Crackability and chemical composition of pre-treated cashew nuts using a hand-operated knife cutter

The crackability and chemical composition of pre-treated cashew nuts were investigated considering three nut grades (large, medium and small) and two methods of pre-shelling treatment (hot-oil roasting and steam–boiling).  The pre-treated nuts were shelled using a hand operated knife cutter.  Crackability was calculated as a ratio of the weight of completely shelled nuts to the total weight of nuts fed into the machine.  Whole kernels out-turn was calculated as the ratio of the weight of whole kernels to the total weight of kernels recovered after shelling.  Chemical analyses were carried out following standard methods in literatures.  The average values of crackability for raw, roasted and steam-boiled nuts were 76%, 100% and 99% respectively.  For roasted nuts, crackability was higher than that of steam-boiled nuts and pre-shelling treatments affected whole kernels out-turn significantly (

A motorized device for cracking pre-treated dika nuts

Cracking of dika nut has presented serious challenges to local processors considering the arduous task it constitutes during processing.  A motorized machine that is capable of multiple cracking of dika nuts was designed, fabricated and tested. The major components of the machine include a sliding hammer, a gear unit, a chain conveyor and cracking trays.  The experimental machine was evaluated on the basis of cracking efficiency and throughput considering three types of pre-treated nuts (sun-dried, oven-dried and roasted) and two nut sizes (small and big).  The cracking efficiency and throughput were: 65% and 8.84kg/h, 63% and 7.75kg/h, 45% and 5.67 kg/h for roasted, oven-dried and sun-dried small nuts; while the corresponding values for big nuts were: 72% and 12.86kg/h, 70% and 12.58kg/h, 67% and 12.41 kg/h, respectively.  Big dika nuts indicated a higher cracking efficiency and throughput than small nuts. The highest cracking efficiency and throughput values (72% and 12.86 kg/h, respectively) were obtained for big roasted nuts.  The method of pre-treatment and dika nut sizes were found to affect the cracking efficiency and throughput of the motorized dika nut cracking machine.  With a throughput of 10 kg/h and the possibility of cracking twenty nuts at a time, this machine is an improvement over existing designs.  A machine of this nature will be suitable for small and medium scale applications in the processing of dika nut

Energy Requirements in the Processing of Cocoa Beans into Powder

This paper aims to analyse the direct energy utilization in the processing of cocoa beans into powder using energy from the national grid and diesel engine in some cocoa processing factories located in South-western Nigeria. Energy consumption in the processing of cocoa beans into powder was evaluated for the eight major unit operations that cocoa processing entails, namely: cleaning, roasting, winnowing, milling, alkalizing, pressing, butter packing and grinding/sieving. The data obtained were imputed into existing energy equation to estimate the energy requirement for each of the eight unit operations. The results show that total energy expenditure in the processing of raw cocoa bean into powder were 1.815 and 2.384 MJ/Kg using national grid (PHCN) and diesel engine, respectively. The most energy‐intensive operation identified were pressing and milling accounting for 58 % and 26.3 % of the total electrical energy expenditure. For all the unit operations involved in the processing of cocoa bean into powder, diesel engine generator consumed more energy than the PHCN sourced power. From material balance 7200 kg of cocoa beans will yield about 2825 kg of cocoa powder and 2925 kg of cocoa butter with about 20.14% weight loss in the processing line. This work provides important data for production planning, process optimization and reduction in energy costs in cocoa processing.

Pre-shelling parameters and conditions that influence the whole kernel out-turn of steam-boiled cashew nuts

This work investigates the effect of moisture content (MC), nut size distribution and steam exposure time (SET) on the whole kernel out turn (WKO) of cashew nuts during shelling using a 3 x 5 x 4 factorial experiment. Three nut sizes: small (18–22 mm), medium (23–25 mm) and large (26–35 mm); five levels of MC: 8.34%, 11.80%, 12.57%, 15.40%, 16.84% (wet basis) and four levels of steam exposure time (SET): 28, 30, 32, and 34 min were considered. Nuts were conditioned with warm water to the desired moisture content of 8.34%,11.80%, 12.57%, 15.40% and 16.84% (wb); and steam-boiled at 700 kPa for 28, 30,32, and 34 min. The pre-treated nuts were shelled using a hand-operated cashew nuts shelling machine. The results showed that the single effect of MC, steam exposure time (SET) or nut size distribution is not enough for estimating WKO; it is rather by an interaction of these parameters. The optimum WKO of steam-boiled nuts was 91.74%, 90.94% and 87.98% for large, medium and small sized nuts at MC∗SET combination of 8.34%∗30 min, 11.80%∗32 min and 8.34%∗30 min, respectively. Pre-treatment of cashew nuts by steam boiling was found to improve whole kernel out-turn of the cashew nut. Whole kernel out-turn decreased as MC increased, thereby limiting the need for moisture adjustment when nuts are to be processed by steam boiling

