocolate. However, its market penetration requires the mastery of all processing stages to improve the food quality and safety and to make possible an efficient technology transfer to the local small farmers and communities. Based on the above, the current research work aimed at monitoring and optimizing the consecutive fermentation and drying processes of cupuaçu seeds over 7 days each, as well as storage for 90 days. A greenhouse structure incorporating the fermenter and solar drying terrace was designed to be inexpensive, versatile, easily scalable, and easy to maintain and operate by the local small farmers after a short period of training. This research effort also aimed at giving a vision for the future creation of an integrative and sustainable cupuaçu system covering the economic, social, cultural and environmental vectors. The experimental design comprised 5 batches of 100 kg of seeds each. Several microbiological and physicochemical parameters were performed and correlated with processing variables. Microbiological parameters encompassed viable counts of mesophilic microorganisms, coliforms, yeasts, and molds, whereas physicochemical measures included fermentation and drying temperature, pH, acidity, dry matter, ashes, water activity, color, total proteins, lipids and carbohydrates, and energy. The average seed fermentation temperature varied from ca. 28 to 44 °C, reaching the maximum on day 3 and a final value of ca. 31 °C. Regarding solar drying, the average seed temperatures ranged from ca. 24 °C (at the end) to 39 °C on day 3, and an initial value of ca. 29 °C. The average final seed pH value of drying was 5.34 and was kept during storage. During storage, results demonstrated the existence of significant correlations among several experimental parameters under scrutiny. Finally, bean viable counts obtained during storage unfolded acceptable values of total mesophilic bacteria well below the maximum limit. Viable counts of yeast and molds were generally found between 3 and 4 log(CFU/gsample), and total coliforms were also detected, although both were at acceptable levels and well beneath the established maximum limits for food safety.

Influence of storage period and shelf-life on the incidence of chilling injury and microbial load in "Angeleno" and "Larry Ann" plums

Refrigeration is the most widely used post-harvest technology for increasing commercial life (shelf-life) of plums after harvest. Nevertheless, low-temperature conservation is limited by chilling injury (CI), leading to rejection by consumers. The objective of the present work was to characterize biotic and non-biotic chilling injures that lead to quality loss in plums during post-harvest storage. Larry Ann and Angeleno plums were stored at 1.0±0.5°C and 90.0±2.0% RH for 4 and 8 weeks and after this period the plums were stored either 3 or 6 days at 20ºC for evaluating changes in their shelf-life. Pulp firmness, post-harvest losses, presence of chilling injuries and the count of mesophilic microorganisms, molds and yeasts were determined after harvest and after storage plus shelf-life. In general, a drastic decrease in the growth of bacteria, mold and yeast during post-harvest storage at 1ºC was observed, following an increased microbial growth during shelf-life storage. Sensitivity to low temperature was cultivar-dependent. Larry Ann plums showed higher pulp firmness reduction and lower impact of CI than Angeleno, with an increased microbial spoilage. Plums that presented cold-damaged or physiologically compromised tissues suffered from faster decomposition and provided a better substrate for microbial growth than non-damaged plums.

Occurrence ofArcobacter spp. in Brazilian Minas frescal cheese and raw cow milk and its association with microbiological and physicochemical parameters

Some Arcobacter species are considered emerging food-borne pathogens. However, their prevalence in dairy products is not well known. Therefore, the aim of the current research is to know the occurrence of Arcobacter species in Minas frescal cheese and raw cow milk and its potential association with physicochemical and microbiological parameters. Two hundred and one food samples (cheese, n = 98 and milk, n = 103) collected between 2016 and 2017 in São Paulo State, Brazil, were analyzed. Arcobacter was isolated using an enrichment broth with further filtration over Arcobacter agar. Colonies were characterized by ERIC-PCR, m-PCR and PCR-RFLP and, when was necessary, sequencing of 16S rRNA and rpoB genes were also assessed. Additionally, cheese samples were evaluated in relation to total coliform (TC), thermotolerant coliforms (TtC), coagulase positive staphylococci (CoPS) count and moisture. Raw milk samples were assessed for aerobic mesophilic bacteria count, TC, TtC, Dornic acidity, proteins, fats, lactose, defatted dry extract, total solids and somatic cell counts. The occurrence of Arcobacter was 10.2% (10/98) and 16.5% (17/103) in cheese and milk samples, respectively. All isolates were identified as Arcobacter butzleri. On the other hand, Multiple Factorial Analysis showed correlation between the presence of this species and the cheese moisture, while this pathogen was correlated with high counts of mesophilic microorganisms and TC in raw milk. No other evaluated parameter in cheese (TC, CoPS) and milk (TtC, Dornic acidity, proteins, fats, lactose, defatted dry extract, total solids and somatic cell counts) showed significant correlation. To date, this is the first report on A. butzleri in Minas frescal cheese, therefore its presence in dairy products could be considered a potential public health concern.

