The aim of this study was to investigate the effect of electric field on physicochemical properties and antioxidant activity of persimmon (Diospyros kaki L.). Persimmons were exposed to electric field strength of 7 kV / cm for 3, 6 or 9 d during 15 d of storage at 10 °C. Persimmons without electric field treatment was considered as a control. The results showed that fruits received electric field for 9 d remained firmer, contained higher total phenolic content and had higher antioxidant activity than the untreated control after storage for 15 d. This suggests that exposure to electric field during storage may be useful for prolonging the shelf life of persimmon; and for producing and preserving persimmon product with high total phenolic content and antioxidant capacity.

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In this study, we developed an autonomous color marker search system that uses a single pan-tilt-zoom camera to detect the 3D locations of multiple markers placed in a field. The system was designed to scan for multiple markers over a sensing range within 40 m in a field divided into 855 marker search grids. In the experiments, our system was able to robustly measure marker 3D positions within a sensing range of approximately 30 m, and with a root mean square error of less than 0.5 m, without large height differences between markers and camera, and without marker deformation, with the maximum marker search time required to scan the entire field of approximately 7 min.

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In New Zealand, aerobic mesophilic counts on fresh chicken should be < 6 log CFU cm⁻² by end of shelf-life (4 °C) as the products are susceptible to microbial contamination by spoilage and pathogenic microorganisms. Effect of UV-C light was investigated on fresh chicken samples (20 °C) using 50 to 300 mJ cm⁻² dosages. Treatment with 50 mJ cm⁻² extended the shelf-life of skin-on-fillets to day 6 and skinless-fillets to day 7 at 4 °C. This dosage had no impact on the colour and lipid oxidation of the chicken samples (p < 0.05), despite the detection of a slight burnt odour on treated fresh raw chicken samples stored for 1 d (4 °C) which was not perceived after cooking. Treatment with 50 mJ cm⁻² successfully extended the shelf life of skinless chicken portions at 4 °C (p < 0.05).

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This study investigated the effects of citric acid (CA) pretreatments and drying temperatures on quality of banana pulp and peel flours. Banana pulps and peels were pretreated with CA solution at different concentrations (0.5, 0.7, and 1.0 % w / v) and dried at 40, 60, and 80 °C. In banana pulp flour, higher CA concentration and drying temperature resulted in a lower level of water holding capacity. Resistant starch increased with increasing drying temperature. In banana peel flours, total polyphenol content increased with increasing drying temperature. Pretreating with 1.0 % CA solution and drying at 80 °C can produce good properties of the pulp flour. However, good properties of the peel flour can be achieved by pretreating with 1.0 % CA solution and drying at 60 °C.

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