Increasing calcium solubility from whey mineral residues by combining gluconate and delta-gluconolactone

Author(s)

de Zawadzki, Andressa ^[1] ; Skibsted, Leif H. ^[1]

Affiliation

^[1] Univ Copenhagen, Dept Food Sci, Rolighedsvej 26, DK-1958 Frederiksberg C - Denmark

• Document type: Journal article
• Source: INTERNATIONAL DAIRY JOURNAL; v. 99, DEC 2019.
• Web of Science Citations: 0

Abstract

Insoluble milk mineral residues from whey processing, dominated by hydroxyapatite and calcium hydrogen phosphate, dissolved isothermally in aqueous gluconate/delta-gluconolactone, spontaneously forming solutions supersaturated in both calcium hydrogen phosphate and calcium gluconate. Calcium concentration of maximally supersaturated solutions was proportional to gluconate concentration, indicating gluconate assisted dissolution, while gluconolactone increased calcium available for dissolution and supersaturation. Precipitation of calcium gluconate, rather than of calcium hydrogen phosphate, was critical for supersaturation robustness. For calcium gluconate ionic product:solubility product of calcium gluconate ratios <12, the supersaturated solutions had a lag phase for precipitation of several weeks, which increased to several months by addition of solid calcium saccharate prior to dissolution of the mineral residues. Such supersaturated solutions with up to 7 g calcium L-1, corresponding to a factor of supersaturation of >100 times compared with equilibrium calcium hydrogen phosphate solubility, may be exploited for increasing calcium availability of whey mineral based functional foods. (C) 2019 Elsevier Ltd. All rights reserved. (AU)

• FAPESP's process: 17/01189-0 - Novel aging: technologies and solutions to manufacture novel dairy products for healthy aging
• Grantee: Daniel Rodrigues Cardoso
• Support Opportunities: Research Projects - Thematic Grants