Effect of organic farming on selected raw cow milk components and properties
2011
Ivana Cermanová | Oto Hanuš | Petr Roubal | Marcela Vyletělová | Václava Genčurová | Radoslava Jedelská | Jaroslav Kopecký | Alena Dolínková
Organic dairying is an alternative for friendly exploitation of environment. This paper was focused on impacts of organic dairying on milk composition and properties. The conventional (C) cow milk was compared to organic (O) milk. Holstein bulk milk samples (BMSs) from winter and summer season in 4 C and 4 O (n = 32 and 32 BMSs; 2 years) herds were investigated. 6 herds were grazed and 2 C herds were not grazed. Mean O cow milk yield (MY, 305 lactation days) was 7037.3 ± 421.5 and C MY 7015.8 ± 1068.1 kg. Higher values (P < 0.05) in O milk had: log acetone (0.7321 > 0.6048); titration acidity (8.34 > 7.82 ml 0.25 mol.l−1 NaOH); alcohol stability (0.6 > 0.44 ml); time for enzymatic coagulation (150.75 > 115.03 second); whey protein (0.54 > 0.49%); fat/crude protein (1.2 > 1.15); milk fermentation ability (FAM) by titration (31.45 > 22.18 ml 0.25 mol.l−1 NaOH). Lower values (P < 0.05) in O milk had: solids–not–fat (8.64 < 8.73%); urea content (19.91 < 29.03 mg.100ml−1); electrical conductivity (3.66 < 4.08 mS.cm−1); whey volume (32.03 < 34.53 ml); crude protein (3.16 < 3.25%); casein (2.47 < 2.58%); non–protein nitrogen compounds (0.15 < 0.18%); urea nitrogen in non-protein nitrogen ratio (40.81 < 49.0%); casein numbers for crude protein and true protein (78.12 < 79.58 and 81.99 < 84.11%); coli bacteria count in normal and logarithm form (330.56 < 1502.92 CFU.ml−1 and 1.484 < 2.5823); actual yoghurt acidity (4.71 < 4.8). O cows suffered probably from lower energy and nitrogen compounds intake due to feeding under mentioned conditions. O milk could be a little better environment for yoghurt cultivation.
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