Abstract
Objective:In order to explore the effect of step-down relative humidity drying strategy on the drying characteristics of agricultural products.Methods:Yam slices were selected as the object. The effects of constant humidity drying (relative humidity 15%, 25%, 35%, 45%) and step-down relative humidity drying (relative humidity 45% in the first stage for different times of 10, 20, 30, 60 min and relative humidity 20% in the second stage) on the drying characteristics of yam slices were studied at 60 ℃; The multi-field coupling model was constructed for the simulation of heat and mass transfer; The rehydration ratio and microstructure of the dried product were also measured.Results:① During constant humidity drying, the drying rate decreased with the increase of relative humidity; However, the drying time of step-down relative humidity drying (45% relative humidity maintained for 20 min and then decreased to 15%) was 8.3% shorter than that of constant humidity drying (relative humidity 15%). ② The drying rate of yam slices generally increased first and then decreased, The fitting results of drying model showed that it was accurate to describe the changing process of moisture and mass transfer. ③ The rehydration ratio increased first and then decreased with the increase of relative humidity; Under special drying condition of step-down relative humidity drying strategy (relative humidity 45% kept for 20 min and then decreased to 15%), the yam slices showed honeycomb porous structure, which was good for the mass transfer. Under this condition, the maximum rehydration ratio was 6.85 ± 0.05; Under the drying condition of constant humidity strategy (relative humidity is 20%), the microstructure of yam sllices begin to shrink and collapse, which led to a lower rehydration rate.Conclusion:During the process of hot air drying, the multi-field coupling model can significantly shorten the drying time, effectively improve the microstructure of materials and improve the rehydration rate of products; The multi-field coupling model can precisely simulate the heat and mass transfer process in yam slices during hot air drying; The research results can provide theoretical basis and technical support for the application and optimization of step-down relative humidity drying strategy.
Publication Date
7-4-2022
First Page
113
Last Page
120
DOI
10.13652/j.issn.1003-5788.2022.01.018
Recommended Citation
Wei-peng, ZHANG; Meng-yue, HAN; Hao-yu, JU; Hong-wei, XIAO; and Xiao-zhi, FAN
(2022)
"Drying efficient improvements with step-down relative humidity and multi-field coupling model construction during hot air drying of yam slices,"
Food and Machinery: Vol. 38:
Iss.
1, Article 18.
DOI: 10.13652/j.issn.1003-5788.2022.01.018
Available at:
https://www.ifoodmm.cn/journal/vol38/iss1/18
References
[1] 段柳柳,段续,任广跃.怀山药微波冻干过程的水分扩散特性及干燥模型[J].食品科学,2019,40(1):31-38.DUAN Liu-liu,DUAN Xu,REN Guang-yue.Water diffusion characteristics and microwave vacuum freeze-drying modelling of chinese yam(Dioscorea opposite)tubers[J].Food Science,2019,40(1):23-30.
[2] 李书华,闫泽华,张仲欣,等.怀山药热泵干燥工艺研究[J].粮食加工,2017(6):49-53.LI Shu-hua,RAN Ze-hua,ZHANG Zhong-xin,et al.Technology research of Chinese yam heat pump drying[J].Grain Processing,2017(6):49-53.
[3] 骆航,孙兴力,刘金凤.热风干燥对山药片品质特性的影响[J].北方农业学报,2019,47(5):100-104.LUO Hang,SUN Xing-li,LIU Jin-feng.Effect of hot air drying on quality characteristics of Chinese yam slices[J].Journal of Northern Agriculture,2019,47(5):100-104.
[4] 曲文娟,凡威,马海乐,等.核桃滚筒催化红外—热风干燥试验及能耗分析[J].食品与机械,2021,37(5):163-168,193.QU Wen-juan,FAN Wei,MA Hai-le,et al.Experiment and energy consumption analysis of walnut drum catalytic infrared-hot air drying[J].Food & Machinery,2021,37(5):163-168,193.
[5] OJEDIRAN J O,OKONKWO C E,ADEYI A J,et al.Drying characteristics of yam slices(Dioscorea rotundata)in a convective hot air dryer:Application of ANFIS in the prediction of drying kinetics[J].Heliyon,2020,6:e03555.
[6] SONG X Y,HU H,ZHANG B L.Drying characteristics of Chinese Yam(Dioscorea opposita Thunb.)by far-infrared radiation and heat pump[J].Journal of the Saudi Society of Agricultural Sciences,2018,17:290-296.
[7] JU H Y,ZHAO S H,MUJUMDAR A S,et al.Energy efficient improvements in hot air drying by controlling relative humidity based on Weibull and Bi-Di models[J].Food Bioprod Process,2018,111:20-29.
