Selected abiotic factors that influence raw cow milk freezing point depression

Freezing point depression (FPD) is an important property of milk that is influenced primarily by milk components connected to osmotic pressure. Under certain conditions it is possible to detect the addition of water to milk. It is necessary to have the right FPD limit in legislation for milk quality control. The aim of this study was to improve the estimation procedure of this limit. Apart from factors related to dairy cow nutrition, cattle breed and milk yield, it is important to take into account CO2 (6%), water steam evaporation and pasteurization under technological conditions. Bulk milk samples (1, 30, 6, 6, 10, 1 according to experiment) from Holstein and Czech Fleckvieh breed (1:1) were used in the experiments and technologically treated. The effects of water addition (water saturated and unsaturated by CO2), carbon dioxide evaporation and pasteurization (80 °C for 22 min) were quantified. Pasteurization aggravation of FPD was -0.00394 ± 0.00171 ºC (P < 0.001). Aggravation due to carbon dioxide evaporation could be -0.00383 ± 0.00095 ºC (P < 0.001) depending on practice. Increase in FPD is recorded after milking during technological procedures of milk storage, mixing, pumping, transport shaking and warming. During FPD shift, the acuteness of FPD data sets increases. This fact should be considered in the process of deriving standard raw cow milk FPD limits. Similar experimental analysis of milk FPD technological shifts has not been performed in this way until now.

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The effects of sample fat value manipulation on raw cow milk composition and indicators

Acta Universitatis Agriculturae et Silviculturae Mendelianae Brunensis ◽

10.11118/actaun201159010101 ◽

2011 ◽

Vol 59 (1) ◽

pp. 101-112 ◽

Cited By ~ 3

Author(s):

Oto Hanuš ◽

Marcela Vyletělová ◽

Martin Tomáška ◽

Eva Samková ◽

Václava Genčurová ◽

...

Keyword(s):

Somatic Cell Count ◽

Crude Protein ◽

Freezing Point ◽

Milk Composition ◽

Cow Milk ◽

Freezing Point Depression ◽

Sampling Errors ◽

Milk Samples ◽

Actual Acidity ◽

The Impact

Values of milk indicators (MIs) can be influenced by sampling errors and milk manipulation. This paper estimated the freezing point depression (FPD) and other MIs drifts which can cause fat movement. That is important for: – preparation of reference milk samples (MSs) for proficiency testing and instrument calibrations; – estimation of the impact of milk treatment as centrifugation in dairy plants on FPD. Five MSs (A = original milk; milk with modified fat (F) content; B = less F, C = low F, D = more F, E = high F) were created (gravitation F separation at 4 °C for 12 hours) with the same milk matrix 12× per year. F averages increased by 4.80% (122.1%) from 1.68 to 6.48% due to manipulation. It increased variability of MIs especially for SNF (solids non fat), L (lactose) and CP (crude protein). SCC (somatic cell count) averages increased by 803 (196.8%) from 9 to 812 thousand.ml−1. Correlation (r) F × SCC was 0.85 (P < 0.001). SNF, L and CP averages decreased by 0.47% (5.3%), 0.31% (6.3%) and 0.17% (5.0%). Correlations were −0.78, −0.75 and −0.64 (P < 0.001). Urea decreased along with F increase by 1.05 mg.100ml−1 (2.9%) but with r −0.13 (P > 0.05). Acetone increased by 1.37 mg.l−1 (47.6%) with r 0.21 (P > 0.05). Electrical conductivity decreased by 0.23 mS.cm−1 (6.0%) with r −0.15 (P > 0.05). Alcohol stability was reduced by 0.14 ml (23.3%) with r −0.15 (P > 0.05). FPD, titration and actual acidity were not influenced.

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Evaluation of Cow Factors and Milk Composition on Freezing Point Depression of Cow Milk

International Journal of Livestock Research ◽

10.5455/ijlr.20160512114121 ◽

2016 ◽

Vol 6 (5) ◽

pp. 61 ◽

Cited By ~ 1

Author(s):

PGND Senevirathne ◽

ULP Mangalika ◽

AMJB Adikari ◽

WAD Nayananjalie

Keyword(s):

Freezing Point ◽

Milk Composition ◽

Cow Milk ◽

Freezing Point Depression

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Researches on Physico-Chemical and Microbiological Characteristics of Sheep and Cow Milk from Cristian Farm, Romania

Acta Universitatis Cibiniensis Series E Food Technology ◽

10.2478/aucft-2014-0009 ◽

2014 ◽

Vol 18 (1) ◽

pp. 77-84

Author(s):

Ionuţ Radu Popa ◽

Mihaela Tiţa ◽

Letiţia Oprean ◽

Ramona Iancu ◽

Ecaterina Lengyel ◽

...

