A Procedure for the Direct Microscopic Count of Bacteria in Non-fat Dry Milk

1989 ◽  
Vol 52 (6) ◽  
pp. 404-406
Author(s):  
C. N. HUHTANEN ◽  
C. O. JONES
Keyword(s):  
Milk Proteins ◽  
Bacterial Counts ◽  
Dry Milk ◽  
Microscopic Count ◽  
The Mean

Bacteria in non-fat dried milk (NDM) were enumerated by a method involving preliminary solubilization of the milk proteins in 0.015 N NaOH followed by centrifuging, washing in the NaOH, and microscopically examining stained smears. The method was used to enumerate bacteria in samples of NDM obtained from government surplus stocks or from local retail sources. Bacterial counts from surplus NDM ranged from 4.64 × 105 to 2.83 × 106/g (the mean and median were, respectively, 6.23 and 2.84 × 106/g). Counts from retail samples ranged from 4.48 × 105 to 2.42 × 107/g (mean and median were 5.57 and 2.85 × 106/g). The predominant bacteria in some samples were paired streptococci; other samples contained rod-shaped bacteria, some with identifiable spores. Comparison of this method with the Levowitz-Weber method indicated that it produced fewer artifacts, was applicable to NDM samples containing a wider range of bacteria, and did not require the use of the potentially carcinogenic tetrachloroethane.

Pyruvate as an Indicator of Quality in Grading Nonfat Dry Milk1

1982 ◽  
Vol 45 (6) ◽  
pp. 561-565 ◽  
Author(s):  
R. T. MARSHALL ◽  
Y. H. LEE ◽  
B. L. O'BRIEN ◽  
W. A. MOATS
Keyword(s):  
Geometric Mean ◽  
Regression Line ◽  
Skim Milk ◽  
Plate Count ◽  
Department Of Agriculture ◽  
Standard Plate Count ◽  
Geometric Average ◽  
Dry Milk ◽  
Standard Plate ◽  
Microscopic Count

Samples of skim milk and nonfat dry milk (NDM) made from it were collected, paired and tested for pyruvate concentration, [P], and Direct Microscopic count (DMC). The skim milk was tested for Standard Plate Count (SPC) and Psychrotrophic Plate Count (PPC). The geometric average DMC of skim milk was more than three times higher than that of the paired NDM samples. However, [P] of NDM was not significantly different from that of the skim milk. Although [P] of skim milk was poorly correlated with SPC and PPC, r = .31 and .26, respectively, it was relatively well correlated with DMC, r = .64. Data were widely dispersed around the regression line when [P] was ≤ 4.0 mg/L. However, [P] increased rapidly when DMCs were > 106/ml. A limit of 10 mg/L of [P] in NDM reconstituted 1:9 was chosen to represent the current U.S. Department of Agriculture Standard for DMC in NDM. This limit failed to classify about 10% of the samples correctly, assuming that each geometric mean DMC was correct. However, the probability that samples meeting the DMC standard would be rejected by the pyruvate test was quite low and the probability was moderate that samples which would be acceptable by the pyruvate test would be rejected by the DMC. For the latter, 28% of the samples having DMCs of ≥ 107/ml contained < 10 mg/L of pyruvate. No sample having ≥ 10 mg/L of pyruvate had a DMC of ≤ 107/ml. Pyruvate concentration in NDM did not change during storage at 5 or 32°C for 90 days.

scholarly journals Quantitation of Bacteria in Blood of Typhoid Fever Patients and Relationship between Counts and Clinical Features, Transmissibility, and Antibiotic Resistance

1998 ◽  
Vol 36 (6) ◽  
pp. 1683-1687 ◽  
Author(s):  
John Wain ◽  
To Song Diep ◽  
Vo Anh Ho ◽  
Amanda M. Walsh ◽  
Nguyen Thi Tuyet Hoa ◽  
...  
Keyword(s):  
Antibiotic Resistance ◽  
Salmonella Typhi ◽  
Multidrug Resistant ◽  
Buffy Coat ◽  
Broth Culture ◽  
Bacterial Counts ◽  
Duration Of Illness ◽  
The Mean ◽  
Independent Association ◽  
Number Of Bacteria

