Hygienic Conditions and Microbial Contamination in Six Ewe's-Milk-Processing Plants in Sardinia, Italy

1997 ◽  
Vol 60 (3) ◽  
pp. 283-287 ◽  
Author(s):  
SOFIA COSENTINO ◽  
FRANCESCA PALMAS
Keyword(s):  
Microbial Contamination ◽  
Microbiological Quality ◽  
Raw Milk ◽  
Raw Material ◽  
Processing Conditions ◽  
Technological Parameters ◽  
Milk Processing ◽  
Processing Plants ◽  
Ewe's Milk

In Sardinia, ewe's milk is almost exclusively used for cheese manufacture, and it is usually processed in small dairies which do not have sufficient technical and scientific knowledge for largescale controlled production. This study was carried out to identify the sources of contamination and the kinds of contaminating microorganisms present in six ewe's milk processing plants in Sardinia. Samples were collected during production hours three times over a period of 6 months. Raw milk, heat-treated milk, curd, 30-day-old cheese, lactic culture, rennet, and water used in processing lines were analyzed and the microbial contamination of air and surfaces was evaluated. Total mesophilic aerobic counts, coliforms, Escherichia coli, gram-negative psychrotrophs, Staphylococcus aureus, Salmonella spp., Listeria spp., yeasts, and molds were determined. Our survey confirmed that the production offood of high microbiological quality is strictly dependent on the microbiological quality of the raw material, optimization of the parameters for the heat treatment, water of potable quality, well-defined cleaning and disinfection procedures, and properly hygienic processing conditions. In fact, only plants characterized by raw milk and rennet of acceptable quality, generally clean work surfaces, and low microbial counts in the air of working areas made finished products of high microbiological quality. Standardization of technological parameters and achievement of properly hygienic processing conditions will help minimize the risk of developing food-safety problems, in compliance with public health regulatory requirements. These actions would help guarantee an adequate quality of Sardinian ewe's milk cheeses and might also lead to access to the international market.

scholarly journals Quality of raw milks in three milk processing plants in Cordoba

2014 ◽  
Vol 6 (1) ◽  
pp. 103 ◽  
Author(s):  
VIRGINIA RODRÍGUEZ, R. ◽  
ALFONSO CALDERÓN R. ◽  
OSCAR VERGARA G.
Keyword(s):  
Physicochemical Parameters ◽  
Microbiological Quality ◽  
Raw Milk ◽  
Fecal Coliforms ◽  
Processing Plant ◽  
Normal Range ◽  
Dual Purpose ◽  
Milk Processing ◽  
Processing Plants

An important condition in dairy processing plant is to obtain materials of excellent physicochemical and microbiological quality to reduce public health risks. High counts of mesophilic show contamination and lack of good manipulation in milking and milk conservation. Coliforms are a demonstration of contamination with fecal material. The norms in Colombia establish the mesophilic count as standard of microbiological quality. The purpose of this study was to determine the physicochemical and microbiological quality and health of the udders, in raw milk from dual purpose farms, supplying three milk processing plants in Cordoba (Colombia). 149 raw milk samples were collected of tree processing plants in Cordoba department. Physicochemical parameters set out in Decree 616 of 2006 were determined and aerobic mesophilic, total coliforms, fecal coliforms, and somatic cell count were established too. The variables obtained were analyzed by descriptive statistics using SAS. The physicochemical parameters were within the normal range but averages of mesophilic and somatic cells counts were high, which allows conclude that the physicochemical quality is good, but there are shortcomings in the microbiological quality and in the udder health, and is on the farms devoted to milk production where must be implemented and certified excellent management and prevention practices.

scholarly journals Microbiological quality of refrigerated raw milk in the dairy farm and after transport to the processing dairy plant

2018 ◽  
Vol 84 (0) ◽  
Author(s):  
Vivian Mörschbächer ◽  
Claudete Rempel ◽  
Mônica Maciel
Keyword(s):  
Low Temperatures ◽  
Microbiological Quality ◽  
Dairy Farm ◽  
Raw Milk ◽  
Raw Material ◽  
Processing Plant ◽  
Milk Samples ◽  
Dairy Plant ◽  
The Mean

