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Rennet, Substitute For
It sometimes happens that no rennet sufficiently good for curdling milk can be obtained, hence various plants have been advantageously employed for this purpose. The principal of these are the flowers of the yellow ladies' bed-straw used in England, and the eardown in Spain. A strong infusion is made of the flowers or down in the evening, and on the succeeding morning half a pint is poured upon fourteen gallons of new milk, which is thus effectually coagulated, and in consequence produces a delicious cheese.
This is a method for coagulating milk without animal rennet, and it is written for a dairy working at farm scale. As given it cannot be followed safely: the milk is never heated, the coagulant is of unmeasured strength, and nothing in the text controls acidity or aging.
- Raw milk, never heated"New milk" means milk fresh from the cow, still at body heat, and nothing here brings it above that. Cheese made this way relies on the herd, the dairy and the ripening cellar to keep Listeria monocytogenes, E. coli O157:H7, Salmonella and Campylobacter in check, and this text specifies none of those controls. A current, tested cheesemaking recipe should be used instead.
- No measured coagulant strength"A strong infusion" of flowers is not a quantity. Plant coagulants vary enormously in enzyme activity with species, season, flower maturity and steeping time, so the half-pint dose to fourteen gallons may set the milk firmly, weakly, or not at all. A curd that sets slowly at ambient temperature is a curd that sours and spoils on the way.
- No acidification or aging instructionsSafe cheese depends on a starter culture dropping the pH within a known window, then on salting and a defined ripening period. The entry stops at "effectually coagulated" and says nothing about any of it.
- The scaleFourteen imperial gallons is roughly 64 litres, about 17 US gallons — a farm dairy's morning milking, not a kitchen batch. Half an imperial pint is about 10 fl oz.
- Yellow ladies' bedstrawGalium verum, long known in English as cheese rennet or curdwort. It is traditionally credited with curdling milk, though its clotting activity is weak and poorly documented, and it grows alongside several near-identical Galium species. The plant was also used as a yellow dye, which may be part of why it turns up in cheese lore.
- "Eardown"Possibly the cardoon, Cynara cardunculus, whose dried flowers are the classic vegetable coagulant of Iberia, though the word is not standard and the identification is a guess. Cardoon proteases are strongly proteolytic and give a soft, spreadable, faintly bitter curd quite unlike a calf-rennet cheese.
Rennet was the awkward ingredient of the pre-industrial dairy: it meant a dried calf's stomach, its strength unknown until it was used, and it went bad. Standardised liquid rennet only became a commercial product in the later nineteenth century, and entries like this one preserve the older workarounds. Plant coagulants are genuinely ancient — the cardoon-set cheeses of Portugal and Extremadura, such as Serra da Estrela and Torta del Casar, are still made with thistle flowers today, and their characteristic runny, slightly bitter paste is a direct result of it. Galium verum's English folk names, cheese rennet and curdwort, record a comparable use here, though the plant's clotting power is generally reckoned much weaker than the cardoon's, and how widely it was actually relied on rather than merely written about is hard to establish.