[8] 巨浩羽,张茜,郭秀良,等.基于监测物料温度的胡萝卜热风干燥相对湿度控制方式[J].农业工程学报,2016,32(4):269-276.JU Hao-yu,ZHANG Qian,GUO Xiu-liang,et al.Control method of relative humidity of carrot hot air drying based on detecting material’s temperature[J].Transactions of the Chinese Society of Agricultural Engineering,2016,32(4):269-276.
[9] 巨浩羽,肖红伟,郑霞,等.干燥介质相对湿度对胡萝卜片热风干燥特性的影响[J].农业工程学报,2015,31(16):296-304.JU Hao-yu,XIAO Hong-wei,ZHENG Xia,et al.Effect of hot air relative humidity on drying characteristics of carrot slabs[J].Transactions of the Chinese Society of Agricultural Engineering,2015,31(16):296-304.
[10] DAI J W,RAO J Q,WANG Dong,et al.Process-based drying temperature and humidity integration control enhances drying kinetics of apricot halves[J].Drying Technology,2015,33(12):365-376.
[11] 巨浩羽,赵士豪,赵海燕,等.干燥介质相对湿度对西洋参根干燥特性和品质的影响[J].中草药,2020,51(3):631-638.JU Hao-yu,ZHAO Shi-hao,ZHAO Hai-yan,et al.Effect of relative humidity on drying characteristic and quality of Panacis Quinque folii Radix[J].Chinese Traditional and Herbal Drugs,2020,51(3):631-638.
[12] 肖扬波,刘琪,彭逸斯,等.干燥方法对茯苓产品显微性状、营养成分及抗氧化活性的影响[J].食品与机械,2021,37(3):175-179.XIAO Yang-bo,LIU Qi,PENG Yi-si,et al.The effect of drying methods on the microscopic properties,ingredients and antioxidant activity of Poria cocos products[J].Food & Machinery,2021,37(3):175-179.
[13] 曲文娟,凡威,马海乐,等.滚筒催化红外—热风联合干燥核桃的贮藏特性[J].食品与机械,2021,37(6):168-173,240.QU Wen-juan,FAN Wei,MA Hai-le,et al.Storage properties of walnuts dried by drum catalytic infrared-hot air[J].Food & Machinery,2021,37(6):168-173,240.
[14] JU H Y,LAW C L,FANG X M,et al.Drying kinetics and evolutionof the sample's core temperature and moisture distribution of yam slices(Dioscorea alata L.)during convective hot-air drying[J].Dry Technol,2016,8(11):9 435-9 441.
[15] PHAM N D,KHAN M I H,KARIM M A.A mathematical model for predicting the transport process and quality changes during intermittent microwave convective drying[J].Food Chemistry,2020,325:126932.
[16] 邹三全,刘显茜,赵振超,等.猕猴桃切片流化床干燥特性与干燥动力学模型研究[J].食品与机械,2021,37(4):150-156.ZOU San-quan,LIU Xian-xi,ZHAO Zhen-chao,et al.Study on drying characteristics and drying kinetic model of kiwi fruit slices in fluidized bed[J].Food & Machinery,2021,37(4):150-156.
[17] ONWUDE D I,HASHIM N,ABDAN K,et al.Modelling of coupled heat and mass transfer for combined infrared and hot-air drying of sweet potato[J].Journal of Food Engineering,2018,228:12-24.
[18] PASBAN A,SADRNIA H,MOHEBBI M,et al.Spectral method for simulating 3D heat and mass transfer during drying of apple slices[J].Journal of Food Engineering,2017,212:201-212.
[19] OKE M O,AWONORIN S O,OYELADE O J,et al.Some thermo-physical properties of yam cuts of two geometries[J].African Journal of Biotechnology 2009,8(7):1-8.
[20] 贺健,易军鹏,李欣,等.酸菜微波真空冷冻干燥工艺及复水特性研究[J].食品与机械,2020,36(8):109-116.HE Jian,YI Jun-peng,LI Xin,et al.Study on microwave vacuum freeze drying technology and rehydration characteristics of sauerkraut[J].Food & Machinery,2020,36(8):109-116.
[21] OGAWA T,CHUMA A,AIMOTO U,et al.Effects of drying temperature and relative humidity on spaghetti characteristics[J].Drying Technology,2017,35(10):1 214-1 224.
[22] AGNIHOTRI V,JANTWAL A,JOSHI R.Determination of effective moisture diffusivity,energy consumption and active ingredient concentration variation in inula racemosa,rhizomes during drying[J].Industrial Crops & Products,2017,106:40-47.
[23] BARATI E,ESFAHANI J A.A new solution approach forsimultaneous heat and mass transfer during convective drying of mango[J].Journal of Food Engineering,2011,102(4):302-309.
[24] URIBE E,VEGA-GLVEZ A,SCALA K D,et al.Characteristics of convective drying of pepino fruit(Solanum muricatum ait.):Application of Weibull distribution[J].Food & Bioprocess Technology,2011,4(8):1 349-1 356.