Author/Editor		Fidler, Nataša
Title		Tehnološki in kakovostni parametri dietetskih marmelad
Translated title		Technological and quality parameters of dietetic marmalades
Type		monografija
Place		Ljubljana
Publisher		Biotehniška fakulteta, Oddelek za živilsko tehnologijo
Publication year		1993
Volume		str. 50
Language		slo
Abstract		The aim of the work was to investigate the influence of different sweeteners (sucrose and Natreen) on chemical, micro biological, sensorial and dietetic properties of grapefruit and orange marmalades. Suitable recipes were developed on the basis of degustation. A mixture of caragenan and algal was used as a gelling agent. The relation between glucose, fructose and sucrose in the marmalade made with Natreen was the same as in the mixture of row materials (1:1:1), however in marmalades made with sugar it was altered, due to a sucrose surplus. Marmalades made with Natreen contain less dry matter and more water, which results in higher water activity. The amount of total acids, defined as citric acid, is higher in marmalades with Natreen, which causes lower pH value. Due to higher ratio of fruit, colors, smell and taste are better preserved in marmalades made with Natreen. Replacing the sucrose with Natreen lowers the energy value by 55% for orange marmalades and 65% for grapefruit marmalades. Marmalades with Natreen contain more vitamins, minerals and water, similar amount of proteins and dietary fibre and far less mono- and disaharides. Marmalades made with sugar and those made with Natreen are micro biologically stable. The results of panel analyses show that there are no statistically significant differences between tastes of marmalades with different sweeteners. In laboratory analyses marmalades made with Natreen resulted in better grades that marmalades made with sugar.
Summary		V nalogi smo raziskovali vpliv različnih sladil (saharoze in Natrena) na kemične, mikrobiološke, senzorične in prehranske lastnosti marmelad iz grenivk in pomaranč. Na osnovi degustacij smo sestavili ustrezne recepture. Kot sredstvo za želiranje smo uporabili zmes karagenana in algala. Razmerje med glukozo, fruktozo je pri marmeladah z Natrenom enako, kot je bilo v zmesi osnovnih surovin (1:1:1), medtem ko je pri marmeladi z dodanim sladkorjem porušeno v prid saharoze. Marmelade z Natrenom vsebujejo manj suhe snovi in več vode, kar ima za posledico večjo aktivnost vode. Količina skupnih kislin, izraženih kot citronska, je večja pri marmeladah z Natrenom, kar pogojuje nižjo pH-vrednost. Zaradi večjega deleža sadja imajo marmelade z Natrenom bolje ohranjeno barvo, vonj in okus po sadju. Zamenjava saharoze z Natrenom zniža energijsko vrednost marmelad za 55% pri pomarančnih ter 65% pri marmeladah iz grenivk. Marmelade z Natrenom vsebujejo več vitaminov, mineralov in vode, podoben delež beljakovin in prehranskih vlaknin ter bistveno manj mono- in disaharidov. Tako marmelade s sladkorjem kot marmelade z Natrenom so mikrobiološko stabilne. Rezultati potrošniške analize kažejo, da v okusu marmelad z različnim sladilom ni statistično signifikantnih razlik. Pri laboratorijski analizi so bile marmelade z Natrenom ocenjene z večjim skupnim številom točk kot marmelade s sladkorjem.
Descriptors		FRUIT FOOD PRESERVATION FOOD ANALYSIS SWEETENING AGENTS FOOD MICROBIOLOGY NUTRITIVE VALUE