Figure 4: Effects of H2S on the contents of ascorbic acid (a), flavonoid (b), total phenolics (c), reducing sugar (d), and soluble protein (e) in grape pulp. Grape clusters were fumigated with 1.0 mM H2S donor NaHS aqueous solution with water as the control groups for 0–7 d. Data are presented as means ± SD (). FW = fresh weight.