CONTRIBUTION TO THE DEBATE ON THE MICROBIOLOGICAL QUALITY OF RAW MILK FROM VENDING MACHINES

Purpose The purpose of this paper is to study the microbiological quality of raw milk delivered by 17 vending machines (VM) owned by different Slovenian milk producers. Design/methodology/approach For the determination of hygiene-technical conditions of VM, an observation list that included criteria for estimation of hygiene-technical suitability was made. A total of 51 milk samples were collected in three different seasons. The swabs and the cleaning liquid (eluates) of dispensing nozzles and chambers were also sampled. The main groups of microorganisms were determined by colony count technique according to international standards in all collected samples. Findings The aerobic colony count was higher than 100,000 CFU/mL in 20 (39.2 per cent) of milk samples. Its mean value was 4.8 log10 CFU/mL. The mean values of Enterobacteriaceae, psychrotrophic microorganisms, lipolytes, proteolytes, yeasts and moulds together, coagulase-positive staphylococci and somatic cell count were 3.3 log10 CFU/mL, 4.1 log10 CFU/mL, 3.2 log10 CFU/mL, 3.9 log10 CFU/mL, 2.2 log10 CFU/mL, 2.8 log10 CFU/mL and 5.3 log10 cells/mL, respectively. E. coli was found in 33.3 per cent of milk samples, while Listeria monocytogenes and antibiotics were not detected. The inner surface contamination of the dispensing nozzles and chambers was estimated in the range from 1.8 log10 CFU to 6.0 log10 CFU/cm2. The presence of detergents and disinfectants in supply valve eluates was determined in more than one-third of the samples. The hygienic-technical conditions of observed VM show some deviations from specified hygienic-technical requirements which could influence the safety of raw milk. Research limitations/implications The data about construction and the cleaning practice of VM, included in the experiment, were not available during the inspection facility. Originality/value In the paper the pathogenic and also the spoilage microorganisms in milk in the combination with hygienic conditions of inside surfaces of VM were studied.

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

International Journal of Veterinary Science ◽

10.37422/ijvs/20.060 ◽

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.

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

Semina Ciências Agrárias ◽

10.5433/1679-0359.2019v40n4p1469 ◽

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.

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

Bangladesh Journal of Veterinary Medicine ◽

10.3329/bjvm.v6i2.2339 ◽

1970 ◽

Vol 6 (2) ◽

pp. 217-221 ◽

Cited By ~ 3

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 Â doi: 10.3329/bjvm.v6i2.2339 Bangl. J. Vet. Med. (2008). 6 (2): 217-221

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

Journal of Food Protection ◽

10.4315/0362-028x-59.9.984 ◽

1996 ◽

Vol 59 (9) ◽

pp. 984-987 ◽

Cited By ~ 4

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.

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

Journal of Food Protection ◽

10.4315/0362-028x-50.8.665 ◽

1987 ◽

Vol 50 (8) ◽

pp. 665-668 ◽

Cited By ~ 12

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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