Usage of multiple emulsions to design low fat ice cream


Tezin Türü: Yüksek Lisans

Tezin Yürütüldüğü Kurum: Orta Doğu Teknik Üniversitesi, Mühendislik Fakültesi, Gıda Mühendisliği Bölümü, Türkiye

Tezin Onay Tarihi: 2016

Öğrenci: EZGİ TEKİN

Danışman: SERPİL ŞAHİN

Özet:

The primary objective of this thesis was to design similarly perceived low fat ice cream with regular fat ice cream by using multiple emulsions. Thus, it was aimed to prepare multiple emulsion formulations by using food grade stabilizers and emulsifiers and to reduce the amount of fat in ice cream considerably. With the use of polyglyserol poliricinoleate (PGPR) and PGPR-lecithin blend as emulsifier in the primary phase and different gums such as guar gum (GG), locust bean gum (LBG) and gum tragacanth (GT) and their blends as stabilizer in the secondary phase, the most stable multiple emulsions were formed. There was no difference between multiple emulsions prepared with PGPR-lecithin blend and only PGPR in terms of particle size, rheological properties and stability. Different gum formulations affected the emulsion characteristics in different way. Guar gum (1%) and GG-GT (0.75%-0.25%) were chosen since they provided good emulsions with acceptable particle size, apparent viscosities and stability values. Ice cream samples prepared accordingly and PGPR-lecithin and GG-GT blends had higher overrun values, better meltdown resistance and higher overall acceptability in sensory analysis. Reduced fat and regular fat containing ice cream prepared with conventional method were compared with ice cream prepared with multiple emulsion method in terms of rheological properties, overrun, melt-down resistance and sensory properties. Reduction of fat to 2.82% by means of double emulsion was possible without affecting ice cream quality adversely.