No abstract

The aim of this study was to investigate the effect of water quality on the main components in Fuding white tea infusions, including catechins, caffeine, theanine and free amino acids. Pure, tap and spring water were tested, and water quality was found to have a distinct effect on the main compounds extracted. Pure water, which was weakly acidic and low in dissolved ions, achieved the highest catechin content, whereas caffeine and theanine, and amino acids, were higher in infusions made with spring and tap water, respectively. Sensory evaluation was performed to evaluate infusion colour, taste and aroma, and sensory quality was similarly influenced by water type, due primarily to differences in dissolved ions. Pure water was more suitable for brewing white tea with superior colour, aroma and taste.

231is study compared four different thawing methods using sensory test with magnitude estimation, Preference test with hedonic scale and physical analyses. The four methods were tap-water, refngeration, microwave reheating, and boiling-water reheating. For physical analyses, there were differences @ 5 0.001) among treatments in drip loss and expressible juice. For drip loss, the microwave reheated samples were the highest and the refrigeration and tap-water treated samples were the lowest. For expressible juice, tap-water and refngerated samples were higher f j~ 5 0.01) than the microwave and boilingwater reheated samples. Microwave and boiling-water reheated samples had higher hardness and chewiness and lower juiciness and fiber-looseness. The refngerated and tap-water thawed samples had reverse sensory properties. NaLve panelists preferred the rmgerated and tap-water treated samples to the microwave and boiling-water reheated samples for juiciness, tenderness, and overall preference. Physical parameters from textural profile analysis were not difSerent among the thawing methods. Expressible juice was the best indicator for sensory hardness, juiciness, fiber-looseness and chewiness among the physical parameters. Usually a quadratic regression model fit best when expressible juice was used to predict sensory textural properties.