Pretreatment of Crop Residues by Application of Microwave Heating and Alkaline Solution for Biofuel Processing: A Review

The effect of microwave-assisted alkaline pretreatments and enzymatic saccharification of lignocellulosic agricultural crop residues are reviewed. Pretreatment is a major step for the efficient and effective biochemical conversion of lignocellulosic biomass to biofuel. Microwave-assisted alkali pretreatment is one of the promising techniques used in the bioconversion of biomass into useful energy product. The advantages of microwave heating coupled with alkaline pretreatment include reduction of the process energy requirement, rapid and super heating, and low toxic compound formation. This chapter reviews recent microwave-assisted alkali pretreatment and enzymatic saccharification techniques on different agricultural residues highlighting lignocellulosic biomass treatments and reducing sugar yields, and recovery. In addition, compiled up-to-date research studies, development efforts and research findings related to microwave-assisted alkali, and enzymatic hydrolysis are provided

Processing of pulses : a platform for innovation

The paper is a guide for the food sector in identifying processing and milling strategies to achieve pulse flour/protein specifications with nutritional profiles needed for a wide range of food applications. It discusses roasting techniques that can create foods that better meet consumer demands, while also contributing to health and economic systems across agri-food value chains. Traditional processing conditions for pulses (dry beans, broad dry beans, dry peas, chickpeas, dry cowpeas, pigeon peas, lentils, Bambara beans, vetches, lupins and minor pulses) include: dehusking, splitting, soaking, germinating, drying/roasting, and or fermentation

Biodiesel Refining and Processing Strategies

Biodiesel fuel is produced from triglyceride fats, and oils obtained from plant and animal sources. Typically, triglycerides are first transesterified to produce fatty acid alkyl esters (FAAE) and then refined. Traditional FAAE refining strategies are often energy-intensive, requiring large amounts of water (e.g., wet washing), adsorbents, and/or chemicals. Refining, in turn, produces substantial amounts of waste and is accompanied by the loss of biodiesel as neutral oil entrained in waste. A wide array of methods and technologies have been developed for industrial oil purification. Successful refining practices minimize waste and limit neutral oil losses. Recent studies have explored the use of adsorbents, solvent purification processes, membrane filtration, as well as novel applications of electrostatic field treatments to remove polar impurities (including free fatty acids, residues, soaps, and glycerides), and particulates from oils. This chapter will review and compare traditional current and novel strategies for refining FAAE for use as biodiesel

Integrated dual frequency permittivity analyzer using cavity perturbation concept

Optimal utilization of microwave energy requires more basic knowledge of the dielectric properties of the material under investigation. The dielectric properties of materials subjected to microwaves are known to depend on moisture content, temperature and density of the material as well as the frequency of the applied microwave field. This thesis is focussed on the development and evaluation of the new Permittivity Analyser to measure the dielectric properties of agri-food materials at 915 and 2450 MHz using cavity perturbation concept.In this study, the dielectric properties measuring system was designed and developed using cavity perturbation concept to measure the essential and fundamental parameters of microwave-material interaction; dielectric constant and dielectric loss factor of selected agri-food substances and organic solvents. The TM010 mode of electromagnetic energy was selected and configured to operate at the peakresonant condition for both ISM (Industrial, Scientific and Medical) approved frequencies of .915 and 2450 MHz frequencies. The resonant perturbation cavities were designed, fabricated and tested using the network analyser and the permittivity analyser. High Q (ratio of energy supplied to absorbed) values were reported for both frequencies. Basic calibration of the measurement system was performed using standard media such as air, water and alcohol. Necessary mathematical steps and algorithms were written and integrated into a user-friendly software program (Visual basic 6.0) to carry out the entire measurement.The dielectric properties (epsilon' & epsilon ″) of materials such as; edible oils---canola, soya and sunflower oils, neem oil/pulp, homogenized milk (1, 2 and 3.25% fat), organic solvents such as ethanol, hexane and their mixtures were determined at various temperatures and frequency (915, 2450 MHz) combinations, using cavity perturbation technique. Linear relationships between the dielectric properties and temperature found in the literature were confirmed to be valid for certain ranges in case of edible oils, organic solvents and milk samples tested with the cavity perturbation method. Repeatibility and variability aspects of the permittivity analyzer at both the frequencies are presented

Cavity perturbation technique for measurement of dielectric properties of some agri-food materials.