ABSTRACT: Transport of cooled raw milk in bulk has greatly improved the quality of the raw material collected by dairy plants as it reduces the proliferation of mesophilic microorganisms that cause milk acidity and hinder its processing. However, refrigeration has favored the growth of psychrotrophic microorganisms which are able to grow at low temperatures (below 10ºC) and that produce heat resistant enzymes which degrade some milk components, reducing milk shelf life and causing organoleptic changes. The aim of this paper was to evaluate the microbiological quality of raw milk in dairy farms and after its transport to the processing dairy plant, through plate counting of mesophilic and psychrotrophic microorganisms. Fourteen milk samples were collected from tanks of the dairy-farming properties, and one sample was collected from their milk transport tanker at the entrance of the processing plant. Our results showed that the mean number of mesophilic microorganisms was higher in samples collected straight from the dairy farm tanks than in the samples collected from the transportation tankers at the entrance of the plant. Of the 14 sampled tanks, 64.3% were non-compliant with legislation. The sample collected from the milk transportation tanker containing milk from all properties showed a higher mean number of psychrotrophic microorganisms than the dairy farm samples. We conclude that the milk from dairy properties showed a higher amount of mesophilic microorganisms, and after transportation, at the entrance of the processing plant, there is a higher amount of psychrotrophic microorganisms.

Impact of Raw Materials and Processing Techniques on The Microbiological Quality of Egyptian Domiati Cheese

2020 ◽  
Keyword(s):  
Raw Materials ◽  
Microbiological Quality ◽  
Raw Milk ◽  
Plate Count ◽  
E Coli ◽  
Fresh Cheese ◽  
Processing Techniques ◽  
The Impact ◽  
Total Yeast

Domiati cheese is the most popular brand of cheese ripened in brine in the Middle East in terms of consumed quantities. This study was performed to investigate the impact of the microbiological quality of the used raw materials, the applied traditional processing techniques and ripening period on the quality and safety of the produced cheese. Three hundred random composite samples were collected from three factories at Fayoum Governorate, Egypt. Collected samples represent twenty-five each of: raw milk, table salt, calf rennet, microbial rennet, water, environmental air, whey, fresh cheese, ripened cheese & swabs from: worker hands; cheese molds and utensils; tanks. All samples were examined microbiologically for Standard Plate Count (SPC), coliforms count, Staphylococcus aureus (S. aureus) count, total yeast & mould count, presence of E. coli, Salmonellae and Listeria monocytogenes (L. monocytogenes). The mean value of SPC, coliforms, S. aureus and total yeast & mould counts ranged from (79×102 CFU/m3 for air to 13×108 CFU/g for fresh cheese), (7×102 MPN/ cm2 for tank swabs to 80×106 MPN/ml for raw milk), (9×102 CFU/g for salt to 69×106 CFU/g for fresh cheese) and (2×102 CFU/cm2 for hand swabs to 60×104 CFU/g for fresh cheese), respectively. Whereas, E. coli, Salmonella and L. monocytogenes failed to be detected in all examined samples. There were significant differences in all determined microbiological parameters (p ≤0.05) between fresh and ripened cheese which may be attributed to different adverse conditions such as water activity, pH, salt content and temperature carried out to improve the quality of the product.

Molecular Subtyping and Characterization of Psychrotolerant Endospore-Forming Bacteria in Two New York State Fluid Milk Processing Systems

2007 ◽  
Vol 70 (10) ◽  
pp. 2354-2364 ◽  
Author(s):  
JASON R. HUCK ◽  
NICOLE H. WOODCOCK ◽  
ROBERT D. RALYEA ◽  
KATHRYN J. BOOR
Keyword(s):  
Control Strategies ◽  
New York State ◽  
Raw Milk ◽  
Effective Control ◽  
Processing Plant ◽  
Milk Processing ◽  
High Temperature Short Time ◽  
Processing Plants ◽  
Processing Continuum ◽  
Fluid Milk

Psychrotolerant endospore-forming bacteria Bacillus and Paenibacillus spp. are important spoilage organisms in fluid milk. A recently developed rpoB subtyping method was applied to characterize the diversity and phylogenetic relationships among Bacillus and related sporeformers associated with milk processing systems. Milk samples representing the processing continuum from raw milk to pasteurized products were collected from two fluid milk processing plants, held at 6°C uptothe code date that had been established by each processing plant (i.e., either 18 or 21 days), and plated for bacterial enumeration throughout storage. Bacterial colonies selected to represent the visible diversity in colony morphology on enumeration plates were examined further. Among 385 bacterial isolates characterized, 35% were Bacillus spp., and 65% were Paenibacillus spp. A total of 92 rpoB allelic types were identified among these isolates, indicating considerable diversity among endospore-forming spoilage organisms present in fluid milk systems. Of the 92 allelic types identified, 19 were isolated from samples collected from both processing plants. The same rpoB allelic types were frequently identified in paired raw milk and packaged product samples, indicating that Bacillus and Paenibacillus spp. can enter dairy processing systems through raw milk. Certain subtypes were found exclusively in pasteurized samples, including those that were temporally independent, suggesting the possibility of in-plant sources for these spoilage organisms, including through the persistence of selected subtypes in processing plants. Development of effective control strategies for the diverse array of psychrotolerant endospore-forming organisms that currently limit the shelf lives of high-temperature short-time fluid milk products will require comprehensive, integrated efforts along the entire milk processing continuum.

