Smart NMR Method of Measurement of Moisture Content of Vegetables During Microwave Vacuum Drying

Microwave drying is usually combined with vacuum environment in conjunction with hot air flow to draw the moisture rapidly. The moisture content of the vegetables undergoing drying is hard to measure online. This research designed a microwave vacuum drying (MVD)-low-field nuclear magnetic resonance (NMR) smart device and investigated the feasibility of NMR method for online measurement of state of moisture during MVD. The relation between the signal amplitude (A2) and the true moisture content (M1) of six kinds of vegetables (mushroom, carrot, potato, lotus, edamame, vegetable corn) was fitted to estimate if NMR can measure the M1 of vegetables directly. Results showed that A2 and M1 of different fresh vegetables had no single empirical mathematical model to fit. However, for each kind of these vegetables, the A2 and corresponding M1 in different MVD stages showed a significant linear relationship. The predicted moisture content (M2) of mushroom: M2 = 5.25351 × 10−4A2 − 0.34042, R = 0.996; carrot: M2 = 5.78756 × 10−4A2 − 0.14108, R = 0.998; potato: M2 = 3.10019 × 10−4A2 − 0.10612, R = 0.991; lotus: M2 = 2.32415 × 10−4A2 − 0.01573, R = 0.998; edamame: M2 = 3.13310 × 10−4A2 − 0.4198, R = 0.996; vegetable corn: M2 = 1.69461 × 10−4A2 − 0.09063, R = 0.995. The linear models between M2 and A2 were able to estimate the end point (M1 < 8%) of MVD with a high accuracy (P > 0.950).

[1]  Yuan-Yuan Pu,et al.  Combined hot-air and microwave-vacuum drying for improving drying uniformity of mango slices based on hyperspectral imaging visualisation of moisture content distribution , 2017 .

[2]  Xiaojing Li,et al.  Effect of cooking on physicochemical properties and volatile compounds in lotus root (Nelumbo nucifera Gaertn). , 2017, Food chemistry.

[3]  Jian-hua Huang,et al.  Qualitative and quantitative analyses of Compound Danshen extract based on 1H NMR method and its application for quality control. , 2016, Journal of pharmaceutical and biomedical analysis.

[4]  J. Marchetti,et al.  Mathematical modelling of the drying kinetics of Hass avocado seeds , 2016 .

[5]  K. Movagharnejad,et al.  Mathematical modeling and experimental analysis of potato thin-layer drying in an infrared-convective dryer , 2016 .

[6]  Xiao Dong Chen,et al.  Investigation on water status and distribution in broccoli and the effects of drying on water status using NMR and MRI methods. , 2017, Food research international.

[7]  M. Zhanga,et al.  Trends in microwave-related drying of fruits and vegetables , 2022 .

[8]  H. J. Andersen,et al.  The significance of cooling rate on water dynamics in porcine muscle from heterozygote carriers and non-carriers of the halothane gene-a low-field NMR relaxation study. , 2003, Meat science.

[9]  Optimization of colour parameters and drying effici ency in osmotically pretreated microwave assisted drying of yellow sweet pepper ( Capsicum annum L.) using Response-Surface Methodology , 2014 .

[10]  Srivastava A.K,et al.  Modeling and Evaluation of Thermal Diffusivity and Activation Energy of Potato slices in Forced Convection Multi Tray Solar Dryer , 2015 .

[11]  Vaios T. Karathanos,et al.  Comparison of Two Methods of Estimation of the Effective Moisture Diffusivity from Drying Data , 1990 .

[12]  A. Mujumdar,et al.  A Comparative Study of Four Drying Methods on Drying Time and Quality Characteristics of Stem Lettuce Slices (Lactuca sativa L.) , 2014 .

[13]  Mercedes Careche,et al.  Low field nuclear magnetic resonance (LF-NMR) relaxometry in hake (Merluccius merluccius, L.) muscle after different freezing and storage conditions. , 2014, Food chemistry.

[14]  J L Potter,et al.  NMR relaxation of protons in tissues and other macromolecular water solutions. , 1982, Magnetic resonance imaging.

[15]  Yuting Tian,et al.  Influence of microwave vacuum drying on glass transition temperature, gelatinization temperature, physical and chemical qualities of lotus seeds. , 2017, Food chemistry.

[16]  Cristina L. M. Silva,et al.  Fresh-cut melon quality during storage: An NMR study of water transverse relaxation time , 2015 .

[17]  L. Jinping,et al.  Characteristic of gas production of over-ground household thermostatic biogas digester heated by solar energy. , 2015 .

[18]  S. Gautam,et al.  Hurdle Technology Including Chlorination, Blanching, Packaging and Irradiation to Ensure Safety and Extend Shelf Life of Shelled Sweet Corn Kernels , 2015 .

[19]  Hongyuan Wei,et al.  Simulation of microwave thin layer drying process by a new theoretical model , 2017 .

[20]  U. Kulozik,et al.  Microwave-Vacuum Drying of Lactic Acid Bacteria: Influence of Process Parameters on Survival and Acidification Activity , 2016, Food and Bioprocess Technology.

[21]  Z. Emam-djomeh,et al.  Heat and mass transfer in apple cubes in a microwave-assisted fluidized bed drier , 2013 .

[22]  Fabíola Manhas Verbi Pereira,et al.  Through-package fat determination in commercial samples of mayonnaise and salad dressing using time-domain nuclear magnetic resonance spectroscopy and chemometrics , 2015 .

[23]  B. Hills,et al.  A new interpretation of proton NMR relaxation time measurements of water in food , 1990 .

[24]  Suresh Prasad,et al.  Drying kinetics and rehydration characteristics of microwave-vacuum and convective hot-air dried mushrooms , 2007 .

[25]  B. Blümich,et al.  Unilateral NMR and thermal microscopy studies of vegetable tanned leather exposed to dehydrothermal treatment and light irradiation , 2016 .

[26]  V. Chandramohan,et al.  Estimation of Equilibrium Moisture Content and Drying Time of Potato Through Hot Air Drying , 2017 .

[27]  Arun S. Mujumdar,et al.  Recent Developments in Smart Drying Technology , 2015 .

[28]  Min Zhang,et al.  Prediction of color and moisture content for vegetable soybean during drying using hyperspectral imaging technology , 2014 .

[29]  Weiqiao Lv,et al.  Study of the drying process of ginger (Zingiber officinale Roscoe) slices in microwave fluidized bed dryer , 2016 .

[30]  A. Mujumdar,et al.  The energy consumption and color analysis of freeze/microwave freeze banana chips , 2013 .

[31]  Nigel Brunton,et al.  Observations on the water distribution and extractable sugar content in carrot slices after pulsed electric field treatment. , 2014, Food research international.

[32]  A. Mujumdar,et al.  Microwave Freeze–Drying Characteristics and Sensory Quality of Instant Vegetable Soup , 2009 .

[33]  Chen Gang.  Research Progress on the Energy Reduce of Open-Type Air Drying Process of Vegetables , 2007 .

[34]  A. Mujumdar,et al.  Effect of blanching on microwave freeze drying of stem lettuce cubes in a circular conduit drying chamber , 2012 .

[35]  Xiaosong Hu,et al.  Mathematical modelling on thin layer microwave drying of apple pomace with and without hot air pre-drying , 2007 .

[36]  Villiam Bortolotti,et al.  Effect of pulsed electric field treatment on water distribution of freeze-dried apple tissue evaluated with DSC and TD-NMR techniques , 2016 .