Salmonella typhi was isolated from 369 andSalmonella paratyphi A was isolated from 6 of 515 Vietnamese patients with suspected enteric fever. Compared with conventional broth culture of blood, direct plating of the buffy coat had a diagnostic sensitivity of 99.5% (95% confidence interval [CI], 97.1 to 100%). Blood bacterial counts were estimated by the pour plate method. The median S. typhi count in blood was 1 CFU/ml (range, <0.3 to 387 CFU/ml), of which a mean of 63% (95% CI, 58 to 67%) were intracellular. The mean number of bacteria per infected leukocyte was 1.3 (interquartile range [IQR], 0.7 to 2.4) CFU/cell (n = 81). Children (<15 years old;n = 115) had higher median blood bacterial counts than adults (n = 262): 1.5 (range, <0.3 to 387) versus 0.6 (range, <0.3 to 17.7) CFU/ml (P = 0.008), and patients who excreted S. typhi in feces had higher bacteremias than those who did not: a median of 3 (range, <0.3 to 32) versus 1 (range, <0.3 to 68) CFU/ml (P = 0.02). Blood bacterial counts declined with increasing duration of illness (P = 0.002) and were higher in infections caused by multidrug-resistant S. typhi (1.3 [range, <0.3 to 387] CFU/ml; n = 313) than in infections caused by antibiotic-sensitive S. typhi (0.5 [range, <0.3 to 32] CFU/ml; n = 62) (P = 0.006). In a multivariate analysis this proved to be an independent association, suggesting a relationship between antibiotic resistance and virulence in S. typhi.

A COMPARISON OF SIX METHODS OF PREPARING AND USING THE METHYLENE BLUE STAIN FOR BACTERIAL COUNTS BY THE DIRECT MICROSCOPIC METHOD*

1954 ◽  
Vol 17 (6) ◽  
pp. 179-184 ◽  
Author(s):  
Nathan Mantel ◽  
A. H. Robertson
Keyword(s):  
Methylene Blue ◽  
Federal State ◽  
Cooperative Study ◽  
Microscopic Method ◽  
Bacterial Counts ◽  
Blue Stain ◽  
Microscopic Count

A cooperative study, involving 12 federal, state, local, and private laboratories throughout the country, was conducted to evaluate six methods of preparing and using the methylene blue stain for the direct microscopic count of bacteria in milk. Three of the six methods were found superior, yielding significantly higher bacteria counts, at the same time providing greater ease in counting. These three methods are: Levine and Black's acid-and-water-free stain; North's aniline oil stain; and Anderson's polychrome stain.

EFFECT OF PASTEURIZATION ON THE DIRECT MICROSCOPIC COUNT OF EGGS

1971 ◽  
Vol 34 (4) ◽  
pp. 209-211 ◽  
Author(s):  
H. E. Hall ◽  
D. F. Brown ◽  
R. B. Read
Keyword(s):  
Methylene Blue ◽  
Bacterial Count ◽  
Bacterial Cells ◽  
Bacterial Counts ◽  
The North ◽  
Counting Chamber ◽  
Blue Stain ◽  
Microscopic Count ◽  
Whole Egg

When pasteurized whole eggs from breakers were examined by the Direct Microscopic Count (DMC) procedure, the bacterial count frequently appeared to be too low to correlate with the observed state of decomposition. The DMC of whole egg was found to decrease during pasteurization. To determine why, DMC's were done using the North Aniline Oil - Methylene Blue Stain and the Levowitz-Weber modification of the Newman-Lampert stain. Total bacterial counts also were made using the Petroff-Hausser counting chamber. Results indicated that the reduction in count resulted from lysis of some of the bacterial cells in egg rather than to loss of stainability. Crystalline lysozyme at the concentration found in egg and whole egg preparations produced similar reductions in the DMC of bacteria isolated from egg.

scholarly journals Distinction Between Dry and Raw Milk Using Monoclonal Antibodies Prepared Against Dry Milk Proteins

