The bottles containing SJ were placed in an electric-heated thermostatic water bath, heated at 80 C for 20 min, and then
rapidly cooled to room temperature. Then,15 bottles were wrapped in black paper (BP), while another 15 were not wrapped. All bottles were placed outdoor during daytime (35 Ce45 C) and nighttime (25 Ce35 C) in summer for 15 d of sunlight exposure. The Ab510, L*, and a* values of the samples from the three wrapped and unwrapped bottles were
determined every 3 d.