Home › The Principles of Cookery › SOY, CHINESE (another way)
SOY, CHINESE (another way)
Thirty-five pounds of the shelled pulse are washed in cold water, and boiled in water enough to cover them until they are sufficiently tender, which is ascertained by squeezing them between the finger and thumb. This requires only a few minutes to effect. They are then drained in a sieve, but, whilst still wet, are mixed with a portion of meal made of the same pulse, ground, which an Anglo-Indian, if he were here to see it, would immediately pronounce to be "ground gram." In this meal they are stirred until the surface of each bean is covered. The mass is now laid upon mats to the thickness of about two inches, and the beans are left to dry until the surface of the mass begins to appear mouldy. They are then dried by gradual heat in slow stoves, until they can bear the stroke of a mallet, when they are rubbed with the hand or with a hard brush to free them from the meal. Earthen pans, ready prepared, now receive them in equal portions, and a pickle is made with twenty pounds of salt dissolved in five times its weight of water, which is equally divided among the pans. These are now carefully covered, and kept, during six weeks or more, in a place where the temperature is nearly 100 deg. Fahrenheit. When at length the soluble part of the beans--the part that constitutes the soy--is extracted, this being ascertained by the dark brown colour of the liquid in the pans, the liquid is poured off, and boiled down to the proper consistency. This, however, is not effected until after repeated boilings, during which a quantity of moist sugar, ginger, mace, and black pepper are added in quantities according to the taste of the manufacturers, each having his own peculiar ideas of flavouring, which constitutes the difference between the several brands. After the last boiling, the soy is allowed to stand a few days, then strained, and put into flasks for sale.
This is a factory account rather than a domestic recipe: it describes the commercial manufacture of Chinese soy sauce at a scale of thirty-five pounds of beans at a time. It is worth reading as a document, but it is not a procedure to follow at home.
- The mould step is the problemThe beans are spread on mats and left until the surface "begins to appear mouldy" — that is, inoculated by whatever spores happen to be in the air. Industrial soy sauce uses a pure starter culture of Aspergillus oryzae for exactly this reason: its close relative A. flavus is visually similar and produces aflatoxins, which are heat-stable and are not destroyed by the subsequent boiling.
- Six weeks at blood heatThe pans are held near 100°F for six weeks or more under a cover. The brine here is roughly twenty pounds of salt to a hundred pounds of water, about 17 per cent, which is in the traditional range and does most of the protective work — but the recipe gives no way to verify salt concentration, no pH check and no guidance on what a failed batch looks like. Buy soy sauce, or work from a current recipe with a purchased koji culture and measured brine.
- The pulse"The shelled pulse" is the soybean; the title supplies what the text itself never names. Thirty-five pounds is a commercial batch, not a kitchen quantity.
- "Ground gram"An Anglo-Indian term for flour milled from pulses — chickpea or other gram. Here it is simply soybean meal, dusted over the wet beans so that each one carries a dry coating for the mould to colonise. Modern practice uses roasted cracked wheat for the same purpose.
- "Slow stoves"A low drying heat, held long enough to dry the beans hard rather than to cook them further. The mallet test is a dryness test, not a doneness test.
- What the boiling doesThe dark liquid drawn off the pans is the brine-fermentation liquor, the stage Japanese brewing calls moromi. Repeated boiling concentrates it and stops fermentation; the sugar, ginger, mace and pepper are house seasonings, and the text is candid that these, not the base process, are what distinguished one brand from another.
Soy sauce reached European kitchens through the East India trade well before anyone in Britain understood how it was made, and it was used both at table and as a keeping ingredient in sauces and store ketchups; Worcestershire-type bottled sauces of the nineteenth century commonly listed it. Accounts like this one reflect a Victorian appetite for knowing the industrial process behind an imported article; the writer's aside about what "an Anglo-Indian, if he were here to see it," would call the meal places the observation squarely in the world of colonial commerce, where a British reader was more likely to have met gram flour than soybean flour. The two-stage method described -- a solid mould culture on cooked beans, followed by a long brine fermentation -- is recognisably the traditional East Asian technique still used today, though the frank admission that each manufacturer sweetened and spiced to his own taste suggests the product sold in flasks in London was some way from the plain brewed sauce of its origin.