2004 ◽  
Vol 87 (8) ◽  
pp. 2720-2729 ◽  
Author(s):  
W.L. Chen ◽  
M.T. Huang ◽  
H.C. Liu ◽  
C.W. Li ◽  
S.J.T. Mao
Keyword(s):  
Monoclonal Antibodies ◽  
Milk Proteins ◽  
Raw Milk ◽  
Dry Milk

scholarly journals Cleaning of hospital floors with oiled mops

1963 ◽  
Vol 61 (4) ◽  
pp. 393-399 ◽  
Author(s):  
J. R. Babb ◽  
H. A. Lilly ◽  
E. J. L. Lowbury
Keyword(s):  
Nursing Staff ◽  
Hospital Ward ◽  
Airborne Bacteria ◽  
Vacuum Cleaner ◽  
Tank Model ◽  
Bacterial Counts ◽  
Staph Aureus ◽  
Repeated Use ◽  
The Mean ◽  
Cleaning Methods

A comparison was made of three methods for the removal of dust from a hospital ward floor.The viable bacterial counts of impression plates from the floor showed a mean reduction of 51 % after cleaning with fresh oiled mops, 40 % after cleaning with a tank model vacuum cleaner and 5 % after sweeping with a broom.The mean proportions of airborne bacteria, compared with viable counts before cleaning, were 192 % during and 194 % after cleaning with a broom; 128 % during and 103 % after cleaning with an oiled mop, and 82 % during and 48 % after cleaning with a vacuum cleaner. On repeated use the oiled mop dispersed almost as much dust as a broom, but this settled rapidly from the air.The effects of these cleaning methods on counts of presumptive Staph. aureus on the floor and in the air were similar to those found in counts of total organisms.We wish to thank Mr M. D. Wilkins for valuable assistance, the Domestic Superintendent and staff and the nursing staff for their co-operation, and Messrs Leeming Brothers Limited for supplies of ‘Kex’ mops and equipment.

scholarly journals Bacterial load of the surface of some selected Automated Teller Machines (ATMs) in Kano Metropolis, Nigeria

2020 ◽  
Vol 12 (1) ◽  
pp. 76-79
Author(s):  
S.M. Rufa’I
Keyword(s):  
Public Space ◽  
Bacterial Load ◽  
Personal Hygiene ◽  
Plate Count ◽  
Bacterial Counts ◽  
Automated Teller Machines ◽  
Standard Plate Count ◽  
Automatic Teller Machine ◽  
Before And After ◽  
The Mean

An Automated Teller Machine (ATM), also known as Automated Banking Machine (ABM) or cash machine and several other names, is a computerized telecommunication device that provides access to financial transactions in a public space without the need for a cashier or other intermediaries. The Automatic Teller Machine (ATM) has been widely used due to its convenience but also serves as a source of bacterial contamination. The aim of this work was to determine the bacterial load of surfaces of selected ATMs in Kano metropolis. Swab samples were collected from four (4) selected areas and ten (10) different study sites. The samples were collected using swabbing technique and standard plate count was employed for the enumeration of bacterial counts. The mean bacterial counts ranged between the lowest count of 1.20 x 102cfu/cm2 and the highest count of 1.78 x 102cfu/cm2 and the mean count of individual machine ranged from 1.70 x 101 cfu/cm2 upto 6.00 x 101cfu/cm2. All the ATMs were found to be contaminated. It could thus be concluded that the ATMs studied present a very great risk factor for cross contamination. The general public should therefore be enlightened on the possible health hazards associated with such items like ATMs and thus advised for strict personal hygiene and regular washing of hands before and after contact with ATMs so as to reduce the possible transfer of bacterial diseases and/or infections. Keywords: Automated Teller Machines (ATMs), Bacteria, Contamination, Kano metropolis.

