Abstract:
Liposoluble pigments, predominantly sourced from natural extracts, are celebrated for their exceptional safety profile and a wide array of physiological benefits. Nevertheless, their inherent chemical reactivity compromises their stability, posing significant challenges for their application. Addressing this issue, the current study investigated the efficacy of lake technology, employing
β-carotene as a prototypical pigment, to bolster the stability of liposoluble pigments.
β-Carotene-calcium carbonate lakes were prepared, with the preparation process optimized through single-factor experiments and response surface methodology. Comprehensive characterization techniques, including laser particle size analysis, SEM, XRD, and Raman spectroscopy, were employed to elucidate the physicochemical properties of the synthesized lake. The findings delineated that the ideal conditions for the formation of
β-carotene-calcium carbonate lakes encompassed a pH of 9.9, a shear speed of 15400 r/min, a dispersion shear duration of 60 s, a co-precipitation shear time of 120 s, and a temperature of 45 ℃. Under these optimized parameters, the lake demonstrated an impressive adsorption capacity of 23.525 mg/g. Notably, the shear process markedly diminished the particle size of the
β-carotene suspensions, thereby facilitating the efficient formation of the lake. The calcium carbonate within the lake predominantly exhibited the calcite crystal morphology, with some particles showing signs of fracturing due to the applied shear forces. XRD analysis confirmed calcite as the crystalline form of the calcium carbonate present in the lake. Furthermore, Raman spectroscopy corroborated this finding and revealed the absence of chemical bonds between
β-carotene and calcium carbonate, suggesting the predominance of non-covalent interactions. In summary, the study demonstrated that under carefully optimized conditions, calcium carbonate, presented in the calcite form, served as an effective carrier for
β-carotene, with shear processes playing a pivotal role in reducing the particle size of the pigments. These pigments were anchored to calcium carbonate via non-covalent forces, presenting a promising avenue for the development of liposoluble pigment lakes. This research not only provides a valuable reference for the fabrication of lakes for liposoluble pigments, but also introduces a novel methodology for the enhancement of the stability of these pigments.