scholarly journals Microbial quality of beef and hygiene practices in small and medium slaughterhouses and butcheries in Uganda

2020 ◽  
Author(s):  
Juliet Kyayesimira ◽  
Wangalwa Rapheal ◽  
Grace Kagoro Rugunda ◽  
Lejju Julius Bunny ◽  
Morgan Andama ◽  
...  
Keyword(s):  
Microbial Contamination ◽  
Microbiological Quality ◽  
Microbial Load ◽  
Microbial Quality ◽  
E Coli ◽  
Hygiene Practices ◽  
Safe Level ◽  
Microbiological Methods ◽  
Beef Carcass

Abstract Background If hygiene practices along the beef processing nodes at small and medium enterprise (SME) slaughter houses and butcheries are not observed, they may pose a health risk due to microbial contamination. In SME slaughterhouses and butcheries, the risk may be higher due to transmission of foodborne pathogens. This study determined the hygienic practices and microbial quality risk among meat handlers (MH) in SME slaughterhouses and butcheries. Methods Assessment of microbiological quality of beef was carried out at slaughter houses and butcher shops in the districts of Western, Central and Eastern regions of Uganda. A cross sectional study was conducted from June 2017 to January 2018 using observation checklists to record unhygienic practices among the various actors. Microbial load at slaughter and butchery was determined from a total of 317 swab samples collected from carcass, tools, protective clothing and hands of meat handlers. The microbiological quality of beef was evaluated using standard microbiological methods. The samples were inoculated into differential and selective media. Results Butcheries had the highest microbial load on beef carcass ranging from 4.76 log 10 cfu/cm 2 to 7.90 log 10 cfu/cm 2 Total Viable Counts (TVC) while Total Coliform Counts (TCC) ranged from 1.42 log 10 cfu/cm 2 to 3.05 log 10 cfu/cm 2 , E. coli ranged from 0.68 log 10 cfu/cm 2 to 1.06 log 10 cfu/cm 2 and Staphylococcus aureus ranged from 3.25 log 10 cfu/cm 2 to 4.84 log 10 cfu/cm 2 . Salmonella was absent in all the samples analysed. Results of overall microbial quality of beef in Uganda indicated that only TCC (1.60±0.26 log 10 cfu/cm 2 ) of the beef carcass samples at slaughter houses was not significantly above the safe level (p = 0.693). Overall microbial load (TVC, TCC, E. coli and S. aureus ) at butcheries were significantly (p < 0.05) above the safe level. Butcheries of Mbale district had the highest percentage (70%) of beef carcass samples above the TCC safe levels whereas butcheries of Mbarara district had the highest percentage (40%) of beef carcass samples above the E. coli safe levels. TVC from hands and clothes at butchery across the three study districts varied significantly (p=0.007) with the highest counts (7.23 log 10 cfu/cm 2 ) recorded from personnel clothes and lowest (5.46 log 10 cfu/cm 2 ) recorded from hands. On the other hand, swab samples picked from chopping board and working table at the butchery did not show significant variation in TVC, TCC, E. coli and S. aureus microbial loads across the three study districts. Conclusion Hygienic handling of carcasses after slaughter is critical in preventing contamination and ensuring meat safety in informal meat trading sectors in Uganda. Handling practices of beef at Ugandan slaughterhouses and butcheries are not hygienic hence not up to standard and they contribute to microbial contamination of beef posing a risk to consumers. The distribution stage is the most critical period, during which the quality of meat can easily be compromised.