Seasonal Correlations Between Heat Stability and Other Raw Bulk Cow Milk Quality Indicators

Heat milk stability (thermostability, TES) is important technological feature which can contribute to create higher added value in the dairy industry. The aim of this paper was to evaluate the seasonal dynamics and relationships of TES to other milk qality indicators in the results of an exceptionally large data set of bulk samples without technological compositional modification and acidity adjustment, just with native raw cow milk. There were carried out 2,634 of TES measurements including other milk indicators during 3 years under controlled farm conditions. Results were processed by polyfactorial linear model of variance analysis and linear and nonlinear regression method. Correlation indexes of seasonal dependence of milk indicators such as fat content (F), crude protein content (CP), lactose monohydrate concentration (L), solids non‑fat content (SNF), total solids (TS), urea concentration (U), F/CP ratio, F/L ratio, milk freezing point (MFP), somatic cell count (SCC), total count of mesophilic microorganisms (TCM) and coli‑form bacteria count (COLI) were significant (P &lt; 0.05 and &lt; 0.01) including TES (r = 0.869; P &lt; 0.01), with the exception of F/CP (P &gt; 0.05). The seasonal dynamics of milk TES values corresponds positively with the trends of U and L. The negative seasonal trends are between milk TES and F, CP, SNF, TS, F/CP, F/L and MFP. Significant (P ≤ 0.1) negative seasonal correlations were between TES and F, CP, TS and F/L (–0.56, –0.55, –0.54 and –0.57). Significant (P ≤ 0.05) positive seasonal correlations were between TES and U and TCM (0.62 and 0.58). Insignificant (P &gt; 0.1) negative seasonal correlations were found between TES and SNF, F/CP and MFP (–0.49, –0.29 and –0.16). Insignificant (P &gt; 0.1) positive seasonal correlations were between TES and L, SCC and COLI (0.44, 0.42 and 0.43). Performed explanation of possible effects of chosen factors on raw cow milk TES can allow efficient selection of raw material for its processing by technological treatment under high temperature into relevant dairy products.

Efecto del mínimo procesamiento y tratamiento con yerba mate sobre el potencial saludable y los atributos de calidad de manzanas Granny Smith

The effect of the minimal processing with and without treatment with citric and ascorbic acids and yerba mate on the physicochemical, bioactive, microbiological and sensory characteristics of ‘Granny Smith’ apples was studied. Soluble solids and polyphenol contents, total aerobic mesophilic microorganism counts, sour taste and the browning sensory attribute were reduced by the minimal processing (without chemical treatment), while the sensory general appearance improved. When comparing the results obtained for the treated and untreated (control) freshcut apples, it was observed that the applied chemical treatment reduced the characteristic flavor of the apples and increased the sour taste, off-flavors and off-odors. However, the treatment was effective in controlling the browning development (L* increased, sensory general appearance improved and a* and sensory attribute browning decreased), in increasing the healthy potential (higher polyphenol and vitamin C content and antioxidant capacity), and maintaining the microbial counts similar to those obtained for the raw material.

A diagnosis of the microbiological quality of dehydrated bee-pollen produced in Brazil.

