Black pepper (piper nigrium L.) is a spice commonly used but has a problem with microbial control, so it needs non-thermal decontamination method for product quality of dried foods. Intense pulsed light (IPL) technology is a non-thermal method for superficial decontamination of foods to inactivate pathogenic microorganisms by using high peak power and short duration pulses of a broad-spectrum (170-2600 nm) using a xenon lamp. The objective of this study was to reduce total number of bacteria in ground black pepper effectively by combined treatments of IPL and immobilized TiO2 photocatalyst. Self-designed cyclone type of pilot-scaled IPL device (> 5 kg/h) was used, which makes samples to flow cyclonically in a vacuum space longer time rather than moving vertically. Using this device alone, without TiO2 coated, 0.3-0.6 log reductions were achieved under a total energy fluence of 14.85 J/cm2 (DC voltage; 1200, 1800, and 2400 V, pulse duty; 0.5, 2.1, and 3.0 ms, treatment time; 60, 120, 180, 240, and 300 s, frequency; 2 Hz). Subsequently, TiO2-coated quartz plates with different layers between light source and samples were installed to observe the effect of photocatalyst and the efficiency of decontamination was improved slightly. However to increase the effect of the photocatalyst, several factors (TiO2 particle size, TiO2 film thickness and transparency, adhesiveness between quartz and photocatalyst, etc.) need to be concerned additionally. Nevertheless, the application of IPL treatment combined with TiO2 photocatalyst offers a potential of effective non-thermal decontamination method for dealing with powder foods in food industry.
This study was conducted to evaluate characteristics of bread and rheology of flour dough containing fructooligosaccharide. In the farinogram test, addition of fructooligosaccharide changed stability and development time. Stability and development time increased as the amount of fructooligosaccharide increased. In the extensograph test, the degree of extension decreased with increasing of fructooligosaccharide content, whereas degree of resistance increased. The volume of the loaf bread containing 10% fructooligosaccharide was the largest, and the bread containing 15% fructooligosaccharide revealed the best taste, flavor, and texture scores. After fermentation treatment, the volume of the dough with 20% of sucrose were less than that of 20% of fructooligosaccharide. Dough with 20% of sucrose revealed lowest dough raising power compared to other doughs. Overall, preference scores by sensory evaluation of bread containing fructooligosaccharide were higher than that of bread with sucrose. Therefore, excellent quality of bread may be achieved by adding fructooligosaccharide instead of sucrose to the process.
This study investigated the antibacterial effects of Galla rhois extract (GRE) against Campylobacter jejuni and Campylobacter coli. The minimum inhibitory concentrations (MICs) of GRE against C. jejuni and C. coli were 0.28 and 0.55 mg/mL, respectively, and the corresponding minimum bactericidal concentrations (MBCs) were 4.4 and 5.5 mg/mL. C. jejuni treated with the MIC, MBC or 2×MBC of GRE showed significant inhibition of growth compared with that of the control group during the incubation period, and no viable bacteria were detected at 24 h after incubation. C. coli treated with MIC, MBC or 2×MBC of GRE also showed inhibition of growth compared with that of the control group during the incubation period, and in the C. coli cultures treated with MBC and 2×MBC of GRE, no viable bacteria were detected at 24 h after incubation. In conclusion, GRE is a candidate antibacterial agent against C. jejuni and C. coli, and may have applications for the control of Campylobacter infection in poultry.
Phellinus linteus (PL), one of the immune-regulatory substances, is recognized to play the role in the metabolic process on inflammation and immunity. It has been traditionally used in the oriental medicine to treat inflammatory related disease. The purpose of this study was to evaluate the effects of water extracts of PL on the mesenteric lymph node lymphocytes immune function in the ICR male mice. Control mice received vehicle only. The PL treated mice were administered the respective extract by oral gavages for 4 weeks. IgE concentrations in serum and MLN lymphocytes were significantly lower in PL treated mice than in control mice. PL increased the proportion of CD4+ and CD8+ T cells in MLN lymphocytes. PL significantly decreased Th2 cytokine concentrations and mRNA expression levels in cytokine secretions. Therefore, water extracts of PL modulate inflammatory parameters through regulation of immunoglobulin production resulting from decreased Th2 cytokine secretion and mRNA expression levels and reduce pro-inflammatory cytokine secretion and mRNA expression in MLN lymphocytes.