Effect of infrared ray roasting on oxidation stability and flavor of virgin rapeseed oils.

Effects of infrared ray roasting (IRR) on the oxidation stability and flavors of virgin rapeseed oil (VROs) at 110-170°C were investigated and compared with traditional roller roasting (TRR). Results showed that IRR samples showed lower acid and peroxides values, higher oxidation stability index, and 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity than TRR ones. IRR samples displayed better thermal expansion of rapeseed for internal fragmentation from microstructures, which facilitated the release of tocophenols (652.63-748.78 mg/kg) and 4-vinylsyringol (7.54-678.19 mg/kg), compared with TRR ones with tocophenols (652.63-689.28 mg/kg) and 4-vinylsyringol (7.54-524.18 mg/kg) contributing to better oxidation stability. Moreover, important volatile compounds, including pyrazines, isothiocyanates, nitriles and aldehydes, were formed quantitatively more in IRR than TRR samples, which was attributed to better heat transfer efficiency and internal fragmentation promoting complex reactions inside rapeseed. Therefore, IRR has more positive roasting effects on VROs than TRR. PRACTICAL APPLICATION: Virgin rapeseed oil is a massively consumed flavor vegetable oil, but the traditional high-temperature roller seed roasting process can cause serious quality problems. Our work applied a novel roasting technology, infrared ray roasting to rapeseed pretreatment. The results show that this new type of roasting technology is more efficient and stable and has important applications in the production of virgin rapeseed oil with better oxidative stability and flavor.

Effect of Post-Harvest LED and UV Light Irradiation on the Accumulation of Flavonoids and Limonoids in the Segments of Newhall Navel Oranges (Citrus sinensis Osbeck).

To investigate the effect of post-harvest light irradiation on the accumulation of flavonoids and limonoids, harvested Newhall navel oranges were continuously exposed to light-emitting diode (LED) and ultraviolet (UV) light irradiation for 6 days, and the composition and content of flavonoids and limonoids in the segments were determined using UPLC-qTOF-MS at 0, 6, and 15 days after harvest. In total, six polymethoxylated flavonoids (PMFs), five flavone-O/C-glycosides, seven flavanone-O-glycosides, and three limonoids were identified in the segments. The accumulation of these components was altered by light irradiation. Red and blue light resulted in higher levels of PMFs during exposure periods. The accumulation of PMFs was also significantly induced after white light, UVB and UVC irradiation were removed. Red and UVC irradiation induced the accumulation of flavone and flavanone glycosides throughout the entire experimental period. Single light induced limonoid accumulation during exposure periods, but limonoid levels decreased significantly when irradiation was removed. Principal component analysis showed a clear correlation between PMFs and white light, between flavonoid glycosides and red light and UVC, and between limonoids and UVC. These results suggest that the accumulation of flavonoids and limonoids in citrus is regulated by light irradiation. White light, red light and UVC irradiation might be a good potential method for improving the nutrition and flavor quality of post-harvest citrus.

Stability of midazolam in syrspend SF and syrspend SF cherry.

Midazolam is a short-acting benzodiazepine central nervous system depressant available as an injection, tablet, or oral syrup. The need for alternative dosage form options for patients unable to take tablets and shortages of other forms of the drug have led compounding pharmacies to seek alternatives, mainly solutions and suspensions. Additionally, some patients are unable to use suspending agents containing alcohol or sorbitol. The objective of this study was to determine the stability of midazolam in sorbitol-free, alcohol-free SyrSpend SF and SyrSpend SF Cherry suspending agents. The studied samples were compounded into a 1-mg/mL suspension and stored in low-actinic plastic bottles at temperatures between 2 degrees C to 8 degrees C and at room temperature conditions. Six samples were assayed at each time point out to 58 days by a stability-indicating high-performance liquid chromatography method. The method was validated for its specificity through forced-degradation studies. The samples remained within 90% to 110% of the initial concentration throughout the course of the study. Based on the data collected, the beyond-use date of these preparations is at least 58 days when protected from light at both refrigerated and room temperature storage conditions.

Photosensitized degradation of losartan potassium in an extemporaneous suspension formulation.

During development of an extemporaneous suspension formulation for losartan potassium, previously unknown degradation products were observed in experimental suspensions prepared in a commercial cherry syrup vehicle. These degradates increased rapidly when analytical solutions prepared from that suspension were exposed to ambient light. The structures of the degradates were determined using a combination of preparative HPLC, LC/MS, (13)C and (1)H NMR (1D and 2D), and mechanistic chemistry. Each degradate results from destruction of the imidazole ring of losartan. Formation of the two major degradates required exposure to light (UV or visible) and the presence of oxygen. Experiments using Rose Bengal (a singlet oxygen photosensitizer) and 1,4-diazabicyclooctane (DABCO; a singlet oxygen quencher) established that the major photodegradates are formed via the intermediacy of singlet oxygen. The identity of the photosensitizer in the formulation was not unequivocally determined; however, the experiments implicated the artificial flavoring in fulfilling this role.

Effects of gamma irradiation on the flavor composition of food commodities.

Fifteen food products including potato, sweet potato, shallot, onion, garlic, ginger, papaya, mango, rice, tobacco, small red bean, mungbean, soybean, wheat, flour and spices have been approved for irradiation by the National Health Administration in Taiwan. Market tests (Wu et al., 1996) provided strong proof that Taiwanese consumers would accept irradiated foods. However, researchers in the food industry are concerned about the possibility of chemical changes, especially in volatile composition, during irradiation processing. This study considers several food commodities, including garlic, ginger, shiitake, onion, potato, day-lily, tilapia, silver carp and shrimp. Food samples were irradiated with optimum doses and then studied for possible occurrence of chemical changes and effects on compositional characteristics of foods.

Photochemical reactions of flavor compounds.

Photochemical reaction is a chemical reaction which is initiated by light. In addition to light, photosensitizer and oxygen are the two important factors which contribute to the formation of photochemical products. In this contribution, photochemical reactions of flavor compounds are classified into four categories according to the factors of photosensitizer and oxygen. Photochemical reaction with or without sensitizer in the absence of oxygen and unsensitized photochemical reaction in the presence of oxygen usually involve free radical reactions; while in the presence of oxygen and sensitizer, the singlet oxygen can be generated that then reacts with flavor compounds which contain double bonds to give the oxygenated products.