No abstract

In a conventional desiccant packed bed dehumidification, the adsorption and desorption operations switched at a constant cycle. However, this Conventional Steady Cyclic (CSC) operation was not performed well under disturbances. Therefore, a Temperature Breakpoint Cyclic (TBC) operation is proposed. A numerical model of the desiccant packed bed dehumidification system has been constructed and validated. The model was then used to assess the desiccant packed bed dehumidification performances in term of moisture removal capacity (MRC) and dehumidification coefficient of performance (DCOP) under various cycle times and temperature factors. The calculation results showed that under CSC, larger amounts of energy were required in the desorption operation, while the TBC exhibited higher performances in term of both MRC and DCOP. Notably, at a high regeneration temperature, the MRC of the TBC was 10% higher than the CSC’s; moreover, the DCOP of the TBC was twice higher than the CSC’s. In other words, at high recovery temperature, both operations exhibited comparable capacities while the energy cost was halved under TBC operation.

The objective of this study is to evaluate shelf life of instant pasta which had been packed in two different packaging, type I is an OPP/MCPP sachet and type II is an OPP/CPP sachet, under accelerated condition (37°C, 85%RH) for 12 weeks. There were 2 index which were used to evaluate the shelf life, one was sensory tests and another one was moisture content in pasta. Assessed by sensory tests, the shelf life of instantly cooked pasta packed in type I and type II sachet, were revealed more than 12 weeks and equal 12 weeks, respectively. Likewise, the shelf life predicted on the basis of moisture sorption isotherm and water permeability of packaging material, were estimated at 119 and 46 days in OPP/MCPP and OPP/CPP sachets, respectively. According to these results, the quality changing of instant pasta measured during storage suggested that OPP/MCPP sachet had better protectively effect than the OPP/CPP sachet.