RESUMO
The process of jilebi making includes the frying of specially shaped batter strands to obtain a crisp texture followed by absorption of sugar syrup. The effects of frying temperature (150-180 °C) and time (15-300 s) on the physical characteristics have been investigated; these are moisture and fat contents, density, colour, textural attributes and microstructure. Among the textural parameters obtained by shearing the jilebi strands, shear failure force and the number of minor fractures increase markedly with an increase in time of frying. The brightness of the sample is lower when fried at higher temperatures like 180 °C compared to that of 150 °C; the hue or dominant wavelength of batter prior to frying is 578.0 nm, and after frying, it is between 564.8 and 591.3 nm indicating an overall shift towards yellow colouration during frying. The density of the jilebi strands decreases along with moisture content, while fat content increases gradually with an increase in frying time. The microstructure and image analysis of the fried products indicate the creation of porous structure consisting of several pores that are separated by thin cell walls of thickness between 10 and 15 µm. The eccentricity of pores/vacuoles in jilebi is between 0 and 0.92 indicating a close resemblance to elliptical shapes. The samples fried at 160 °C for 180-240 s have been judged as the best sample both as fried and fried-sugar syrup soaked products.
RESUMO
Demand for use of natural additives such as nutraceuticals, antioxidants, coloring and flavoring matter is continuously increasing world over. It is due to nutritional awareness among the masses and belief that most of the natural products are safe for human consumption. Interest has been shown recently on the use of natural antioxidants from oil seeds. Hence, oils obtained from sesame (Sesamum indicum) had been utilized for this purpose. Oils were thermally treated (T) to enhance the sesamol content from 4,900 to 9,500 ppm. A portion of resultant oil had been extracted with ethanol in a controlled conditions to yield a concentrate (ESSO-T) with sesamol content of 28,500 ppm. Whereas another portion after silica gel column separation yielded a concentrate (SSO-TFII) with sesamol content of 27,100 ppm. Refined sunflower oil without antioxidant was mixed with ESSO-T and SSO-TFII separately at the level of 2,000, 1,000, 500 and 200 ppm and its storage stability assessed was at ambient (22-28 degrees C) and elevated (37 degrees C) temperatures. Peroxide value (PV) and Free Fatty Acid content (FFA) of samples were estimated at intervals of 2 weeks for a total storage period of 12 weeks. Results indicated that ESSO-T at the level of 500 ppm had maximum protective effect on refined sunflower oil, where PV and FFA were found ranging between 2.1 to 5.9 and 0.10 to 0.15%; and 4.1 to 9.8 and 0.11 to 0.21% for samples stored at ambient and elevated conditions respectively. The storage stability of this sample was very close to the storage stability of sunflower oil containing TBHQ at 200 ppm. Comparatively in sunflower oil without antioxidant PV and FFA had gone up from 2.0 to 45.4 and 0.11 to 1.3% at ambient and 2.0 to 56.4 and 0.11 to 2.8% at elevated temperatures.