摘要：The effect of preferment liquor, temperature and duration of fermentation on the cyanide content as well as the functional and sensory properties of gari were studied. Cassava roots (local cassava variety) were peeled washed and grated and immediately seeded with 3-day spent liquor concentrations (0.0, 5.0, 10.0, 15.0 and 20.0% (m/v)) in thoroughly washed plastic containers. These were kept in ambient environment (±30°C) to ferment; samples were with drawn at 12, 24, 36, 48 and 72 h intervals and processed into gari. The processes were repeated for controlled fermentation at 35 and 40°C using a water bath. The samples were analyzed for pH, titratable acidity, residual cyanide and sensory evaluation (taste, appearance and general acceptability). The results show that increasing concentration of spent liquor significantly lowered residual cyanide, decreased pH and increased the titratable acid. The addition of preferment reduced the HCN concentration to 9.92 mg HCN kg-1 for 15.0% and 8.36 mg HCN kg-1 for 20.0% samples. Similarly, 15% preferment liquor, gave the highest swelling index-26.19 when, fermented at 30°C. However, the value decreased to 23.12 and 22.71 when fermented at 35 and 40°C. The sample fermented at 5.0% gave the best performance (0.6047 g cm-3) for the bulk density. The sample from 5.0% preferment treatment also gave the best performance in terms of appearance (6.0), taste (6.1) and general acceptability (6.1). The titratable acidity increased with increase in preferment concentration. Moreover, limiting the spent liquor to 5.0%, temperature, at 35°C and duration of fermentation, at 48 h gave best performance for functional and sensory qualities and also guarantees food safety .
