Senzorska svojstva keksa bez šećera i bezglutenskog kruha s dodatkom posija prosa i ksilanaze

master's thesis

• Title (english): Sensory properties of sugar-free biscuits and gluten-free bread with millet bran and xylanase
• Author: Iva Bogešić
• Mentor: Dubravka Novotni (mentor)
• Committee member: Nikolina Čukelj Mustač (predsjednik povjerenstva)
• Granter: University of Zagreb; Faculty of Food Technology and Biotechnology; (Department of Food Engineering); (Laboratory for Cereal Chemistry and Technology); Zagreb
• Defense date and country: 2020-07-16, Croatia
• Scientific / art field, discipline and subdiscipline: BIOTECHNICAL SCIENCES; Food Technology

Abstract

Proizvodi za posebne prehrambene potrebe, kao što su keksi i kruh za oboljele od dijabetesa i/ili celijakije, često imaju lošija senzorska svojstva u odnosu na konvencionalne proizvode. Kako bi takvi proizvodi istovremeno bili nutritivno vrijedni i senzorski prihvatljivi za potrošača, potrebno je provesti ispitivanje njihovih senzorskih svojstava. U ovom radu su ispitana senzorska svojstva keksa bez šećera i bezglutenskog kruha s dodatkom posija prosa i ksilanaze primjenom testova deskriptivne i hedonističke analize te nizanja po preferenciji. Proso je iznimno vrijedna žitarica čije se posije koriste za obogaćivanje hrane, jer ne sadrži gluten i djeluje hipoglikemijski. Najveći nedostatak posija prosa je to što daje proizvodu nepoželjan gorak okus i time smanjuje njegovu prihvatljivost. Enzim ksilanaza se koristi u pekarstvu jer poboljšava obradivost i stabilnost tijesta. Rezultati deskriptivne analize bezglutenskog kruha i keksa bez šećera pokazali su da su posije prosa uzrokovale pojavu tamnije boje, povećanje gorkog i naknadnog gorkog okusa te smanjenje tvrdoće. Nepoželjni gorki okus smanjen je kod uzoraka s ksilanazom tretiranim posijama prosa. Hedonistička analiza pokazala je porast prihvatljivosti kruha s dodatkom ksilanazom tretiranih posija prosa u odnosu na kruh s netretiranim posijama te je testom nizanja po preferenciji zauzeo prvo mjesto. Kod keksa bez šećera hedonističkom analizom i testom nizanja po preferenciji pokazalo se da najbolje ocijenjen sveukupni doživljaj ima kontrolni uzorak, a keks s dodanim posijama je bio u kategoriji 'neznatno mi se sviđa'.

Abstract (english)

Products for special dietary needs, such as biscuits and bread for people with diabetes and / or celiac disease, often have poorer sensory properties compared to conventional products. In order for such products to be both nutritionally valuable and sensory-acceptable to the consumer, it is necessary to conduct a test of their sensory properties. In this research, the sensory properties of sugar-free biscuits and gluten-free bread with the addition of millet bran and xylanase were tested using descriptive and hedonistic analysis and a sequencing by preference. Millet is an extremely valuable cereal whose bran is used to enrich food because it does not contain gluten and has a hypoglycemic effect. The biggest disadvantage of millet bran is that it gives the product an undesirable bitter taste and thus reduces its acceptability. The enzyme xylanase is used in baking because it improves the workability and stability of the dough. The results of a descriptive analysis of gluten-free bread and sugar-free biscuits showed that addition of millet bran caused a darker color of the product, increased bitter and subsequent bitter taste, and decreased hardness. Undesirable bitter taste was reduced in the sample with xylanase-treated millet bran. Hedonistic analysis shows an increase in the acceptability of bread with the addition of enzym treated millet bran compared to bread with untreated bran, and it took first place in the sequence test by preference. Hedonistic analysis and sequencing by preference of sugar-free biscuits showed that a control sample had the best rated overall experience, while the biscuit with bran was rated as 'slightly liked'.

• Keywords: bezglutenski kruh; keksi bez šećera; ksilanaza; posije prosa; senzorska svojstva
• Keywords (english): gluten-free bread; millet bran; sensory properties; sugar-free biscuits; xylanase
• Language: croatian
• URN:NBN: urn:nbn:hr:159:284206
• Study programme: Title: Food Safety Management; Study programme type: university; Study level: graduate; Academic / professional title: magistar/magistra inženjer/inženjerka upravljanja sigurnošću hrane (magistar/magistra inženjer/inženjerka upravljanja sigurnošću hrane)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2020-07-20 11:34:51