scholarly journals A Comparative Study on the Quality of Available Brand and Non Brand Fluid Milk Consumed by the People of Chittagong City of Bangladesh

2016 ◽  
pp. 16-20
Author(s):  
GK Debnath ◽  
AKMH Kober ◽  
T Chanda ◽  
GC Chanda ◽  
MS Bari
Keyword(s):  
Comparative Investigation ◽  
Plate Count ◽  
Standard Plate Count ◽  
Milk Samples ◽  
The People ◽  
Microbiological Parameters ◽  
Standard Plate ◽  
Quality Of Milk ◽  
Fluid Milk

The study was undertaken to have a comparative investigation on the quality of available brand and non-brand fluid milk consumed by the inhabitants of Chittagong City (CC). Milk samples were collected from the city vendors, departmental stores, households and dairy farms. A total of 100 samples were analyzed for nutritional (percentage of butter fat, solids-not-fat and protein), chemical (pasteurization test, added preservatives and adulteration status) and microbial (standard plate count and coliform count) parameters to evaluate the quality of the collected milk samples. The study reveals that the collected milk samples show significant (P?0.01) variation in nutritional, chemical and microbiological parameters among the sources. All brands milk samples were properly pasteurized. The quality of milk samples from local farms was good except coliform counts. All the samples possessed high coliform counts. The quality of farm produced milk and rural milk were deteriorated by middlemen due to adulteration with water. Water adulteration was detected in 68% and 54% of the milk samples in case of vendor supplied rural and vendor supplied farm milk respectively. Most alarming fact is more than 10% milk samples contained formalin in case of vendor supplied rural milk. It may be concluded that both the vendor supplied rural milk and vendor supplied farm milk were low quality due to water adulteration and added formalin preservatives respectively.International Journal of Natural Sciences (2014), 4(1) 16-20

THE QUALITY OF RAW MILK FROM SELECTED OHIO MARKETS.

1966 ◽  
Vol 29 (4) ◽  
pp. 118-121 ◽  
Author(s):  
S. P. Ohri ◽  
W. L. Slatter
Keyword(s):  
Raw Milk ◽  
Plate Count ◽  
High Count ◽  
Coliform Count ◽  
Standard Plate Count ◽  
Milk Samples ◽  
Bacteriological Method ◽  
Standard Plate ◽  
Bulk Tank

Summary An 8-month survey of the bacteriological quality of bulk tank produced fluid milk supplies for four major markets in Ohio, was made utilizing the Standard Plate Count (SPC), the preliminary incubation count (PI), the thermoduric (pasteurized milk) count, and the coliform count. In terms of maximum standards of 200,000 and 100,000 organisms/ml, the SPC would have eliminated 13% and 20% of the milk samples, respectively. A SPC of 50,000/ml, a PI count of 200,000/ml, a thermoduric count of 500/ml, and a coliform count of 100/ml would have eliminated 37%, 34%, 40%, and 40%, respectively, of the samples but not all of the samples eliminated by one test were eliminated by another test. All of the tests employed showed a seasonal trend especially in the high count categories but the trend was less noticeable in the results of the preliminary incubation count. A combination of two of the methods was superior to any single bacteriological method employed in detecting unsatisfactory milk. Of the tests used, the combination of the thermoduric count (500/ml) and the coliform count (100/ml) was the most effective in the detection of unsatisfactory milk samples.

scholarly journals Bacteriological quality of raw milk marketed in and around Guwahati city, Assam, India

2021 ◽  
Vol 14 (3) ◽  
pp. 656-660
Author(s):  
Smita Kakati ◽  
Archana Talukdar ◽  
Razibuddin Ahmed Hazarika ◽  
Masuk Raquib ◽  
Saurabh Kumar Laskar ◽  
...  
Keyword(s):  
Standard Procedure ◽  
Raw Milk ◽  
Poor Quality ◽  
Plate Count ◽  
Coliform Count ◽  
Standard Plate Count ◽  
Milk Samples ◽  
Guwahati City ◽  
Standard Plate

Background and Aim: Milk is a highly perishable commodity, which is subjected to various types of contamination right from the farm level to the consumers' table. This study aimed to assess the quality of raw milk sold in and around Guwahati city based on the microbial load. Materials and Methods: A total of 200 raw pooled milk samples collected from 25 different locations in and around Guwahati city were subjected to quality evaluation based on the methylene blue reduction test (MBRT), standard plate count, and coliform count as per the standard procedure. Results: Out of the 200 samples evaluated, more than 50% of them were graded as poor to very poor quality based on the MBRT results. None of the samples could be graded as excellent quality and only 14.5% were graded as good quality. The standard plate count and coliform count of all the raw milk samples were found to be significantly higher than the legal standard. A highly significant (p<0.01) difference was observed for standard plate count and coliform count among the different locations in and around Guwahati city. Conclusion: From the present study, it could be inferred that raw milk sold in most parts of Guwahati city do not confer to the legal microbiological standard and may pose a high risk of milk-borne illness among consumers of the city, which needs a systematic series of actions to be implemented properly.

