Optimization of process variables for ohmic heating (OH) of fish steaks was done by response surface methodology according to Box–Behnken design. The low and high levels of the variables were 3 and 7 min for processing time; 55 and 75 V for applied voltage and 10 and 15 mm for product thickness. Responses studied comprised colour, temperature, hardness, water activity and organoleptic score. It was found that effects of time and applied voltage were significant on all responses. Optimum conditions (desirability = 0.820) obtained by numerical optimization were processing time, 5.75 min; voltage, 75 V and product thickness, 14.4 mm to achieve maximum colour variation, temperature and organoleptic score and lower hardness and water activity. Corresponding to the optimum conditions, the predicted value for temperature was 71.88°C, colour 49.85, hardness 1.125 kg, water activity 0.772 and overall acceptability 7.891.

The currently available technology of Makhana processing is not only indigenous and manual but also cumbersome and painstaking. The process involves handling of hot roasted seeds which require two to three laborers to process 8-9 kg of popped Makhana per day. With the view to mechanize the unit operation involved in Makhana processing, grading and roasting machine were designed and developed. Grader was developed based on engineering properties of Makhana while the roaster was designed based on preliminary experiments for Makhana, i.e. shell breaking force at different temperatures and for varying residence time. The grader performed best at feed rate of 20 kg/h with grading effectiveness of 0.99, 0.955 and 0.95 for grade 1, grade 2 and grade 3 Makhana seeds respectively. The developed roasting machine worked satisfactorily with 100% popping efficiency at machine capacity around 23.0 kg/h. The residence time of seeds in the roaster was 2.6 min and the average temperature of roasted seeds of grade 1, grade 2, grade 3 was found to be 271.33°C, 281.1°C and 280.7°C respectively.

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Early 2020 witnessed the emergence of global agrarian crisis with the widespread burgeoning of destructive migratory pest, Desert Locust (Schistocerca gregaria) in East Africa, Southwest Asia, Pakistan and India. Characterised by the ability to eat ravenously, breed exponentially and migrate rapidly; locust swarms has led to substantial agrarian disaster. The current official strategy is to control the upsurges to evade plague. Though it may seem attractive and efficient, it is sensible only if the numbers are relatively low. The socio-economic and environmental challenges posed by the unprecedented locust outbreak has prompt the scientists worldwide to emanate an effective preventive management strategies that rely on updated knowledge of pest biology, ecology and behaviour along with efficient monitoring, data management, analysis, forecasting, resource deployment and control techniques. In addition, the integrated network of field teams, decision makers, analysts, rural governing bodies and farmers potentially offers better compliance of pest management strategies.