A Collaborative Study to Determine the Feasibility of Using 0.40-, 0.20-, 0.14-, and 0.10-Inch-Diameter Discs to Measure Sediment in Fluid Milk

1977 ◽  
Vol 40 (1) ◽  
pp. 41-42
Author(s):  
EARL O. WRIGHT ◽  
WARREN S. CLARK ◽  
RICHARD W. WEBBER ◽  
WILLIAM L. ARLEDGE ◽  
MICHAEL H. ROMAN ◽  
...  
Keyword(s):  
Collaborative Study ◽  
Raw Milk ◽  
Laboratory Personnel ◽  
Milk Samples ◽  
Bulk Milk ◽  
Sediment Content ◽  
Trained Personnel ◽  
Fluid Milk

This collaborative study was done to determine whether laboratory personnel could successfully grade raw milk for sediment content using 0.40-, 0.20-, 0.14-, and 0.10-inch-diameter sediment discs. The 0.40-inch disc presently is accepted for grading sediment in mixed bulk milk samples. Technicians in 17 separate laboratories made 1,360 determinations (80 per laboratory) or 20 determinations for each size of sediment disc. Each laboratory graded the same set of samples. Samples were graded using photoprint standards that were prepared for this study. The laboratories were evaluated on the ability of laboratory technicians to grade the various sizes of sediment discs. Technicians in 13 of the 17 laboratories graded samples showing no significant differences in their ability to grade the various sized sediment discs. Four laboratories were not consistent in their ability to grade discs and showed significant differences in agreements with the previously determined sediment level as the diameter of the disc was reduced. Based on these results, most laboratories evaluated were capable of grading sediment discs with diameters of 0.40-, 0.20-, and 0.14-inch with consistency. With properly trained personnel in the laboratories, the study indicates the 0.10-inch diameter disc also can be used effectively for grading sediment in milk.

PRELIMINARY STUDY TO DETERMINE THE FEASIBILITY OF USING A 0.20-INCH DIAMETER DISK TO MEASURE SEDIMENT IN FLUID MILK

1974 ◽  
Vol 37 (8) ◽  
pp. 409-410
Author(s):  
Earl O. Wright ◽  
Donald K. Hotchkiss ◽  
Warren S. Clark
Keyword(s):  
Collaborative Study ◽  
Raw Milk ◽  
Laboratory Personnel ◽  
Milk Samples ◽  
Bulk Milk ◽  
Sediment Content ◽  
Preliminary Study ◽  
Fluid Milk

A preliminary collaborative study was done to determine whether laboratory personnel could grade raw milk for sediment content using 0.20-inch diameter as well as 0.40-inch diameter sediment disks. The 0.40-inch disk presently is used for grading sediment in mixed bulk milk samples. Technicians in 10 separate laboratories made 800 determinations (80 per laboratory) of known sediment amounts on 20-inch and 0.40-inch diameter standard sediment disks; 225 (63.7%) of 400 determinations made on the 0.20-inch diameter disk were graded accurately, whereas 187 (46.8%) of the 400 determinations made on the 0.40-inch diameter sediment disks were graded correctly. Based on these results, it is recommended that photoprint standards be developed for 0.20-inch diameter sediment disks and that a further collaborative study be undertaken.

scholarly journals Determination of Fat, Protein, and Lactose in Raw Milk by Fourier Transform Infrared Spectroscopy and by Analysis with a Conventional Filter-Based Milk Analyzer

1996 ◽  
Vol 79 (3) ◽  
pp. 711-717 ◽  
Author(s):  
Dominique Lefier ◽  
Remy Grappin ◽  
Sylvie Pochet
Keyword(s):  
Fourier Transform ◽  
Fourier Transform Infrared ◽  
Raw Milk ◽  
Milk Composition ◽  
Milk Samples ◽  
Bulk Milk ◽  
Different Seasons ◽  
Standard Deviations ◽  
True Protein ◽  
Single Calibration

