Palm Kernels Research Articles

Development and Assessment of Cracking and Sorting Processes of Palm Kernel Nut Machine

This paper presents a research on the Development and Assessment of the cracking and sorting processes of palm kernels nuts in a mechanical cracking machine. The palm kernel oil is an important agricultural produce, it has a wide range of usage aside from cooking. In attempt to reduce energy exploitation, in conjunction with the regular high rate of demand for products been extracted from palm kernel nut, the need to improve on the manual method of cracking and sorting became eminent. The mechanical cracker was made up of two units: the cracking and sorting unit. Experimental studies of properties of machine components were considered with the purpose of avoiding fatigue failure and fracture on the palm nuts during the processing duration. The mechanical cracker was designed, fabricated and performance evaluation carried out using locally sourced materials. It was developed with a 5hp electric motor to drive the machine coupled with belts and pulleys. The average data assessment shows a 2.01% of un-cracked nuts, 2.36% of partially cracked nuts, 93.58% of un-cracked nut and 2.05% broken nuts. The cracking-sorting efficiency was estimated at 94% and throughput capacity was determined to be 80kg/h while the overall palm kernel recovery efficiency was 85%. These suggest that the machine is very suitable for separating the palm kernel nuts from the cracked shells clearly and completely.

Development and Assessment of Cracking and Sorting Processes of Palm Kernel Nut Machine

This paper presents a research on the Development and Assessment of the cracking and sorting processes of palm kernels nuts in a mechanical cracking machine. The palm kernel oil is an important agricultural produce, it has a wide range of usage aside from cooking. In attempt to reduce energy exploitation, in conjunction with the regular high rate of demand for products been extracted from palm kernel nut, the need to improve on the manual method of cracking and sorting became eminent. The mechanical cracker was made up of two units: the cracking and sorting unit. Experimental studies of properties of machine components were considered with the purpose of avoiding fatigue failure and fracture on the palm nuts during the processing duration. The mechanical cracker was designed, fabricated and performance evaluation carried out using locally sourced materials. It was developed with a 5hp electric motor to drive the machine coupled with belts and pulleys. The average data assessment shows a 2.01% of un-cracked nuts, 2.36% of partially cracked nuts, 93.58% of un-cracked nut and 2.05% broken nuts. The cracking-sorting efficiency was estimated at 94% and throughput capacity was determined to be 80kg/h while the overall palm kernel recovery efficiency was 85%. These suggest that the machine is very suitable for separating the palm kernel nuts from the cracked shells clearly and completely.

Study on the Effects of Physical Properties of Tenera Palm Kernel during Drying and Its Moisture Sorption Isotherms

A study on the effect of the physical properties and moisture sorption isotherm of palm kernels constitutes the critical criteria in evaluating the drying performance. The drying was evaluated as a function of moisture content (MC) in the range of 0.31–0.02 kg/kg (d.b.). Whereas, the equilibrium moisture content (EMC) of palm kernels (whole kernel and ground kernel) was determined experimentally using the standard gravimetric method at different temperatures (50 °C to 80 °C), over a range of relative humidity (RH) from 10% to 81%. Palm kernel length, width, and thickness decrease from 16.08 ± 2.09 mm to 14.17 ± 2.30 mm, 12.06 ± 1.40 mm to 11.24 ± 1.08 mm, and 10.01 ± 1.27 mm to 9.18 ± 1.04 mm, respectively, when MC decreased. Bulk density, surface area, and specific surface area decreased as the MC decreased, while porosity and true density were increased. EMC of palm kernels (whole kernel and ground kernel) decreased with an increase in temperature at constant RH. Modified Oswin and modified Halsey models were found to be the best for predicting desorption moisture isotherms for whole and ground palm kernel, respectively. Therefore, the study of the effect of drying on physical aspects as well as moisture sorption isotherms is important to further analyze the drying performance of Tenera palm kernel (e.g., equipment design and energy requirement).