Keyword(s):

Freezing Point ◽

Point Of View ◽

Cow Milk ◽

Coliform Bacteria ◽

Research Centre ◽

Water Addition ◽

Physical Chemical ◽

Microbiological Characteristics ◽

Physico Chemical ◽

Number Of Bacteria

Abstract This study was conducted over a period of three month in the Cristian farm, Sibiu. For the physical, chemical and microbiological analyzes were taken a number of 15 samples per month. From physico-chemical point of view the content evolution of fat, not fat solid substance, density, protein, freezing point, temperature, lactose, conductivity, pH, water addition was followed. Samples were analyzed using the milk analyzer Ekomilk Total of the Research Centre in Biotechnology and Microbiology of the "Lucian Blaga" University. The microbiological contamination of milk was done by determining the total number of bacteria and coliform bacteria. From microbiological point of view it was observed that these conditions are largely met, but a more rigorous control on the cleanliness of utensils and of the staff is required.

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A Method for Determining Total Carbon Dioxide in Small Volumes of Liquid

Journal of Experimental Biology ◽

10.1242/jeb.52.2.395 ◽

1970 ◽

Vol 52 (2) ◽

pp. 395-400

Author(s):

COLIN LITTLE ◽

GARY RUSTON

Keyword(s):

Carbon Dioxide ◽

Standard Deviation ◽

Freezing Point ◽

Present Form ◽

Total Carbon ◽

Barium Hydroxide ◽

Freezing Point Depression ◽

Dissolved Carbon ◽

Hydroxide Solution ◽

Dissolved Carbon Dioxide

1. A microdiffusion method for estimating total dissolved carbon dioxide in volumes of approximately 1.5 µl. is described. The principle of the method is to displace the CO2 with acid, to absorb it in barium hydroxide solution and to measure the change in the freezing-point depression of this solution. 2. The range of measurement is 0-30 mM/l. HCO3 with a standard deviation of ± 0.3-0.4 mM/l. 3. In its present form the method cannot be used with smaller volumes without correcting for errors arising from the diffusion of water vapour between the sample and the barium hydroxide solution.

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Chosen biotic factors influencing raw cow milk freezing point

Acta Universitatis Agriculturae et Silviculturae Mendelianae Brunensis ◽

10.11118/actaun201159050065 ◽

2011 ◽

Vol 59 (5) ◽

pp. 65-82

Author(s):

Oto Hanuš ◽

Yunhai Zhang ◽

Marek Bjelka ◽

Josef Kučera ◽

Petr Roubal ◽

...

Keyword(s):

Freezing Point ◽

Physical Property ◽

Milk Composition ◽

Cow Milk ◽

Dairy Herds ◽

Water Addition ◽

Protein Ratio ◽

Physiological Factors ◽

Milk Urea ◽

Dairy Cow Nutrition

The milk freezing point depression (FPD) is important physical property. FPD is influenced by milk composition especially by components with osmotic pressure activity and by other physiological factors. There is possible to indicate a foreign (extraneous) water addition into milk by FPD. This is necessary to have a good estimated legislative FPD discrimination limit (FPD–L) for purpose of milk quality control. This paper was aimed at obtaining information to improve such estimation. Impacts factors as season variations, estimated state of dairy cow nutrition and some milk components and properties on milk FPD and their relations to FPD were quantified (n 11 540 – 72 607 bulk raw cow milk samples). The highest FPD was in Spring (−0.52097 ± 0.004877 °C), the lowest in Autumn (−0.52516 ± 0.005725 °C; P < 0.001). Correlation between FPD and lactose was 0.35 (P < 0.001). 12% and 5.4% of FPD variability is explainable by lactose and casein variability. Relationship between FPD and urea (U) was 0.26 (P < 0.001) in March. The worst FPD was in group with presupposed (according to milk urea and protein combination) nitrogen matter (NM) and energy (E) insufficiency (−0.51855 ± 0.007288 °C). The best FPD was in group with presupposed NM and E surplus in feeding ration (−0.52536 ± 0.004785 °C; P < 0.001). The FPD was worse in suspicion on E deficiency (on the basis of fat/crude protein ratio) as compared to presumption for balanced E nourishment of dairy herds (−0.52105 ± 0.006436 °C > −0.52244 ± 0.005367 °C; P < 0.001). Results can improve the estimation of objective FPD–L.

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