Microbiological Quality Of Raw Milk Research Articles

Improvement of Raw and Pasteurized Milk Quality through the Use of Lactoperoxidase Systems (LPSs) along the Dairy Value Chain, under Real Conditions in Ethiopia.

Lactoperoxidase systems (LPSs) can enhance the microbiological quality of raw milk when there is lack of cooling facilities. In this study, a total of 250 milk samples were collected from farmers, collectors, and factories. Experimental samples were both LPS-activated morning and overnight milk. The samples were tested with several chemical and microbiological tests, such as total bacterial count (TBC), total coliform count (TCC), and Escherichia coli count (EC). Results indicated that all LPS-activated milk samples had a higher quality than all the control samples. For instance, both the morning and overnight farm milk samples had mean TBCs of 5.79 log and 6.55 log cfu/mL, which is significantly (p < 0.05) lower than the control samples' mean TBC of 6.73 log and 7.31 log cfu/mL, respectively. When this was compared with the Ethiopian Standard, 51.4% of morning and 39.5% of overnight farm milk with LPS activation met the acceptable quality, while only 28% of morning and 15.7% of overnight control milk met the standard. Moreover, LPS activation has also significantly improved the shelf life of collectors' raw milk and pasteurized milk at the factories. Therefore, a better hygienic practice with LPS application can be practiced in conditions that lack cooling infrastructure and electricity.

Microbiological quality of raw milk: community expansion tanks in Alagoas

Milk is a highly nutritious food consumed by a large part of the population, and due to its nutritional composition, its quality can be altered by the amount of microorganisms present. The objective of this study was to evaluate the microbiological quality of raw milk from community expansion tanks in the state of Alagoas. A total of 160 milk samples were aseptically collected from the three mesoregions of the state for microbiological analysis. It was observed that 10.83% (13/120) of the samples had Staphylococcus coagulase-positive counts lower than 105 CFU/mL, and 10.83% (13/120) had counts higher than 105 CFU/mL. For coliforms, 18.8% (30/160) were found to have counts less than 1.1×103 MPN/mL, while 81.2% (130/160) of the samples had values higher than 1.1×103 MPN/mL. No Salmonella spp. or Listeria spp. were found in any of the samples. Aeromonas spp. was found in 28.7% (46/160) of the samples. For mesophilic microorganisms, 15% (24/160) of the samples were within the standard required by legislation, while 85% (136/160) were outside the established limit of up to 6×105 CFU/mL. Psychrotrophic microorganism counts were higher than 5×106 CFU/mL in 41.9% (67/160) of the samples analyzed. It was concluded from this study that the high microorganism counts in the analyzed milk and the inadequate temperature of the tanks at the time of collection can lead to the production of a low-quality product due to the deteriorative or pathogenic action of the microorganism. Therefore, the implementation of good practices during milking, transportation, and storage of refrigerated raw milk is suggested to prevent contamination of the raw material, ensuring a product with certified quality.

Physico-chemical and microbiological quality of raw milk produced by smallholder farmers in Gulu City, Northern Uganda

Physico-chemical and microbiological quality of raw milk produced by smallholder farmers in Gulu City, Northern Uganda

Evaluation of the Hygienic and Microbiological Quality of Raw Milk from Cows Intended For Consumption or Processing in the Town of Abéche in Chad.

The objective of this study was to identify the sources of microbial contamination of was milk and to evaluate the degree of microbiological contamination of was milk, to isolate the suspected pathogenic germs in the milk consumed. A total of 30 farmers were surveyed simultaneously at the time of collecting 30 samples. The samples were immediately transferred to the laboratory for microbiological analysis. Pathogens were investigated according to standard microbiological methods. The analysis of was milk made in the laboratory of INSTA chowed that the load of FAMT was variable between 4, 00.104 cfu /ml to 7, 15.107 ufc /ml, those of CT and CF were included between 103 cfu / ml to 5,73.104 cfu /ml and staphylococcus aureus was between 1,36.102 cfu /ml to 4.5.103 cfu /ml. the microbiological quality of the raw milk samples according to FAMT, CT and CF were mostly unsatisfactory. The microbiological quality of the raw milk sample according to staphycocus aureus was mostly uncontaminated. In the light of these results, the improvement of the microbiological quality of milk based on the establishment of a quality policy, aimed at popularizing the application of good hygiene practices throughout the chain of milk production and veterinary monitoring could contribute to improving product quality.