Sebaran Kualitas Air Teluk Pamukan

Teluk Pamukan is the closest fishing ground used by fishermen who live on the coast of Teluk Pamukan. Apart from fisheries, several other activities in the Teluk Pamukan area include industrial shipping or coal transportation traffic using barges, transportation of crude palm oil (CPO), and is an area for loading and unloading fertilizers and oil palm kernels by tankers. This activity has led to allegations of disturbance in the aquatic ecosystem in the form of a decrease in water quality, particularly in fishing areas. The decrease in water quality will certainly affect the status of water quality that is no longer by its designation so that it can cause social problems in the community. The purpose of this research was to identify the general characteristics of Teluk Pamukan, map the distribution patterns of water quality and the scale of water quality in Teluk Pamukan, and to analyze fishermen's perceptions of the decline in water quality. The sampling location was in the waters of Teluk Pamukan. The method used to determine the status of water quality was the Pollutant Index according to the opinion of Sumitomo and Nemerow (1970). The results obtained can be concluded that the environmental quality scale for each parameter varied from very bad to very good. However, the results of the pollutant index calculation at all stations were included in the Moderately Polluted category

Latvia-South Africa Economic Relations 1918–1940

The Republic of South Africa was the first country on the continent of Africa to recognise the renewed independence of the Republic of Latvia on 29 August 1991. This paper provides an overview of Latvian-South African economic relations in the interwar period. In the interwar period Latvian and South African economic relations were mainly confined to foreign trade. Latvia’s foreign trade in relation to South Africa (then known as the Union of South Africa) was more or less regulated by Latvia’s 1923 treaty with Great Britain. Latvia’s main imports from South Africa in the interwar period were fruits (including oranges, mandarins, apricots, grapes, pears, etc.), tanning extracts and materials, paint and varnish extracts and materials, raw wool, palm kernels and oil, and furs and hides, whilst Latvia’s main exports to South Africa were fish and fish conserves (including “Sprotes”), confectionery and chocolates, timber and timber products, paper and paper products, plywood, and liquors etc. In general, despite a growth in trade in the 1930s, trade and thus economic relations were of marginal significance to both countries in the interwar period.

Activated Carbons from Palm Kernels Shells Prepared by Physical and Chemical Activation for Copper Removal from Aqueous Solution

Preparation and evaluation of activated carbon from the palm kernel shell (PKS), an abundant agricultural residue, by physical and chemical activation were carried out. The activation treatment of adsorbent with and without chemicals modification was evaluated. The physical activation using nitrogen gas and chemical treatment using 10 wt.% of sodium hydroxide and nitrogen gas as the activating agent. This study evaluated the activation temperature and nitrogen gas rate. The results showed that activated carbon treated with NaOH followed by heating under nitrogen gas had the highest iodine number of 1062.8 mg/g and methylene-blue number of 247.2 mg/g (heating at 750 °C, nitrogen gas flow rate of 100 mL/min). The equilibrium data obtained at various initial concentration reasonably fit well with the Langmuir adsorption isotherm. The adsorption of Cu(II) ions fit with the Langmuir isotherm pattern with adsorption capacity (Xm) of 8.9445 mg/g and kf value of 0.16802 L/mg for activated carbon without NaOH treatment. The adsorption capacity of activated carbon with NaOH and heating at 750 °C under nitrogen gas was obtained 12.0773 mg/g and kf value of 0.15076 L/mg. Those results suggested the prepared adsorbent could be considered as a promising candidate for Cu(II) ions for wastewater treatment.

Proposing blends for improving the cold flow properties of ethylic biodiesel

Despite the several advantages compared to conventional diesel fuel, the biodiesel has poor cold flow properties, limitng its use as a fuel in moderate and cold climates. Considering that the fatty esters profile and the alcohol used affect the biodiesel physico-chemical behavior, this work explored the crystallization/melting profiles of ethyl biodiesel from different oil sources as well as of binary blends among them to improve their cold flow properties. Therefore, model ethyl biodiesels from soybean oil, beef tallow, palm oil, their fractions, olein and stearin, palm kernel, macauba, and macauba kernel oils were formulated by pure ethyl esters, their melting/crystallization temperature, cloud point, pour point, cold filter plugging point and the fraction of crystallized esters analysed. For all cases, blends decreased the cold flow properties of the heavier biodiesel. Soybean oil and tallow biodiesels, economically relevant sources, presented a CFPP of −4.28 °C and 17.12 °C, respectively, whilst some alternative sources, such as macauba and palm kernels biodiesels, presented values lower than −15 °C, which is more advantageous in cold climates. Tallow biodiesel was the only not in accordance with Regulation Agencies considering cold climates. Macauba and palm kernel oils were especially interesting to decrease the melting/crystallization temperatures of heavier biodiesels, including those from tallow beef. The best blend was those formulated with soybean and macauba kernel oils with a CFPP lower than −20 °C. This work suggested that not only biodiesels mainly composed by unsaturated esters but also by short-saturated esters could significantly improve the cold flow properties of high saturated biodiesel, being a low-cost and feasible alterative.

