The red cabbage (purple-leaved varieties of ''
Brassica oleracea
''Brassica oleracea'' is a plant species from family Brassicaceae that includes many common cultivars used as vegetables, such as cabbage, broccoli, cauliflower, kale, Brussels sprouts, collard greens, Savoy cabbage, kohlrabi, and gai lan. ...
'' Capitata
Group) is a kind of
cabbage, also known as Blaukraut after preparation. Its leaves are colored dark red/purple. However, the plant changes its color according to the
pH value of the soil due to a
pigment
A pigment is a colored material that is completely or nearly insoluble in water. In contrast, dyes are typically soluble, at least at some stage in their use. Generally dyes are often organic compounds whereas pigments are often inorganic comp ...
belonging to
anthocyanin
Anthocyanins (), also called anthocyans, are water-soluble vacuolar pigments that, depending on their pH, may appear red, purple, blue, or black. In 1835, the German pharmacist Ludwig Clamor Marquart gave the name Anthokyan to a chemical co ...
s. In acidic soils, the leaves grow more reddish; in neutral soils, they will grow more purple, while an alkaline soil will produce rather greenish-yellow colored cabbages. This explains the fact that the same plant is known by different colors in various regions. It can be found in all of Europe, throughout the Americas, in China, and especially in Africa.
The juice of red cabbage can be used as a homemade
pH indicator
A pH indicator is a halochromic chemical compound added in small amounts to a solution so the pH (acidity or basicity) of the solution can be determined visually or spectroscopically by changes in absorption and/or emission properties. Hen ...
, turning red in acid and green/yellow in basic solutions. When cooking, red cabbage will normally turn blue; adding vinegar or acidic fruit to the pot is necessary to retain the cabbage's red color.
Red cabbage needs well-fertilized soil and sufficient humidity to grow. It is a seasonal plant that is seeded in spring and harvested in late autumn. Red cabbage is a better keeper than its "white" relatives and does not need to be converted to
sauerkraut
Sauerkraut (; , "sour cabbage") is finely cut raw cabbage that has been fermented by various lactic acid bacteria. It has a long shelf life and a distinctive sour flavor, both of which result from the lactic acid formed when the bacteria fe ...
to last the winter.
Uses
Red cabbage is often used raw for salads and
coleslaw
Coleslaw (from the Dutch term ''koolsla'' meaning 'cabbage salad'), also known as cole slaw, or simply as slaw, is a side dish consisting primarily of finely shredded raw cabbage with a salad dressing or condiment, commonly either vinaigrette ...
. This vegetable can be eaten cooked. It is the traditional accompanying side dish paired with many German meals, notably meat dishes like
Sauerbraten
Sauerbraten is a traditional German roast of heavily marinated meat. It is regarded as a national dish of Germany, and is frequently served in German-style restaurants internationally. It can be prepared from a variety of meats, most often from ...
or
Döner. At Christmas, it can be spiced, braised, and served as an accompaniment to seasonal roast goose or turkey. Often apples are added to give it a sweet-sour taste.
Cultivation
It is recommended to start red cabbage seeds indoors four weeks before the last frost. Sow in containers that allow for the movement of water through the bottom of a cell. Popular seedling starting containers are peat pots, egg cartons, plug trays, or milk cartons. Once the seedlings grow to about tall and have developed their first leaves, they can be hardened off and moved outside for transplanting. Red cabbage prefers climates that remain moist and cool for most of its vegetative growth stage, so it can be placed in the ground shortly after the last frost while the spring is still cool. The cabbage plants can be spaced about from one another. They will need watering often but are otherwise low-maintenance plants.
pH indicator
Red cabbage contains an
anthocyanin
Anthocyanins (), also called anthocyans, are water-soluble vacuolar pigments that, depending on their pH, may appear red, purple, blue, or black. In 1835, the German pharmacist Ludwig Clamor Marquart gave the name Anthokyan to a chemical co ...
-based dye that can be used as a
pH indicator
A pH indicator is a halochromic chemical compound added in small amounts to a solution so the pH (acidity or basicity) of the solution can be determined visually or spectroscopically by changes in absorption and/or emission properties. Hen ...
. It is red, pink, or magenta in acids (
pH < 7), purple in neutral solutions (pH ≈7), and ranges from blue to green to yellow in alkaline solutions (pH > 7).
Nutrition
Cooked red cabbage is 91% water, 7%
carbohydrate
In organic chemistry, a carbohydrate () is a biomolecule consisting of carbon (C), hydrogen (H) and oxygen (O) atoms, usually with a hydrogen–oxygen atom ratio of 2:1 (as in water) and thus with the empirical formula (where ''m'' may or ...
s, 1%
protein
Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residues. Proteins perform a vast array of functions within organisms, including catalysing metabolic reactions, DNA replication, respon ...
, and contains negligible
fat (table). It has a high content of
vitamin C
Vitamin C (also known as ascorbic acid and ascorbate) is a water-soluble vitamin found in citrus and other fruits and vegetables, also sold as a dietary supplement and as a topical 'serum' ingredient to treat melasma (dark pigment spots) a ...
and
vitamin K
Vitamin K refers to structurally similar, fat-soluble vitamers found in foods and marketed as dietary supplements. The human body requires vitamin K for post-synthesis modification of certain proteins that are required for blood coagulat ...
, containing 44% and 72%, respectively, of the
Daily Value
The Reference Daily Intake (RDI) used in nutrition labeling on food and dietary supplement products in the U.S. and Canada is the daily intake level of a nutrient that is considered to be sufficient to meet the requirements of 97–98% of health ...
(DV) per 100-gram amount, and is a moderate source of
vitamin B6
Vitamin B6 is one of the B vitamins, and thus an essential nutrient. The term refers to a group of six chemically similar compounds, i.e., "vitamers", which can be interconverted in biological systems. Its active form, pyridoxal 5′-phosphat ...
(17% DV) (table).
Phytochemicals
Red cabbage
phytochemical
Phytochemicals are chemical compounds produced by plants, generally to help them resist fungi, bacteria and plant virus infections, and also consumption by insects and other animals. The name comes . Some phytochemicals have been used as poison ...
s include
sulforaphane and other
glucosinolate
Glucosinolates are natural components of many pungent plants such as mustard, cabbage, and horseradish. The pungency of those plants is due to mustard oils produced from glucosinolates when the plant material is chewed, cut, or otherwise damage ...
s.
References
External links
How to Make Red Cabbage pH Indicator
{{Authority control
Cabbage
Leaf vegetables