“In addition, tannin sources containing both HT and CT were more potent in suppressing methanogenesis than those containing only HT.”
“ Tannin also suppressed the population of methanogenic … average decrease of 11.6% in HT incubations (15.8, 7.09, and 12.0 in HT1, HT2, and HT3) and 28.6% in incubations … in HT + CT1, HT + CT2, and HT + CT3) when compared with incubations containing added polyethylene glycol-6000.”