Effect of different thawing methods on quality properties of stuffed pasta (manti)

Stuffed pasta or ‘manti’ is a traditional food consumed fondly in Turkey. For consumption, it is produced as fresh, frozen or dried manti. Frozen manti is cooked directly without thawing. The present study investigated the effects of different thawing processes on physicochemical properties and sensory qualities of frozen stuffed pasta (manti). The following five thawing processes were used individually: (1) infrared, (2) microwave (3) infrared-assisted microwave, (4) dry hot air and (5) running water thawing. The storing temperatures of manti found in the market were 10°C and 24.5°C. Consequently, manti samples were thawed up to these temperatures. It was determined that the shortest thawing period (20 sec) was that of infrared-assisted microwave process. The longest process was dry hot-air thawing (420 sec) in manti samples that were thawed until refrigerator (+4°C) and room temperatures (24.5°C). Thawing methods did not change pH, moisture values and weight gain (p > 0.05). It was found that sensory qualities and amount of dry matter passing into the water of samples were different (p < 0.05). It was concluded that thawing was necessary for frozen manti, and the best method was microwave thawing.

Optimized Degradation of Bisphenol A by UV/H2O2 coupled to Microwaves in a Novel Reactional Setup

In this paper, the UV/H2O2/MW (microwave) process was compared with the UV/H2O2 one, using bisphenol A (BPA) as a model-pollutant. The proposed experimental setup was operated in batch recycle mode and allows for the direct comparison among different processes: UV only, H2O2 only, MW only, UV/H2O2, UV/MW, H2O2/MW, and UV/H2O2/MW, as well as temperature control to minimize thermal effects. The degradation of BPA at near-environmental concentration (100 µg L−1) was optimized by an experimental design approach (Response Surface Methodology) and its residual concentration was measured by HPLC. Approximately 95% of the initial BPA amount could be removed in 30 min at the optimal conditions (CH2O2 = 20 mg L−1, flow rate = 700 mL min−1, and MW power = 245 W). The experiments designed for comparing the UV/H2O2 and the UV/H2O2/MW processes showed that the use of MW doubled the initial pseudo-first-order degradation rate (from 0.046 to 0.10 min−1) and significantly increased the maximum oxidation capacity of the system (from 86 to 100%). Although the reasons behind those results are still unclear, it seems that the existence of non-thermal effects of the MW irradiation should be considered.

Synthesis and Characterization of Graphene Prepared from Rice Husk by a Simple Microwave Process

Graphene can be prepared by many methods; a simple microwave process is used in this study. The objective of this research paper is to find the best root for preparing the graphene from rice husk with the help of microwave process. In this work the Carbon source catalyst and microwave oven is used to prepare graphene. Zeta Sizer, FTIR, UV-Vis, XRD, FESEM and EDX were utilized to characterize the prepared graphene. To find the best combination of input variables that effect the crystallite size of the particle as an output variable Taguchi L9 array used. The average crystallite size 58. 01nm comes from characterization. The presence of graphene in the prepare particles is confirmed by XRD and from EDX, and FTIR.

An ultra-effective pathway for fully removing the oxygen components of graphene oxide by a flame-assisted microwave process

An ultra-effective and reliable pathway to reduce GO into graphene by an about 4 seconds flame-assisted microwave process.

Hybrid microwave with heat recovery for an efficient drying process

Microwave technology has come a long way from the sixties when the first microwave ovens were developed. This first generation of microwave ovens uses only microwaves to heat the substrate and with an efficiency of around 63% in converting electrical energy to microwaves, this means 37% of the electric energy is lost as heat. The first improvement to this system “second generation” is using hybrid heating with both microwaves and hot air. The hot air in this case is simply the air used to cool the magnetron and transformers that is blown into the microwave cavity. The 37% of lost energy can thus be reused. The first role of the hot air current is to remove moisture from the cavity to avoid condensation on the (cold) cavity walls. The second role is to insulate the hot product from the cold environment and prevent energy loss. The third role is increasing evaporation speed; this decreases drying time and can also keep the drying temperature low through evaporative cooling. Low drying temperatures are favored in many processes especially with food as it delivers a superior dry product.The “third generation” utilizes an additional heat exchange to further increase the system’s efficiency. The hot (wet) exhaust air is not fully saturated yet so it can be used to preheat the substrate before it enters the microwave cavity. A good example is thawing and preheating frozen starting material. If water cooled magnetrons are used, the hot air is replaced by hot water instead for the heat exchange. Microwave processes are generally much faster resulting in smaller machines and reduced operational area. When designing a microwave process all these factors need to be taken into account to result in the cheapest and most robust process. As heat exchange generally takes a long time, it should only be done to a degree that it does not slow down the microwave process.

Mechanical and Barrier Properties of PVP-Carbon Dot Nanocomposite Films

This research reported carbon dot were synthesized form citric acid and urea through a single step microwave process and Poly Vinyl Pirrolidone (PVP) films composited by carbon dot were prepared. The effects of different composition carbon dots on mechanical strength of films and water vapour barrier were evaluated. Highest mechanical yielded composite film were analyzed their thermal stability. Average of carbon dot diameter was found 90.61 nm and polydispersity indice 0.396. Different composition carbon dot exhibit significant improvement in tensile strength and modulus. Water permeablity of films varieate with content of carbon dot. The presence of carbon dot had a negligible effect on Tg of film and show melting process.

Controllable synthesis of barnyardgrass-like CuO/Cu2O heterostructure nanowires for highly sensitive non-enzymatic glucose sensors

Barnyardgrass-like CuO/Cu2O heterostructure nanowires were rationally constructed via a synergistic approach integrating precipitation and microwave process based on porous Cu(OH)2 nanorods and exhibit commendable glucose detection capacity.