Sour cabbage (Serbian: kiseli kupus, Serbian Cyrillic: кисели купус; pronounced [kǐseli kǔpus]) A Serbian vegetable preserve similar to sauerkraut, with the difference that it is prepared through the lacto-fermentation of whole heads of cabbage (Brassica Oleracea var.capitata), not separate leaves or grated mass. No vinegar or boiling is required. In Serbia it's commonly home made conserve and many families in their cellars or other suitable places have big barrels (20 -200 l) that they every autumn fill with cabbages to make this traditional food.
The quality of the cabbage is the main factor in obtaining a good result and the requirements are somewhat higher and more specific in comparasion to sauerkraut. First of all, contrary to sauerkraut, the heads should be round or nearly round, or round, but, slightly flattened on the top. Since they are processed as whole, it's very important the pressure to be distributed uniformly on the entire surface. The core should be as small as possible, since it represents a waste and since its fermentation rate would differ from the leave's one (the fermentation must proceed uniformly everywhere). For the same reason, the ribs shouldn't be too much expressed; they should be firm, but, not hard and tough. The head should be firm and very compact. Its firmness shouldn't be owed to mechanical tissues, but to the compactness - the leaves should be packed very densely. The leaves themselves should be firm, but thick; their palisade mesophyll should be particularly well developed, not spongy mesophyll, nor epidermis. They should due their firmness to their structure, not to a high content of cellulose - its content shouldn't be high. They should be rich in sugar and dry content. At all levels there should be as little spaces as possible that could trap air. Such physical characteristics would permit the head to ferment and not to disintegrate, on one side, and on the another - to stay soft, but crispy, and not to become tough and paper-like, as well as to have a uniform fermentation. Obviously, the cabbage must also be healthy, clean and fresh.
The cabbage heads are salted (after the external leaves and core have been removed), packed into the barrel as densely as possible (another reason why round form is required) and covered with salted water (4-6% of salt). A heavy load (a rock, for example) is placed above, to keep them under the water, in anaerobic conditions. From time to time the water has to be reversed (flushed from the bottom of the barrel and than again sluiced onto the top), adding somewhat (but, always with salt) if necessary. A higher salinity makes the fermentation slower, while an insufficient salinity makes it unsafe. Higher temperatures require a higher salinity. The fermentation should be done at 16-22°C. The best temperature is 18-20°C. A cabbage fermented at a lower temperature has a better fragrance. The best known microorganisms involved in the process include Leuconostoc mesenteroides, Lactobacterium brevis, Streptococcus faecalis, Pediococcus cerevisiae and Lactobacterium plantarum.
The sour cabbage is very popular Serbian food, consumed mainly during the winter half of the year, both raw or cooked. As raw, it's a very popular winter salad, served usually dusted with pepper powder (aleva paprika) and/or black pepper (but, also just as is). In cooking it's used for sarma in the first place, but, for another dishes too.
Nutritional qualities are very similar to those of sauerkraut. The liquid (brine) from the barrel the sour cabbage has been fermented in, called rasol (or raso), is one of the best natural dietary supplements. It's traditionally used as a hangover remedy, but, its qualities far exceed that purpose. It's extremely rich in Vitamin C, but also in vitamins E, K, B complex as well as in very rare vitamin U. It's also rich in oligoelements (Ca, K, P, S, Fe, Cu, Zn, Mg), enzymes and lactic acid.
- Mihajlović, Ilija, ed. (7 November 2014). "KISELJENJE KUPUSA". AGRO INFO TEL. Agroinfotel. Retrieved 1 February 2015.
- Šumić, dr Zdravko; Dupalo, Predrag, eds. (10 November 2014). "Tehnologija proizvodnje kiselog kupusa". Tehnologija hrane/Enciklopedija. Tehnologija hrane. Retrieved 1 February 2015.
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