Rapid assessment and prediction of microbiological quality of raw milk using machine learning based on RGB-colourimetric resazurin assay

The feasibility of adapting an RGB-based colour sensor to determine raw milk quality based on the resazurin test was demonstrated and a model for rapid milk quality prediction proposed. One hundred and two raw milk samples containing different microbial concentrations were subject to a resazurin assay in a six-well microplate configuration and then to the colourimetric device to measure the resazurin test colours as red, green, and blue. A dataset of RGB colour measurements and corresponding microbial concentrations was created, from which a machine learning model for milk quality prediction was developed. A support vector machine model that was considered most suitable for this purpose demonstrated 100% prediction accuracy for milk with acceptable or “low” microbial concentrations (<5.0 × 105 cfu mL−1) and 96% accuracy for milk with unacceptable or “high” microbial concentrations (>1.0 × 107 cfu mL−1) but was less accurate for milk in the intermediate class.

Effects of thyme (Thymus vulgaris L.) essential oil supplementation on the microbiological quality of raw milk of lactating dairy cows

This study aimed to evaluate the supplementation of lactating cows with thyme (Thymus vulgaris L.) essential oil (TEO) on the centesimal composition and microbiological quality of raw milk. Twenty-four lactating cows (400±42.9kg initial body weight, 50±10days in milk, and 22.05±4.34kg/d milk production, second lactation) from an experimental farm in the region of Ribeirão Preto/SP, Brazil were used, divided randomly assigned to two groups: Control- 8mL/d soybean oil (as placebo), and Treatment- 8mL/d TEO, per cow/day. Both oils were offered encapsulated and administered daily via esophageal tube, for 21days. On d 21, milk was collected from each animal, fractionated into 50mL bottles. The microbiological quality of the raw was analyzed for standard plate count (SPC), milk composition (protein, fat, lactose, and solids non fat (SNF)), and thymol concentration. The treated group had significantly lower mean values for SPC after 168h under refrigeration, and no differences were observed in the milk composition. The supplementation of lactating dairy cows with 8mL/d TEO represents a promising alternative to controlling microbial spoilage in raw milk, allowing the reduction of economic losses in the milk chain, in addition to providing consumers with a safer product. However, further research should be conducted to better assess the effect of TEO supplementation on milk quality, such as sensory and toxicity studies, in addition to evaluating the effect of milk processing on oil activity and the effect on consumer health.

Tracking microbial quality, safety and environmental contamination sources in artisanal goat cheesemaking factories

A harmonised microbiological survey was performed in two artisanal factories of raw goat milk cheeses (A and B) located in the Andalusian region (Spain). A total of 165 different control points or samples (raw materials, final products, food-contact surfaces [FCS], and air) were examined as microbial and pathogen sources of contamination of artisanal goat raw milk cheeses. For raw milk samples analysed from both producers, the concentrations of aerobic-mesophilic bacteria (AMB), total coliforms, coagulase-positive Staphylococcus spp. (CPS), lactic-acid bacteria (LAB) and moulds and yeasts ranged between 3.48 and 8.59, 2.45–5.48, 3.42–4.81, 4.99–8.59 and 3.35–6.85 log cfu/mL respectively. For the same microbial groups, the analysis of raw milk cheeses revealed concentrations ranging from 7.82 to 8.88, 2.00–6.82, 2.00–5.28, 8.11–9.57 and 2.00–5.76 log cfu/g, respectively. Although the raw material analysed from producer A presented higher microbial loads and between-batch variability, it was B the producer with the most loaded final products. Regarding the microbial air quality, the fermentation area, storage room, milk reception and packaging room were the most AMB loaded places, while the ripening chamber was the area with higher fungal loads in bioareosol from both producers. Conveyor belts, cutting machine, storage boxes and brine tank were highlighted as the most contaminated FCS evaluated. Staphylococcus aureus was the only pathogen detected within the set of 51 isolates from samples as revealed by MALDI-TOF and molecular PCR, with a prevalence of 12.5% for samples from the producer B. The public health risk attributed to the consumption of artisanal goat cheese should not be neglected, and may consider the whole cheesemaking processing chain, from microbiological quality of raw milk to the ready-to-eat final product, especially concerning the presence of S. aureus.

