This study investigated the surface tension and foaming properties of the hot-water extracts of pumpkin leaf and chickpea, as well as the effects of the plant hot-water extracts on white pan bread baking. Propylene glycol alginate (PGA), a synthetic emulsifier widely used in bakery, was used as a control. Pumpkin leaf water extract showed lower surface tension and comparable foaming capacity, compared with chickpea water extract and PGA solution when total solid  0.15% (w/w). Chickpea water extract showed the highest foam stability when total solid  0.15% (w/w). The dough was found to have a weak gel structure, and its viscoelastic properties were not significantly influenced by adding 0.05% or 0.15% (w/w) (based on total solid content) plant water extracts or PGA. The specific volume of the bread increased, and the baking loss was reduced by adding the two plant water extracts of total solid 0.15% (w/w). The hardness and chewiness of the bread crumb were reduced to a level comparable to the crumb containing 0.05% (w/w) PGA. The results showed that the pumpkin leaf water extract could be an effective natural emulsifier with a high phenolic content for bakery products.

A rapid analytical method was developed and optimized to determine gluten content in bread. Existing gluten quantification methods were inappropriate for bread with high gluten content because they were optimized to analyze shallow gluten content. To overcome this problem, the first method of quantifying the gluten content in bread was developed by modifying the gluten analysis method in cereal grains. Heat-stable gliadin was selectively quantified for gluten quantification using high-performance liquid chromatography (HPLC), and gliadin peaks were separated using an Agilent SB-C8 column. The specificity, linearity, accuracy, precision, limit of detection (LOD), and limit of quantification (LOQ) were measured for validation. The calibration curve of gliadin had high linearity (R2 = 0.9996), and LOD and LOQ were 0.03 and 0.10 g/100 g, respectively. The relative standard deviation (RSD) values of intra- and inter-day precision were less than 2.49% and 1.54%, respectively. Recovery ranged from 90.73% to 93.87%, with RSD values less than 2.06%. These results indicate that the HPLC method for quantifying gluten in bakery products is efficient, reliable, and reproducible.

The green peach aphid, Myzus persicae (Sulzer), is one of the most important insect pests in the world. We have explored the possibility of using sounds as a stressor to control this species. Five sine wave frequencies (100, 500, 1000, 5000, 10000 Hz) with combination of three intensity (66, 78, 90 dB) were used as acoustic stimuli in the playback experiments. For behavioral bioassay, we examined frequencies of honeydew production (HDP) and wagging behavior, and duration of moving behavior. The HDP occurs regularly during each stage of nymphal or mature period, and rate of the HDP indicates a degree of food consumption. Aphids conduct wagging to determine a host plant or to find a feeding site. The moving behavior may be regarded as dispersal. As results, all acoustic stimuli significantly reduced rate of the HDP and increased rate of the moving behavior. There was a significant effect to induce the moving behavior in the test of 5000 Hz. In addition, the acoustic stimuli using 5000 Hz were the most effective to disturb feeding behavior of M. persicae at an individual level.