Abstract The accuracy of fat, crude protein (CP), true protein (TP), and lactose determinations of raw milk by Fourier transform infrared (FTIR) spectroscopy and by analysis with a conventional filter-based milk analyzer was assessed in 6 trials performed over a 10-month period. At each trial, 30 bulk milk samples collected from 15 European countries and 11 reconstituted milks made from raw milk components were analyzed. When calibrations were performed with reconstituted milks at each trial, accuracy standard deviations for fat, CP, TP, and lactose were, respectively, 0.050,0.048,0.035, and 0.076 g/100 g for the filter instrument and 0.047, 0.046,0.042, and 0.065 g/100 g for the FTIR instrument. When a single calibration was made instead of calibrations at each trial, accuracy standard deviations increased for the filter instrument to 0.130, 0.119,0.121, and 0.083 for fat, CP, TP, and lactose, respectively, and for the FTIR instrument to 0.082, 0.053,0.044, and 0.084 g/100 g. Because the FTIR instrument provides more spectral information related to milk composition than does the filter instrument, single-calibration FTIR analysis of milk samples collected in different seasons is more accurate. Using reconstituted milks, prepared such that there is no correlation between fat, CP, and lactose, provides a more robust calibration than using genuine bulk milk, especially when milks with unusual composition are analyzed.

Collaborative Study of an Automated Optical Somatic Cell Counting Method for Raw Milk

1973 ◽  
Vol 56 (4) ◽  
pp. 950-956
Author(s):  
Wesley N Kelley
Keyword(s):  
Standard Deviation ◽  
Somatic Cell ◽  
Collaborative Study ◽  
Sampling Rate ◽  
Raw Milk ◽  
Cell Counting ◽  
Counting Method ◽  
Milk Samples ◽  
Comparison Of Results ◽  
Statistical Results

Abstract A collaborative study was conducted to compare tbe automated optical somatic cell counting method (OSCC) with the direct microscopic somatic cell counting method (DMSCC) for raw milk. Samples were prefixed with formaldehyde and introduced into an Auto-Analyzer system. Dilution, clarification, and cell counting were performed automatically. Eight collaborators participated in the study, analyzing 48 samples in duplicate, using 2 different sampling rates. The results were compared with DMSCC counts reported by 3 different analysts. Statistical results show that the standard deviation for the DMSCC method was 0.1086 and for the OSCC method, at a sampling rate of 30/hr, 0.0911. From comparison of results it appears that the OSCC method is as accurate as, and more precise than, the DMSCC method. The faster sampling rate of the OSCC method (60/hr) has some effect on precision but little effect on accuracy. The method has been adopted as official first action.

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.

scholarly journals The effect of cattle breed, season and type of diet on nitrogen fractions and amino acid profile of raw milk

2013 ◽  
Vol 56 (1) ◽  
pp. 709-718 ◽  
Author(s):  
L. Křížová ◽  
O. Hanuš ◽  
P. Roubal ◽  
J. Kučera ◽  
S. Hadrová
Keyword(s):  
Amino Acid ◽  
Milk Yield ◽  
Cattle Breed ◽  
Raw Milk ◽  
Amino Acid Profile ◽  
The Other ◽  
Nitrogen Fractions ◽  
Milk Samples ◽  
Bulk Milk

Abstract. The aim of the study was to describe the differences in nitrogen fractions and deepen the knowledge in the amino acid profile of raw milk affected by the breed of cattle, season and type of feeding. The study was conducted from June 2005 to February 2007 on 64 bulk milk samples collected from eight herds consisting of Czech Fleckvieh (four herds) and Holstein (four herds) breed. One half of the herds of each breed was grazed while the other half was not. Samples were collected twice in winter and twice in summer. The effect of the breed resulted in differences in milk yield that was lower in Czech Fleckvieh (5 385.50 kg) than in Holstein (7 015.15 kg, P<0.05). The content of nitrogen fractions was higher in Czech Fleckvieh than in Holstein (P<0.05). No effect of the breed on the amino acid profile of milk was observed except on the concentration of Glu (P<0.05). The effect of the season was demonstrated in the decrease of the concentrations of nitrogen fractions and Met during summer in comparison to winter (P<0.05). The effect of the type of feeding resulted in lower milk yield (5 197.50 and 7 203.75 kg) and lower concentrations of nitrogen fractions in grazed herds compared to non-grazed herds (P<0.05), respectively. Furthermore, the amino acid profile of milk differed significantly between grazed and non-grazed herds (P<0.05).