Effect of Adding Propolis on Quality Standards of Raw Milk and Yoghurt

Food additives spread around the world may have potentially harmful effects; Propolis is considered a natural additive that meets the increasing demand for natural antioxidants and antimicrobials in place of synthetic preservatives. Different concentrations of water extract of Propolis (WEP) were assessed; the pH and microbiological quality of raw milk were evaluated, as well as the quality characteristics and bioactives in manufactured yoghurt. WEP 20% was the best concentration compared to WEP 5% and 10% and exhibited an acceptable pH value of milk for 48 hours. The addition of increased concentrations of WEP 20% (1, 2, and 3%) resulted in a significant decrease and gradual reduction of the total bacterial, coliform, yeast, and mold counts compared to the control group. Propolis-supplemented yoghurt had higher pH values than the control group. Yoghurt groups treated with 1% and 2% WEP achieved the highest scores and significantly different (P&lt;0.05) with control and 3% WEP groups in sensory examination until the end of the storage period. Furthermore, the counts of yeast and mold progressively decreased with the addition of higher concentrations of WEP throughout the storage period as 2%, 3% WEP groups were significantly different (P&lt;0.05) with control and 1% WEP groups. The total phenolic, flavonoid content and antioxidant activity of yoghurt treated with WEP were improved and significantly different (P&lt;0.05) compared to the untreated group. In conclusion, the raw milk and yoghurt preserved with propolis improved the quality of milk and increased bioactivity and nutritional benefits of yoghurt by elevating its antioxidant capacity. As a consequence, the produced yoghurt in our study proved that it is an acceptable product with functional, probiotic potential and has health-promoting properties that might be commercialized.

Prevalence Of Escherichia Coli and Staphylococcus Aureus in Raw Milk and its Products Sold for Human Consumption in Maiduguri, Northeastern Nigeria: A Potential Public Health Concern

Globally, milk represents an important human nutrition. However, it also serves as an important vehicle for transmission of foodborne pathogens some of which may be multidrug resistant. The current study was undertaken with the main aim of assessing the microbiological quality of raw milk and its products consumed in Maiduguri metropolis. Fresh milk was sampled from six different milk source outlets in the metropolis and the samples were subjected to standard microbiological procedures for the detection of Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). A cross-sectional study was conducted with a total of 120 milk samples collected and cultured on appropriate growth and differential media and further biochemical tests were carried out in order to determine the presence of E. coli and S. aureus. A total of 66 (55.0%) of the 120 samples were contaminated with bacteria, while 54 (45.0%) milk samples tested were negative for the contaminants. Contaminating bacteria comprised 51 (42.5%) and 43 (35.8%) of S. aureus and E. coli respectively. The mean pH of the milk samples ranges from 3.3 to 6.3 respectively in ―Kindirmo‖ and fresh milk with an overall mean pH of 3.9. A high prevalence of both pathogens was detected in ―Kindirmo‖ and ―Nono‖ fermented milk products. Overall, a statistically significant association was found between the detection of Escherichia coli (p = 0.046) and Staphylococcus aureus (p = 0.013) with the different types of milk samples examined. Our findings of the high prevalence of these pathogens in readily consumed fresh milk and its products in the study area raise public health concerns. Therefore, we recommended the application of strict quality control and good hygienic standards along the milk value chain by application of hazard analysis and critical control points (HACCP). Public health awareness of the health risks associated with the consumption of contaminated milk or its products is also highly recommended.

Assessment of Foodborne Bacterial Pathogens in Buffalo Raw Milk Using Polymerase Chain Reaction Based Assay.

