This is practical advice, not a blinded sensory experiment. Palm rubbing and viscosity judgments are uncontrolled; four or five drops per dash is not a universal calibrated unit. For our own work, retain actual dose, vessel and serving context rather than importing a nominal dash as milliliters.
Buying and tasting bitters; dosing discussion.
The author proposes examining aroma, tasting a diluted sample and then trying the bitters in a familiar finished cocktail. He notes that bottle and cap designs affect a dash and suggests consistent dispensing vessels. His text also distinguishes drops, dashes and floating additions.
65
63
Buying and tasting bitters; dosing discussion.
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Evidence
The author proposes examining aroma, tasting a diluted sample and then trying the bitters in a familiar finished cocktail. He notes that bottle and cap designs affect a dash and suggests consistent dispensing vessels. His text also distinguishes drops, dashes and floating additions.
Location and context
Source No access. PDF 63–65; Buying and tasting bitters; dosing discussion.
Locators refer to the supplied PDF, not print pagination or ebook index anchors.
Annotation
This is practical advice, not a blinded sensory experiment. Palm rubbing and viscosity judgments are uncontrolled; four or five drops per dash is not a universal calibrated unit. For our own work, retain actual dose, vessel and serving context rather than importing a nominal dash as milliliters.
Literature Note 
Verification checklist
Verified means source fidelity, not universal factual certification. Native page presentation settings remain unverified.