scholarly journals Adulteration of raw milk in the rural areas of Barisal district of Bangladesh

2013 ◽  
Vol 41 (2) ◽  
pp. 112-115 ◽  
Author(s):  
T Chanda ◽  
GK Debnath ◽  
ME Hossain ◽  
MA Islam ◽  
MK Begum
Keyword(s):  
Sodium Bicarbonate ◽  
Rural Areas ◽  
Positive Relationship ◽  
Raw Milk ◽  
Cane Sugar ◽  
Powdered Milk ◽  
Milk Samples ◽  
Entry Points ◽  
Fluid Milk

The study was undertakento detect the type of adulterants and preservatives added to the incoming fluid milk from rural areas to the Barisal city of Bangladesh. Total fifty milk samples were collected from five different entry points of Karapure, Dabdopia, Shaestabad, Goriarpar and Khanpura of Barisal district where ten samples were taken from each entry point. The results indicated that, 100% of the milk samples were adulterated with water irrespective of collection points and months. Cane sugar, powdered milk and starch were detected as 26.0, 14.0 and 12.0% in the milk samples, respectively. Two types of preservatives namely formalin and sodium bicarbonate were detected in the fluid milk from the study areas. Out of all samples, 10.0% was adulterated with formalin and 20.0% with sodium bicarbonate. However, none of the samples contained either hydrogen peroxide or borax. There was a positive relationship between day temperature and intensity of adding preservatives to the fluid milk. As the day temperature increased, the number of preservative positive samples also increased in a linear fashion and vice versa. It could therefore be inferred that, the consumers need to be more cautious regarding the quality of raw milk specially in summer season.DOI: http://dx.doi.org/10.3329/bjas.v41i2.14126Bang. J. Anim. Sci. 2012. 41 (2): 112-115

A Vapor Pressure Osmometer for Determination of Added Water in Milk

1975 ◽  
Vol 38 (4) ◽  
pp. 204-207 ◽  
Author(s):  
K. PENSIRIPUN ◽  
E. C. CAMPBELL ◽  
G. H. RICHARDSON
Keyword(s):  
Vapor Pressure ◽  
Collaborative Study ◽  
Raw Milk ◽  
Cow Milk ◽  
Filter Paper Disc ◽  
Milk Samples ◽  
Added Water ◽  
Sample Chamber ◽  
Paper Disc

A vapor pressure osmometer requiring a 5- to 7-microliter sample to saturate a 0.64 cm filter paper disc fixed a digital readout of milliosmolality in 110 sec. A coefficient of variability of 0.70 was obtained on a raw milk sample tested 25 times when an acetone impregnated tissue was used to clean the sample chamber between tests. Two hundred individual cow milk samples from 20 herds averaged 280.0 ± 3.0 milliosmols. Milk samples containing up to 25% added water were evaluated on both the vapor pressure osmometer and a thermistor cryoscope with a resultant correlation coefficient of 0.991. A collaborative study involving eight hospital and industry laboratories was conducted. When the results of two laboratories were discarded, due to instrument maintenance problems, there were no significant differences among the laboratories in their abilities to quantitate added water in milk.

Stability of Tetracycline Antibiotics in Raw Milk under Laboratory Storage Conditions

1999 ◽  
Vol 62 (5) ◽  
pp. 547-548 ◽  
Author(s):  
LYNDA V. PODHORNIAK ◽  
SHANITA LEAKE ◽  
FRANK J. SCHENCK
Keyword(s):  
Metal Chelate ◽  
Raw Milk ◽  
Storage Conditions ◽  
Screening Tests ◽  
Rapid Screening ◽  
Tetracycline Antibiotics ◽  
Milk Samples ◽  
Bulk Milk ◽  
Tetracycline Residues ◽  
Metal Chelate Affinity Chromatography

Raw milk samples collected from bulk milk tankers may be screened for the presence of tetracycline antibiotics using rapid screening tests. If tetracycline residues are detected, the milk may be shipped to a laboratory for high-pressure liquid chromatography (HPLC) analysis. Because the milk may be shipped on ice blocks, it is important to know whether tetracycline residues are stable at that temperature and for how long. Control raw milk samples fortified with 50 ppb each chlortetracycline, demeclocycline, methacycline hydrochloride, minocycline, oxytetracycline, and tetracycline were incubated at 4°C or 25°C, then analyzed using a metal chelate affinity chromatography extraction and HPLC. No loss of tetracycline was observed after 48 h of storage at 4°C or 24 h at 25°C. Losses ranging from 4 to 13% and 0 to 18% were noted after 72 h at 4°C and 48 h at 25°C, respectively.

Collaborative Study of the Babcock and Foss Milko-Tester Methods for Measuring Fat in Raw Milk

1969 ◽  
Vol 52 (1) ◽  
pp. 131-138
Author(s):  
W F Shipe
Keyword(s):  
Standard Deviation ◽  
Collaborative Study ◽  
Rapid Test ◽  
Reference Method ◽  
Raw Milk ◽  
Fat Content ◽  
Casein Micelle ◽  
Fat Globules ◽  
Standard Deviations ◽  
Fluid Milk

Abstract A rapid test for fat content in fluid milk, based on the measurement of light scattered by fat globules, was studied collaboratively. The Milko-tester instrument, developed by Danish scientists, was used. The milk is homogenized to produce uniformsized fat globules and then diluted with a Versene solution which eliminates the turbidity caused by the casein micelle. The amount of dilutant is adjusted so that the values obtained agree with the reference method being used for calibration. In two collaborative trials involving 6 laboratories and 9 samples, and 5 laboratories and 12 samples, respectively, the standard deviations were ±0.069 and ±0.074 for the Milko-tester and Babcock methods, respectively. The corresponding averages for the 21 samples were 4.70 and 4.69%. The standard deviation of difference between Milkotester and Babcock average values for the 21 samples was ±0.045%.

scholarly journals Hypoglycin A in Cow’s Milk—A Pilot Study

Toxins ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 381
Author(s):  
Mandy Bochnia ◽  
Jörg Ziegler ◽  
Maren Glatter ◽  
Annette Zeyner
Keyword(s):  
Safety Assessment ◽  
Raw Milk ◽  
Cow’S Milk ◽  
Cow's Milk ◽  
Milk Samples ◽  
Filling Station ◽  
Bulk Milk ◽  
Sycamore Maple ◽  
Carry Over ◽  
The Individual

Hypoglycin A (HGA) originating from soapberry fruits (litchi, and ackee) seeds or seedlings from the sycamore maple (SM) tree (related to Sapindaceae) may cause Jamaican vomiting sickness in humans and atypical myopathy in horses and ruminants. A possible transfer into dairy cow’s milk cannot be ruled out since the literature has revealed HGA in the milk of mares and in the offal of captured deer following HGA intoxication. From a study, carried out for another purpose, bulk raw milk samples from four randomly selected dairy farms were available. The cows were pastured in the daytime. A sycamore maple tree was found on the pasture of farm No. 1 only. Bulk milk from the individual tank or milk filling station was sampled in parallels and analyzed for HGA by LC-ESI-MS/MS. Measurable concentrations of HGA occurred only in milk from farm No. 1 and amounted to 120 and 489 nmol/L. Despite low and very variable HGA concentrations, the results indicate that the ingested toxin, once eaten, is transferred into the milk. However, it is unknown how much HGA the individual cow ingested during grazing and what amount was transferred into the bulk milk samples. As a prerequisite for a possible future safety assessment, carry-over studies are needed. Furthermore, the toxins’ stability during milk processing should also be investigated as well.

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