This study investigated pulsed ultraviolet (PUV) illumination at different distances from the PUV source on soybean lipoxygenase (LOX) (0.4 mg/mL in 0.01 M Tris-HCl buffer, pH 9) activity. Samples (5 mL) were illuminated for 1, 2, 4, 8, and 16 s at 3 distances 6, 8.5, and 11 cm from the PUV lamp's quartz window. The temperature of 33.5 ± 1.8°C was observed for the highest treatment time of 16 s at the shortest distance of 6 cm, and resulted in a 3.5 log reduction (99.95%) in initial LOX activity. Illumination time and distance from the lamp significantly (P ≤ 0.05) affected LOX inactivation. Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) was performed on treated LOX samples and further protein profile for treated LOX filtrate (≤10 kDa), was analyzed by reverse phase high-performance liquid chromatography (RP-HPLC). The protein profile analysis revealed that LOX protein degradation was influenced significantly (P ≤ 0.05) by PUV illumination time.

Power ultrasound reduces the traditional corn steeping time from 18 to 1.5 h during tortilla chips dough (masa) processing. This study sought to examine consumer (n = 99) acceptability and quality of tortilla chips made from the masa by traditional compared with ultrasonic methods. Overall appearance, flavor, and texture acceptability scores were evaluated using a 9-point hedonic scale. The baked chips (process intermediate) before and after frying (finished product) were analyzed using a texture analyzer and machine vision. The texture values were determined using the 3-point bend test using breaking force gradient (BFG), peak breaking force (PBF), and breaking distance (BD). The fracturing properties determined by the crisp fracture support rig using fracture force gradient (FFG), peak fracture force (PFF), and fracture distance (FD). The machine vision evaluated the total surface area, lightness (L), color difference (ΔE), Hue (°h), and Chroma (C*). The results were evaluated by analysis of variance and means were separated using Tukey's test. Machine vision values of L, °h, were higher (P < 0.05) and ΔE was lower (P < 0.05) for fried and L, °h were significantly (P < 0.05) higher for baked chips produced from ultra-sonication as compare to traditional. Baked chips texture for ultra-sonication was significantly higher (P < 0.05) on BFG, BPD, PFF, and FD. Fried tortilla chips texture were higher significantly (P < 0.05) in BFG and PFF for ultra-sonication than traditional processing. However, the instrumental differences were not detected in sensory analysis, concluding possibility of power ultrasound as potential tortilla chips processing aid.

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The objective of the present study was to predict column design parameters using mathematical models such as bed depth service time (BDST) and the empty bed residence time (EBRT). The dynamic adsorption/desorption of anthocyanins from blueberry water extracts was conducted on Amberlite FPX-66 resin in a fixed bed column system. Blueberry anthocyanins were extracted with acidified hot water (90 8C) utilizing high power ultrasound. Breakthrough curves were obtained at different bed depths (5, 7.5, 10, 12.5 and 15 cm) and constant flow rate of 4.0 mL/ min. Increase in bed height increased both the breakpoint and exhaustion point of the FPX-66 resin. The experimental data fitted well to BDST model at 5% of the breakthrough curve (R 2 5 0.9864). The EBRT was in the range of 3.75-10.25 min at different bed depths. In addition, desorption of anthocyanins was studied at different ethanol concentrations and sigmoid equation was applied to obtain maximum recovery rates. PRACTICAL APPLICATIONSAnthocyanins are antioxidant flavonoids in blueberries. They are responsible for the blue color of the berries and are known to promote better health by preventing chronic diseases. A concentrated anthocyanin extract from blueberries has the potential to be used as dietary supplement, natural colorant and functional food ingredient. This present study optimized resin adsorption method to concentrate polyphenols and remove sugars using mathematical models. Optimization of the column design parameters can be used in designing a pilot/industrial scale column for the separation and concentration of anthocyanins from blueberries.