Repetitive loading of unroasted bulk palm kernels using UCTM for analysing optimum percentage kernel oil recovery and energy demand

Repetitive loading test of bulk palm kernels (unroasted) was conducted to determine the percentage kernel oil yield and energy demand using the universal compression testing machine (UCTM) of the maximum load of 200 kN and speed of 5 mm min−1. Pressing vessels of varying diameters (60, 80 and 100 mm) with a plunger were used together with the UCTM. The bulk palm kernels initial height of 60 mm was repeatedly compressed until permanent deformation was reached. The total amounts of mass of kernel oil leakage, deformation, percentage kernel oil and energy were measured/calculated. The main part of the study will be done using the mechanical screw press Farmer 20 - duo (Farmer 20, Farmet a.s., Ceska Skalice, Czech Republic) to determine the optimum processing conditions for achieving maximum kernel yield and specific energy requirement.

Solid-state fermentation of palm kernels by Yarrowia lipolytica modulates the aroma of palm kernel oil

Solid-state fermentation with Yarrowia lipolytica was applied to palm kernels (PK) with the aim to modulate the aroma of palm kernel oil (PKO) obtained after kernel roasting. The results showed that, the metabolic activities of Y. lipolityca brought about significant changes to the volatile profile of obtained PKO either by providing thermal reaction reactants or by directly contributing aroma compounds. After fermentation, a decreased content in glucose (60%) while an elevated amount (7-fold) in free amino acids was found in PK, which further impacted the formation of volatile compounds by influencing the Maillard reaction and Strecker degradation during roasting. More Strecker aldehydes and N-heterocyclic compounds were formed in PKO derived from fermented PK especially after intensified roasting. In addition, the catabolism of Y. lipolytica imparted some distinct volatile compounds such as 2-phenylethanol to the obtained PKO. However, the lipase excreted by Y. lipolytica hydrolysed PK lipids and released 5-fold more free fatty acids in fermented PKO, relative to the blank and control PKO, which likely contributed to the off-flavor. On the basis of all volatile categories, principal component analysis (PCA) clearly separated the fermented PKO from the blank and control PKO, with light roasted, fermented PKO being correlated with acids, alcohols and aliphatic aldehydes; medium and dark roasted, fermented PKO tending to be dominated by pyrroles, pyrazines and furanones, which is in correspondence with sensory changes of PKO. This study demonstrated that combining fermentation with roasting could provide a novel way to modulate the volatile composition and aroma of PKO.

Evaluation of soil-water ratio effectiveness in soil-bath wet separation process for kernel recovery

An appraisal of the soil-water bath (wet separation) method showed that the method is based on the difference in density/specific gravity of the palm kernels and the shells. In this study, the separation of palm kernel-shell mixture using separating agent other than clay soil (kaolin) in wet separation have been considered. Measured masses of soil were added incrementally into 40 L of water and its density calculated and recorded. The separation efficiency of an alternative medium (laterite) was compared with that of clay soil (kaolin). Different mass quantities of kernel/shell mixture were poured into the red mud soil (laterite) slurry, and stirred. The part of Kernel/shell mixture that floated were scooped off and the Kernel selected and weighed. From observations made, the density/specific gravity increases with increase in mass of separating agent in water. The separating efficiency increased with increased soil input, till the 18kg mark of soil input for both separating agents, when the floated kernel weight begins to be constant and highest. The optimal separation efficiency was found at medium/ water ratio of 0.45:1. The effectiveness of the red mud (laterite) sample was found to be comparable to clay (kaolin) at a medium-to-water ratio of 0.45:1 giving 98.93% efficiency. Thus, it is recommended to be used as an alternative to clay for wet separation. Keywords: Oil Palm Kernel, Kernel Shell, Wet Separation, Clay Soil, Red mud

