A solar drying system designed on the principles of convective heat flow, constructed from local materials was employed in drying yam (Dioscorea Alata). A glass collector having an efficiency of about 0.63 was used along with an absorber for absorbing the heat energy. The drying chamber consisted of drying trays. A chimney fitted at the top centre of the drying chamber enhanced airflow. Air passing through the collector heated up and dried the foodstuff in the drying chamber. The latitude of Ilorin is 8.26oN and the collector angle could be varied . 56o C, 41o C and 71o C were obtained as the maximum attainable temperatures for the drying chamber, ambient and collector respectively. Two samples of yam chips, each weighing 1560g and having an average size of 1cm thick, were dried both inside the dryer and outside the dryer within its surrounding. The initial moisture content of the yam was 70.3% (wet basis) and its final moisture content was 9% (wet basis).The result was compared to natural sun drying. It was observed that the drying time was reduced from 52 hours for sun drying to 45 hours for solar drying. The total cost of the construction was 6, 105 Naira.

Insolation available to dry crop on any clear-day was mathematically simulated on a local computer, using a suitable object oriented programming language (JAVA), for predicting solar radiation available at any given time in the Northern hemisphere on longitude East on Greenwich. Uyo, AkwaIbom State, Nigeria was used as a case study. The deterministic model was developed using set of equations and taking into consideration the factors of two components of solar radiation: The beam and diffused components. The results of the model rapidly produced hourly, monthly and daily data of insolation on horizontal earth surface and was verified and validated using existing solar radiation data, gotten from the Nigeria Metrological Station, Department of Geography and Regional Planning, University of Uyo, Nigeria. Predicted results showed that total solar radiation on any clear-day of the year in Uyo, Nigeria is sufficient to dry crops provided the crops are dried between the hours of 9a.m. and 4 p.m. March, April and September were found to be the best months for crop drying, while August and December recorded the lowest solar insolation.

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A survey was carried out in all the twenty three (23) Local Government Areas of Rivers State to evaluate the different methods of fish preservation in the State. The required information was collected by the use of questionnaires and direct interviews with the fish farmers and traders. The study holds that gender difference influenced approach to fish business, and that respondents are faced with problems which include lack of record keeping and finance. Others are inability of the State Government to introduce modern methods of fish processing/preservation techniques and proper management of fish business. If these innovations are introduced to farmers, there will be improvement in production, curtail spoilage and boost fish preservation in Rivers State.

This report presents a comprehensive review of the effects of tea particle size (PS), dipping temperature, infusion time, dipping frequency, and effect of permeance on tea infusion focusing on zobo (Roselle – Hibiscus sabdariffa) tea. Tea production process follows a series of unit operations depending on the type of tea being produced. Various forms of tea are scented, white, oolong, green, and black teas. Generally, the basic unit operation involves include withering, maceration, fermentation, fixation, rolling or shaping, drying, and curing or aging of the tea leaves. Before drinking, the processed tea is prepared by infusing the tea leaves in hot or cold water with or without tea bags. For maximum extraction of bioactive compounds which are responsible for the high nutritive and functional properties of tea, it is important to understand tea infusion process and factors affecting the infusion kinetics (IK). PS and distribution of food powders, their measurements, and their instrumentations are displayed as well as the undesirable phenomena in food powders. Tea packages and tea bag selections, the effect of different factors in tea IK, novel technology for tea production, and future prospects of tea production are also discussed. This review aims at providing information for the understanding of tea PS and factors affecting tea IK thereby enhancing the understanding of different principles behind tea infusion; a perspective on zobo production.