Important: Safety Warning
This page describes home-canning methods from before the causes of botulism were understood. Canning low-acid foods without a pressure canner, as described here, can allow the growth of Clostridium botulinum, whose toxin is among the deadliest known. Follow current USDA home-canning guidelines instead.
In addition, this page recommends preserving food with chemicals such as salicylic acid, borax, or formaldehyde. These substances are toxic when eaten, and their use in food is now prohibited.
This information has been left in for historical purposes but should not be acted upon.
Home › The Waldorf Kitchen › Tomato Catsup
Tomato Catsup
Cut a number of tomatoes into slices, put them in a deep earthenware pan in layers, sprinkle over a layer of salt and allow them to remain in the salt for twelve hours. Put them over the fire in a preserving-kettle and allow them to boil until they are quite soft; then strain and squeeze the juice from them in a thin linen cloth. Put the strained juice over the fire with mace, cloves, grated horse-radish and garlic to taste and let it boil rapidly for thirty minutes or so. Remove it from the fire, allow it to get cold, then bottle it, corking the bottles well and dividing the spice equally among the bottles. The addition of a small quantity of salicylic acid will effectually prevent fermentation and mould. Eight grains stirred in after or while boiling will be sufficient for one quart. A piece of blotting-paper made to fit tightly over the catsup and saturated with a concentrated solution of salicylic acid in rum or brandy will help to keep it good. The acid is entirely harmless, with no taste or smell and can be obtained in powder or crystals, the latter being preferred. When this is used, care must be taken never to employ tin or metallic vessels as when it comes in contact with the metal it turns dark. Porcelain-lined vessels are the best.
This is a period ketchup built around a chemical preservative that is no longer permitted in food, and the bottling method offers no protection on its own. The notes below explain why the recipe fails rather than how to rescue it.
- Salicylic acid is not a food preservativeThe recipe calls for eight grains (roughly half a gram) of salicylic acid per quart, plus blotting paper soaked in a concentrated solution of it in rum or brandy. Salicylic acid was progressively driven out of the American food supply in the years following the Food and Drugs Act of 1906 and the Bureau of Chemistry's work on chemical preservatives; it irritates the stomach lining, and salicylates have been implicated in gastric bleeding and, in children, in Reye's syndrome. The claim that it is "entirely harmless" reflects 1890s commercial practice, not evidence.
- The dose is guessworkThe dose is only as good as the measuring -- Eight grains per quart is a weight measure of a crystalline drug to be stirred into a hot liquid. The recipe gives a rate but no way of knowing how much liquid the tomatoes actually yielded after straining, and no margin for error is described anywhere in the method.
- Bottling is not preservingThe catsup is boiled, cooled to room temperature, then poured into corked bottles. Filling cold invites recontamination, corks are not an airtight seal, and no water bath or pressure process follows. The whole preservation burden falls on the chemical, which is exactly why it was added.
- No measured acidityTomatoes sit near the borderline pH for safe water-bath canning, and modern tomato-product recipes specify added lemon juice or citric acid for that reason. This one adds no acid at all beyond what the fruit brings, and adds low-acid horseradish and garlic on top of it, which pushes the mixture the wrong way.
- The salting step is not a cureSliced tomatoes layered with salt for twelve hours in an earthenware pan draw off liquid but do not reach a preserving concentration. That is twelve hours of standing before any heat is applied.
- If you want tomato catsupUse a current tested recipe from a food-safety extension service, which will give you weights, an acidification step, and a processing time and temperature. Do not attempt to substitute a modern preservative into this method.
- One detail worth keepingThe warning against tin and metallic vessels is sound kitchen sense for any long-boiled tomato preparation, salicylic acid or not. Acidic pulp picks up metallic flavour and discolouration from reactive pans; enamelled, stainless or porcelain-lined is right.
Oscar Tschirky, the Waldorf's celebrated maître d'hôtel, published his Cook Book in 1896, and its household chapters record the state of American home preserving in the decade before federal food law. Chemical preservatives were then ordinary commerce: salicylic acid, borax and benzoate of soda were sold to housewives and used heavily by manufacturers, and the confident assurance here that the acid is "entirely harmless, with no taste or smell" is the standard sales language of the period repeated in good faith. Harvey Wiley's Bureau of Chemistry began testing these compounds on human volunteers in 1902, and the resulting pressure produced the Pure Food and Drugs Act of 1906. The catsup itself is older than the tomato version: the word is generally traced to a Southeast Asian fermented fish sauce, kê-tsiap, and English cooks made catsups of mushrooms, walnuts and oysters long before tomatoes took over the name in nineteenth-century America. The mace, cloves, horseradish and garlic here belong to that earlier tradition of a thin, sharp, spiced table sauce rather than to the thick sweet condiment the word now means.