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Nigella sativa, commonly known as the black seed, is a culinary spice therapeutic against many ailments. Common preparation practice of roasting or heating the seeds often deteriorates bioactive compounds, which can be remedied with superheated steam (SHS). With roasting temperatures of 150, 200, and 250°C and roasting times of 10, 15, and 20 min, convection and SHS roasting media were tested, and their effects on proximate analysis, antioxidant assays, and oil quality were evaluated. For proximate content, moisture significantly decreased from 9.08% in unroasted seeds to 4.18%–1.04% in roasted seeds, while fat increased to as high as 44.76% from 32.87% in unroasted seeds. Roasting only slightly increased ash content and had no significant impact on protein and carbohydrate content. SHS roasted black seeds had better DPPH (2,2‐Diphenyl‐1‐picrylhydrazyl) radical scavenging capacity (RSC) than convection roasted seeds. DPPH RSC decreased with elevated roasting time and temperature, conversely related to total phenolic content, which increased with increased roasting time and temperature. Oil of roasted seeds developed an increasingly intense brown color from an initial light, yellow, unroasted oil with better extraction efficiency in SHS roasting. For oil quality analysis, free fatty acid values were significantly lower in both roasted samples. Peroxide value was initially recorded at 84 in convection and 48 (meq O2/kg of oil) in SHS roasted samples. In contrast, p‐anisidine values were initially recorded at 28.36 in convection roasted samples compared to 23.73 in SHS roasted samples. Based on all quality analyses, SHS showed better potential in black seed quality preservation. [ABSTRACT FROM AUTHOR]

Bilayer functional film made of poly(lactic acid), PLA incorporated with 2 wt.% marigold flower extract containing astaxanthin (PLA2M) was fabricated by using a blown-extrusion process. The release of astaxanthin, a keto-carotenoid antioxidant, from the PLA-based film towards 95% ethanol (ETOH) was investigated at 30 and 40 °C. PLA and PLA2M that had been in contact with 95% ETOH at 30 and 40 °C were also investigated for their optical, thermal, structural, molecular weight and barrier properties. PLA2M showed approximately 21% reduction in its water vapor permeability (WVP) as compared to PLA (control bilayer functional film). No significant differences were observed between both PLA and PLA2M in terms of their thermal properties and O2 permeability. Molecular weight of PLA2M had a slight decreased than that of PLA after processing. A significant change was observed in the IR spectra of PLA2M especially for the carbonyl stretching (1749 cm−1), and -C-O-C aliphatic ester bending (1132 cm−1), which due to the structure of astaxanthin that consists of polyunsaturated alkenes and carbonyl group. Diffusion of astaxanthin from PLA films into 95% ETOH at 30 and 40 °C were 12.7 and 22.8 × 10−11 cm2/s, respectively. New crystal domains were formed for the samples exposed to 95% ETOH at 30 and 40 °C due to solvent induced crystallization, with higher temperature inducing larger crystallization. Pouches made of PLA2M were able to maintain the freshness of soybean oil at 30 °C, under light exposure to less than 5 days per guideline by the Codex Alimentarius (<10 milliequivalent/kg), and could be attributed to the slow release of astaxanthin. [ABSTRACT FROM AUTHOR]