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Cilj ovog diplomskog rada bio je ispitati utjecaj zamjene dijela pšeničnog brašna s brašnom specijalnih tipova ječmenog slada (u udjelima 20, 40 i 60 %), ali i utjecaj smanjene količine dodane saharoze (83,3 %, 66,6 % i 50,0 % u odnosu na standardnu recepturu) na kvalitetu biskvita. Sladno brašno dobiveno je mljevenjem specijalnih tipova pivarskog ječmenog slada: Pilsner, Amber i prženi Black slad. U uzorcima laboratorijski proizvedenih biskvita određen je sadržaj vlage, aktivitet vode, specifični volumen, teksturalni profil i boja te je provedena senzorska ocjena uzoraka. Na temelju dobivenih rezultata može se zaključiti da smanjenje dodatka saharoze uzrokuje značajno povećanje udjela i aktiviteta vode, ali se može primijetiti da je to povećanje manje u uzorcima s dodatkom sladnog brašna. Specifični volumen se smanjuje uslijed smanjenog dodatka šećera, a sladno brašno nema značajan utjecaj na specifični volumen u odnosu na uzorke sa pšeničnim brašnom. Uslijed smanjenog specifičnog volumena značajno se povećava čvrstoća i otpor žvakanja, a smanjuje kohezivnost i elastičnost biskvita proporcionalno sa smanjenjem količine dodane saharoze i povećanjem udjela sladnog brašna u recepturi. Svjetlina uzoraka opada, a udio crvene i žute kromatske komponente se povečava proporcionalno dodatku Pilsner i Amber sladnog brašna dok prženi slad Black daje biskvite izrazito tamne, gotovo crne boje. Smanjenje količine dodane saharoze i zamjena pšeničnog brašna s Pilsner i Amber sladnim brašnom do 60 % nema negativan utjecaj na senzorska svojstva biskvita. The aim of this study was to investigate the effect of replacing the part of wheat flour with malted brewer’s barley flour (20, 40 and 60 %), as well as the effect of reduced sucrose addition (83.3%, 66.6% and 50.0%) on the quality of sponge cakes. Moisture, water activity, and specific volume of samples were evaluated. The texture profile analysis, colour determination and sensory evaluation was also conducted. Based on the results of the research carried out it can be concluded that reduced sucrose addition significantly increases the moisture content and water activity in sponge cakes, but it can still be observed that this increase is less in the samples with the addition of malted flour. The specific volume decreases due to the reduced addition of sugar, and malt flour has no significant effect on the specific volume compared to the samples with wheat flour. Due to the reduced specific volume, the hardness and chewiness are significantly increased, and the cohesiveness and elasticity of the samples is reduced proportionally to the decrease in the amount of added sucrose and the increase of malted flour in the recipe. The lightness of the samples decreases, and the proportion of red and yellow chromatic components increases with the addition of Pilsner and Amber malted flour. The roasted malt causes a distinctly dark, almost black colour of the sponge cake. Reducing the amount of added sucrose and replacing wheat flour with Pilsner and Amber malt flour by up to 60% has no negative impact on the sensory properties of the sponge cakes. |
