Measurement of Milk Color and Composition: Effect of Dietary Intervention on Western Australian Holstein‐Friesian Cow's Milk Quality

Abstract

Milk fat whiteness is the key to the uniqueness of Western Australian milk. Following a controlled feeding regime, milk was collected fortnightly for 6 mo from 2 treatment groups: dryland and irrigation. The results showed that it was possible to produce high-quality milk with whiter fat by a controlled feeding regime and diet while maintaining the health of Holstein-Friesian cows. The reflectance method using infinite optical thickness showed milk fat color differences due to feed could be measured. After 8 wk of the study, milk fat from the dryland treatment was significantly whiter (P < 0.05) than the irrigation treatment with area under curve total reflectance of 902.8 and 838.3, respectively. The official Japanese industry method, Agriculture and Livestock Industries Corp. (ALIC) butter tone, showed that from the 2nd to the 5th collections the color of milk fat from cows fed silage and grain (dryland treatment) was significantly whiter (P < 0.01) with an average butter tone of 0.15 absorbance per gram compared to cows fed green pasture and grain (irrigation treatment) with a butter tone of 0.21 absorbance per gram. Protein and riboflavin levels also affect the whiteness of milk. The study followed the main feeding protocol of dryland dairies and suggests the majority of milk from Western Australia would receive a grade 1 classification, as dryland dairies dominate supply.

Buffalo (Bubalus bubilis) colostrum and milk fat globule membrane fractions are potent antioxidants

“…Buffalo milk is also one of the compositionally richest milks [2]. Compared to other animals fat constitutes the main fraction of buffalo milk, with almost twice the fat content of bovine milk (7.4-8.8% (w/w) vs 3.6-4.7% (w/w)) [3,4] and this fat is responsible for the high energetic and nutritive value of buffalo milk. Colostrum, the lacteal secretion vital for mammalian newborn is a complex physiological fluid loaded with free oligosaccharides, glycoproteins, gangliosides, phagocytes, antimicrobial and immune-enhancing components which are unique compared to normal milk [5,6].…”

Quantitative assessment of German Holstein dairy cattle colostrum and impact of thermal treatment on quality of colostrum viscosity and immunoglobulins

“…including dietary composition also considered as contributory factors (16)(17)(18). However, a correlation between color and viscosity was not previously reported.…”

Instrumental measurement of milk flavour and colour

“…Yellow index (YI) was used by Pagliarini et al (1990) to monitor the colour changes in heat-treated milk. In addition to the above-mentioned tristimulus systems, spectral reflectance measurements (400 to 700 nm) are also a suitable estimate of degree of Instrumental measurement of milk flavour and colour 197 whiteness in milk (Nelson, 1948;Quin Äones et al, 1997;Solah et al, 2007). Some recent applications of colorimetric and spectrophotometric systems for measurement of colour in milk products can be found in the published literature (Nielsen et al, 1997;Browning et al, 2001;Gervilla et al, 2001;Nozie Áre et al, 2006;Solah et al, 2007;Popov-Raljic  et al, 2008).…”

“…Fluid milk varies in colour from opaque white to yellowish-white or even to a blueish tinted white (Doan, 1924). The observed colour of milk is attributed to the light reflectance properties of the milk components such as fat globules, colloidal substances (e.g., proteins), -carotene and riboflavin (Solah et al, 2007). From a quality standpoint it has mainly been the discolouration of milk caused by Maillard (nonenzymatic) browning that has concerned the dairy industry.…”