Milk is a putrescible commodity that is extremely prone to microbial contamination. Primarily, milk and dairy products are believed to be easily contaminated by pathogenic microorganisms, including Listeria monocytogenes, Salmonella spp., and Staphylococcus aureus. The microbiological quality of raw milk and dairy products regarding foodborne pathogens is of paramount importance due to concern of human health. In this study 400 buffalo raw milk samples were screened for assessing the prevalence of L. monocytogenes, Salmonella spp., and S. aureus. This study implemented uniplex-polymerase chain reaction (u-PCR) and multiplex-polymerase chain reaction (m-PCR) assays for the fast simultaneous detection of these pathogens comparing to the conventional culturing methods. Raw milk samples were found contaminated with the prevalence of 2.2%, 4.0%, and 14.2% for L. monocytogenes, Salmonella spp., and S. aureus, respectively. These pathogens were detected with the optimized polymerase chain reaction assays after 6 h of enrichment. u-PCR and m-PCR demonstrated the limit of detection as 104, 102, and 10 cells/mL after 6, 12, 18, and 24 h for each culture of the pathogens. A high sensitivity (10 colony-forming unit [CFU]/mL) of the m-PCR protocol was noted. The developed protocol is a cost-effective and rapid method for the simultaneous detection of pathogens associated with raw milk and dairy industries.

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.

Prevalence and antimicrobial resistance in Streptococcus agalactiae isolated from raw milk in Pasuruan and Lumajang districts, East Java, Indonesia

Abstract. Permatasari DA, Anggraeni F, Budiarto, Meles DK, Hamid IS, Puspitasari Y, Effendi MH, Khairullah AR, Wardhana DK, Ugbo EN. 2022. Prevalence and antimicrobial resistance in Streptococcus agalactiae isolated from raw milk in Pasuruan and Lumajang districts, East Java, Indonesia. Biodiversitas 23: 5050-5055. Milk and dairy products are nutritionally important in the diet worldwide. The microbiological quality of raw milk is essential for the quality of the final dairy product. The presence of Streptococcus agalactiae is frequently associated with high somatic cell counts in milk and decreased milk yield. Streptococcus agalactiae infections have major consequences for public health. This study aimed to identify the prevalence and antimicrobial resistance of Streptococcus agalactiae isolated from raw milk in Pasuruan and Lumajang, East Java, Indonesia. Raw milk samples were collected from three sub-districts in Pasuruan (Tutur, Grati and Purwosari) and three sub-districts in Lumajang (Senduro, Karangbendo, and Tekung). California mastitis test (CMT) was performed to confirm the presence of somatic cells, S. agalactiae was identified using standard microbiological methods, and antibiotic resistance was determined by Kirby-Bauer disc diffusion method using Mueller-Hinton agar. Results showed that 89 (79.46%) out of 112 dairy cows were positive for CMT, which indicated the presence of mastitis. Bacteria isolation was performed on CMT-positive samples and four samples were showed the presence of S. agalactiae (4.49%). Based on the sensitivity test against various antibiotics, it was observed that S. agalactiae isolates were resistant to ampicillin (75%), and erythromycin (50%), and were sensitive to cefotaxime (100%), tetracycline (75%), and chloramphenicol (100%). This research reported that Streptococcus agalactiae organism is one bacterium that is implicated in mastitis infections. Therefore, monitoring the antibiotic susceptibility profiles of this organism is needed in veterinary medicine, in order to make an appropriate choice of drug for treatment, improve high cure rates and minimize the increase of drug resistance.

Assessment of Microbiological Quality of Raw Milk and Identification of Pathogenic Bacteria

Milk contains important nutrients such as minerals, vitamins, proteins and lipids and are consumed by all age group of humans around the world. It is impossible to avoid contamination of milk with micro-organisms because presence of nutrients therefore quality of milk can be determined by the microbial content in milk. Objective: To investigate the microbiological quality of raw milk. Methods: In the present study, there were 30 cow milk samples collected from different dairy farms of Lahore. Firstly, a surf field mastitis test was performed for detection of clinical and sub-clinical mastitis. The microbial isolation was performed by microbial culturing and biochemical tests and antibiotic sensitivity test was performed for isolated bacteria. These isolated bacterial DNA was extracted and amplified by 16S rRNA PCR. The precipitated amplicon was sequenced by 16S rRNA sequencing. The results were evaluated statistically to check the level of significance among them. Results: The Chi-square values of catalase test, oxidase test, indole test, methyl red test, Voges Proskauer test and triple sugar iron were 12.42, 13.77, 8.77, 9.02, 10.67 and 4.29 respectively and the p-values were 0.034, 0.031, 0.042, 0.039, 0.044 and 0.056 respectively on MacConkey Agar. The Chi-square values of catalase test, oxidase test, indole test, methyl red test, Voges Proskauer test and triple sugar iron were 12.44, 11.98, 9.38, 7.02, 14.22 and 10.43 respectively and p-values were 0.034, 0.045, 0.039, 0.012, 0.022 and 0.053 receptively on Mannitol salt Agar. The Chi-square and p-values of gram staining bacteria were 13.99 and 0.034 respectively and showed the significant relationship among them. Mastitis test were presented the value of Chi-square 17.86 and p-value 0.029. The ANOVA table on DNA isolation method were exposed the highly significant relationship among the variables. Conclusions: There was a significant association between different treatments. Different pathogens can grow in milk and milk products and produce toxic metabolites. Products that are contaminated by these toxic metabolites when consumed may results in food poisoning

An Overview of On-Farm Hygienic Milk Production

- The dairy sector has adopted hazard analysis of critical control points (HACCP) systems to ensure the food safety of dairy products. Through a chain management strategy, this allows for quality verification of final goods (European Commission, 2004b). Raw milk's quality and safety are critical for milk and the dairy products' safety and quality. Milk contamination with bacteria, chemical residues, and other pollutants affects the safety and quality of the products. Microbial contamination is the subject of this chapter. Salmonella spp, Listeria monocytogenes and Campylobacter jejuni are examples of human microbial pathogens discovered in raw milk. A very high microbiological quality of raw milk is essential for preventing process losses and achieving an optimum shelf life for dairy products, in addition to its importance for the public health. For example, faults in semi-hard cheeses are caused by the spore formers of butyric acid bacteria in the raw milk, and raw milk contamination with Bacillus cereus bacteria reduces the shelf life of pasteurized dairy products. Quality assurance methods for dairy farms are being created, and bacteriological structures are being used in farms bulk of raw milk payment systems, in order to guarantee that bulk tank milk has a high microbiological quality. Furthermore, dairy producers' sanitary milk production is critical for animal’s welfare and dairy industry's image. Infections of pathogenic microorganisms affect cows (e.g., udder tissue, gastrointestinal tract), resulting in lower milk production and even mortality. In conclusion, all components of the dairy production chain benefit from the management of the microbial ecology at the dairy farm, which leads to on-farm hygienic milk productions.

EFFECT OF COMMERCIAL AND ENVIRONMENTAL STARTER CULTURE ON THE QUALITY OF UNRIPENED RENNET CHEESE MADE FROM UNPASTEURIZED COW'S MILK

Background. The Polish cheese market is dominated by products made from pasteurized milk with commercial culture comprising microorganisms with genetically confirmed species affiliation. Current nutritional trends are focused on enriching the diet with natural products containing microorganisms characteristic of a given environment. Therefore, there is a need to look for ways to improve the quality of raw milk cheeses, which are characterized by a unique taste and aroma, as well as a large variety of lactic acid bacteria from a region. The aim of the study was to determine the quality of unripened rennet cheeses made from unpasteurized milk with two starter cultures: commercial and environmental. A microbiological analysis was carried out in order to: determine the total number of microorganisms, the number of mesophilic lactic acid bacteria, Escherichia coli and the presence of pathogens: Listeria monocytogenes and Salmonella spp. and staphylococcal enterotoxin. Results and conclusion. The microbiological quality of raw milk met the requirements for the total number of microorganisms laid down in the Regulation of the European Parliament and of the Council No. 853/2004, the Commission Regulation No. 2073/2005 (as amended). In cheeses produced using the environmental culture, the number of mesophilic LAB was significantly higher than in the other type of cheese. No pathogens or staphylococcal enterotoxin were detected in any of the products. During a sensory analysis of cheeses after production, it was found that they were very similar to each other in terms of overall acceptability. After 14 days of cheese storage, differences in sensory quality were found in favor of the products made using the environmental starter culture. All tested cheese samples met the requirements for microbiological safety.

