• Journal of the Korean Chemical Society
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• v.66 no.4
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• pp.278-283
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• 2022

Using the Kirkwood's method, the free energy of a binary lattice solution consisting of two identical interpenetrating sublattices, such as a simple cubic lattice or a body-centered cubic lattice, was calculated up to the tenth order of the reciprocal of absolute temperature. Using this, liquid-liquid coexistence curves and critical solution temperatures for the binary lattice solutions were calculated to quantitatively investigate the effect of non-random mixing of molecules. And it was shown that the coexistence curve of the simple cubic lattice solution was in good agreement with the Monte-Carlo computer simulation result.

• Korean Journal of Food Science and Technology
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• v.45 no.3
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• pp.299-304
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• 2013

The major hydrophilic bioactive compounds (chlorogenic acid, caffeine, total phenolics, and flavonoids) and the antioxidant capacity in a single size were evaluated for regular coffee varieties commercially available in Korea. The content of total phenols (63.83-110.12 mg gallic acid equivalents) and flavonoids (35.27-69.27 mg catechin equivalents) were spectrophotometrically determined, and the content of chlorogenic acid (5.17-69.78 mg) and caffeine (74.38-146.32 mg) were determined using HPLC-UV. All varieties of regular coffee studied showed antioxidant potential (88.78-487.52 mg trolox equivalents/serving size), which was conferred by their concentrations of phenolic compounds, caffeine and chlorogenic acid. There were significant (p<0.01) correlations between the total phenolics ($r^2$=0.732) and flavonoids ($r^2$=0.8705) and the antioxidant capacity, suggesting that these components were likely a significant contributor to the antioxidant capacity of commercial regular coffee brews.