Optimal utilization of microwave energy requires more basic knowledge of the dielectric properties of the material under investigation. The dielectric properties of materials subjected to microwaves are known to depend on moisture content, temperature and density of the material as well as the frequency of the applied microwave field. This thesis deals with the study of cavity perturbation technique and its feasibility to determine the dielectric properties of various agri-food materials. In the study, linear relationships between roots of the dielectric properties and density found in the literature were confirmed to be valid for pulverized grains tested with the cavity perturbation method. The effect of particle size on dielectric properties of chopped grain is also reported as a quadratic relationship. The dielectric properties (epsilon' & epsilon") of materials such as tylose (methyl hydroxy ethyl cellulose); organic solvents such as ethanol, hexane and their mixtures; edible oils such as canola, soya and sunflower oils were determined at various temperatures, frequencies, salt content and other relevant parameters, using cavity perturbation technique.L'utilisation optimale de l'énergie micro-onde requiert une connaissance approfondie des propriétés diélectriques des matériaux traités. Les propriétés diélectriques des matériaux soumis aux micro-ondes dependent du taux d'humidité, de la temperature et de la densité de la matière de même que de la fréquence du champ micro-onde. Cette etude a également examiné la méthode de perturbation de cavités et son utilisation potentielle dans le secteur agro-alimentaire. Dans cette étude, une modélisation linéaire entre la racine des propriétés diélectriques de grains haches et la densité a été validé avec la méthode de perturbation des cavités. L'effet de la grosseur des particules sur les propriétés diélectriques a été identifie comme étant quadratique. Les propriétés diélectriques de matériaux tel le tylose^MC.; de solvants comme l'éthanol et l'hexane ainsi que leur combinaison; d'huiles comestibles comme l'huile de canola, l'huile de soya ou l'huile de tournesol ont aussi été determinées à différents niveaux de temperature, fréquence, pourcentage de sels, etc. en utilisant la méthode de perturbation des cavités

Optimization of microwave vacuum drying parameters for germinated lentils based on starch digestibility, antioxidant activity and total phenolic content

The aim of this study was to optimize the processing parameters of pulse mode microwave-vacuum drying of germinated green and red lentils (CDC Greenland and CDC Maxim) and investigate the changes in their total phenolic content (TPC), total antioxidant activity (TAA) and in-vitro starch digestibility (SD). The lentils were germinated for 5 days and dried by a pulse mode microwave-vacuum method, using 2 s to 8 s out of 10 s pulsed mode at 2000W microwave power and varying the vacuum pressure level between 15 and 45 kPa. In-vitro starch digestibility increased significantly with increased microwave power level. The TPC and TAA appeared to vary distinctively in the two varieties of selected lentils. Vacuum pressure levels did not significantly (p&gt;0.05) affect any responses. Green lentils could be dried at 8 s microwave power and 45 kPa vacuum pressure and red lentils could be dried at 5.5 s microwave power and 42.19 kPa vacuum pressure. The microwave-vacuum drying showed great potential for the drying of germinated lentils.</p

Effect of drying techniques on the retention of antioxidant activities of Saskatoon berries

The main objective of this research was to compare the retention of antioxidant activity and total anthocyanin content of Saskatoon berries dried by freeze drying, microwave-vacuum drying, thin layer hot air drying and vacuum drying. Antioxidant activity of berry samples was determined by DPPH radical scavenging and ABTS radical scavenging, and the pH differential method was used to determine total anthocyanin content of the berry samples. The results showed that the freeze dried Saskatoon berries exhibited the highest retention of anthocyanin and antioxidant activity among the dried samples, followed by microwave-vacuum dried berries, thin layer hot air dried berries and vacuum dried berries. There were significant differences between the berry samples at P&lt;0.05.  DPPH radical scavenging and ABTS radical scavenging were correlated linearly with an R2 value of 0.99 at P&lt;0.05 showing their effectiveness for the determination of the antioxidant activity of the Saskatoon berries. However, the DPPH radical scavenging assay was more effective than the ABTS radical scavenging assay. The results also showed that antioxidant activity of the berries was highly correlated with the total anthocyanin content of the fruit. The reduction of anthocyanin in dried berry samples was linearly correlated with the reduction of DPPH radical scavenging with an R2 value of 0.97 at P&lt;0.05 and, also, linearly correlated with the reduction of ABTS radical scavenging with an R2 value of 0.88 at P&lt;0.05.</p

The Canadian Society for Bioengineering La Société Canadienne de Génie Agroalimentaire et de Bioingénierie Effect of microwave drying and storage on the color, breakage, dehulling and cooking quality of two red lentil varieties

Abstract. Red lentil is a nutritious and healthy food which provides nutritional and health benefits to consumers. Lentils should be harvested from the field at higher moisture content and dried to lowe

Degradation of Phenol With A Microwave-Uv Irradiation Treatment System Using NANO-TiO2

 The degradation of phenol from various industrial effluents becomes essential and studied in this work. The microwave (MW), ultra-violet (UV) and combination treatment systems were designed and TiO2 nanoparticles were used as photocatalyst for the degradation of 1500ppm phenol in a solution. It was observed that the degradation efficiency was less than 10% in both MW and MW-UV systems without a catalyst. However, the addition of TiO2 particles in MW-UV system has increased the phenol degradation efficiency significantly. The extent of increase in degradation efficiency is dependent on the structural and optical characteristics of TiO2, which is affected by the TiO2 preparation method. In this work, the TiO2 nanoparticles with anatase structure were synthesized by hydrothermal (HT) and sol-gel (SG) methods. The synthesized materials were characterized using X-ray diffraction, FT-IR, thermogravimetric analysis, SEM, high resolution TEM and BET method. The higher degradation efficiency of 24% shown by MW-UV-TiO2 (HT) system in 120 minutes as compared to 20% shown by MW-UV-TiO2 (SG) system could be due to higher surface area and better textural properties of TiO2 prepared by hydrothermal treatment. The effect of various initial concentration of phenol (500-1500ppm) on degradation efficiency of MW-UV-TiO2 (HT) system revealed that the increase in the initial phenol concentration decreased the phenol degradation efficiency