Nor Faadila M. Idrus’s research while affiliated with University of Science Malaysia and other places

Peanut (Arachis hypogaea) is an important source of protein and lipid globally. The effect of superheated-steam roasting on quality of peanut oil was evaluated based on physicochemical quality parameters. Three roasting temperatures (150, 200, and 250 °C) were used for different periods of roasting time and the obtained results were compared with those of conventional roasting. At 250 °C, superheated-steam roasted peanuts yielded more oil (26.84%) than conventionally roasted peanuts (24.85%). Compared with conventional roasting, superheated-steam roasting resulted in lower oil color, peroxide, p-anisidine, free fatty acid, conjugated diene and triene, and acid values and higher viscosity and iodine values in the roasted peanut oil. These values were significantly different from each other (p < 0.05). The fatty acids in roasted peanut oils were affected by roasting temperature and time for both the roasting modes. The superheated steam technique can be used to roast peanuts while maintaining their favorable characteristics.

Virgin coconut oil is a functional food which provides health benefits. It is different from other cooking oils in that it has medium-chain fatty acids rather than long-chain fatty acids. The traditional aqueous extraction of the oil is very flexible that can be applied in a medium to large-scale industry. The study was carried out to optimize the aqueous extraction of virgin coconut oil using response surface methodology. The most influencing three factors were used for this experiment, which are the coconut milk-to-water percentage, fermentation and refrigeration time. The optimization study showed that the method can produce the best yield with quality by using coconut milk (73.8%), fermented (14.1 h) and refrigerated time (20.5 h). Coconut milk percentage and fermentation time significantly affected the response of extraction yield (p ≤ 0.01). The aqueous extraction can be used commercially for the production of virgin coconut oil as the method is environmental friendly.

Colour, texture (hardness and fracturability) and microstructure were compared in peanuts (Arachis hypogaea) that were roasted by superheated steam oven (A-1500V, SHARP) in superheated steam mode and convection mode (normal without steam) operated at three different temperatures (250°C, 200°C and 150°C) for durations between 5 to 45 min. Different temperatures required different heating times for the roasting to be completed. Colour was expressed in terms of brightness (L*), whiteness (WI), redness (a*) and yellowness (b*) for each combination of roasting temperature and time. We found that L* and WI values decreased with increased roasting time and temperature, while a* and b* values increased when roasting time was extended. All the colour values (L*, a*, b*, WI) were more affected during superheated steam roasting than during convection roasting. Temperature increase by superheated steam was faster than in convection; however the roasting procedure was completed within a shorter time in convention. Hardness and fracturability, which represent the texture quality of peanuts after roasting, decreased with roasting time. This trend was, however, not statistically significant (p > 0.05). More oil was viewed to be extracted during superheated steam roasting than during convection roasting in scanning electron micrograph.