KEEPING QUALITY OF MILK EXPOSED TO HIGH TEMPERATURE AS EXPERIENCED DURING TRANSPORT IN AUTOMOBILES1

1972 ◽  
Vol 35 (10) ◽  
pp. 588-590
Author(s):  
K. L. Smith ◽  
L. E. Mull ◽  
C. B. Lane ◽  
A. J. Baggott
Keyword(s):  
High Temperature ◽  
Storage Temperature ◽  
Storage Period ◽  
Plate Count ◽  
Lag Phase ◽  
Standard Plate Count ◽  
Warm Weather ◽  
Standard Plate ◽  
Quality Of Milk

To simulate conditions encountered in automobiles during warm weather in Florida, half-gallon cartons of milk, after tempering at 39 F, were exposed to 120 F for 0, 30, 60 or 90 min, after which milks were 39, 64, 78, and 91 F, respectively. All samples were then held at 39 F throughout the remainder of the study. The standard plate count was significantly higher on samples exposed to 120 F for 60–90 min than on those exposed for the shorter time. A taste panel detected flavor differences among samples of milk receiving the different heat exposures. The shelf-life of fluid milk was determined by the number of bacteria present in the sample at the commencement of the storage period, the length of the lag phase of growth, the rate of bacterial growth at the storage temperature used, and finally the type of microorganism present. If milk is to be exposed to high temperature in an automobile for more than 30 min, it should be held in an insulated container until it can be placed in the home refrigerator.

Evaluation of a Rapid Impedimetric Method for Determining the Keeping Quality of Milk

1982 ◽  
Vol 45 (13) ◽  
pp. 1221-1226 ◽  
Author(s):  
S. B. MARTINS ◽  
S. HODAPP ◽  
S. W. DUFOUR ◽  
S. J. KRAEGER
Keyword(s):  
Shelf Life ◽  
Correlation Coefficients ◽  
Sample Volume ◽  
Plate Count ◽  
Impedance Method ◽  
Detection Time ◽  
Standard Plate Count ◽  
Milk Samples ◽  
Standard Plate ◽  
Quality Of Milk

Shelf-life of 151 pasteurized milk samples was recorded and correlation coefficients calculated using various microbiological factors: standard plate count (SPC), psychrotrophic plate count (PPC), coliform count (CC), and the impedance response detection time (DT) with incubation at both 21 and 32°C. These data were obtained for milk samples on the day of pasteurization as well as 4 and 8 d thereafter. Various treatments (media, dilution factors, temperature and sample volume) were compared. Of the SPC, PPC, CC and DT taken on the day of pasteurization, only the DT achieved a significant correlation with shelf-life. A correlation coefficient of 0.55 was obtained for one treatment applied to 61 samples and correlation coefficients of 0.28 to 0.32 were obtained for several other treatments applied to the entire 151 samples. Values as large as these could occur by chance in uncorrelated data with p&lt;0.0005. Thus, of the total 61 samples, 80% were correctly classified by the impedance detection time test. It is concluded that for prediction of shelf-life on the day of pasteurization, the impedance method is superior to the SPC and the PPC. In addition, the impedance method is more rapid, i.e., 14 h vs.2 d for the SPC and 10 d for the PPC.

Pyruvate in Producer and Commingled Manufacturing Grade Milk

1982 ◽  
Vol 45 (13) ◽  
pp. 1236-1241 ◽  
Author(s):  
R. T. MARSHALL ◽  
B. L. O'BRIEN ◽  
Y. H. LEE ◽  
W. A. MOATS
Keyword(s):  
False Negative ◽  
Skim Milk ◽  
Plate Count ◽  
Negative Type ◽  
Standard Plate Count ◽  
Milk Samples ◽  
Standard Plate ◽  
Microscopic Count ◽  
Highly Correlated

