Fermentacija i antimikrobna aktivnost kombucha crnog, zelenog, bijelog i voćnog čaja

undergraduate thesis

• Title (english): Kombucha tea fermentation and its antimicrobial activity
• Author: Lidia Moharić
• Mentor: Sunčica Beluhan (mentor)
• Granter: University of Zagreb; Faculty of Food Technology and Biotechnology; (Department of Biochemical Engineering); (Laboratory for Biochemical Engineering, Industrial Microbiology and Malting and Brewing Technology); Zagreb
• Defense date and country: 2015-09-10, Croatia
• Scientific / art field, discipline and subdiscipline: BIOTECHNICAL SCIENCES; Biotechnology; Engineering

Abstract

Kombucha je odavno poznati osvježavajući napitak dobiven fermentacijom čaja, uz dodatak šećera i simbiotički združene kulture bakterija octene kiseline i kvasaca. Ovaj se napitak stoljećima intenzivno konzumira diljem cijelog svijeta zbog svojih profilaktičkih i terapeutskih svojstava. U ovom su radu pripremljene infuzije crnog, zelenog, bijelog i voćnog čaja (5 g/L), zaslađene sa 70 g/L saharoze, te fermentirane pomoću kombuche tijekom 35 dana pri
28°C. Uočeno je da su promjene pH vrijednosti bile povezane sa simbiotskim metaboličkim aktivnostima kvasaca i bakterija octene kiseline. Debljina i prinos bakterijske celuloze povećala se tijekom fermentacije. Uočena je antimikrobna aktivnost kombuche na Gram-pozitivne i Gram-negativne bakterije (Streptococcus aureus, Escherichia coli i Salmonella typhimurium), no ne i na kvasac Candida albicans.

Abstract (english)

Kombucha is a traditional refreshing beverage obtained by the fermentation of sugared tea with a powerful symbiosis of acetic bacteria and yeasts. This drink has been extensively consumed for a long time worldwide for its prophylactic and therapeutic properties. In this present study, the tea broths produced with black, green, white and fruit teas (5 g/L) were fermented naturally at 28°C with kombucha over a period of up to 35 days in the presence of 70 g/L sucrose. Changes in pH were related to the symbiotic metabolic activities of yeasts and acetic acid bacteria. The thickness and yield of bacterial cellulose increased with fermentation time. Antimicrobial activities were observed in the fermented samples against the tested Gram-positive and Gram-negative organisms (Streptococcus aureus, Escherichia coli and Salmonella typhimurium), but Candida albicans was not inhibited by kombucha.

• Keywords: fermentirani čaj; kombucha; antimikrobna aktivnost
• Keywords (english): fermented tea; kombucha; antimicrobial activity
• Language: croatian
• URN:NBN: urn:nbn:hr:159:623477
• Study programme: Title: Biotechnology; Study programme type: university; Study level: undergraduate; Academic / professional title: sveučilišni/a prvostupnik/prvostupnica (baccalaureus/baccalaurea) inženjer/inženjerka biotehnologije (sveučilišni/a prvostupnik/prvostupnica (baccalaureus/baccalaurea) inženjer/inženjerka biotehnologije)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2015-12-16 09:54:46