Pretreatment of palm kernels with proteases modified the volatile flavor compounds of palm kernel oil

Pretreatment of palm kernels with proteases modified the volatile flavor compounds of palm kernel oil

Compressive loading experiment of non-roasted bulk oil palm kernels at varying pressing factors

Abstract Compression testing of non-roasted bulk oil palm kernels at different processing factors was performed using a universal compression testing machine and a pressing vessel witha plunger. The purpose of the research was to describe regression models of deformation, deformation energy and percentage kernel oil depending on force, speed and vessel diameter. The tested compression forces were 100, 125, 150, 175 and 200 kN, while the speeds were 5, 10, 15, 20 and 25 mm min−1. Three pressing vessels of diameter 60, 80 and 100 mm were used. Samples were compressed at an initial height of 60 mm. For varying forces and vessel diameters at a constant speed of 5 mm min−1, the values of deformation, deformation energy and percentage kernel oil ranged from 28.47±0.89 to 37.45±0.11 mm, 796±0.82 to 1795±49.01 J and 7.33±0.26 to 25.67±0.39%. At a constant force of 200 kN for different speeds and vessel diameters; the aforementioned determined parameters also ranged from 31.91±1.61 to 37.63±1.21 mm, 1012±26.76 to 1795±49.01 J and 14.66±0.42 to 24.98±1.37%. The results were statistically significant (p<0.05) or (F-ratio>F-critical), with high coefficients of determination between 0.74 and 0.99. Thus, higher force at specific speed may be needed to maximally recover kernel oil.

Experimental characterization and modeling of microwave heating of oil palm kernels, mesocarps, and empty fruit bunches

ABSTRACTThe current work investigates the microwave heating and drying behavior of oil palm fresh fruits and bunches. Dielectric, thermal, and mechanical properties of oil palm kernels (OPKs), mesocarps, and empty fruit bunches (EFBs) were determined. New empirical models of the dielectric constant, loss factor, elastic modulus, and yield stress as functions of moisture content were obtained for OPKs, mesocarps, and EFBs. The thermal conductivity of the mesocarps and EFBs was 0.458 and 0.0285 W/(m K), respectively. Thermal analyses showed that decomposition of OPKs, mesocarps, and EFBs started when the temperature exceeded 100°C. Multiphysics models that consider electromagnetic waves, moisture, and heat conservation as well as material deformation were developed for OPKs, mesocarps, and EFBs. The simulation results show that an EFB sample with high moisture content generated a high moisture gradient during heating, causing high stress that exceeded its yield stress. However, this effect occurred only during the initial heating. Our results show that microwave heating can aid the detachment of oil palm fruit from bunches before EFBs harden because of moisture loss.

Viscozyme L pretreatment on palm kernels improved the aroma of palm kernel oil after kernel roasting

With an interest to enhance the aroma of palm kernel oil (PKO), Viscozyme L, an enzyme complex containing a wide range of carbohydrases, was applied to alter the carbohydrates in palm kernels (PK) to modulate the formation of volatiles upon kernel roasting. After Viscozyme treatment, the content of simple sugars and free amino acids in PK increased by 4.4-fold and 4.5-fold, respectively. After kernel roasting and oil extraction, significantly more 2,5-dimethylfuran, 2-[(methylthio)methyl]-furan, 1-(2-furanyl)-ethanone, 1-(2-furyl)-2-propanone, 5-methyl-2-furancarboxaldehyde and 2-acetyl-5-methylfuran but less 2-furanmethanol and 2-furanmethanol acetate were found in treated PKO; the correlation between their formation and simple sugar profile was estimated by using partial least square regression (PLS1). Obvious differences in pyrroles and Strecker aldehydes were also found between the control and treated PKOs. Principal component analysis (PCA) clearly discriminated the treated PKOs from that of control PKOs on the basis of all volatile compounds. Such changes in volatiles translated into distinct sensory attributes, whereby treated PKO was more caramelic and burnt after aqueous extraction and more nutty, roasty, caramelic and smoky after solvent extraction.

