Impacts of different drying strategies on drying characteristics,the retention of bio-active ingredient and colour changes of dried Roselle

The drying kinetics of Roselle （Hibiscus sabdariffa L） of variety Terengganu （UMKL-1） and the quality attribution of Roselle were studied. The experiments were conducted using four different drying methods, including solar greenhouse drying （SD）, solar greenhouse with intermittent heat pump drying （SIHP）, hot air drying （HA） and heat pump drying （HP）. Among the four drying methods, HP achieved the highest drying rate at a range from 0.054 g H20-（g DM）-1. rain-1 to 0.212 g H20-（g DM）-1. rain 1 while SD had the lowest drying rate, measured at 0.042 g H2O. （g DM） 1.min- 1. The analysis on colour kinetics revealed that there is no significant colour loss （p 〉 0.05） observed from HP＇s dried Roselle. Greater amount of flavonoid compounds i.e. protocatechuic acid was found in SD and SIHP dried finished product whereas HP＇s dried Roselle contains higher percentage of catechin as compared to other drying methods.

Influence of colour changes and moisture content during banana drying on laser backscattering

Pre-drying treatments are frequently employed to preserve fruit quality.The objective of this research was to monitor colour changes of banana during drying by laser backscattering and to determine the influence of the fruit discolouration on the light distribution into banana tissue.Moreover,to examine the influence of drying on the laser backscatter,the relationship between moisture content and relative laser area of banana slices was analyzed with different degrees of colour degradation.The experiments were conducted at drying air temperature of 63℃with various pre-treatments like chilling,soaking in ascorbic/citric acid and dipping in distilled water.An untreated sample was used as a control.A laser diode emitting at 670 nm with 3 mW power was used as light source.The backscattering relative laser area was used as an indicator for the light absorption into the tissue.The high result achieved on coefficient of determination R^(2)(>0.93)confirmed linear relationship between relative laser area and moisture content.Treatment with ascorbic acid gave the best prediction of the moisture content with the standard error of 5.7 and 8.8 for the estimated intercept and slope.The results showed a significant difference of lightness(L*values)during drying according to the different treatments.As a result,colour degradation did not have a significant influence on the absorption of light at 670 nm wavelength.

High Solar Energy Absorption and Human Body Radiation Reflection Janus Textile for Personal Thermal Management

A large of energy consumption is required for indoor and outdoor personal heating to ameliorate the comfortable and healthy conditions.Main personal thermal management strategy is to reflect mid-infrared human body radiation for human surface temperature(THS)regulation.We demonstrate a visible Janus light absorbent/reflective air-layer fabric(Janus A/R fabric)that can passively reflect radiative heating meanwhile can actively capture the solar energy.A series of azobenzene derivatives functionalized with alkyl tails are reported to co-harvest the solar and phase-change energy.The THS covered by Janus A/R fabric can be heated up to~3.7°C higher than that covered by air-layer fabric in cold environment(5°C).Besides,integrating the thermo-and photo-chromic properties is capable of monitoring comfort THS and residue energy storage enthalpy,respectively.According to the colour monitors,intermittent irradiation approach is proposed to prolong comfortable-THS holding time for managing energy efficiently.