Herb growing 30-80 cm high in large parts of Europe, but also in the Near East and North America. Characteristic are the square stems and spiky, rolled leaves, which resemble needle tips, as well as small golden yellow flowers in panicles, later smooth, black fruits. Flowering time is from May to September.
The name refers to the ability, similar to the rennet ferment of the stomach - to curdle milk. Rennet was used for cheese making. Since "rennet ferment" contained in the sap of the plant, is a protease that coagulates milk with the polyphenols of the plant.
Phytotherapeutically, the dried aerial parts of the plant, the rennet - Galii veri herba, are used.