“Imbibing the Lesson of Defiance”: Oil Palms and Alcohol in Colonial Ghana, 1900–40

This article examines a controversy over oil palm landscapes in colonial West Africa. Oil palms provide two important food products, palm oil and palm kernels, but they are also tapped for palm wine, an alcoholic drink produced from the sap of the tree. In Ghana (the colonial Gold Coast), the preferred wine-tapping method destroyed the tree, leading to conflicts among Ghanaians and with the colonial state over the best uses of oil palm trees. Many Ghanaian elites agreed with colonial officials that felling palms for wine was wasteful, but others defended palm wine as a symbol of resistance to colonialism. Although colonial officials tried to suppress the production of palm wine and spirits distilled from it, their efforts were halfhearted, reflecting skepticism about the environmental and economic cases for protecting oil palms. Felling palms for wine did contribute to the systematic degradation of Ghana’s once dense “palmeries,” but this was a complex transformation rather than a case of reckless overconsumption.

Electrochemical Immunosensor for the Detection of Aflatoxin B₁ in Palm Kernel Cake and Feed Samples.

Palm kernel cake (PKC) is the solid residue following oil extraction of palm kernels and useful to fatten animals either as a single feed with only minerals and vitamins supplementation, or mixed with other feedstuffs such as corn kernels or soy beans. The occurrence of mycotoxins (aflatoxins, ochratoxins, zearalenone, and fumonisins) in feed samples affects the animal’s health and also serves as a secondary contamination to humans via consumption of eggs, milk and meats. Of these, aflatoxin B1 (AFB1) is the most toxically potent and a confirmed carcinogen to both humans and animals. Methods such as High Performance Liquid Chromatography (HPLC) and Liquid Chromatography–Mass Spectrometry (LC-MS/MS) are common in the determination of mycotoxins. However, these methods usually require sample pre-treatment, extensive cleanup and skilled operator. Therefore, in the present work, a rapid method of electrochemical immunosensor for the detection of AFB1 was developed based on an indirect competitive enzyme-linked immunosorbent assay (ELISA). Multi-walled carbon nanotubes (MWCNT) and chitosan (CS) were used as the electrode modifier for signal enhancement. N-ethyl-N′-(3-dimethylaminopropyl)-carbodiimide (EDC) and N-hydroxysuccinimide (NHS) activated the carboxyl groups at the surface of nanocomposite for the attachment of AFB1-BSA antigen by covalent bonding. An indirect competitive reaction occurred between AFB1-BSA and free AFB1 for the binding site of a fixed amount of anti-AFB1 antibody. A catalytic signal based on horseradish peroxidase (HRP) in the presence of hydrogen peroxide (H2O2) and 3,3′,5,5′-tetramethylbenzidine (TMB) mediator was observed as a result of attachment of the secondary antibody to the immunoassay system. As a result, the reduction peak of TMB(Ox) was measured by using differential pulse voltammetry (DPV) analysis. Based on the results, the electrochemical surface area was increased from 0.396 cm2 to 1.298 cm2 due to the electrode modification with MWCNT/CS. At the optimal conditions, the working range of the electrochemical immunosensor was from 0.0001 to 10 ng/mL with limit of detection of 0.1 pg/mL. Good recoveries were obtained for the detection of spiked feed samples (PKC, corn kernels, soy beans). The developed method could be used for the screening of AFB1 in real samples.

Pentopan mono BG pretreatment of palm kernels modified the aroma of palm kernel oil after kernel roasting

With an interest to enhance the aroma of palm kernel oil (PKO), Pentopan mono BG (xylanase) was applied to alter the carbohydrates in palm kernels (PK) so as to modulate the formation of volatiles during kernel roasting. The result showed that a 1.3-fold increment of total soluble sugars was found in PK after Pentopan treatment, which promoted the generation of O-heterocyclic volatile compounds during kernel roasting. Overall, an increment of 1.5-, 1.4- and 1.3-fold of O-heterocyclic compounds were found in PKO derived from treated PK after light, medium and dark roasting, of which the elevation in furfural and 2-furanmethanol contents was the most obvious. Principal component analysis (PCA) clearly discriminated treated PKO with various kernel roasting degrees from that of control PKO on the basis of all aroma-active compounds; the aroma in PKO from treated, roasted PK was highly correlated with 2-[(methyldithio)methyl]-furan, 5-methyl-2-furancarboxaldehyde, 2-furanmethanol, 2,5-dimethylpyrazine and ethyl pyrazine. Sensory evaluation showed that PKO derived from medium roasted PK imparted more caramelic, nutty and smoky odor notes relative to the untreated PKO. This study suggests Pentopan pretreatment of PK followed by roasting may be a novel way to modulate PKO aroma and potentially widen its application.

