Ingredient · Ingredients
Rhubarb
Printed from https://gourmetgastronomer.com/ingredients/rhubarb/
A sour petiole used as fruit in jam kettles — listed in Group I of U.S. jam identity, where the regulation’s word “fruit” includes this vegetable.
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Rhubarb is a leaf stalk. The kitchen treats it as fruit because it is sour and takes sugar. 21 CFR 150.160 lists rhubarb in Group I and says that for that section the word “fruit” includes the vegetables specified in the paragraph 1. The identity is not a botanical lecture.
Ohio’s three-column pectin chart does not include rhubarb. Gel is still Pectin, Sugar, and Acidity on Jam. Strawberry is the usual companion fruit in American pots; that pairing is culinary, not a tested formula.
NCHFP’s acid-food list is why a rhubarb spread can be a boiling-water candidate when it is a tested jam — fruits, pickles, and jams sit at or below pH 4.6 in that guidance 2. Use a tested process for the time. Leaves are not food; the edible portion is the petiole.
What to notice. Snap, strings, sharp sour. Green versus red is color, not a gel law. Canning for the jar.
At a glance
- Also called
- rhubarbs
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Cited in this article
- 21 CFR § 150.160 — Fruit preserves and jams — U.S. Food and Drug Administration (text via Cornell LII) — U.S. standard of identity. Group I fruit-to-sugar 47:55; other cases 45:55; finished soluble solids not less than 65 percent. Kitchen usage and this labeling standard are not the same thing.
- Ensuring Safe Canned Foods — National Center for Home Food Preservation, University of Georgia — Adapted from USDA Complete Guide to Home Canning, AIB No. 539 (revised 2015). Acid vs low-acid foods, pH 4.6, botulinum, boiling-water vs pressure canning.
Updated 2026-08-26. gg:ingredient:rhubarb · CC BY 4.0
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Gourmet Gastronomer. "Rhubarb." Gourmet Gastronomer. Updated August 26, 2026. https://gourmetgastronomer.com/ingredients/rhubarb/.
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