The automated test for pyruvate concentration, [P], was evaluated as a substitute for the direct microscopic count (DMC) in determining quality of manufacturing grade milk. Samples of manufacturing grade milk from producers and tank trucks as well as skim milk were collected at a large milk drying plant. Each sample was tested immediately for standard plate count (SPC), psychrotrophic plate count (PPC) and DMC. Portions of milk were heated to 85°C for 10 min to stabilize [P] before being returned to the laboratory for analysis of initial pyruvate concentration, [IP]. Unheated samples stored at 4°C were analyzed for [P] and DMC daily for up to 120 h. [IP] was a good indicator of PPC in milk from individual producers (r=0.81). However, [IP] was not highly correlated (r=0.26) with PPC in skim milk samples which were characteristically high in SPC and homogeneous in PPC. With skim milk, [IP] was more highly and significantly correlated with initial DMC (r=0.61) than with initial SPC (r=0.31) or initial PPC (r=0.26). [IP] was a good indicator of [P] in stored fluid samples until counts exceeded about 107/ml. Initial DMC and initial PPC were about equally correlated with [P] determined at 24-h intervals, and the initial DMC was a reasonably good indicator of DMC determined at 24-h intervals. Using 6.5 mg of pyruvate/L to represent bacterial counts of 3 × 106/ml by the three methods tested, the pyruvate test correctly classified 91% of 57 samples of producer milk based on PPC, 88% based on SPC and 82% based on DMC. Most of the error was of the false-negative type in which samples with high counts had less than 6.5 mg of pyruvate/L. This was probably because some bacteria catabolize pyruvate once their numbers exceed 107/ml.

Preliminary Incubation Count as an Index of Raw Milk Microbiological Quality During Storage

1984 ◽  
Vol 47 (3) ◽  
pp. 206-208 ◽  
Author(s):  
J. J. RYAN ◽  
R. H. GOUGH ◽  
C. H. WHITE
Keyword(s):  
Microbiological Quality ◽  
Storage Period ◽  
Raw Milk ◽  
Plate Count ◽  
Bacterial Counts ◽  
Sample Group ◽  
Psychrotrophic Bacteria ◽  
Standard Plate Count ◽  
Milk Samples ◽  
Standard Plate

During a 5-month period, 200 raw milk samples were collected from two Louisiana milk plants. Standard Plate Count (SPC), Psychrotrophic Bacteria Count (PBC), and Proteolytic Count (PC) of each sample were initially determined, then monitored daily during a 5-d storage period at 2.2°C. As hypothesized, all bacterial counts increased during the storage period. The magnitude of the increase in bacterial numbers during storage was further investigated by dividing the milk samples into bacteriologically acceptable and unacceptable groups based on SPC or Preliminary Incubation (PI) count. An SPC of 1.0 × 105/ml and PI counts of 1.0 × 105/ml, 1.5 × 105/ml, 2.3 × 105/ml, and 3.0 × 105/ml were used to repeatedly dichotomize the 200 raw milk samples into two groups. Median SPC, PBC, and PC for each acceptable and unacceptable group were then calculated. Dichotomization based on PI counts yielded acceptable sample groups having consistently lower bacterial counts during storage than did the acceptable sample group, which resulted from the dichotomization based on a SPC of 1.0 × 105/ml. The results of this study indicated that the PI count is of considerable value for raw milk quality control.

Collaborative Study of the Impedance Method for Examining Raw Milk Samples

1984 ◽  
Vol 47 (9) ◽  
pp. 707-712 ◽  
Author(s):  
R. FIRSTENBERG-EDEN
Keyword(s):  
Collaborative Study ◽  
Raw Milk ◽  
Plate Count ◽  
Impedance Method ◽  
Standard Plate Count ◽  
Milk Samples ◽  
Automated Method ◽  
Significant Difference ◽  
Standard Plate ◽  
Contamination Levels

The impedance method is a rapid automated method for determining bacteriological contamination levels. A collaborative study was done to establish the reproducibility of the impedance method in predicting counts of raw milk. Frozen and unfrozen raw milk samples, with counts in the range of 9 × 104 to 4 × 107 CFU/ml, were sent to six laboratories to be examined by the standard plate count method (SPC) and by the impedance method which produced Bactometer-predicted counts (BPC). The impedance results showed less variability than SPC among laboratories in all three trials. The variance between split samples was also smaller for the impedance method than for SPC. However, the variance between duplicate plates of the same sample was significantly smaller for SPC than for BPC. In one trial, the means of BPC and SPC were not significantly different, whereas in another trial there was a significant difference of ca. log10 0.27 between the means of the two methods. However, in this trial the extreme differences between laboratories counting the same sample were log10 0.42.

Impedance Measurements in Raw Milk as an Alternative to the Standard Plate Count1

1982 ◽  
Vol 45 (1) ◽  
pp. 4-7 ◽  
Author(s):  
S. GNAN ◽  
L. O. LUEDECKE
Keyword(s):  
Yeast Extract ◽  
Geometric Mean ◽  
Raw Milk ◽  
Plate Count ◽  
Impedance Method ◽  
Microbial Count ◽  
Specific Detection ◽  
Standard Plate Count ◽  
Milk Samples ◽  
Standard Plate

