# Barley water

**Acqua d’orzo**

**Known today as.** A thin decoction of barley.

Kind: Food & Drink

## What did Canale use it for?

The base of the mildest vomits, or rich meat broth in its place (ch. 5).

## What does modern science say?

A soothing, demulcent drink, the vehicle here for the other ingredients.

## Pharmacognosy and toxicology

- **beta-glucan**: a soluble fibre
- **starch**: about 80 per cent of pearl barley
- **B vitamins**: niacin and thiamine

**Mechanism.** A bland, demulcent, nourishing drink, given in fevers and catarrhs and to dilute cow’s milk for infants; barley beta-glucan, at 3 g a day, lowers blood cholesterol, the claim authorised for barley in the European Union.

**Dose.** A food.

**Standing.** A food; the European Food Safety Authority concluded in 2011 that barley beta-glucans lower LDL cholesterol, and the claim was authorised in 2012.

## What lore surrounds it?

Strained barley water, *ptisane*, was one of the great remedies of Hippocratic medicine. Hippocrates wanted the barley “well boiled,” since in the boiling it swells as much as it can and so does not swell in the bowels; according to the food historian of *Pass the Flamingo*, Galen repeated the warning centuries later and named flavourings for it, olive oil, salt, cumin, honeyed wine, and vinegar, though he preferred dill and leeks. The same writer notes that water boiled with grain would have been safer to drink than fresh water.

## What did the older authorities say?

**Pliny.** Of ptisan, the barley gruel of the Greeks, he says they “have written in such high terms of the praises of ptisan” that the Roman alica cannot be old; he gives nettle taken with a ptisan to ease expectoration, bulbs of asphodel boiled with a ptisan for consumption, and the smooth acanthus “boiled with the food, a ptisan more particularly,” for ruptures and spasms.

## Sources

- Pass the Flamingo, on ancient barley water.
- Pliny the Elder, *Natural History* 22.61, 22.15, 22.32, 22.34, trans. J. Bostock & H. T. Riley (1855), Perseus Digital Library.
- Hippocrates. *On Regimen in Acute Diseases*, trans. F. Adams (1849). Wikisource.
- European Commission (2012). Commission Regulation (EU) No 1048/2012 of 8 November 2012 on the authorisation of a health claim made on foods and referring to the reduction of disease risk. *Official Journal of the European Union* L 310: 38–40.
- “Beta-glucan.” *Wikipedia* (read 2 October 2026).
- Canale, F. (1622). *Del modo di conoscer et sanare i maleficiati*. Brescia.

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*Barley water.* In *Materia Medica*, edited by B. C. P. Statema. Version 1, revised 2026-10-03. The Thinking Press. https://thethinkingpress.org/materia-medica/barley-water

Historical description, not medical advice.