Abstract
A comparative analysis of camel milk based on the conducted typology on the average values of the physicochemical composition was carried out. The typology is done by the method of automatic classification (hierarchical descending classification) using Ward’s distances. Three classes of camel milk are obtained according to the obtained histogram of hierarchy level indices, the composition of each is very different among other. Since the samples of milk contrast strongly depending on the season of the year, and the region of animal breeding, two stages have been proposed to describe the variability of the composition of milk, depending on the species of animals. First, a typology of milk profiles based on the method of the principle components analysis on orthogonal instrumental variants (ACPVI) was developed and the distribution of these profiles by "animal species" were described with the elimination of the influence of the "region" and the "season of the year" factors. Secondly, a discriminant function of milk composition parameters is established, which allows a better separation of the species of animals. According to the ACPVI classification, 4 classes of milk are obtained that differ well and are grouped as milks "rich" (class 1), "low in protein" (class 2), low iodine number (class 3) and milk acidified and with low content of vitamin C (class 4). The distribution of different species in the classification showed that milk in 1st class mainly consists of Bactrian samples (58,9%), and the 2-class is mostly composed of dromedary. Nevertheless, milk samples of the dromedary are presented in the 2nd, 3rd and 4th classes. Regarding the milk of hybrids and collectied milk, it was difficult to attribute them to a clearly expressed class. Further, the influence of the "season" factor on the composition of milk was studied. According to the results of the ACPVI analysis, 5 classes were obtained, where class 1 (spring samples mainly) is characterized as a milk, which is "poor" in all the parameters used, excepting the total nitrogen content; class 2 (mainly summer samples) as milk, "rich" in lactose and vitamin C, but the content of calcium and total nitrogen is low; class 3 (almost only spring milk) - low content of vitamin C, but high amounts of lactose, iodine number, calcium and total nitrogen; milk of class 4 - is characterized as a milk of low lactose content, high amount of vitamin C, and sour milk is grouped in class 5. Key words: camel milk, descending hierarchical classification, discriminant function analysis, principal component analysis (PCA), ANOVA.