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Cold pressed and hexane extracted moringa seed oils (CPMSO and HEMSO) were evaluated for their physico-chemical and stability characteristics. The iodine value, saponification value and unsaponifiable matter of CPMSO and HEMSO were found to be 67.8 and 68.5 g I2 / 100 g oil, 190.4 and 191.2 mg KOH / g oil and 0.59 and 0.65%, respectively. The total tocopherols of CPMSO and HEMSO were found to be 95.5 and 90.2 mg/Kg. The fatty acid composition of CPMSO and HEMSO showed oleic acid as the major fatty acid (78-79%). The oxidative, thermal and frying stabilities of the CPMSO were compared with commercial raw and refined groundnut oil (GNO and RGNO). The CPMSO was of adequate thermal stability and better oxidative stability as it showed 79% lesser peroxide formation than GNO. The frying stability of CPMSO was better as it showed lower increase in free fatty acid (28%), peroxide value (10 meq O2/Kg) and color (25%) than RGNO (48%, 22 meq O2/kg and 52%, respectively) after frying.

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The kinetics of degradation of both green‐ and total‐colour of green chilli puree was studied at selected temperatures (50–90 °C). A fractional conversion concept was applied to determine the kinetic parameters. The degradation of green‐ and total‐colour followed first order reaction kinetics. In the case of green colour the data was based on changes in Hunter –a value while L × a × b was found to adequately represent total colour change. Dependence of the rate constant during heat treatment obeyed the Arrhenius relationship. The activation energy values for green‐ and total‐colour degradation were 23.04 and 25.02 kJ mol–1, respectively. These results indicated that total colour should be used as the quality indicator during thermal processing of green chilli puree. The pungency of green chilli puree decreased during thermal processing as the capsaicin content was reduced from 559 to 441 μg g–1 while the Scoville heat unit decreased from 8500 to 7480. The puree behaved as a shear‐thinning fluid and the flow activation energy at 100 r.p.m. equalled 19.22 kJ mol–1.

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The application of high intensity, pulsed infrared radiation for roasting of groundnuts is attempted and the product quality is compared with that of the conventionally roasted samples. Product qualities such as lightness (color), compressive strength (texture) and free fatty acid content are analyzed for different combinations of roasting duration (4-12 min) and temperature (160-200°C), selected based on central composite rotatable design (CCRD). Pulsed infrared roasting at 178-188°C for 6.8-9.2 min resulted in optimum product quality in terms of color, texture and free fatty acid content. The other parameters such as oil and moisture content, peroxide value and sensory characteristics of roasted nuts are also evaluated for the select temperature-duration combinations. The oil yield increased marginally with roasting duration and temperature. Peroxide number, an indicator of the stability of fat, did not vary during infrared roasting. Groundnuts processed at 180°C for 8 min scored high in terms of sensory attributes. Infrared roasting resulted in better product quality as compared to drum and sand roasting.

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