Effect of the preparation conditions on the rheological and textural properties of monoglyceride oleogels

ANABELLA GIACOMOZZI; MARÍA ELENA CARRÍN; CAMILA A. PALLA

Rosario

Congreso; World Congress on Oils and Fats and 31st ISF Lectureship Series 2015; 2015

ASAGA junto a ISF (International Society for Fats Research) y LA AOCS (Sección Latinoamericana de la American Oil Chemists´Society)

Diets high in trans and saturated fats have numerous negative implications on humans´ health. Around the world, measures are being taken to reduce their use in food preparation, compelling the scientific community to search for technological alternatives that allow the obtention of products with similar physical and organoleptic characteristics but healthier for consumers. Oleogels are among some of the most promising alternatives for replacing these types of fats. In this contribution, oleogels produced with Myverol (monostearin: 88.2%, monopalmitin: 3.6%) and different vegetable oils were studied in order to obtain products with similar behavior to margarines. This work is a preliminary study with the aim to evaluate the influence of several variables of gel preparation (type, speed, and time of agitation, Myverol concentration, type of oil - soybean, high oleic sunflower and sunflower-, preparation, and cooling temperature) on oil binding capacity (OBC), rheological and textural properties of obtained oleogels. Rheological characterization was carried out by dynamic oscillatory test on molten mixtures and oleogel cylindrical samples. Mechanical properties of oleogels were measured with texture profile analysis (TPA) test. OBC was determined by centrifugation.The obtained results show that the rheological properties were affected by the Myverol concentration as well as by the preparation and cooling temperatures. Oleogels obtained using magnetic stirrer shown elastic modulus (G´) and viscous modulus (G´´) higher than the ones obtained under high shear using a homogenizer. The gelation temperature was ranged between 31 and 35 ºC for all the samples, and the highest value was obtained in soybean oil oleogels. Regarding textural properties, both fracturability and hardness exhibited an increment when higher Myverol concentrations were used. However, a preparation temperature higher than 70 °C and a cooling temperature lower than ambient produce a decrease in textural parameters. OBC was greatly affected by Myverol concentration, cooling temperature and vegetable oil type; the high oleic sunflower oil showed the highest value (99.88%). On the other hand, the stirring time did not affect any of the studied oleogels properties.Based on the aforementioned results, an appropriate experimental design will be performed to select the suitable condition to prepare strong oleogels with rheological and textural properties similar to commercial margarine.