The experiments of whether water should be added in samples pretreatment and titration in the determination of the acidity of maternal fermented grains were done. The experimental results showed that 1. water added in maternal fermented grains for stirring, then stirring again 15 min after steeping, total steeping time as 30min, then the upper clean liquid extracted without filtration; 2. whether water added or not in the titration had few effects on final judgment, however, water addition in the titration was better because it co...