The Agricultural Engineer: His Training for Agricultural Transformation in Nigeria

This paper is an appraisal of Agricultural Engineering education in the quest for manpower to drive the agricultural transformation agenda in Nigeria. It takes a critical look at Agricultural Engineering training especially in Nigerian Universities, focusing on curriculum changes, institutional capacity for manpower development and training, succession plan and post graduate training vis-à-vis modern trends around the world. Among twenty seven (27) institutions presently offering Agricultural Engineering in Nigeria, ten (10) were established after year 2000 and do not have post graduate training program. The survey show that 31.6, 28.7, 11.8 and 27.9% of the academic staff are in the area of farm power and machinery, crop processing and storage, farm structures and environment and soil and water conservation engineering, respectively. About 66% of academic staff members in Nigerian Universities are in the status of Senior Lecturers and above. Given Nigeria’s vast agricultural resources and as she continues to attract global attention in the African food crisis, this paper advocates the proper inclusion of Agricultural Engineers as key role players in all tiers of governance and levels of policy formulation to drive the agricultural transformation agenda

Thin layer drying characteristics of alligator pepper, ginger and turmeric

The delightful pungency, aromatic compounds and phytochemicals in some spices make them indispensable in local food systems and native medicine, hence, driving a robust market in many parts of the world. The understanding of their drying characteristics is very important for processing and adding value, and a thin layer drying study is a proven method for achieving this. In this study, changes in the moisture content, moisture ratio, drying rate and effective diffusivity of alligator peppers, ginger and turmeric were investigated at three drying temperatures 50, 60, and 70 °C following standard procedures. Five models were proposed to simulate the drying process. Non-linear regression was used to establish the coefficient of determination (R2), sum of square error (SSE) and root mean square error (RMSE) for each model to determine the model of the best fit. The Page model gave the best fit for ginger while the logarithmic model was best fitted for alligator peppers and turmeric. The effective diffusivity ranged from 1.79-3.08 × 10-9, 8.44-9.74 × 10-9, and 4.06-6.49 × 10-9 m2.s-1 for alligator peppers, ginger and turmeric, respectively. The activation energy ranged from 16.5-22 kJ.mol-1.K-1 for the three spices. These findings promise improvement in the drying, processing and handling of spices, thereby boosting the obtainable income from the value chain

Development of a Multipurpose Small Scale Dryer for Agricultural Products

A multipurpose cabinet dryer was designed, constructed and tested using locally available materials. The system comprises a heating chamber, heat exchanger, drying trays, 3-phase blower, three heating elements of 1800 W each, and a control box, which consists of temperature control, contactor, thermocouple, and circuit breaker. The dryer was evaluated based on power consumed, moisture removal, drying rate, and drying efficiency. The result showed that the energy consumed when drying plantain chips, moringa leaves, okra, and locust beans are 346.55, 55.92, 110.63 and 49.64 kJ, respectively. The energy consumed increased with an increase in the moisture removed and drying time. Similarly, the drying rate for plantain chips, moringa leaves, okra, and locust beans was 0.58, 0.09, 0.18, and 0.10 g/min, respectively, which depended on the initial moisture content of the product and the air velocity. The drying efficiency ranged between 62.1 and 65.5%, it reduced with an increase in the amount of moisture removed and the drying temperature. For the products with which the dryer was tested, the drying system promises satisfactory performance for small scale applications

Technological Capability of Local Fabricators in Fabrication of Equipment for Special Palm Oil in Nigeria

This study assessed some fabricators’ technical knowhow in the production or fabrication of machines used for the production of Special Palm Oil (SPO). The study also examined facilities possessed by the fabricators   with the aim to providing intervention that would abridge the widening demand gap between the demand and supply of SPO for domestic and industrial applications. Multistage sampling technique was used to select 98 fabricators as respondents across four geopolitical zones where palm oil is produced in Nigeria.  A well-structured questionnaire and an observant check list were used to collect data relevant to the objectives of the study from the respondents. The collected data were collated with Epidata application and analysed with the Statistical Package for the Social Sciences (SPSS). Descriptive statistics  such as  frequency distribution and mean were used to summarised the data while inferential statistics such as  Chi-Square  and  multiple regression were used to make deductions. Findings of the study showed that   majority  of the respondents were  within the age of  bracket of 40 and 49  and had West African Examination Certificate or its equivalent as major educational qualification./ Average income generated per year based on their primary occupation and other occupation were ₦300,000 and ₦275,,000  respectively. There was a great significant relationship between membership of organization and the information received at p = 0.05 probability level. Majority of the respondents said they learned the art of fabrication informally from someone. They had limited and dysfunction number pieces of equipment for bending, rolling and lathing, which hindered, the fabrication of machines involved in the production of special palm oil (SPO)