Water in the glass.

Does the water you add change what tasters notice in a whiskey?

Status: Opens with the Water Course
Protocol: Version 1.0, 2026-10-18
Consent: S.water.v2
Investigator: John Schuster, Drunken Unicorn Productions
Preregistration: Being posted to the Open Science Framework; the link will appear here
Ethics review: Not yet reviewed; we intend independent review before any results are published
Target: At least 109 water triangles from at least 25 tasters
Runs until: The target is reached, or 2029-10-18

Why this study

Distilleries proof with treated water; drinkers add whatever comes out of the tap. Our literature review found no published proofing-water specification and no measured sensory threshold for common minerals in whiskey. The one trained-panel test of water type in spirits (Wang & Cadwallader, 2024) found no effect on taste or mouthfeel, and its panel did not assess aroma. Savorant’s course has tasters nose every glass before tasting, which tests the part that study left out.

What taking part means

Work through the Water Course when it opens, including its water triangle rounds, and note which water you used. Until the course opens, joining just means you’re in from the first day. Your Water Course answers, your water triangle results, which water you used, and the descriptors and measures from those sessions.

To join: in the app, turn on research contribution in Settings → Research, then open Water in the glass under Research studies, read it, and agree. You can leave with one tap.

Hypotheses

H1 (primary). In water triangles (the same whiskey at the same dilution, two glasses with one water and one with another), tasters identify the odd glass more often than chance (one in three).
H2 (secondary). Waters are distinguished more often when they differ more in total dissolved solids.

Design

Within-taster sensory discrimination, triangle method, using the Water Course’s four-water kit (distilled, and three bottled waters spanning total dissolved solids from about 70 to about 350 mg/L).

Who can take part. Adults 21 or older in the United States who use Savorant, have research contribution turned on, and have joined this study in the app.

Outcomes

Primary. Proportion of water triangles answered correctly, with the proportion of discriminators (pd) and its 95% CI.

Secondary and exploratory.

Correct rate by water pair, against the difference in total dissolved solids.
Waters tasted alone (no whiskey): correct rate, exploratory.
Descriptors and structure ratings that differ between waters, exploratory.

Sample size

At least 109 water triangles from at least 25 tasters. An exact one-sided binomial test needs 87 trials to detect pd = 20% (p = 0.467) with 80% power at α = 0.05; multiplied by a design effect of 1.25 (six trials per taster, intraclass correlation 0.05) that is 109.

Analysis

Mixed-effects logistic regression of correct (yes/no) with a random intercept for taster; the intercept is tested against logit(1/3), one-sided, α = 0.05, as is standard for the triangle test. pd = (p − 1/3) / (2/3) is reported with a 95% CI.

Only data filed after a taster joins is used.

When a study reports more than one secondary test, p-values are adjusted with the Holm method.

Limitations we know about

Home conditions, self-reported water, and kit waters chosen by availability rather than to isolate single minerals. Tasters who join may already believe water matters.

Standards every Savorant study follows

Preregistration. This page is the protocol of record, versioned and dated, and is posted to the Open Science Framework (OSF) before any study data is analyzed. Hypotheses, outcomes, sample size and analysis are fixed here in advance.
Primary and secondary outcomes. Each study names one primary outcome, tested at the stated alpha. Everything else is labeled secondary or exploratory and reported as such, with effect sizes and 95% confidence intervals rather than bare p-values.
No peeking. No interim analysis of the outcomes. The only checks before the sample size is reached are for data quality (duplicates, impossible values), and they never look at results.
Repeated measures. One taster contributes many rounds, so analyses use mixed-effects models with the taster as a random effect, or per-taster summaries, never pooled rounds treated as independent.
Exact methods for small counts. Triangle results are analyzed against the exact binomial with chance at one in three, the way ISO 4120 sets out the triangle test, adapted here for repeated measures.
Exclusions. Rounds are excluded only for the reasons listed in advance: test accounts, the founder’s accounts, rounds filed in a preview build, and duplicates. Every exclusion is counted and reported.
Missing data. Tasters who stop early are kept for every analysis their data supports. The number who stop, and when, is reported.
Deviations. Any change after data collection starts is logged on this page as a dated amendment with its reason, and reported in the paper.
Reporting. Results are reported following the STROBE guideline for observational studies, with the analysis code published alongside.
Conflict of interest. The study is run by the company that sells the app. Preregistration, publishing regardless of outcome, and public analysis code are how that interest is kept out of the result.

The consent you agree to

This is the exact text shown in the app before you join.

Amendments

None. This is the first version of the protocol.

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