Probabilistic modelling of Escherichia coli concentration in raw milk under hot weather conditions

Climate change is one of the threats to the dairy supply chain as it may affect the microbiological quality of raw milk. In this context, a probabilistic model was developed to quantify the concentration of Escherichia coli in raw milk and explore what may happen to France under climate change conditions. It included four modules: initial contamination, packaging, retailing, and consumer refrigeration.The model was built in R using the 2nd order Monte Carlo mc2d package to propagate the uncertainty and analysed its impact independently of the variability. The initial microbial counts were obtained from a dairy farm located in Saudi Arabia to reflect the impact of hot weather conditions. This country was taken as representative of what might happen in Europe and therefore in France in the future due to climate change. A large dataset containing 622 data points was analysed. They were fitted by a Normal probability distribution using the fitdistrplus package. The microbial growth was determined across various scenarios of time and temperature storage reflecting the raw milk supply-chain in France. Existing growth rate data from literature and ComBase were analysed by the Ratkowsky secondary model. Results were interpreted using the nlstools package.The mean E. coli initial concentration in raw milk was estimated to be 1.31 [1.27; 1.35] log CFU/ mL and was found to increase at the end of the supply chain as a function of various time and temperature conditions. The estimations varied from 1.73 [1.42; 2.28] log CFU/mL after 12 h, 2.11 [1.46; 3.22] log CFU/mL after 36 h, and 2.41 [1.69;3.86] log CFU/mL after 60 h of consumer storage. The number of milk packages exceeding the 2-log French hygiene criterion for E. coli increased from 10% [8;12%] to 53% [27;77%] during consumer storage. In addition, the most significant factors contributing to the uncertainty of the model outputs were identified by running a sensitivity analysis. The results showed that the uncertainty around the Ratkowsky model parameters contributed the most to the uncertainty of E. coli concentration estimates.Overall, the model and its outputs provide an insight on the possible microbial raw milk quality in the future in France due to higher temperatures conditions driven by climate change.

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.

Assessment of microbiological quality of raw milk produced and commercialized around INES Ruhengeri, Musanze district, Rwanda

Assessment of microbiological quality of raw milk produced and commercialized around INES Ruhengeri, Musanze district, Rwanda

Quality of raw milk in the highland tropics of Nariño, Colombia

Introduction. The production and commercialization of raw milk in Nariño, Colombia, follows microbiological and compositional standards on which payment for quality is made. However, quality can be affected during its transport after milking. Objective. To describe the microbiological and compositional quality of raw milk in the highland tropic. Materials and methods. The study was carried out in seven municipalities in the department of Nariño, Colombia, during the rainy season between February and July of 2017. Two milk samples from the same milk can were collected, one after milking (farm; n = 10), and the second at the collection point (tank; n = 10). In each sample, the following variables were evaluated: height above the sea level of the collection site, aerobic mesophilic count (CFU), total coliform count (COL), milk temperature, fat (FAT), protein (PC) and total solids (TS). Results. The temperature of the milk was higher on the farm compared to the tank (30±0.68 vs. 23±0.87 °C, respectively). The aerobic mesophilic count was higher in the tank vs. farm (116,470 vs. 41,388 CFU ml-1, respectively). The temperature of the milk was negatively correlated with the distance and the transport time of the milk (-0.86 and -0.84, respectively). The compositional quality of the milk was not affected by transport conditions. Conclusion. In the high tropic conditions, the microbiological quality of raw milk was negatively affected by the increase in the aerobic mesophilic counts.

Rapid Microbiological Assessment in Raw Milk: Validation of a Rapid Alternative Method for the Assessment of Microbiological Quality in Raw Milk.

The consumption of dairy products and the dairy industry are one of the main global agri-food sectors for its size, economic importance, and level of technology. Microbiological quality of pasteurized milk or other milk products is dependent on microbiological quality of raw milk. A variety of microbiological count methods is available for monitoring the hygienic quality of raw milk. Among them, the pour plate method is the official essay for counting the number of colony-forming units in milk samples according to International Organization for Standardization (ISO) No. 4833-1:2013. The aim of the present study is the validation of the Micro Biological Survey (MBS) method, against the reference plate-count method, for the assessment of the microbiological quality of raw milk. This comparative study, performed in collaboration with the Istituto Zooprofilattico Sperimentale del Lazio e della Toscana M. Aleandri (IZSLT), demonstrates the accuracy of this alternative method for the determination of total viable bacterial count in cow’s raw milk. The results obtained with the MBS method highlight its potential as a valid tool for reliable microbiological analysis in dairy industries.