Answers are grounded in this paper and cite their sources.
Bitterness and astringency of three concentrations of grape seed phenolic extract were evaluated in a model system using standard sensory testing procedures. For phenolic concentrations of 25, 80 and 135 mg/l (gallic acid equivalent), the ratings for astringency, respectively 2.14, 2.91 and 3.62, increased with phenolic concentration increase (p < 0.01). The bitterness ratings for the three phenolic concentrations, respectively 4.36, 5.16, and 4.99, however, were not significantly different from each other.
No takes yet. Share an insight, caveat, or question.
Arnold et al. (1978) studied this question.
Synapse has enriched 10 related papers. Consider them for comparative context: