EFFECT OF STS SURFACTANT ON CANOLA- CARNAUBA WAX OLEOGEL AS A LOW SATURATED ACID SEMI-SOLID FAT FOR BAKERY SHORTENING SUBSTITUTION

Background and Aim: Shortening is a main ingredient of bakery products. Shortening’s thermo-rheological properties are related to the presence of high levels of saturated fatty acids content which makes crystalline structures. Consumption of high saturated acid fats increases the risk of coronary disease. Oleo-gelation is novel technique for physically changing liquid oils properties into semi-solid structure using low-digestible gelators. Carnauba is a food grade plant wax which can used for oleogel preparation. In this study, sorbitan tri Stearate (STS) was used to alter the structure of wax crystal structure and gels properties thereof.Methods: Carnauba wax was added to canola oil at 5, 8 and %11 concentrations, heated until complete desolvation. Then, STS was added at 0, 1 and %2. After complete mixing, samples were stored in refrigerator. Back extrusion texture analysis, DSC for heating and cooling cycles and solid fat content (NMR) were determined.Results: wax concentration increment raised the work of penetration into gels as well as average force during steady shear depth range while surfactant effect was not significant. All samples had two melting transitions near 20 and 75 °C. STS slightly shifted oleogels melting transitions to higher temperatures. In cooling cycle, one crystallization transition observed near 45 °C, so that STS at %2 concentration shifted the temperature to lower temperature for 8 °C. STS addition increased SFC at all temperatures as well as SFC reduction slope by temperature addition.Conclusion: Overall, STS changes intensity on carnauba wax crystal structure is not sufficient to reach the desired properties

Keywords:

Canola oil , Carnauba wax , DSC , Oleogel , STS