Dried salted anchovy different processing methods: drying kinetics and modelling

Dried salted anchovy is processed with a combination of the salting and drying processes. Methods of salting and drying will determine the characteristics of the end product. The process of salting can be done by soaking (S) or boiling (B) in brine and drying can be done by mechanical drying (MD) or electric oven (OD). This study is aimed to determine the drying kinetics and mathematical models of dried salted anchovy processed with boiled salting and drying in the mechanical dryer (BMD), soaked salting and drying in the mechanical dryer (SMD) and boiled salting and drying in the oven (BOD). In the soaking treatment, fresh anchovy was soaked in 5% brine for 30 mins, while in boiling treatment, anchovy boiled in 5% brine for 10 mins. After the salting process was done, the anchovy was dried at 40°C for 3 hrs. The result has shown that BMD gives the highest drying constant. The page model is more suitable than other mathematical models because it has the highest R2 and the lowest SEE (Standard Error Estimates) value. The result of the effective diffusivity of BMD, SMD and BOD are 1.28067×10-10, 2.46685×10-10 , 1.80245×10-10. This research will contribute to the improvement of the drying and salting method to achieve a better quality of dried salted anchovies.

ESTIMATION OF INTERIOR TEMPERATURE OF AN ELECTRIC OVEN

This paper is aimed at estimating interior temperature of an electric oven with respect to the jacket temperature. A discrete dynamic model of first order difference equation is described for the system. Kalman filtering technique is applied to the discrete dynamic model for estimation of the interior temperature. A computer program is written to simulate the system. It was observed that the estimates of the interior temperatures are directly proportional to estimates of the Jacket temperatures with proportionality constant of 0.0009. With this method it is therefore possible to obtain the interior temperature of the electric oven at any given time.

STUDYING THE POSSIBILITY OF USING COLEMANIT TO OBTAIN ENAMELS ON STEEL

The practical use of boron and its compounds is extremely diverse due to its different properties. About 55 % of boron raw materials are consumed by the glass and ceramic industries for the manufacture of optical glasses, heat-insulating glass fibers, acid-resistant and refractory products, enamels, glazes, porcelain, etc. The paper considers the possibility of using colemanite to obtain enamel over steel. The optimal temperature-time regime of firing has been developed to obtain a high-quality coating and achieve the desired effect. It has been established that colemanite can partially replace cover enamel drill. On the basis of the studies carried out, it was found that the obtained experimental enamel is more refractory than the ESP-210 enamel. The optimal firing temperature for the experimental coating was established – 950 ° С, for the ESP-210 coating – 825 ° С. For uniform reflow of the experimental coating, a temperature is required that exceeds the reflow temperature of ESP-210 by 125 ° C. Colemanite-containing batch was cooked. Cooking was carried out in an electric oven at 1300 ° C for 5 hours. For further research, a slip was prepared from the experimental enamel and applied by pouring onto the plates

Performance of metakaolin based geopolymer concrete at elevated temperature

Due to the carbon dioxide emission arising from the production of cement, alternative concrete that is environmentally friendly such as metakaolin geopolymer concrete have been developed. However, the performance of metakaolin based geopolymer concrete (MKGC) when exposed to aggressive environment particularly elevated temperature has not been investigated. Therefore, this paper assessed the performance of MKGC exposed to elevated temperatures. MKGC cube specimens of grade 25 were produced using a mix ratio of 1:1.58:3.71.After preparing the specimens, they were placed in an electric oven at a temperature of 60oC for 24 hours. Thereafter, the specimens were stored in the laboratory at ambient temperature for 28 days. The specimens were then exposed to elevated temperatures of 200, 400, 600 and 800oC. After exposure to elevated temperatures, the MKGC specimens were subjected to compressive strength, water absorption and abrasion resistance tests. Results show that at 600 and 800oC, the MKGC lost a compressive strength of 59.69% and 71.71% respectively. Higher water absorption and lower abrasion resistance were also observed. Keywords: Cement, Compressive Strength, Metakaolin Concrete, Elevated Temperature.

The Effect of Different Cooking Methods on The Nutritional Composition f Tilapia (Oreochromis Sp.)

Tilapia (Oreochromis sp.) is a fish that is gaining ground in cultivation and sales because of its nutritional properties: high protein content, vitamins, and minerals with few unhealthy saturated fats as in red meats. This work aimed to evaluate the effect of cooking on the chemical composition, Aw, and pH, in addition to the electrophoretic, and fatty acid profile of the Tilapia using an electric oven, microwave and steaming as cooking methods. The results showed that the nutritional components of Tilapia changed significantly (p<0.05) at two temperatures and at two potencies used. Microwave and steaming preserved better the proteins in the Tilapia after its cooking. Electrophoresis results showed a decrease in intensity and number of bands depending on the type of treatment to which the meat was subjected. On the other hand, the electric oven method at 2 temperatures resulted with the highest increase in essential fatty acids (45% and 36%), with a slight decrease in the ω-6 family, because of a probable hydrolysis or oxidation of the same. The steam cooking showed a slight increase in essential fatty acids, but microwave oven preserved better the proteins, indicating that this could be a good method for cooking Tilapia.

8. Decarbonizing heat and transport

‘Decarbonizing heat and transport’ describes methods for decarbonizing heat and transport. Using renewable electricity directly to produce heat, as in an electric oven, is currently more expensive than burning gas, or other fossil fuels, to generate heat. Capturing the carbon dioxide emissions from existing industrial processes is difficult, and the chapter addresses the challenges of meeting the large heat demand with renewable electricity, particularly for industrial processes that require high temperatures, such as in the manufacture of steel and cement. There, using electricity to produce combustible fuels (power-to-gas), such as hydrogen, could be effective. For heating buildings, electrically driven heat pumps are promising. Transportation also presents challenges. While the performance of electric cars is good, currently the main hurdle to switching is their cost. However, battery costs are falling fast, and new and traditional car manufacturers are already investing a considerable amount of money in developing electric cars. For heavy transport, fuel cells and power from ammonia are being considered.

Comparative analysis of drying coffee beans using microwave and conventional oven

This article reports a comparative study of experimental results obtained during the drying of Castilla-variety coffee beans from Santander, Colombia. They were performed by two means: thermal and electromagnetic radiation. Twenty experiments were carried out, ten tests in a microwave cavity at 2,450 MHz-1,080W, and ten tests using a conventional electric oven with temperature controlled at 50±2oC. Experiments were made using samples of coffee beans with parchment, without parchment, and of the only-parchment. For each sample, dimensionless moisture ratio and diffusion coefficients were determined, according to the second law of Fick. We found that the diffusion coefficient of the samples dried in a microwave cavity was twenty-two times higher than the diffusion coefficient of samples dried with thermal radiation. Likewise, it was observed that samples in conventional oven showed a uniform temperature, in contrast with those heated by microwave radiation. Such results are useful for designing hybrid systems for drying coffee beans.