Bee-pollen is an apicultural product with potential for medical and nutritional applications; therefore, its microbiology quality should be monitored. In this context, the objective of this study was to diagnose the microbiological quality of 45 dehydrated bee-pollen samples collected from November 2011 to December 2013 in nine Brazilian States. All the samples were negative for sulphite-reducing Clostridium spores, Salmonella, coagulase-positive Staphylococcus and Escherichia coli, which are micro-organisms of public health concern. Total aerobic mesophilic micro-organism counts ranged from <10 to 1·10 × 10(4) CFU g(-1) , with psychrotroph counts ranging from <10 to 1·12 × 10(3) CFU g(-1) and total coliforms from <10 to 2·80 × 10(3) CFU g(-1) , while the values for yeasts and moulds were between <10 to 7·67 × 10(3) CFU g(-1) . According to the literature, the microbiota observed in this study were typical; however, it is important to consider that these micro-organisms may cause spoilage and diminish shelf life, reason by which quality control programs should be implemented. Contamination of bee-pollen can occur during production, collection and processing, but there are few studies of the microbiological quality of this product. Brazil is an important producer of dehydrated bee-pollen, therefore, a diagnosis of the microbiological status is important to ensure the safety of many consumers. Salmonella sp., genus Clostridium, coagulase-positive Staphylococcus, Escherichia coli and even some yeast species are micro-organisms of public health concern and their presence must be monitored. Furthermore, the determination of spoilage micro-organisms indicates whether the production and the processing practices carried out by beekeepers and warehouses were adequate.

Microbiological quality of enteral feeding and infant formula produced in dietary units, according to the triad of Donabedian.

Microbial contamination of enteral feeding and infant formulas can result in a risk of worsening of the clinical condition of the patients, who are already weakened and susceptible to pathogens. The objective was to evaluate aspects of the management of quality hygienic - sanitary of enteral feeding and infant formulas in hospitals, focusing on the structure, process and outcome. An observational, descriptive, prospective, with quantitative and qualitative variables study was done. The survey was conducted for 12 months and 227 samples of enteral feeding and 176 of infant formula were collected in Nutrition and Dietetic Services of Health Secretary / Federal District. In evaluating the operating conditions, the Tool 2 was applied to: Enteral Nutrition Preparation. Data were analyzed from the unified Donabedian's triad for evaluation of health services. The results obtained with the Tool 2 demonstrated that the Storage Block complies with legal requirements. Moreover, Dressing Block is a risk factor for the contamination. From the 403 samples, 56% corresponded to samples of Enteral Nutrition and 44% to samples of Infant Formulas. The data indicate that from 227 samples of Enteral Nutrition, 6.2% were in disagreement with the legislation, while from 176 samples of Infant Formulas, 4.6% were also in disagreement with the legislation. The ineffective implementation of the sanitary and hygienic requirements during the preparation results in a microbiologically unsafe product to patients in debilitated health state, and the count of mesophilic microorganisms can be a good indicator of microbiological safety.

Short-term storability of oil seed and walnut cake — microbiological aspect

We evaluated the microbiological safety, the short-term storability, and the macronutrients of oil seed cake (OSC) obtained from walnut (WnC), linseed (LC), and sunflower seed with hull (SC). The OSCs had 3.6–5.8% moisture content, 0.50–0.60 water activity (aw), 29.9–39.4% protein, 15.5–23.6% fat, and 36.6–48.0% dietary fibre content. The grinded OSCs could be stored in opaque plastic bags for 4 months at temperatures of 4 °C, 14 °C, and 25 °C. Total colony count of mesophilic microorganisms depending on oxygen demand and spore-forming ability, and faecal indicator microorganisms were determined during a 4-month storage term at 4 °C, 14 °C, and 25 °C using traditional culturing methods. The OSCs were free from sulphite-reducing Clostridia and coliforms, including Escherichia coli. Data were analyzed statistically by multifactor analysis of variance. Ascending order of the average contamination of the three products (log10 CFU g−1) was aerobic sporogenic bacteria (2.39), fungal count (2.51), total aerobic ...