Growth kinetic study of ionic liquid mediated synthesis of gold nanoparticles using Elaeis guineensis (oil palm) kernels extract under microwave irradiation

Gold nanoparticles (AuNPs) are the most studied nanomaterials due to their promising applications. However, surface capping of AuNPs is essential to protect aggregation for enhanced colloidal stability. In this study, a single step method was established to synthesize stable AuNPs using oil palm kernel (OPK) extract prepared in IL[EMIM][OAc] (1-ethyl-3-methylimidazolium acetate). Ionic liquids were used for phytochemicals extraction along with capping and stabilizing of AuNPs after their synthesis. The OPK extract reduced the gold precursor, and UV–vis spectroscopy revealed a sharp surface plasmon (SPR) peaks in the region of 524–529nm, which confirmed the formation of AuNPs. UV–vis and TEM analysis indicated that microwave assisted synthesis was rapid to synthesize well dispersed and small sized AuNPs in comparison with conventional heating. FTIR analysis of kernels extract before and after its reaction with gold precursor identified the involvement of CH aromatic groups, polyphenolic OH groups, and carbonyl amide groups that are responsible for reduction of trivalent gold ions to AuNPs. EDAX and XPS analysis were performed to identify the elemental gold and its surface interaction with ILs and other organic moieties. Colloidal AuNPs kept at room temperature for periods of six months were remained stable. The change of pristine nanostructure arises due to involvement of different driving forces during growth of nanoparticles. Thermodynamically instability of nanomaterials may leads to Ostwald Repining (OR) or adopt complex pattern of growth and undergo coalesce and orientation attachment (OA). These models were fitted to compare the theoretically growth of particles along with actual increase of particles size. Experimental results suggested that OA growth was originated in early phase, however, it substituted and mainly controlled by OR growth pattern over time.

Oil point and mechanical behaviour of oil palm kernels in linear compression

AbstractThe study described the oil point and mechanical properties of roasted and unroasted bulk oil palm kernels under compression loading. The literature information available is very limited. A universal compression testing machine and vessel diameter of 60 mm with a plunger were used by applying maximum force of 100 kN and speed ranging from 5 to 25 mm min−1. The initial pressing height of the bulk kernels was measured at 40 mm. The oil point was determined by a litmus test for each deformation level of 5, 10, 15, 20, and 25 mm at a minimum speed of 5 mmmin−1. The measured parameters were the deformation, deformation energy, oil yield, oil point strain and oil point pressure. Clearly, the roasted bulk kernels required less deformation energy compared to the unroasted kernels for recovering the kernel oil. However, both kernels were not permanently deformed. The average oil point strain was determined at 0.57. The study is an essential contribution to pursuing innovative methods for processing palm kernel oil in rural areas of developing countries.

Comparative microstructure study of oil palm fruit bunch fibre, mesocarp and kernels after microwave pre-treatment

The implementation of microwave technology in palm oil processing offers numerous advantages; besides elimination of polluted palm oil mill effluent, it also reduces energy consumption, processing time and space. However, microwave exposure could damage a material’s microstructure which affected the quality of fruit that can be related to its physical structure including the texture and appearance. In this work, empty fruit bunches, mesocarp and kernel was microwave dried and their respective microstructures were examined. The microwave pretreatments were conducted at 100W and 200W and the microstructure investigation of both treated and untreated samples were evaluated using scanning electron microscope. The micrographs demonstrated that microwave does not significantly influence kernel and mesocarp but noticeable change was found on the empty fruit bunches where the sizes of the granular starch were reduced and a small portion of the silica bodies were disrupted. From the experimental data, the microwave irradiation was shown to be efficiently applied on empty fruit bunches followed by mesocarp and kernel as significant weight loss and size reduction was observed after the microwave treatments. The current work showed that microwave treatment did not change the physical surfaces of samples but sample shrinkage is observed.