Cysteine
Cysteine is a sulphur-containing amino acid, like methionine. Cysteine is usually a non-essential amino acid, since it can be synthesized by the human body from methionine, so some requirements are expressed in terms of the sum of cysteine and methionine. However, it might be essential for some people (infants notably), which makes it a semi-essential proteinogenic amino acid. Among other uses, it is a food additive (E920) used for flavouring.
Abbreviations: Cys, C Formula: C3H7NO2S.Foods rich in cysteine (in quantity per 100 g)
- Spices, mustard seed (0.68 g)
- Seeds, hemp seed (0.67 g)
- Seaweed, spirulina (0.66 g)
- Leavening agents, yeast (0.50 g)
- Nuts, walnuts (0.46 g)
- Seeds, sunflower seed kernels (0.45 g)
- Oats (0.41 g)
- Seeds, chia seeds (0.41 g)
- Spices, fenugreek seed (0.37 g)
- Semolina, unenriched (0.36 g)
Foods rich in cysteine (relatively to energy)
- Seaweed, spirulina (2.28 mg/kcal)
- Carrots, raw (2.02 mg/kcal)
- Egg, whole (1.90 mg/kcal)
- Lupins, mature seeds (1.61 mg/kcal)
- Soybeans, mature cooked (1.56 mg/kcal)
- Asparagus, cooked (1.55 mg/kcal)
- Leavening agents, yeast (1.54 mg/kcal)
- Spinach, cooked (1.52 mg/kcal)
- Tofu, soft (1.49 mg/kcal)
- Spices, mustard seed (1.34 mg/kcal)
Foods rich in cysteine (relatively to target pattern)
- Dates, deglet noor (6.45)
- Carrots, raw (5.40)
- Semolina, unenriched (4.06)
- Nuts, chestnuts (3.80)
- Peppers, sweet (3.49)
- Bulgur, dry (3.19)
- Bread, pita (3.18)
- Wheat flour, white (3.03)
- Bread, wheat (2.99)
- Spelt, uncooked (2.97)