Figure 4: Relationship between water temperature and post-electrolytic DH or ORP. Note: (A) DH exerted a tendency to decrease along with water temperatures above 40°C. The pre-electrolytic DH showed to be below the detection sensitivity limit. At the time of producing hydrogen-water, there was the amount of water of 300 mL. DH was thereafter measured always at 20°C not so as to be deferred and affected by hydrogen-generating temperatures. (B) ORP tended to increase as the water temperature increased. Data were expressed as the mean ± SD. The number of data at each water temperature was three (n = 3) for a typical converged one chosen out of independent three-time-repeated experiments. *P < 0.05, **P < 0.01. DH: Dissolved hydrogen concentration; ORP: oxidation-reduction potential.