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Pulse-Electric Field (PEF) System can be described as a system that utilises high voltages applied at a specific interval and with a particular wave shape in treatment (inactivation and destruction of micro-organism cells) of liquid or solid food. Pulse-Electric Field food processing system reduces the drawbacks (such as deterioration in sensory values, energy contents, and freshness) of other methods significantly. To generate the high voltage needed for the treatment, a series of capacitors and diodes connected were used. Generation of the desired pulse shape, which is the square wave is achieved through ATmega-328 microcontroller. The pulse control system is made up of a button to vary the treatment time, the power switch and a 16x2 alphanumeric Liquid Crystal Display (LCD) which serves as visual feedback. For the evaluation of the fabricated system, bacteria were cultured using MacConkey agar solution and then diluted in orange juice which serves as samples of liquid food. From the samples prepared, the bacteria count is in order of 1.61x10 5 CFU/mL before treatment, after treatment the count reduced to 1.01 x10 5 CFU/mL and 2.10 x10 4 CFU/mL concerning 1kHz and 2kHz pulse frequency used for the two samples treated.

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Introduction: Cowpea decorticating is a crucial post-harvest process that involves removing the seed coats from the kernels to produce ready-to-use cowpea products such as flour, grits, and protein concentrates and food products such as Akara and Moinmoin in south western Nigeria. Methodology:  In this study, a locally developed cowpea decorticator was tested and evaluated using small oloka (a Nigerian local cowpea breed) cowpea grains. The machine was allowed to run empty for five minutes before the experiment commenced. Three samples of 1kg each were weighed and wetted with same quantity of water for 10, 20, and 30 minutes, respectively. The samples were then fed into the developed decorticator running at a speed of 420 rpm, and the operating speed and time taken were determined using a digital tachometer and stop watch, respectively. Samples of decorticated, undecorticated, and broken cowpea were collected and weighed to evaluate the efficiency of the machine based on the decorticating length and wetting time of cowpea grains. Results: The study revealed that as the decorticating length increased from 44.5 to 178 mm and wetting time increased from 10 to 30 minutes, the decorticating efficiency increased from 55 to 92.1%. The highest average decorticating efficiency of 92.1% was obtained at 178 mm decorticating length and 30 minutes wetting time. Conclusion: These findings showed that the decorticating efficiency of the machine depends on the wetting time and the decorticating length of the machine.

The lethargic modes of medical waste disposal in many developing countries have been a cause of concern to many regulatory agencies. In this study, effect of reactor temperature on pyrolysis of lignocellulosic medical waste in a fixed bed reactor was investigated. Gauze bandage was procured from AKOL Pharmacy, Ogbomoso, South-Western Nigeria. Samples of the gauze bandage, 40 g each at a time, were fed into a retort and the retort inserted into a developed fixed bed reactor for pyrolysis at different temperatures (300, 400, 500 and 600 o C) with a residence time of 15 minutes. Tar, gas and char yields were weighed using an electronic balance (WT20002T, RS232C) and were further expressed in percentage of the initial weight of the sample. Results showed that tar and gas yields increased with increasing reactor temperature while char yield decreased with it. Both intraand extra-particle secondary reactions were insignificant and therefore could not influence the yield spectra of products. The highest yield of tar, gas and char were 52.08, 28.42 and 52.7%, respectively while the lowest yield were respectively 30.50, 16.80 and 19.50%. Lignocellulosic medical waste can be a viable source of biofuels and raw materials respectively for sustainable development and for chemical industries.