Piimhappebakterite lisamise ja pastöriseerimise mõju kombuchale
Laen...
Kuupäev
2025
Kättesaadavus
04.09.2025
Autorid
Ajakirja pealkiri
Ajakirja ISSN
Köite pealkiri
Kirjastaja
Eesti Maaülikool
Abstrakt
Kombucha ehk teeseenejook on fermenteeritud jook, mille kvaliteeti mõjutavad mikroobikooslus ja tootmistingimused. Viimastel aastatel on kasvanud huvi piimhappebakterite (LAB) sihipärase lisamise vastu, kuid teadmised nende lisamise ajastusest ja kuumtöötlemise mõjust kombucha omadustele on piiratud.
Bakalaureusetöö eesmärk oli teaduskirjanduse ja eksperimentaalse töö põhjal hinnata, kuidas LABide lisamine mõjutab kombucha füüsikalis-keemilisi, mikrobioloogilisi ja sensoorseid näitajaid sõltuvalt lisamise ajast ja pastöriseerimisest.
Katsetöö teostati kahes etapis: LAB (Lactiplantibacillus plantarum TAK59) lisati kas 2. kääritamispäeval või pärast seitsmepäevast fermentatsiooni ja sellele järgnenud pastöriseerimist. Analüüsiti pH-d, tiitritavat happesust, lahustunud kuivainete sisaldust (Brix), värvusparameetreid, mikroorganismide arvukust ja viidi läbi sensoorne hindamine; valitud proovides määrati ka orgaanilised happed.
Tulemused näitasid, et LAB aitas säilitada äädikhappebakterite eluvõimet ja suurendas LABide arvukust, kuid ei tekitanud mõõdetavat piimhappe kogust. Sensoorne hinnang paranes LABi varajase lisamise korral, viidates potentsiaalile maitseprofiili optimeerimisel. Samas tõi LABi lisamine pärast pastöriseerimist kaasa soovimatu happesuse ja madalama meeldivushinnangu.
Töö tulemused toetavad LABide sihipärast rakendamist kombucha tootmises ning loovad aluse edasisteks uuringuteks starterkultuuride ja tootmisparameetrite optimeerimisel.
Kombucha is a fermented beverage, the quality of which is influenced by microbial composition and production parameters. In recent years, interest has increased in the targeted addition of lactic acid bacteria (LAB), yet knowledge regarding the timing of their application and the impact of thermal treatment on kombucha properties remains limited. The aim of this bachelor’s thesis was to evaluate, based on scientific literature and experimental work, how the addition of LAB affects the physicochemical, microbiological, and sensory characteristics of kombucha, depending on the timing of addition and pasteurization. The experimental study was conducted in two stages: Lactiplantibacillus plantarum TAK59 was added either on the second day of fermentation or after seven days of fermentation followed by pasteurization. Analyses included pH, titratable acidity, total soluble solids (Brix), color parameters, microbial counts, and sensory evaluation; organic acids were quantified in selected samples. The results showed that LAB supported the viability of acetic acid bacteria and increased LAB counts, yet no measurable lactic acid was detected. Sensory quality improved with early LAB addition, suggesting potential for flavor optimization. In contrast, LAB addition after pasteurization led to undesirable acidity and lower acceptability. The findings support the targeted use of LAB in kombucha production and provide a basis for further studies on starter culture application and process optimization.
Kombucha is a fermented beverage, the quality of which is influenced by microbial composition and production parameters. In recent years, interest has increased in the targeted addition of lactic acid bacteria (LAB), yet knowledge regarding the timing of their application and the impact of thermal treatment on kombucha properties remains limited. The aim of this bachelor’s thesis was to evaluate, based on scientific literature and experimental work, how the addition of LAB affects the physicochemical, microbiological, and sensory characteristics of kombucha, depending on the timing of addition and pasteurization. The experimental study was conducted in two stages: Lactiplantibacillus plantarum TAK59 was added either on the second day of fermentation or after seven days of fermentation followed by pasteurization. Analyses included pH, titratable acidity, total soluble solids (Brix), color parameters, microbial counts, and sensory evaluation; organic acids were quantified in selected samples. The results showed that LAB supported the viability of acetic acid bacteria and increased LAB counts, yet no measurable lactic acid was detected. Sensory quality improved with early LAB addition, suggesting potential for flavor optimization. In contrast, LAB addition after pasteurization led to undesirable acidity and lower acceptability. The findings support the targeted use of LAB in kombucha production and provide a basis for further studies on starter culture application and process optimization.
Kirjeldus
Bakalaureusetöö
Toiduteaduse ja toiduainete tehnoloogia õppekaval
Märksõnad
bakalaureusetööd, funktsionaalsed joogid, teeseenejook, fermentatsioon, SCOBY, sensoorne hindamine