Influence of initial pH on hydrogen production from cheese whey.
Batch experiments were conducted to investigate the effect of initial pH, between 5 and 10, on fermentative hydrogen production from crude cheese whey (87.5% (v/v) by Clostridium saccharoperbutylacetonicum). Hydrogen was produced over the range of pH studied. The hydrogen production rate and yield peaked at an initial pH 6 and then steadily decreased as the pH increased. The highest rate and yield were 28.3 mlh(-1) and 7.89 mmolg(-1) lactose, respectively. Sugar consumption was unaffected between pH 5 and 9 and remained at 97%. All final pHs were acidic and increased alongside the initial pH. There was no correlation between the initial pH and the fermentation time; the times were shorter (50-52 h) between pH 6 and 8, and longer (62-82 h) outside this range. A modified Gompertz equation adequately described fermentative hydrogen production from cheese whey. The respective maximum hydrogen production rate and hydrogen potential at an optimal pH of 6 were 47.07 mlh(-1) and 1,432 ml. Lag phase times were much longer at acidic pHs than at alkaline pHs.
Ferchichi
Mongi
M
Research and Development Department, KAM Biotechnology Ltd., #101 9710-187 St., Surrey, British Columbia, Canada V3N 4N6.
Crabbe
Edward
E
Gil
Gwang-Hoon
GH
Hintz
William
W
Almadidy
Amer
A
D002611:Cheese; D003013:Clostridium / Q000254:growth & development*; D006859:Hydrogen / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D014865:Waste Disposal, Fluid
D006859:Hydrogen