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

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.

1984 ◽  
Vol 47 (3) ◽  
pp. 177-181 ◽  
Author(s):  
T. G. REHBERGER ◽  
L. A. WILSON ◽  
B. A. GLATZ

A study was done to investigate the microbiological quality of commercial tofu available in local retail outlets. A sampling method was first developed to obtain accurate and representative microbial counts of individual pieces of tofu. Plate count determination of total aerobic organisms, psychrotrophs, coliforms, sporeformers, yeasts and molds, and staphylococci were made on 60 tofu samples (representing three lots each of four different brands) obtained within 24 h after delivery to the retail store. In addition, for two brands that provided manufacturer's pull dates, the same microbial counts were obtained for samples stored in the laboratory at 10°C until the pull date. Of the tofu sampled immediately after purchase, 83% of the lots tested had total counts greater than 106 colony-forming units (CFU)/g and psychrotrophic counts greater than 104 CFU/g. In addition, 67% of the lots tested had confirmed coliform counts greater than 103 CFU/g. Very low levels (less than 10 CFU/g) of all other microbial groups tested for were found in the majority of lots. Samples held until the manufacturer's pull date contained higher total and psychrotrophic counts but lower or stable counts of other organisms compared with samples tested immediately after purchase. To improve the microbiological quality of tofu, processors need to reduce initial loads by improving sanitation and processing techniques, and retailers should provide more consistent and colder refrigerated storage.


2008 ◽  
Vol 13 (4) ◽  
pp. 327 ◽  
Author(s):  
M. KOIVULA ◽  
H-R. KYMÄLÄINEN ◽  
L. VANNE

Linseed (Linum usitatissimum L.) and fi bre hemp (Cannabis sativa L.) can be used as raw materials in various applications. In this study, microbiological quality and meteorological measurements were made during the growing seasons and harvesting periods of 2001 and 2002. The microbiological analyses were carried out with Hygicult® TPC and Y&F dipslides, and with a surface spreading method using Plate Count and Potato Dextrose agars. During the growing season of 2001 the conditions were mostly humid, whereas the growing season of 2002 was rather dry and warmer than that of 2001. The lack of water during the growing season of 2002 affected the growth of the plants. In the case of both hemp and fl ax, the mould and bacterial contents (cfu gdw-1) increased markedly at the end of the growing season of 2001. During the growing season of 2002 the increase in mould and bacterial contents was noticeable but more constant throughout the whole growing season. At the end of the growing seasons, the mould and bacteria contents were higher in 2001 than in 2002. The genera of moulds identifi ed included Cladosporium, Fusarium, Penicillium, Mucor and Alternaria. The microbiological safety should be controlled during the whole production chain, beginning with the cultivation and harvesting periods.;


1987 ◽  
Vol 50 (8) ◽  
pp. 665-668 ◽  
Author(s):  
F. F. J. NIEUWENHOF ◽  
J. D. HOOLWERF

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.


2008 ◽  
pp. 67-75
Author(s):  
Ferenc Peles ◽  
Zsuzsa Máthéné Szigeti ◽  
Béla Béri ◽  
András Szabó

The importance of the quality of raw milk increased after Hungary had joined to the EU. On delivery of raw milk, the microbiological quality, especially total plate count of the milk is very important. Twenty-two farms (7 large, 4 medium-sized, and 11 small farms) were included in the study. We considered the different farm size, keeping- and milking circumstances during the selection of farms. The examined large farms use loose housing system (cubicle, deep litter) and milking parlour. Most of them use preand post-milking disinfection. In the medium-sized farms, loose,deep litter and tie-stall housing system, as well as milking parlour, pipeline milking and bucket milking occurred. All of them use preand post-milking disinfection. Small farms use tie-stall housing system, bucket milking and udder preparation by water. Unfortunately, they do not use pre- or post-milking disinfection. In the large and medium-sized farms mainly Holstein Friesian, in the small farms Hungarian Simmental breeds can be found.The aim of our research was to examine the microbiological status of the raw milk produced in dairy farms (total plate count, coliform count, Escherichia coli count, Staphylococcus aureus count, psychrotroph bacteria count, furthermore yeast and mold count); sources of the contamination; connection between the microbiological quality of produced milk and housing-, milking technologies of farms; furthermore the hygienic circumstances of milking and milk handling of the farms, by the examination of coliform bacteria and Escherichia coli contamination.During the examination of the connection between the different farm sizes, various housing- and milking forms and the microbiological characteristics we observed similar tendencies in the case of total plate count, coliform count, yeast and molds count, furthermore psychrotroph bacteria count. The value of  these parameters was significantly higher in small farms, and infarms which use tie-stall housing forms, bucket milking, udder preparation with water, and which do not use pre- and post-milking disinfection.The results showed that besides cooling, the milking procedure and the type of udder preparation had the largest effect on the total plate count. Statistical analysis shows that in medium and small farms the combination of pipeline milking – tie stall housing system – disinfectant preparation of the udder; in large farms the combination of milking parlour – loose cubicle housing system – dry preparation of the udder are the most appropriate in the aspect of the total plate count. We experienced that in farms where the hygienic instructions are not followed – and thereforeequipment used during the milking and handling of milk is very contaminated – or rather the separation of mastitic cows’ milk is not appropriate, different microorganisms may contaminate the produced milk. 


