Kombucha

One US cup of kombucha weighs 240 grams. Going the other way, 100 grams is about 0.42 cups.

Also called fermented tea, SCOBY tea, booch, kombucha tea, raw kombucha.

TL;DR: **One US cup of kombucha weighs 240 g** — GT's Kombucha and Health-Ade both list 240 g per 8 fl oz serving on their nutrition labels. Density 1.014 g/mL, essentially identical to kefir and just above water. Kombucha sits in the water-density band alongside kefir, milk, buttermilk, and other aqueous fermented liquids. King Arthur does not publish kombucha; it is a beverage rather than a baking ingredient.

Kombucha is a fermented tea beverage made from sweetened *Camellia sinensis* tea (black, green, or white) and a SCOBY — Symbiotic Culture Of Bacteria and Yeast — dominated by acetic-acid bacteria (*Gluconacetobacter*, *Komagataeibacter*) and osmotolerant yeasts (*Saccharomyces*, *Zygosaccharomyces*, *Brettanomyces*). The culture floats as a cellulose mat on the tea's surface during fermentation, giving rise to the traditional English name 'mushroom tea' (though it is neither a mushroom nor closely related to fungi). Origins are traditionally traced to Manchuria around 200 BC, with documented consumption across East Asia, Russia, and Eastern Europe for centuries before the American commercial boom that began in the mid-1990s. GT Dave founded GT's Kombucha in Beverly Hills in 1995 after making kombucha for his mother during her breast cancer treatment; GT's remains the dominant US brand, joined in the 2010s by Health-Ade, Better Booch, Brew Dr., Kevita, Suja, and Remedy.

The density data is exceptionally clean. GT's Organic Raw Kombucha nutrition label lists 8 fl oz serving = 240 g across multiple flavor variants (Original, Trilogy, Gingerade). Health-Ade Kombucha (verified via SnapCalorie) lists 240 g serving = 60 calories with 14 g total carbohydrate. Both figures yield density 1.014 g/mL (240 g ÷ 236.588 mL), slightly above pure water (1.000 g/mL) due to dissolved organic acids, residual sugar, and trace CO2. The physical prediction confirms this: post-fermentation kombucha is 90-95% water, 1-3% residual sugars (sucrose, fructose, glucose in various ratios depending on fermentation length), 1-2% organic acids (acetic, gluconic, glucuronic, lactic), 0.5-1% ethanol (kept below 0.5% ABV for commercial non-alcoholic classification under US TTB regulations), plus trace tea polyphenols and B-vitamins produced by the yeasts. Standard sucrose-water tables predict 1.01-1.02 g/mL for solutions in this concentration range, matching observation within measurement precision.

Brand variance in residual sugar is substantial — Remedy runs 0-2 g per 8 fl oz, GT's 3-7 g, Humm 8-12 g, Brew Dr. 8-14 g, Health-Ade 8-16 g, Kevita 9-11 g — but the density impact is trivial. The difference between 0% and 4% dissolved sugar is only 0.017 g/mL, well below typical kitchen-scale precision, so a cup of any commercial kombucha weighs 240 g within any measurable tolerance. Homemade kombucha varies with fermentation length: a 7-day ferment retains 3-5% residual sugar (density ~1.02 g/mL, 241 g/cup) while a 21-day ferment drops to 0-1% (density ~1.005 g/mL, 238 g/cup). Neither difference matters for practical purposes.

In the ExactCups liquid category, kombucha (240 g/cup) joins the water-density band alongside kefir (240 g/cup, S17), whole milk (245 g/cup), buttermilk (240 g/cup), and pure water (237 g/cup). All aqueous liquids with modest dissolved solids cluster in this narrow 237-245 g/cup range regardless of what specifically is dissolved — the physics of dilute aqueous solutions dominates over compositional detail. Kombucha and kefir sitting at identical density despite completely different substrates (tea vs milk) and different microbial communities (SCOBY vs kefir grains) is a nice illustration: both metabolic processes convert similar amounts of carbohydrate substrate into similar amounts of acid + gas + trace solids, producing similar final density even though the flavor profiles are worlds apart.

Practical baker recommendation: kombucha weighs 240 g per US cup, matching water within 1%. When substituting for water in bread doughs (some sourdough bakers use kombucha for extra acidity), use equal weight with no hydration adjustment needed. When substituting for buttermilk in pancake or biscuit recipes, use equal weight — the acidity is similar enough to trigger baking soda leavening reactions, though the flavor will lean tea-tangy rather than dairy-tangy. Kombucha's live cultures die at cooking temperatures above about 45°C (113°F), so any probiotic benefit is lost in baked applications; use raw kombucha for cocktails, dressings, and cold applications when the live cultures matter.