Uticaj lecitina različitog porekla na kristalizaciona svojstva masne faze i kvalitet mazivog krem proizvoda sa dodatkom funkcionalnih biljnih ulja

Abstract

Konditorska industrija Srbije za proizvodnju mazivog krem proizvoda isključivo koristi sojin lecitin. Veliki obim proizvodnje ulja iz semena suncokreta i uljane repice u Srbiji uticao je na proizvodnju suncokretovog i repičinog lecitina, kao nusproizvoda postupka degumiranja u fazi rafinacije ovih ulja. Masna faza mazivog krem proizvoda sadrži biljne masti dobijene metodama hidrogenacije, koje kao nusprodukte imaju visok udeo nepoželjnih trans-masnih kiselina. U cilju poboljšanja mazivosti ovog proizvoda dodaje se i rafinisano suncokretovo ulje, koje sadrži veliki udeo linolne esencijalne masne kiseline, kao i α-tokoferol (E vitamin), ima prosečan sadržaj sterola, nizak sadržaj skvalena i karotenoida, ali gotovo da ne sadrži esencijalnu α-linolensku masnu kiselinu i antioksidante δ- i γ-tokoferol. U prvoj fazi doktorske teze ispitana je mogudnost zamene sojinog lecitina u proizvodnji mazivog kakao-krem proizvoda sa suncokretovim i repičinim lecitinom u smislu optimizacije koncentracije dodatog lecitina i vremena mlevenja u laboratorijskom kugličnom mlinu. U drugoj fazi ispitana je mogudnost poboljšanja nutritivne vrednosti mazivog kakao-krem proizvoda zamenom dela i celokupne količine suncokretovog ulja funkcionalnim uljima iz semena soje, uljane repice i susama. Gasnom hromatografijom ispitan je sastav masnih kiselina u masti, biljnim uljima i lecitinima različitog porekla, gde je u lecitinima određen i sastav fosfolipida primenom kvantitativne fosforne nuklearno-magnetno-rezonantne tehnike. Kristalizacione osobine masne faze mazivog kakao-krem proizvoda ispitane su pulsnom nuklearno-magnetnom-rezonantnom spektroskopijom, dok je kinetika kristalizacije definisana primenom Gompertz-ovog matematičkog modela. Reološke karakteristike mazivog kakao-krem proizvoda ispitane su rotacionom viskozimetrijom, određene su teksturalne karakteristike proizvoda na teksturometru i toplotne osobine primenom diferencijalne skenirajude kalorimetrije. Boja proizvoda definisana je tristimulusnom kolorimetrijom, a senzorna analiza određena je metodom skale u vremenskom intervalu od šest meseci čuvanja uzorka na tamnom mestu i sobnoj temperaturi. Ispitivanje održivosti mazivog kakao-krem proizvoda obuhvatilo je određivanje nastalih aldehida, kao proizvoda oksidacije lipida, gasnom hromatografijom.

Soy lecithin is widely used emulsifier in confectionery industry of Serbia. On the other hand, there is a large production of sunflower and rapeseed oil, which contributed the production of sunflower and rapeseed lecithin as a by-product of degumming of crude oil during refining process. Another issue is a high level of undesirable trans-fatty acids in hydrogenated vegetable fats that are being used in the production of cream spread. Beside hidrogenated fats, cream product contains sunflower oil with essential fatty acids (oleic and linoleic) and α-tocopherol (E vitamin), has an average content of sterols, squalene and a low content of carotenoids, but almost does not contain the essential α-linolenic acid and antioxidants, δ-and γ-tocopherol. The first phase of this work investigates the possibility of soy lecithin replacement in cocoa spread cream production with sunflower and rapeseed lecithin, in terms of optimizing the amount of lecithin and milling time in laboratory ball mill. The second phase investigates nutrition value improvement of cocoa spread cream, with partly or completely replacing sunflower oil with functional soybean, rapeseed and sesame oil. Gas chromatography was used in order to examine the fatty acid composition in edible non trans-fat and vegetable oils, as well as in lecithin from different sources. Phospholipid composition in soy, sunflower and rapeseed lecithin was determined using quantitative phosphorus nuclear magnetic resonance technique. Crystallization properties of fat phase of cocoa spread cream were examined by pulsed nuclear magnetic resonance spectroscopy, while crystallization kinetics was defined using the Gompertz's mathematical model. Rheological properties of cocoa spread cream were analyzed by rotational viscosity, certain textural characteristics were determined using texture analyser and also thermal properties using differential scanning calorimetry. The color on the surface of cocoa spread cream was defined using tristimulus colorimetric method, and sensory analysis was determined by the scale over a period of six months of storage in the dark and room temperature. Shelf-life of cocoa spread cream was determined applying gas chromatographic analyses of the formed aldehydes as secondary products of lipid oxidation.