• The Korean Journal of Food & Health Convergence
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• v.8 no.5
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• pp.11-20
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• 2022

Honey was diluted with different percentages of water and was analysed rheologically at room temperature of 27℃. The rheological profiles of pure and impure honey samples were measured at low shear rates (0.01-4.16s^-1). This work developed a structural kinetic model, which correlated well with the rheological data. The new model was used to categorise honey samples using their average molecular weights as one of the distinctive properties. Also, the kinetics order in the new model predicts the number of active components in the "honey" undergoing deformation. Honey produced third order kinetics to depict the monomers, oligomers and water content in honey. Pure honey exhibits peculiar non-Newtonian rheological behaviour. The behaviour of water is Newtonian. Dilution of honey with different percentages of water turns the resulting fluid Newtonian from 10% dilution with water. This study analysed the antibacterial activities of honey and serially adulterated samples against Staphylococcus aureus and Pseudomonas aeruginosa. The antibacterial analyses of honey were conducted using Kirby Bauer's well diffusion method. The results indicated that pure honey exhibited a zone of inhibition against both organisms. Also, the diameter of the zone of inhibition decreased with increasing dilution of honey, suggesting a correlation with the rheological method.

• Food Science and Preservation
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• v.17 no.1
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• pp.66-71
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• 2010

In the Joseon Dynasty, various fruit teas were popularized to promote health, with spread of Donguibogam and Hyangyag gugeupbang. As interest in fruit tea has recently increased, studies on its manufacture have become necessary. We used response surface analysis for rediscovery and commercialization of grape tea. Major materials of traditional grape tea are grape juice, pear juice, ginger juice, and honey, and the sugar contents of these materials were 12.3, 14.1, 3.3 and 75 $^{\circ}Brix$, respectively. When sensory examinations were conducted with subjects aged 40-60 years, the difference between dilution ratios of 100% and 150% was not significant, but tea diluted by 150% showed somewhat higher scores than did tea diluted by 100%. Ginger taste and sweetness were found to have the greatest effect on overall acceptance. Regression analysis on color, flavor, taste, and overall acceptance values, with reference to ginger juice and honey as independent variables, revealed that the $R^2$ values were 0.8411, 0.6717, 0.9499, and 0.9015, respectively. Contour maps were superimposed to obtain an optimal combination of ingredients for traditional grape tea, and the indicated levels of ginger juice and honey were 0.46-0.69% and 3.85-5.20%, in combination with grape juice, pear juice, and water concentrations of 28%, 9% and 60% (all w/w), respectively. Thus, it is now possible to prepare traditional grape tea.