An examination of teat drying with disinfectant impregnated cloths on the bacteriological quality of milk and on the transfer of Streptococcus agalactiae before milking

1985 ◽  
Vol 52 (3) ◽  
pp. 355-359 ◽  
Author(s):  
Charles H. McKinnon ◽  
Trevor M. Higgs ◽  
A. John Bramley
Keyword(s):  
Streptococcus Agalactiae ◽  
Quaternary Ammonium Compound ◽  
Plain Water ◽  
Ammonium Compound ◽  
Bacterial Counts ◽  
The Mean ◽  
Individual Paper ◽  
Quality Of Milk ◽  
Paper Towels

SUMMARYTotal bacterial counts of the milk from individual cows were measured for three groups of ten winter housed cows at three milkings. The teats were either (i) left unwashed or (ii) washed with disinfected water (60 ppm available iodine) and dried with individual paper towels or (iii) washed with plain water and then dried with a single fabric cloth impregnated with a polymeric bisguanide and a quaternary ammonium compound. The mean total bacterial counts/ml for the groups were 5820, 2108 and 1116 respectively. Treatments (ii) and (iii) were also compared for their ability to prevent the inter-teat transfer of bacteria. Before teat washing and drying, one teat of each cow was deliberately contaminated with Streptococcus agalactiae. Significantly fewer teats (5/30) became contaminated with Str. agalactiae when treatment (iii) was used for teat washing and drying compared with treatment (ii) (20/30).

Effects of fat concentration on the homogenization of cream

1983 ◽  
Vol 50 (1) ◽  
pp. 91-96 ◽  
Author(s):  
Leslie W. Phipps
Keyword(s):  
Volume Fraction ◽  
Milk Proteins ◽  
Maximum Area ◽  
A Value ◽  
Surface Active Properties ◽  
Fat Globule ◽  
Surface Active ◽  
The Mean ◽  
Semi Empirical ◽  
Fat Volume

SummaryA study has been made of the interdependence of the volume fraction and the degree of dispersion of the fat in creams subjected to single-pass homogenization. The effects of fat volume fraction φ could be incorporated into a semi-empirical correlation of the homogenizing variables established previously. In general, as φ increased from a low value the mean fat globule diameter at first decreased, reached a minimum and subsequently increased. The total area of the fat interface/m.l. volume when the globule diameter was a minimum proved to be independent of the homogenizing pressure and had a value of approximately 1·1 m2; the interface of maximum area was greater than this and, in contrast, its magnitude was pressure-dependent.The overall results have been interpreted in relation to the variability of the disruptive energy within the homogenizing valve, competing effects of globule coalescence and hindered break-up, and the surface-active properties of the milk proteins.

Distribution and Evolution of Bacteria on Lamb Carcasses During Aerobic Storage

1991 ◽  
Vol 54 (12) ◽  
pp. 945-949 ◽  
Author(s):  
MIGUEL PRIETO ◽  
MARÍA L. GARCÍA ◽  
MARÍA R. GARCÍA ◽  
ANDRÉS OTERO ◽  
BENITO MORENO
Keyword(s):  
Sampling Methods ◽  
Sampling Site ◽  
Storage Life ◽  
Sampling Point ◽  
Bacterial Counts ◽  
Mean Values ◽  
Ph Values ◽  
The Mean

The change of bacterial counts during storage life of chilled (3±1°C) lamb carcasses was determined by sampling at 0, 5, 10, and 15 d postslaughter and at the spoilage time. Three sites (neck, brisket, and leg) of each carcass were sampled using three sampling methods (swabbing, scraping, and excision of the swabbed and scraped areas). After slaughter, mean count of mesophiles (30°C) was 4.96 log10 CFU/cm2. The initial mean count of psychrotrophs (7°C) expressed as a percentage of the mean count of mesophiles was 33.4%. The mean values of mesophiles and psychrotrophs associated with spoilage were 7.4 log10/cm2 and 7.95 log10/cm2, respectively. Carcasses always had pH values above 5.8 and kept unspoiled 23–29 d. Brisket and leg were the most contaminated areas. Percentages of bacteria recovered by scraping were higher than those obtained by swabbing (ca. 20%). Bacterial counts were significantly affected by day of storage (p&lt;0.001), sampling point (p&lt;0.001), and temperature of incubation (p&lt;0.05). Interaction between sampling day and sampling site was also observed.

Sign in / Sign up

Export Citation Format

Share Document