ATP-Bioluminescence as a method to evaluated microbiological quality of UHT milk

New approaches are needed to quickly indicate possible contamination of UHT milk, among them the technique of ATP-Bioluminescence. Therefore, the aim of this study was to compare the results of culture methods with the results of ATP-Bioluminescence technique of 102 UHT whole milk samples incubated at 48, 72, and 168 hours. UHT milk samples were analyzed for the presence of mesophilic and psychrotrophic aerobic microorganisms using Plate Count Agar (PCA), Brain-Heart Infusion (BHI) media and PetrifilmTM Aerobic Count (AC) plates. The ATP-Bioluminescence technique was applied through the Microbial Luminescent Screening (MLS) system. Significant correlations were found between counts of aerobic mesophilic microorganisms on PCA, PetrifilmTM AC, BHI and results of ATP bioluminescence technique (P≤0.05). The ATP-Bioluminescence technique had higher correlation with counting method in PCA than BHI media. At lower pass/fail limits of Relative Light Units (60, 50, 45 and 40 RLU), the number of samples identified as positive increased and statistically agreed with aerobic mesophilic microorganism counts (P&gt;0.05). For the dairy industry, the ATP-Bioluminescence technique may become an important tool that assists the official methods to quickly monitor the microbiological quality of UHT milk though this will likely require a threshold below 150 RLU.

Qualidade microbiológica e temperatura de dietas enterais antes e após implantação do sistema de análise de perigos e pontos críticos de controle

OBJETIVOS: Avaliar a qualidade microbiológica e a temperatura de dietas enterais antes e após a implementação do sistema Análise de Perigos e Pontos Críticos de Controle na Central de Produção de Alimentação Enteral do Hospital de Clínicas de Porto Alegre. MÉTODOS: Durante o período de setembro de 2001 a janeiro de 2002, foram coletadas 320 amostras de 4 tipos de dietas enterais produzidas na Central de Produção de Alimentação Enteral (dietas padrão I, II, III e dieta especial), as quais foram submetidas a análises microbiológicas e de temperatura. As amostras foram coletadas semanalmente em dois pontos do processo: logo após o preparo e após 16 horas de armazenamento refrigerado. Para comparação dos dados pré e pós análise dos perigos em pontos criticos e de controle, utilizou-se o teste "t" de Wilcoxon para amostras pareadas (teste não-paramétrico equivalente ao teste "t" de Student para amostras pareadas) com nível de significância de 0,05. RESULTADOS: Antes da análise de perigos e pontos críticos de controle, 92% das temperaturas de armazenamento estavam acima dos valores de refererência vigentes. Após a implantação da análise de perigos e pontos críticos de controle, houve reduções significantes (p&lt;0,05) nas contagens de microrganismos mesófilos totais das dietas II, III e Especial, logo após preparo. Reduções significantes também foram encontradas nas dietas II e III armazenadas sob refrigeração. Não foram encontrados coliformes fecais, Staphylococcus aureus, Bacillus cereus, Clostridium sulfito redutores, Salmonella sp., Yersinia enterocolitica ou Listeria monocytogenes em nenhum dos momentos avaliados. A análise crítica do fluxograma de produção identificou as etapas de aquisição de matéria-prima e de armazenamento sob refrigeração como Pontos Críticos de Controle das dietas produzidas. CONCLUSÃO: Com a implantação deste sistema na central de produção de alimentação enteral foram realizadas mudanças que contribuíram significativamente na qualidade do produto final, diminuindo riscos de contaminação alimentar.

The correlation between aerobic mesophilic microorganism counts and Dornic acidity in expressed human breastmilk

The study was designed to test for the existence of a correlation between the total population of aerobic mesophilic microorganisms in processed raw breastmilk from a human milk bank and the Dornic acidity of that milk. Two hundred consecutive samples of thawed expressed human breastmilk obtained from human milk bank, prior to pasteurization. Dornic acidity was titrated in triplicate for each sample. Aerobic mesophilic microorganisms were then plate counted. Data were analyzed to detect correlations between variables, using Pearson's coefficient, and the level of significance was set at p < or = 0.05. In the samples analyzed, Dornic acidity levels had a positive (R = 0.948) and statistically significant (p < or = 0.001) correlation with the population of aerobic mesophilic microorganisms (CFU/mL). The data obtained here support to the conclusion that Dornic titration is an effective method for the indirect evaluation of bacterial growth in expressed human milk.

