Technical note: Development and validation of a new method for the quantification of soluble and micellar calcium, magnesium, and potassium in milk

Abstract

Milk mineral content is a key trait for its role in dairy processes such as cheese-making, its use as source of minerals for newborns, and for all traits involving salt-protein interactions. This study investigated a new method for measuring mineral partition between soluble and micellar fractions in bovine milk after rennet coagulation. A new whey dilution step was added to correct the quantification bias due to whey trapped in curd and excluded volume. Moreover, the proposed method allowed the quantification of the diffusible volume after milk coagulation. Milk mineral content and concentration in whey, and diluted whey were quantified by acid digestion and inductively coupled plasma optical emission spectrometry. The repeatability of the method for micellar Ca, Mg, and K was between 2.07 and 8.96%, whereas reproducibility ranged from 4.01 to 9.44%. Recovery of total milk minerals over 3 spiking levels ranged from 92 to 97%. The proposed method provided an accurate estimation of micellar and soluble minerals in milk, and curd diffusible volume.

Are cheese-making properties of dual purpose cattle impaired by highland grazing? A case study using Aosta Red Pied cows

“…Thus, the unfavourable effect of HI on RCT found in the present study could be partially due to the concomitantly higher SCS, because a high density of somatic cells is antagonistic in this respect (Politis and Ng-Kwai-Hang, 1988). A sufficiently high Ca content of the milk is also important for a favourable MCP (Franzoi et al 2017). The grass from LO pasture was richer in Ca than that from the HI pasture (Table 1), but cows always received a Ca containing mineral feed and Ca contents of the milk are difficult to influence by diet anyway as the cow tries to keep milk composition stable for their offspring (Gaucheron 2005).…”

Rheology and Microstructures of Rennet Gels from Differently Heated Goat Milk

“…It could be hypothesized that in the case of the goat milk and heating regimes applied in this study, higher initial levels of Ca 2+ compared to cow milk appeared to be sufficient for the undisturbed rennet coagulation to occur, even after a certain amount of it precipitated during heating. By engaging the method for quantification of soluble and micellar calcium fractions [36], calcium distribution in goat milk after different heat treatments could be conducted, and the proposed hypothesis could be tested.…”

Performance of Skim Goat Milk Mineral Content Subjected to the Block Freeze Concentration Process

“…The concentration of Ca and Mg were higher than those reported by Moreno-Montoro et al [11] during the ultrafiltration of skimmed goat milk. Ca and Mg contents are related to casein structure, which is primarily involved in the coagulation process and curd formation and a higher concentration of Ca in the milk could decrease the rennet clotting time and increase the curd firmness [10,[28][29][30]. The P content showed no difference (P > 0.05) between the initial skim goat milk and concentrated fraction (CG1, CG2, and CG3).…”

“…Minerals are fundamental for human health, as they are required for many physiological functions such as tissue growth, regulation of enzyme activities, blood clotting, and to facility of membrane transport of essential nutrients [8,9]. Besides their effects on health, minerals influence milk technological traits, casein micelle structure and aggregation, rennet coagulation time, curd structure, and cheese yield [8,[10][11].…”