Proizvodnja kefirnog napitka uz dodatak suhih šljiva, grožđica i datulja

undergraduate thesis

• Title (english): Production of kefir beverage with addition of dried plums, raisins and dates
• Author: Marija Antunović
• Mentor: Mladen Pavlečić (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: 2022-09-19, Croatia
• Scientific / art field, discipline and subdiscipline: BIOTECHNICAL SCIENCES; Biotechnology

Abstract

Kefirni napitak je piće dobiveno fermentacijom vodene otopine saharoze s pomoću združene kulture kefirnih zrnaca sa ili bez dodatka sušenog voća. Mikroorganizmi koji su pretežito zastupljeni u kefirnim zrncima su bakterije mliječne kiseline, kvasci, bifidobakterije i bakterije octene kiseline. Kefirna zrnca korištena u ovom radu su iz kućnog uzgoja te im je mikrobiološki sastav nepoznat. Dodatkom sušenog voća u hranjivu podlogu osigurava se dodatan izvor nutrijenata, posebice ugljika i dušika, što djeluje pozitivno na rast i aktivnost mikroorganizama prisutnih u hranjivoj podlozi. U ovom završnom radu praćen je utjecaj i tijek proizvodnje kefirnog napitka uz dodatak tri vrste sušenog voća (šljive, grožđice, datulje). Rezultati istraživanja su pokazali da je najveći porast udjela suhe tvari, u odnosu na početni udio, ostvaren u eksperimentima gdje su u hranjivu podlogu dodane datulje. Najviši prinosi produkata poput etanola, manitola, mliječne i octene kiseline zabilježeni su kod kefirnog napitka gdje su dodane suhe šljive, a gdje je istovremeno zamijećen i najveći utrošak supstrata. Zaključno, u svim eksperimentima uočen je pozitivan učinak dodatka sušenog voća na proizvodnju kefirnog napitka

Abstract (english)

Kefir drink is a beverage obtained by fermentation of an aqueous solution of sucrose with the help of a combined culture of kefir grains with or without the addition of dried fruit. Microorganisms that are predominantly present in kefir grains are lactic acid bacteria, yeasts, bifidobacteria and acetic acid bacteria. The kefir grains used in this work are from domestic cultivation and their microbiological composition is unknown. The addition of dried fruit to the nutrient medium provides an additional source of nutrients, especially carbon and nitrogen, which has a positive effect on the growth and activity of microorganisms present in the nutrient medium. In this final paper, the influence and course of production of kefir drink with the addition of three types of dried fruit (plums, raisins, dates) was observed. The research results showed that the largest increase in the proportion of dry matter, compared to the initial proportion, was achieved in the experiments where dates were added to the nutrient medium. The highest yields of products such as ethanol, mannitol, lactic and acetic acid were observed in the kefir drink where prunes were added, and where the highest consumption of substrates was also observed. In conclusion, a positive effect of the addition of dried fruit on the production of kefir drink was observed
in all experiments.

• Keywords: keftirni napitak; kefirna zrnca; sušeno voće; suhe šljive; suhe grožđice; suhe datulje
• Keywords (english): kefir drink; kefir grains; dried fruit; dried plums; raisins; dried dates
• Language: croatian
• URN:NBN: urn:nbn:hr:159:365007
• 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: 2024-04-09 09:18:04