Characterization of Bacillus cereus Isolates from Raw Soybean Sprouts

Raw soybean sprouts, which are used as ingredients in cook-chilled products, were analyzed to evaluate the incidence of mesophilic aerobic microorganisms, psychrotrophic microorganisms, anaerobic microorganisms, coliforms, and spore-forming microorganisms Bacillus cereus, Clostridium botulinum, and Clostridium perfringens. Mesophilic microorganisms on raw soybean sprouts were present in large populations, 5.5 × 106 to 1.4 × 108 CFU/g, and psychrotrophic microorganisms were found to be more numerous than the other groups. Coliforms accounted for 15% of mesophilic microorganism counts on average, and the average for spore-forming microorganisms was 5.2 × 102 CFU/g. B. cereus was isolated from 12 of 17 soybean sprout samples, whereas C. botulinum and C. perfringens were not isolated. B. cereus was isolated in greater numbers at 30° C compared with other temperatures and was not isolated at 4° C. Of the 55 strains isolated from soybean sprouts, 52 were positive for starch hydrolysis, and only 3 strains did not hydrolyze starch. Among the 55 strains of B. cereus isolates, 53 showed the ability to produce diarrheal enterotoxin by CRET-RPLA.

SHELF-LIFE OF FRESH FILLED PASTA. HAZARD ANALYSIS AND CRITICAL CONTROL POINTS OF THE MANUFACTURING PROCESS AND HOUSEHOLD PRACTICES

Hazard Analysis and Critical Control Point (HACCP) approach was used to assess the safety of a fresh filling pasta (ricotta-filled ravioli) manufacturing plant in La Plata region, Argentina. Household practices like cooking and holding meals before serving were also evaluated. Samples of ricotta, main raw material of the filling, showed colony counts of Enterobacteriaceae total microorganisms, molds and yeasts of (5 x 10(3)-1 x 10(5)), (1 x 10(5)-1 x 10(8)) and 1 x 10(5) CFU/g, respectively. E. coli was also detected in one out of five samples, suggesting a hazardous condition of this raw material. Salmonella spp. was not isolated from any of the dough samples tested. Ricotta filling showed high colony counts of mesophilic microorganisms (6 x 10(6) CFU/g), Enterobacteriaceae (1 x 10(5)-1 x 10(6) CFU/g), while E. coli was detected in 20% of the samples. Counts of B. cereus, S. aureus were less than 1 x 10(2) CFU/g in the analyzed materials. In the finished product (ricotta-filled ravioli), the colony counts of mesophilic microorganisms and Enterobacteriaceae were 3 x 10(8) and 8 x 10(5) CFU/g, respectively. Critical Control Points found were cooking and holding time before serving. The implementation of suggested corrections allowed the microbial quality of the final product (ricotta-filled ravioli) to be improved considerably. The growth of total microbial counts during refrigerated storage (0, 4, 8 and 10C) were measured and the shelf-life of ricotta and ricotta-filled ravioli was calculated.

Changes in physical, chemical, and microbiological characteristics of brines applied in the salting of mozzarella cheese during the period of utilization

Variation of the physical, chemical and microbiological characteristics of brines during their utilization for salting mozzarella cheese. Forty brine samples used for submersion salting of mozzarella cheese in a dairy industry in the State of S. Paulo, Brazil, were analysed for the purpose of discovering the variation in the physical, chemical and microbiological characteristics observed over their period of utilization. The mean values preparation up to the 21st day of utilization of pH, sodium chloride and protein concentration varied from 7.21 to 5.76, from 27.1 to 24.5 and from zero to 0.126 mg/ml, respectively over the period from their. The mean values of the mesophilic microorganism counts and of the total and fecal coliforms MPN varied from 5.8 x 10 CFU/ml to 6.9 x 10(4) CFU/ml, from zero to 1.6 x 10(5)/100 ml and from zero to 1.1 x 10(5)/100 ml, respectively. Moreover, the mean values of mould and yeast and Staphylococcus positive coagulase counts varied from 0.4 x 10 CFU/ml to 2.0 x 10(3) CFU/ml and from zero to 1.3 x 10 CFU/ml, respectively. The results obtained suggest that the hygienic conditions during the preparation and the utilization of the brine were not satisfactory so that they may represent an important source of contamination for the cheeses. The quality of the product may be harmed, as a result of this fact, in such a way as to represent a potential hazard for the health of the consuming population.