What Is the Color of Milk and Dairy Products and How Is It Measured?

Abstract

Exactly six-hundred (600) scientific articles that report milk and milk products’ color results in scientific journals in the last couple of decades were reviewed. Thereof, the greatest part of the articles derived from Europe (36.3%) and Asia (29.5%). The greatest share of researchers used Minolta colorimeters (58.8%), while 26.3% of them used Hunter devices. Most reports were on cheese (31.0%) followed by fermented products (21.2%). Moreover, the highest number of papers reported color data of milk and milk products made from cow’s milk (44.81%). As expected, goat’s cheese was the brightest (L* = 87.1), while cow’s cheese was the yellowest (b* = 17.4). Most importantly, it appeared that color research results reported were often impossible to replicate or to interpret properly because of incomplete description of the methodology. In some of the manuscripts reviewed, illuminant source (61.0%), aperture size (93.8%), observer angle, and number of readings (over 70% of all cases) were not reported. It is therefore critical to set rules regarding the description of the methodology for (milk) color research articles in order to ensure replicability and/or comparison of studies.

Physicochemical, Microbiological and Technological Properties of Red Deer (Cervus elaphus) Milk during Lactation

“…These trends are closer to those found in sheep milk with different fat contents [ 60 ]. The mean value for yellowness (b* = 8.38) agrees with those found in other studies for deer milk [ 24 , 42 ]. The comparative observation of red deer milk yellowness with other species showed that this milk is yellower than sheep, goat, cow, camel or mare milk [ 24 , 42 , 60 ] ( Table 2 ).…”

“…Regarding color, the mean value for the L* coordinate was 89.94 ( Table 4 ), similar to values reported by others for deer milk [ 24 , 42 ] and slightly higher than the brightness values found in sheep and goat milk [ 24 , 60 ] ( Table 2 ). Brightness increased ( p < 0.002) with lactation, concurring with the increase in fat and protein contents ( Table 1 ).…”

“…In milk from other species such as sheep, a negative correlation for yellowness and fat content was observed [ 60 ], but although a marked increase in fat was observed at the end of lactation, yellowness tended to be stable ( p > 0.05) during lactation in red deer milk ( Table 4 ). These differences might be due to a different assimilation of carotenes and other natural pigments [ 42 ].…”

Development of Controlled-Release Carbamide Peroxide Loaded Nanoemulgel for Tooth Bleaching: In Vitro and Ex Vivo Studies

“…The ∆E values showed the degree of color difference for optical sensations. For ∆E less than 1, the color differences could not be noticeable to the human eye, ∆E in range of 1–3, the minor color differences could be noticeable to the human eye, and ∆E more than 3, the color differences could be noticeable to the human eye [ 40 ]. The ∆E values of both CP-NG was higher than 2 therefore the difference in color compared to hydrogel could be observable.…”

“…This whole assembly was kept on a magnetic stirrer and the medium solution was stirred continuously at 100 rpm. The temperature was maintained at 37 • C. The sample was withdrawn at 5,10,15,20,30,40,50,60,120,180,240,300,360,420, and 480 min and replaced with an equal amount of fresh dissolution medium. The withdrawal samples were subjected to HPLC analysis for the determination of the released CP.…”