Improving the quality of raw milk and yogurt

2021 ◽  
pp. 49-57
Author(s):  
T. V. Ananyeva ◽  
V. I. Ostroukhova
Keyword(s):  
Electromagnetic Radiation ◽  
Raw Materials ◽  
Educational Institution ◽  
Raw Milk ◽  
Negative Influence ◽  
Raw Material ◽  
Federal State ◽  
Expert Assessment ◽  
Microbiological Safety

Milk is a part of many food products. In the expert assessment of the quality of raw materials, primary attention should be paid to its microbiological safety, since poisoning with dairy products is a common cause of diseases of the gastrointestinal tract. The experiment has been carried out on the base in the Teaching and Production Livestock Farm in the Federal State Budgetary Educational Institution of Higher Education “Russian State Agrarian University – Moscow Agricultural Academy named after K. A. Timiryazev” (Moscow). The purpose of the research was to improve the quality indicators of raw milk and yogurt. The method of processing raw milk, which reduces the number of potentially dangerous microorganisms in the products produced from it, has been studied. During the experiment the influence of electromagnetic radiation on organoleptic and physic and chemical parameters has been observed; the quantitative and qualitative composition of milk and yogurt microorganisms has been evaluated. The samples of raw materials had a uniform consistency without sediment and flakes, the color was milky white, and the smell was characteristic of natural cow’s milk. Electromagnetic treatment did not affect the main elements of the chemical composition of milk: the mass fraction of dry substances, fat, protein and lactose. In the experimental samples of raw milk after electromagnetic pulses treatment, the decrease in the growth rate of microorganisms including Quantity of Mesophilic Aerobic and Facultative Anaerobic Microorganisms (QMAFAnM), yeast and mold, has been noted. No bacteria of the Staphylococcus aureus and Escherichia coligroups have been found in the milk samples. The electromagnetic field had the negligible effect on the amount of lactic acid microorganisms in the raw material. During the experiment, there was no negative influence of electromagnetic radiation on the organoleptic, physic and chemical and sanitary-hygienic parameters of yogurt. The issues of ensuring the microbiological safety of raw milk have been described and the method for optimizing the sanitary and hygienic parameters of yogurt in accordance with the current requirements of regulatory documents has been suggest in the article.

scholarly journals Influence of the microbiological quality of raw milk on the shelf life of pasteurized milk

2019 ◽  
Vol 40 (4) ◽  
pp. 1469
Author(s):  
José Carlos Ribeiro Júnior ◽  
Aline Marangon de Oliveira ◽  
Fernando Godoi Silva ◽  
Lorena Natalino Haber Garcia ◽  
Cátia Maria de Oliveira Lobo ◽  
...  
Keyword(s):  
Shelf Life ◽  
Microbiological Quality ◽  
Raw Milk ◽  
Poor Quality ◽  
Pasteurized Milk ◽  
Microbial Counts ◽  
Legal Standards ◽  
Milk Samples ◽  
Brazilian Standard

The dairy industry strives to produce high quality products with high nutritional value as well as to meet the legal standards for longer shelf life. However, these goals are made unfeasible by the poor quality of raw milk produced in some regions of Brazil. Others Brazilian dairy regions, however, already succeed in producing milk with low microbial counts, such as the municipality of Castro, Paraná state, designated as the ‘Brazilian dairy capital’. In order to evaluate the effect of raw milk quality on microbial counts during the shelf life of pasteurized milk, samples were collected from two dairy regions of Paraná: the northern and Castro region, characterized by milk production with high and low microbiological counts, respectively. Samples were experimentally pasteurized and the total microorganism counts were analyzed for 18 days at 7°C, using the Brazilian standard microbiological count limit for pasteurized milk (8 x 104 CFU/mL) as the end of the shelf life. Low microbiological counts in raw milk (Castro) resulted in significantly lower counts shortly after pasteurization and over the entire shelf life, meeting the pasteurized milk standard for 18 days. The temporal evolution in the counts over 18 days for the milks of high and low microbiological count was similar; however, the disparity between the absolute counts between the regions was significant (p < 0.05). Of the milk samples from northern Paraná, four (44.4%) already had counts higher than that of the legislative limit for pasteurized milk immediately after pasteurization. The others (five) reached the maximum microbiological count limit for pasteurized milk on the 6th day after pasteurization. In contrast, the milk from the Castro region remained below the limit throughout the analysis period. Thus, it can be stated that the microbiological quality of raw milk is directly related to the initial count of microorganisms after pasteurization, and that pasteurized milk produced from raw milk with low microbiological counts complies with the Brazilian legislation for 18 days following thermal processing.

scholarly journals Physical and microbial qualities of raw milk collected from Bangladesh Agricultural University dairy farm and the surrounding villages

1970 ◽  
Vol 6 (2) ◽  
pp. 217-221 ◽  
Author(s):  
MTG Khan ◽  
MA Zinnah ◽  
MP Siddique ◽  
MHA Rashid ◽  
MA Islam ◽  
...  
Keyword(s):  
Microbiological Quality ◽  
Dairy Farm ◽  
Raw Milk ◽  
Viable Count ◽  
Physical Parameters ◽  
Total Viable Count ◽  
Coliform Count ◽  
Milk Samples