Electrical impedance, using the Bactometer 32, was evaluated as an alternative method to the Standard Plate Count (SPC) to determine the initial microbial count of raw milk samples. The raw milk samples were obtained from farm bulk tanks on commercial dairy farms. Analyses were started within 24–36 h after collection. The impedance method was used to evaluate the samples as raw milk, raw milk plus yeast extract, raw milk given preliminary incubation (18 h at 13 C) or raw milk given preliminary incubation plus yeast extract. The yeast extract (1% final concentration) was added after the milk was placed in the module wells. The geometric mean SPC of each of these four groups was 4.51, 4.37, 4.96 and 5.14, and the corresponding mean detection times with Bactometer 32 were 10.13, 8.80, 8.28 and 6.11 h, respectively. The correlation coefficient of detection time to SPC was −0.77, −0.88, −0.78 and −0.79, respectively, for the four sample groups. When specific detection cut-off times (approximately 7 h) were selected and a maximum SPC of 100,000 CFU/ml was selected, 85.2%, 97.2%, 81.0% and 83.6%ofthe samples in the above four groups were correctly classified.

scholarly journals Microbiological Profile of the Traditionally Collected Industrial Raw Milk from the Milk Pocket Zones of Bangladesh

1970 ◽  
Vol 25 (1) ◽  
pp. 17-20 ◽  
Author(s):  
Gouranga C Chanda ◽  
Gazi M Noor Uddin ◽  
Aparna Deb ◽  
Tahmina Bilkis ◽  
Sharmin Chowdhury ◽  
...  
Keyword(s):  
Bacterial Count ◽  
Raw Milk ◽  
Total Coliform ◽  
Plate Count ◽  
Coliform Count ◽  
Standard Plate Count ◽  
Milk Samples ◽  
Bacteriological Profile ◽  
Standard Plate ◽  
Viable Bacteria

The study was aimed to evaluate the bacteriological profile of the traditionally collected industrial raw milk from the milk pocket zones of Bangladesh. About 365 raw milk samples were collected from the milk tanker, who brought raw milk from the mother chilling centre where raw milk was chilled at 4°C following traditional method. All milk samples were subjected to perform standard plate count and total coliform count. The average standard plate count was found to be 4.37 x 106 cfu/ml and the highest occurrence of standard plate count was found to be 6.70 x 106 cfu/ml in October and the lowest (3.28 x 106 cfu/ml) in March. The highest occurrence of total viable bacteria was found to be 5.64 x 106 cfu/ml in autumn and the lowest was found to be 3.78 x 106 cfu/ml in summer. On the other hand, the average of the coliform bacterial count was found to be 3.88 x 105 cfu/ml with the highest (5.70 x 105 cfu/ml) occurrence in May and the lowest (1.90 x 105 cfu/ml) in January. Moreover, the highest occurrence of coliform count was found to be 4.84 x 105 cfu/ml in rainy season and the lowest was 2.75 x 105 cfu/ml found in winter.DOI: http://dx.doi.org/10.3329/bjm.v25i1.4849 Bangladesh J Microbiol, Volume 25, Number 1, June 2008, pp 17-20

COMPARISON OF PLATE LOOP AND AGAR PLATE METHODS FOR BACTERIOLOGICAL EXAMINATION OF MANUFACTURING GRADE RAW MILK1,2

1967 ◽  
Vol 30 (4) ◽  
pp. 112-115 ◽  
Author(s):  
Sita Ramayya Tatini ◽  
Roger Dabbah ◽  
J. C. Olson
Keyword(s):  
Agar Plate ◽  
Bacterial Count ◽  
Raw Milk ◽  
Substantial Improvement ◽  
Plate Count ◽  
Bacteriological Examination ◽  
Standard Plate Count ◽  
Milk Samples ◽  
Standard Plate ◽  
Bulk Tank

Summary Plate loop counts and standard plate counts on each of several manufacturing grade raw milk samples (handled in cans or in farm bulk tanks) have been compared. On the average, the plate loop count (PLC) was lower than the standard plate count (SPC) regardless of the type of handling of milk on the farm, can or bulk tank. Agreement between the SPC and PLC seemed to depend upon the bacterial-count levels present in milk. Statistical analyses indicated significant differences, at 1% level of probability, between the average bacterial count by SPC and PLC methods regardless of count level (≤100,000/ml or &gt;100,000/ml) in case of can milk samples. On the other hand, in case of farm bulk tank milk samples, no significant differences, at the 1% level of probability, between the average bacterial count by SPC and PLC methods were obtained, when the counts were equal to or less than 100,000 per ml; when the counts exceeded 100,000 per ml, significant differences were present. Since the bacterial counts of manufacturing grade raw milk samples are likely to exceed 100,000/ml, the data presented in this investigation indicate that, until the bacteriological quality of manufacturing grade milk supplies undergoes substantial improvement, the PLC method does not appear to be a suitable substitute for the SPC method for routine bacteriological examination of such milk supplies.

Sign in / Sign up

Export Citation Format

Share Document