20.500.12556/RUL-130545 Tehnologije dekofeinizacije kave Coffee decaffeination technologies Kava je priljubljen napitek, ki ga uživajo mnogi. Med izdelke iz kave spada tudi brezkofeinska kava, ki je proizvedena z različnimi postopki. Odstranjevanje kofeina izvedejo na zeleni kavi pred praženjem. Proizvajalci kave brez kofeina so posebej pozorni na ohranjanje optimalnih senzoričnih lastnosti, saj prihaja med postopki odstranjevanja kofeina v kavi do različnih sprememb barve, arome in sestave. Kava je bogat vir kofeina, saj lahko ta predstavlja do 3 % suhe mase, zato je učinkovito odstranjevanje tega alkaloida kompleksen večfazen proces. Najpomembnejši korak, pred vsemi uveljavljenimi postopki dekofeinizacije, je uvajanje pare oz. namakanje zelene kave z namenom nabrekanja zrnja. Poznamo klasične metode, kjer za ekstrakcijo kofeina uporabljamo organska topila, kot sta etilacetat in diklorometan. Dekofeinizacija z organskimi topili lahko poteka po direktni ali indirektni metodi. Pri uporabi organskih topil je pomembno, da v končnem izdelku ni ostankov toksičnih topil. Razvitih je več metod za dekofeinizacijo z vodo, pri katerih se poleg kofeina ekstrahirajo tudi druge vodotopne komponente kave, ki jih je potrebno v zaključnih fazah postopka vrniti v kavo. Najbolj napredna metoda, ki tudi najmanj spremeni sestavo kave, je ekstrakcija kofeina s superkritičnim CO2. Glavna omejitev te metode je visoka cena. V razvoju so postopki dekofeinizacije z biološkimi metodami, pri katerih je pomembna omejitev občutljivost mikroorganizmov in encimov na različne dejavnike. Za tovrstno dekofeinizacijo so primerni le določeni mikroorganizmi, za katere kofein ni toksičen. Coffee is a popular beverage enjoyed by many. Coffee products include decaffeinated coffee, which is produced by various processes. In practice, the caffeine is removed from the green coffee before roasting. Manufacturers of decaffeinated coffee take special care to maintain optimal sensory properties, as various changes in color, aroma, and composition occur when coffee is decaffeinated. Coffee is a rich source of caffeine, which can make up as much as 3% of the dry weight, so effectively removing this alkaloid is a complex multi-step process. The most important step before any established method of decaffeination is the introduction of steam or steeping green coffee for the purpose of swelling the beans. We are familiar with the classic methods that use organic solvents such as ethyl acetate and dichloromethane for caffeine extraction. Decaffeination with organic solvents can be carried out in a direct or indirect way. When organic solvents are used, it is important that no toxic solvent residues are present in the final product. Several methods of decaffeination with water have also been developed, in which other water-soluble components of coffee are extracted in addition to caffeine, which must be returned to the coffee in the final steps of the process. The most advanced method, which changes the composition of the coffee the least, is the extraction of caffeine with supercritical CO2. The major limitation of this method is its high cost. Decaffeination processes using biological methods are also under development, although the sensitivity of microorganisms and enzymes to various factors is a significant limitation. For this type of decaffeination process only a few microorganisms, which must tolerate caffeine, are appropriate. kava kofein dekofeinizacija senzorične lastnosti topnost ekstrakcija coffee caffeine decaffeination sensory properties solubility extraction true false false [S. Vesel] Slovenski jezik Angleški jezik Diplomsko delo/naloga 2021-09-16 08:15:02 2021-09-16 08:15:04 2022-09-09 04:16:56 0000-00-00 00:00:00 2021 0 Ljubljana 0 0000-00-00 NiDoloceno NiDoloceno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 663.933.8 196667 76328195 19615.pdf 19615.pdf 1 8A89CF460BFC1BEF43A0DCB0B036A326 3c3a522b6ea2a2640c1aefd917271a868615e2b864d4ec067f4e135e502212ab 2c8adb70-16b5-11ec-a523-00155dcfd717 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=147672 Biotehniška fakulteta 0 0 0