Opis postupka vođenja i karakteristika kiselog tijesta za proizvodnju trajnijih pekarskih proizvoda

master's thesis

• Title (english): Description of the leading procedure and characteristics of sourdough for the production of bakery products with a longer shelf life
• Author: Helena Kantoci
• Mentor: Jasna Mrvčić (mentor)
• Committee member: Damir Stanzer (predsjednik povjerenstva)
• Committee member: Snježana Kazazić (član povjerenstva)
• Committee member: Andreja Leboš-Pavunc (član povjerenstva)
• Granter: University of Zagreb; Faculty of Food Technology and Biotechnology; (Department of Food Engineering); (Laboratory for Fermentation and Yeast Technology); Zagreb
• Defense date and country: 2023-12-18, Croatia
• Scientific / art field, discipline and subdiscipline: BIOTECHNICAL SCIENCES; Biotechnology

Abstract

Smatra se da je uvođenje kiselog tijesta u proizvodnju kruha odlučujući korak za postizanje njegove više kvalitete, a onda i širenje upotrebe kiselog tijesta na tržištu. Cilj ovog rada bio je opisati postupak vođenja kiselog tijesta pomoću komercijalno dostupne starter kulture i ispitati trajnost kruha proizvedenog njenom primjenom. Kiselim tijestima određivana je pH vrijednost, ukupna titracijska kiselost (TTA) te koncentracija odabranih metabolita UPLC metodom. Broj mikrobnih stanica određivan je nacjepljivanjem na hranjivi agar, dok je antifungalna aktivnost kiselog tijesta određivana disk difuzijskom metodom. Na osnovu spektrometrije masa dokazano je da kultura sadrži bakteriju Lactiplantibacillus plantarum i kvasac Saccharomyces cerevisiae. Postupkom vođenja kiselog tijesta kojim se zadržava 10 % kiselog tijesta kao inokuluma za slijedeću fermentaciju može se održati starter kulturu aktivnom kroz 14 dana prihranjivanja, a kruščići pripremljeni s dodatkom kiselog tijesta u iznosu od 15 % odnosno 30 % na brašno, imali su manje zone kontaminacije u odnosu na kruščiće proizvedene bez kiselog tijesta. Tako se dodatak kiselog tijesta pokazao kao učinkovita prirodna zaštita za inhibiciju rasta plijesni Penicillium sp. s obzirom na sposobnost Lpb. plantarum da sintetizira široki spektar spojeva s antifungalnim djelovanjem.

Abstract (english)

It is considered that the introduction of sourdough in the production of bread is a decisive step for achieving its higher quality, and then the expansion of the use of sourdough on the market. The aim of this work was to describe the process of leading sourdough using a commercially available starter culture and to examine the durability of bread produced using it. The pH value, total titration acidity (TTA) and the concentration of selected metabolites were determined in sourdough samples using the UPLC method. The number of microbial cells was determined by inoculation on nutrient agar, while the antifungal activity of the sourdough was determined by the disc diffusion method. Based on mass spectrometry, it was proved that the culture contains the bacterium Lactiplantibacillus plantarum and the yeast Saccharomyces cerevisiae. The sourdough leading procedure, which retains 10 % of the sourdough as an inoculum for the next fermentation, can keep the starter culture active through 14 days of feeding, and the bread roll prepared with the addition of sourdough in the amount of 15 % or 30 % to the flour had smaller contamination zones compared to the bread roll produced without sourdough. In this way, the addition of sourdough proved to be an effective natural protection for inhibiting the growth of Penicillium sp. considering the ability of Lpb. plantarum to synthesize a wide spectrum of compounds with antifungal activity.

• Keywords: starter kultura; kiselo tijesto; bakterije mliječne kiseline; fermentacija; antifungalna aktivnost
• Keywords (english): starter culture; sourdough; lactic acid bacteria; fermentation; antifungal activity
• Language: croatian
• URN:NBN: urn:nbn:hr:159:292275
• Study programme: Title: Bioprocess Engineering; Study programme type: university; Study level: graduate; Academic / professional title: magistar/magistra inženjer/inženjerka bioprocesnog inženjerstva (magistar/magistra inženjer/inženjerka bioprocesnog inženjerstva)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2024-05-14 08:18:20