Study on quality change mechanism of green turnip slices during low pressure superheated steam drying based on sensitivity analysis method

Abstract Low pressure superheated steam drying (LPSSD) is an attractive drying method, which can retain nutrients in fruits and vegetables well. To obtain high quality drying products, it is necessary to understand the main factors affecting the quality attribute of drying sample. Therefore, green turnip was selected as the drying sample and sensitivity analysis method was used to identify the main influencing factors of product quality, such as color, re-hydration performance and Vitamin C during LPSSD. The results showed that the drying temperature had the greatest influence on the color change and vitamin C retention of green turnip. The total color difference ΔE* increased with the elevated drying temperature. The drying pressure had the greatest influence on re-hydration performance and the re-hydration ratio decreased with the elevated drying pressure.

Download Full-text

Influence of steam condensation on vitamin C retention in green turnip undergoing low pressure superheated steam drying

Journal of Food Process Engineering ◽

10.1111/jfpe.12898 ◽

2018 ◽

Vol 41 (8) ◽

pp. e12898

Author(s):

Jianbo Liu ◽

Qing Xu ◽

Yapeng Shi ◽

Ruifang Wang ◽

Zhanyong Li

Keyword(s):

Vitamin C ◽

Superheated Steam ◽

Low Pressure ◽

Steam Condensation ◽

Superheated Steam Drying ◽

Steam Drying

Download Full-text

Low pressure superheated steam drying of onion slices: kinetics and quality comparison with vacuum and hot air drying in an advanced drying unit

Journal of Food Science and Technology ◽

10.1007/s13197-018-3379-4 ◽

2018 ◽

Vol 55 (10) ◽

pp. 4311-4320 ◽

Cited By ~ 5

Author(s):

Rachna Sehrawat ◽

Prabhat K. Nema

Keyword(s):

Superheated Steam ◽

Low Pressure ◽

Hot Air Drying ◽

Air Drying ◽

Hot Air ◽

Superheated Steam Drying ◽

Steam Drying

Download Full-text

Drying of pineapple slices using combined low-pressure superheated steam and vacuum drying

International Journal of Food Engineering ◽

10.1515/ijfe-2021-0151 ◽

2021 ◽

Vol 0 (0) ◽

Author(s):

Jingcheng Wang ◽

Qing Xu ◽

Jianbo Liu ◽

Shuaishuai Zheng ◽

Ruifang Wang ◽

...

Keyword(s):

Superheated Steam ◽

Retention Rate ◽

Sugar Content ◽

Low Pressure ◽

Vacuum Drying ◽

Drying Time ◽

Superheated Steam Drying ◽

Health Demand ◽

Steam Drying ◽

Material Temperature

Abstract A method of combining low-pressure superheated steam drying (LPSSD) and vacuum drying (VD) was proposed to improve the dried pineapple quality and increase the drying rate. It was found that the inversion temperature in low-pressure superheated steam drying of pineapple was 85.75 °C in terms of the first falling rate period. The combining drying (LPSSD–VD) reduced the maximum material temperature by 9.5 °C and 0.35 °C, and shortened the drying time by 50 min and 90 min compared with LPSSD and VD at the same drying temperature of 90 °C. The vitamin C retention rate of dried pineapple by LPSSD–VD was 29.33% and 15.94% higher than that of LPSSD and VD, respectively. The color of dried pineapple was also improved. Moreover, the sugar content of dried pineapple can be well controlled to meet the health demand of low sugar and ensure the taste of dried pineapple during LPSSD–VD process.

Download Full-text

Superheated Steam Drying of Black Tea and Quality Improvement

International Journal of Food Engineering ◽

10.1515/ijfe-2018-0185 ◽

2018 ◽

Vol 14 (9-10) ◽

Cited By ~ 2

Author(s):

N. Rumaisa ◽

M. R. Norazatul Hanim ◽

C. L. Hii

Keyword(s):

Activation Energy ◽

Superheated Steam ◽

Moisture Transfer ◽

Black Tea ◽

Tea Leaves ◽

Drying Characteristics ◽

Drying Temperature ◽

Superheated Steam Drying ◽

Effective Diffusivities ◽

Steam Drying

AbstractThe effects of drying temperature (120 °C to 200 °C) on drying characteristics of black tea leaves using superheated steam dryer (SHS) were investigated. It was observed that increased drying temperature caused higher drying rate that helped to shorten drying times. The effective diffusivities of moisture transfer in SHS ranged between 2.30 × 10–10 and 3.90 × 10–10 m2/s within the temperature range tested. The effective diffusivities were correlated by Arrhenius relationship with Arrhenius constant and activation energy estimated at 1.07 × 10–8 m2/s and activation energy 12.34 kJ/mol, respectively. Increased in drying temperature and time significantly decreased the brightness (*L) of tea leaves from 26.34 to 22.66 and TPC from 87.93 to 42.39 mg/g. However, comparison to commercial black tea showed that SHS dried-tea leaves exhibited better colour attribute and 91.4% higher in phenolic content.

Download Full-text