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Direct energy utilization in the processing of cocoa beans into powder in some cocoa processing factories located in South-western Nigeria was investigated. Energy utilization was evaluated for the eight major unit operations that cocoa processing entails, considering energy supply from the national grid and diesel. The data obtained were imputed into existing energy equations to estimate the energy utilized during each unit operation. The results show that the total energy requirements for the processing of raw cocoa bean into powder are 2.23 and 2.38 MJ kg-1 using energy from the national grid and diesel, respectively. The most energy-intensive operation identified are pressing and milling; which account for 58% and 26.3% of the total energy utilized. For all the unit operations involved in the processing of cocoa bean into powder, diesel engine generator as a power source consumed more energy than that of the national grid. From material balance, an average of 7.2 metric tonnes of cocoa beans yields 2825 kg of cocoa powder and 2925 kg of cocoa butter with about 20.14% weight loss along processing line. This work provides important data for energy generation, planning, utilization and cost in the processing of cocoa beans into powder. [ABSTRACT FROM AUTHOR]

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 (p<0.05). Large and medium roasted nuts exhibited the highest whole kernels out-turn (99.6% and 99.5% respectively). Raw nuts gave the least values of whole kernels out-turn (62%, 33.9%, and 44.7% for large, medium and small respectively). Pre- shelling treatment made cashew nuts more amenable to fracture; but the whole kernels out-turn of large nuts was generally higher than that of medium and small nuts. The pre-treatments showed no significant difference in the chemical composition and energy content of cashew kernels; but for crude fiber and carbohydrates wherein the differences were significant (p<0.05). [ABSTRACT FROM AUTHOR]

There is an increasing worldwide interest in the effective utilisation of municipal solid wastes as an avenue of reducing its high cost of clearing. Municipal solid wastes are usefully converted into a medium grade fuel (biogas) to reduce its nuisance value to the environment. In this paper, the potential of vegetable (putriscible) component of municipal solid wastes was examined in terms of biogas production. The vegetable component of the waste was used as substrate in a batch-fed 200 dm³ capacity anaerobic digester, which was consecutively loaded with a 10-20 kg ranged weight of vegetable. The total solid (TS) of substrate was 8-10% over a retention period of 40 days. The temperature of the substrate during bio-digestion was maintained within 29°C and 33°C. The average biogas yield varied from 5.15 dm³/kgTS to 5.83 dm³/kgTS. From the digestion experiments, a regression equation, called the municipal solid wastes energy value model, was derived. This model estimates the biogas production from municipal solid wastes. For the predictive model formulation, a relationship between retention time and the daily/total biogas yield was explored. The polynomial function significantly represents the models formulated for the different quantity of substrate loaded. This strongly suggests that the polynomial series is best suited to predict the relationship between retention time and the quantity of substrate loaded for the experiment. This tool is useful in optimising biogas production from energy materials, and requires further validation and refinement. Hopefully, this study advances this increasingly growing area of municipal solid wastes research. [ABSTRACT FROM AUTHOR]

This study assessed some fabricators’ technical know-how in the production or fabrication of machines used for the production of special palm oil (SPO). The study also examined facilities possessed by the fabricator 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 analyzed with the Statistical Package for the Social Sciences (SPSS). Descriptive statistics such as frequency distribution and mean were used to summarize 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 $718.01 and $658.18 respectively. There was a highly 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 SPO. [ABSTRACT FROM AUTHOR]

Oil point pressure of sheanut kernel was determined under different pre-processing conditions of moisture content, heating temperature, heating time and particle size. Results show that the pressure decreased as moisture content increased from 4% to 6%, and thereafter, increased with further increase in moisture content. It equally decreased with increase in temperature and heating time. Highest oil point pressure value was 2.6389 MPa for coarse kernel particles at 4% moisture content heated at 50oC for 5 min, and 1.5554 MPa for fine particles at 10% moisture content heated at 50°C for 5 min. Lowest value for coarse and fine kernel particles was 0.929 MPa and 0.6380 MPa respectively and this was obtained at the conditions of 6% moisture content, 100°C and 15 min heating time. Analysis of Variance (ANOVA) showed that all the pre-processing variables and their interactions significantly affected the oil point pressure of at 1% level of significance. This was confirmed using response surface methodology. Multiple regression analysis yielded equations that expressed oil point pressure as a function of kernel moisture content, heating temperature and heating time. The models yielded coefficients that enabled oil point pressure of the kernel to be predicted with high coefficient of determination. [ABSTRACT FROM AUTHOR]