Quantitative Estimation of Casein in Different Milk Samples

Abstract

Milk is an important part of human life and supposed to be a nutritious food which contain about 80% proteins. Milk proteins consist of 80% casein (soluble protein), 2-8% lactose (milk fat) and remaining is whey (byproduct of cheese and casein manufacture). Casein is more important and contain almost all essential amino acids. The purpose of the present work was to estimate the amount of casein in different milk samples including natural milk (cow, buffalo, sheep and goat) both in boiled and un-boiled form and ultra-high temperature processed (Nestle Milk pack, Olper's and Everyday Liquid) milk. In all the milk samples Nestle Milk pack contains high casein (g/100mL) 7.39±0.021 while cow milk contains lowest casein (g/100mL) 4.91±0.036 in un-boiled form and 4.75±0.025 in boiled form. Milk is supposed to be more beneficial if quantity of casein increases. From this research it is concluded that sheep milk is more beneficial with casein percentage 5.64±0.01 in un-boiled milk and 5.52±0.021 in boiled milk sample in case of natural milk samples while in tetra-packs Nestle Milk pack is beneficial with casein percentage 7.18±0.021 and 7.39±0.021 casein (g/100mL).

Comparative Study of Casein Protein Content of Milk of Different Domesticated Cow, Buffalo and Goat Breeds from South-West Part of Karjat Tehsil, Ahmednagar District, Maharashtra, India

“…2). The amount of casein protein obtained in present study shows resemblance with the values of casein found by Jabeen et al [10] for milk samples of cow, buffalo and goat.…”

“…The method of precipitation of casein protein in milk by lowering the pH of milk to 4.6 (by using 2% HCl), the precipitated casein was filtered and dried in oven at 40˚C for 24 hours and then dry weight of casein was measured with digital balance. The same methodology was used by Patil et al [13], Jamil et al [14], Kumaresan et al [15], Jabeen et al [10].…”

“…The casein is proved to be the major constituent of the milk and it is almost found 80 % of total milk protein [10]. The casein micelles that are being precipitated at isoelectric pH contains αS1 casein, αS2 casein, β casein and κ casein.…”

Genetic and Non-Genetic Factors Affecting Test Day Milk Yield and Milk Composition Traits in Crossbred Dairy Cattle in Ethiopia

“…The content of casein previously reported was 28.26 mg/ml by Cozma et al (2011), 32.66 mg/ml by Maurmayr et al (2018), and 28.36 ml/ml by Amalfitano et al (2020), all the reported values being less than ≤ 50% group of cows (37.77 mg/ml), while greater than 25.61 mg/ml was found in the >87.5% group of cows in this study. Jabeen et al (2020) reported 4.91g (49.1 mg/ml) using acid precipitation methods in cow's milk in Pakistan; this is greater than the current study reported for all genetic groups. The value of whey protein previously reported was 6.99 mg/ ml by Maurmayr et al (2018) and 5.42 mg/ml by Amalfitano et al (2020); both reported results lower than 9.44 mg/ml found in ≤ 50% and higher than 4.54 mg/ml found in >87.5% of cows in this study.…”

“…Casein precipitated, and the supernatant was decanted using 45µm filter paper and a funnel. The precipitate was washed with distilled water to remove the salts and then with ethanol to remove the remaining fats then dried and weighed (Jabeen et al, 2020). Whey protein was obtained by subtracting casein from total protein.…”