2016 ◽  
Vol 14 (3) ◽  
Author(s):  
Nur Zumairotul Muna ◽  
AT. Diana Nerawati ◽  
Rachmaniyah .

Crystal ice cube consumed by people is distributed through distribution chain from factories, agents, and ice traders in Surabaya. Each distribution chain posses risk of contamination to the quality of the ice, one of which is microbiological contamination that cause health problems to consumers. This is descriptive study aimed to obtain microbiological quality of crystal ice cube and hygiene sanitation throughout distribution chain in Surabaya. Sampling and observations were conducted sequentially in the same day, in different time and with 3 time repetition for 3 days in a row. Data were analyzed descriptively. The result showed  that the ice crystals did not contain E. coli yet contained MPN Coliform. The rate of MPN Coliform on ice at factory  was 10 colonies / 100 cc sample, at agent was 12-15 colonies / 100 cc sample, and at merchant were 15-43 colonies / 100 cc sample. Hygiene sanitation affecting MPN Coliform in crystal ice are non standard raw materials, production process, transportation, and the handlers. In conclusion, microbiological quality of crystal ice cube along the distribution chain in Surabaya with E. coli parameter did not meet standard. Health Department needs to conduct surveillance on a regular basis. Factory of ice cube needs to  make Standard Operating Procedures. Agents  and traders need to improve hygiene sanitation of conveyance, transport personnel, equipment, and handlers.  Keywords : Ice Cube Crystals, Chain Distribution, Hygiene Sanitation, MPN Coliform, E. coli


2006 ◽  
Vol 69 (5) ◽  
pp. 1113-1117 ◽  
Author(s):  
DAVID PHILLIPS ◽  
DAVID JORDAN ◽  
STEPHEN MORRIS ◽  
IAN JENSON ◽  
JOHN SUMNER

The third national baseline microbiological survey of Australian beef carcasses and frozen boneless beef was conducted in 2004. Carcasses (n = 1,155) sampled at 27 slaughter establishments had a mean aerobic plate count (at 25°C) of 1.3 log CFU/cm2. Escherichia coli was isolated from 8.0% of the carcasses, with a mean count of −0.8 log CFU/cm2 for positive samples. On samples from 24 boning (fabrication) plants (n = 1,082), the mean aerobic plate count for frozen boneless beef was 1.3 log CFU/g, and the mean count for the 1.8% of samples with detectable E. coli was 1.5 log CFU/g. E. coli O157: H7 was isolated from 1 of 1,143 carcasses and from 0 of 1,082 boneless samples. Salmonella was isolated from 0 of 1,155 carcasses and from 1 of 1,082 samples of boneless product. No Campylobacter spp. were isolated from carcasses or boneless beef. Coagulase-positive staphylococci were isolated from 28.7% of beef carcasses and 20.3% of boneless beef samples, and positive samples had a mean count of 0.3 log CFU/cm2 and 0.8 log CFU/g, respectively.