The present study was undertaken with the aim of investigating the physical parameters (e.g. organoleptic and specific gravity of raw milk) and also to study the microbiological quality of raw milk (total viable count, Coliform count and Staphylococcal count) from different villages and Bangladesh Agricultural University (BAU) Dairy Farm of Mymensingh District of Bangladesh, during the period from July to November 2007. A total number of 100 raw milk samples were collected at morning and evening from BAU dairy farm and surrounding four villages of BAU campus. The organoleptic and bacteriological qualities of each sample were analyzed. The organoleptic examination included taste panel score to assess consumer's acceptance and the bacteriological analysis comprised enumeration of total viable count (TVC), total colifrom count (TCC) and total staphylococcal count (TSC) for the determination of sanitary quality. The organoleptic quality of the milk samples is more or less same except the Churkhai milk samples which had flat taste (in 16% milk sample). The average values of TVC/ml were log 5.920, 5.934, 6.007, 6.075 and 6.127 for BAU Dairy Farm, Boira, Shutiakhali, Churkahai and Paglabazar respectively; coliform count were log 2.501, 2.522, 2.550, 2.620 and 2.619 respectively; staphylococcal count were log 2.832, 2.812, 2.866, 2.931 and 2.988 respectively. So, it may be concluded that the raw milk samples of BAU Dairy Farm were superior to others collected from the selected villages which may be due to maintaining better hygienic condition. Key words: Raw milk, physical and microbial quality   doi: 10.3329/bjvm.v6i2.2339 Bangl. J. Vet. Med. (2008). 6 (2): 217-221

Chemical and Microbiological Quality of Raw Milk Produced by Smallholder Farmers in Zimbabwe

1996 ◽  
Vol 59 (9) ◽  
pp. 984-987 ◽  
Author(s):  
A. N. MUTUKUMIRA ◽  
S. B. FERESU ◽  
J. A. NARVHUS ◽  
R. K. ABRAHAMSEN
Keyword(s):  
Lactic Acid ◽  
Lactic Acid Bacteria ◽  
Smallholder Farmers ◽  
Microbiological Quality ◽  
Titratable Acidity ◽  
Raw Milk ◽  
Chemical Characteristics ◽  
Yeasts And Molds ◽  
Microbiological Analyses

Chemical and microbiological analyses were carried out on 10 samples of raw milk collected over 6 months from the Nharira/Lancashire Milk Collection Center. The milk center is run by smallholder farmers. The purpose of the study was to evaluate the quality of the raw milk delivered to the milk collection center. The average chemical characteristics of the milk were (%): titratable acidity expressed as lactic acid, 0.21; total protein, 3.19; fat, 3.52; total solids, 11.76; and solids not fat, 8.25; the pH varied from 6.15 to 6.65. There were large variations in the microbiological composition of the raw milk with total aerobic counts ranging from 6.2 × 103 to 7.8 × 107 CFU/ml, coli forms from 3.2 × 102 to 2.3 × 105, and lactic acid bacteria from less than 1 × 103 to 2.9 × 106 CFU/ml. Yeasts and molds were less than 100 CFU/ml in 7 of the 10 samples analyzed.

Impedance Measurement as an Alternative to the Plate Count Method for Estimating the Total Count of Bacteria in Raw Milk

1987 ◽  
Vol 50 (8) ◽  
pp. 665-668 ◽  
Author(s):  
F. F. J. NIEUWENHOF ◽  
J. D. HOOLWERF
Keyword(s):  
Standard Deviation ◽  
Microbiological Quality ◽  
Impedance Measurement ◽  
Raw Milk ◽  
Plate Count ◽  
Impedance Method ◽  
Count Method ◽  
Plate Counts ◽  
Plate Count Method

An improved impedance method is described with a good standard deviation of repeatability (sm = 0.05 log unit) and a fair standard deviation of the estimate of the plate count from the detection time [(sy)x = 0.33 log unit]. Compared with the standard deviation of repeatability of the plate count method (0.07 log unit), the standard deviation of repeatability of the impedance method described is a significant improvement. The impedimetric experiments were done with a Bactometer M123. The detection times as measured by this instrument were compared with the plate counts at 30°C for samples of raw refrigerated farm milk. With this technique a good indication of the microbiological quality of raw milk can be obtained within 15 h.

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