Relationship between somatic cell count and milk casein level obtained by two different methods

Abstract

Musayeva K., Sederevičius A., Želvytė R., Monkevičienė I., Beliavska-Aleksiejūnė D., Stankevičius R. (2016): Relationship between somatic cell count and milk casein level obtained by two different methods. Czech J. Food Sci., 34: 47-51.The purpose of the present work was to investigate the impact of somatic cell count (SCC) on the content of milk casein and to compare the sensitivity of different methods for the determination of the casein level in milk. Two different methods were employed in order to determine the casein level: routine method -infrared spectrophotometry and reference method -Kjeldahl. Data array of 26, 169 milk samples of the livestock control was used to analyse milk casein variation by SCC limits. Mean casein values (investigated by the routine method) varied from 2.47% to 2.8% (2.65 ± 0.09) and casein number (in % on crude protein basis) -CN% varied from 79.5% to 81.1%. The present analysis showed that the relation between SCC and casein content obtained by the routine method correlated significantly (Pearson correlation r p = 0.644, P < 0.05, r 2 = 0.414, Spearman correlation r s = 0.786, P < 0.05). Evaluated results obtained by the least squares method, and linear approximation of variation indicators presented a noticeable decline in casein percentage -0.27%, when SCC increased by 80 × 10 3 /ml, but only when the studies were done by the reference method.

Short communication: Caseins and α-lactalbumin content of camel milk (Camelus dromedarius) determined by capillary electrophoresis

“…Here, SCC correlated negatively with β-casein (r = −0.325, P < 0.01) and the percentage of caseins in total proteins (r = −0.39, P < 0.01), but it had a highly positive correlation with κ-casein (r = 0.76, P < 0.01). This agrees with Musayeva et al (2016), who found that the percentage of caseins in total proteins decreased when the SCC increased in BM. Subclinical and clinical mastitis are known to be associated with increased activity of plasmin, the major milk proteolytic enzyme (Le Roux et al, 1995;Stelwagen, 2011).…”

“…The results showed a weak positive correlation (r = 0.266, P < 0.01) between SCC and total protein, in agreement with previous results (Hamed et al, 2012). Somatic cell count, a quantitative index of mastitis condition of ruminants, has been linked with a decrease in casein content, proteolysis, and changes in the protein fraction distribution in BM (Le Roux et al, 1995;Musayeva et al, 2016;Johansson et al, 2017). Here, SCC correlated negatively with β-casein (r = −0.325, P < 0.01) and the percentage of caseins in total proteins (r = −0.39, P < 0.01), but it had a highly positive correlation with κ-casein (r = 0.76, P < 0.01).…”

Destabilization of UHT milk by protease AprX from Pseudomonas fluorescens and plasmin

“…Milk contains a large number of native enzymes with differing specificity, stability and impact on product quality (Kelly & Fox, 2006). Plasmin (EC 3.4.21.7), with its zymogen plasminogen and other parts of the complex enzyme system, constitute the major native protease system in milk, and has been reported to be correlated with udder health, as indicated by the somatic cell count (SCC) (Ramos, Costa, Pinto, Pinto & Abreu, 2015;Musayeva, Sederevičius, Želvytė, Monkevičienė, Beliavska-aleksiejūnė & Stankevičius, 2016). This protease system exhibits a high thermal stability and can remain partially active after the UHT treatment; therefore, the plasmin system has been closely linked to physicochemical deterioration of UHT milk (Kohlmann, Nielsen & Ladisch, 1991;Kelly & Foley, 1997;Rauh et al, 2014b).…”

Quantitative Estimation of Casein in Different Milk Samples

“…It is the richest and appreciable source of energy for infant mammals including human beings [5]. Milk is an excellent source of proteins, fats, vitamins, minerals and antioxidants [6]. It is a versatile ingredient used for the production of many dairy products i.e.…”