2012 ◽  
Vol 81 (1) ◽  
pp. 37-42 ◽  
Author(s):  
Irena Svobodová ◽  
Gabriela Bořilová ◽  
Radka Hulánková ◽  
Iva Steinhauserová

Microbial contamination of poultry carcasses can be influenced by many factors during transport and slaughtering. The aim of this study was to evaluate the impact of four processing steps (plucking, evisceration, washing and chilling) on the total viable counts (TVC), counts ofEscherichia coli,Salmonellaspp. andListeriaspp. incidence on broiler carcasses. A total of 160 broiler carcasses originating from one farm were collected during one year period at a Czech slaughterhouse and examined. Both TVC andE. colicounts decreased during processing from 4.6 log cfu/cm2and 3.5 log cfu/cm2to 3.7 log cfu/cm2and 1.8 log cfu/cm2, respectively, with a major impact of washing on TVC and washing and chilling onE. colidecrease (P< 0.001). BothSalmonellaspp. (6 strains) andListeriaspp. (12 strains, none ofL. monocytogenes) were found sporadically in all processing steps followed. However, a decreasing trend was observed inSalmonellacounts andListeriaspp. incidence during the processing. Thus, this study brings new valuable information on the dynamics of microflora during modern poultry processing.


Author(s):  
Vikas Kumar ◽  
D. Sukumar ◽  
M. Muruganantham

Squids perish rapidly like other fishes and require some treatment to maintain the quality for export. The microbial quality of frozen squid (Sepioteuthis lessoniana, Lesson 1830) treated with the commercial food grade chemicals imported from Spain was therefore studied. Dressed squids were treated with the chemicals Hidratech_4A (0.4%) and Whitech_3 (0.25%) dissolved in chilled freshwater (STCF) and chilled saltwater (STCS). Chilled squids not treated served as control (SNTC). Squids were quick frozen at -40°C in contact plate freezer and stored at-20±1°C. Samples were tested raw, after pre-processing, treatments and freezing and during storage at monthly intervals for 7 months. The microbial quality evaluation included Total Plate Count (TPC), Escherichia coli, Staphylococcus aureus, Vibrio cholerae and Salmonella. Study revealed a better quality of treated samples than control. Microbiological quality of STCS was better than STCF and SNTC. E. coli counts decreased after treatment. Salmonella and V. cholerae were absent.


1983 ◽  
Vol 46 (1) ◽  
pp. 58-60 ◽  
Author(s):  
J. B. STONE ◽  
A. N. MYHR ◽  
I. DAVIE

Effect on the microbiological quality of milk of using a special cleaning detergent (Diversey-Wyandotte, Inc.) for low-temperature (initial 43.8°C, end of wash 35.4°C) washing in a milking parlor pipeline system was compared to regular high-temperature (initial 73°C, end of wash 43.8°C) wash of the system. Microbiological quality of the milk was determined by standard plate count (SPC) and psychrotrophic bacterial count (PBC). Cleanliness of equipment was evaluated by measurement of calcium deposits and visual inspection. Statistical analysis of data over time (June 5 to September 16, 1980) indicated no difference in SPC and PBC of milk between low-and high-temperature washing and, although there was a significant negative slope of PBC with time, this was due to factors other than treatment. Calcium soil deposition and visible evaluation of the equipment were not different for the wash temperatures.


2020 ◽  
Vol 39 (01) ◽  
Author(s):  
Pankaj Kumar Gupta ◽  
Dinesh Chandra Rai ◽  
Vinod Kumar Paswan ◽  
Rajendra Panta ◽  
Ashok Kumar Yadav

The present study was conducted to evaluate the physico-chemical characteristics including Adulteration and Microbiological quality of cow raw milk collected from four different places of ASSI region in Varanasi. Samples were analysed to know the chemical composition, the results showed that the statistically average percentage of Moisture (87.46), Fat (3.87), Protein (3.15), Lactose (4.42), Ash (.712), pH (6.43) and acidity (0.147). The keeping quality of milk was evaluated by Methylene Blue Reduction Test (MBRT). This phenomenon testified that milk sample 1 is fair quality and remained sample were found good and excellent. The microbiological conclusion confirmed the presence (less or more) of microbial load in all the raw milk samples. The highest level of microbial quality in standard plate count (SPC) was 19.1×106 cfu/ml. in sample 1 and in logarithm value is 7.28 cfu/ml at the same time, the highest coliform bacteria 2.3×102 in logarithm value is 2.36 was found in the sample 2. The adulterations in raw milk were checked by the standard procedure. In cow’s raw milk the different mixed adulterant were found in two samples contaminated with detergent and pulverized soap. Besides different hazardous chemical adulterant, raw milk from sample 1 was detected with presence of hydrogen peroxide and sample 2 was contaminated formalin whereas urea was present in sample 2 and 4. Milk adulteration is a global concern and social problem. Increased demand, growth in competition in dairy industry and financial gain makes some producers to adulterate the milk thereby decreasing milk quality.


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