Kernel Mass Research Articles

Analysis of Corn Drying Rack Position on Tray Type Dryer on Drying Rate

This research aims to determine the drying characteristics of corn kernels using a tray-type dryer, including the moisture content of the corn kernels over time, the mass of the tested corn kernels over time and the drying rate over time. This research uses the experimental method. The drying process uses an incoming drying hot air temperature of 65ºC with an incoming hot drying air speed of 2 m/s, repeated three times until a water content of 14 ± 0.5% is reached. The dryer in this study used four stacking shelves counting from the bottom, which were filled with 500 grams per shelf. This research shows that the further the shelf is positioned from the incoming hot drying air, the lower the drying rate. Vice versa, the closer the drying Shelf is to the incoming hot air, the greater the drying rate. The average decrease in corn kernel mass was 0.95% for shelf 1, 0.93% for shelf 2, 0.90% for shelf 3 and 0.88% for shelf 4 during a drying period of 3.5 hours. The average decrease in water content was 4.4% for shelf 1, 4.29% for shelf 2, 4.15% for shelf 3 and 4% for shelf 4 during a drying period of 3.5 hours. The further the position of the shelf from the hot air dryer, the less air content contained in the material on the shelf can be absorbed by the hot air dryer and vice versa. The average drying rate was 16.8% for shelf 1, 15% for shelf 2, 13.6% for shelf 3 and 12.8% for shelf 4 during a drying period of 3.5 hours at a drying hot air temperature of 65oC with a drying air speed of 2 m/s. The research data analysis results showed that the hot air dryer should not be passed from below but rather from the side. This affects the drying process in the dryer and makes it evener.

Systematization of sunflower genotypes based on seed phenotypic characteristics using neural networks

In recent years, various datasets related to the phenotyping of sunflower genotypes have become increasingly accessible. However, one of the key challenges remains the efficient and accurate prediction of phenotypes based on genotypes in the context of climate change. Analyzing phenotypes at different levels of organization and detecting connections between phenotypes and genotypes require the integration and processing of large, diverse, and often noisy datasets. Machine learning offers a broad arsenal of methods and approaches for identifying predictive patterns in such data. Therefore, the research aimed to develop a methodology for the systematization of sunflower genotypes based on seed phenotypic characteristics using the data vector quantization method and neural networks. The study revealed the phenotypic characteristics of sunflower seeds from various genotypes selected by the Institute of Oilseed Crops of NAAS, grown in the southern Steppe of Ukraine, including seed length, width, thickness, seed mass, kernel mass, and seed coat cracking force. For this purpose, appropriate laboratory equipment was developed, including two modules for determining the morphological and rheological properties of seeds. The developed methodology for the systematization of sunflower genotypes based on seed phenotypic characteristics includes the following steps: measuring the characteristics of sunflower seeds from various samples (parental components); studying the mutual correlation of characteristics; conducting hierarchical cluster analysis of the data using the Ward's method; determining the optimal number of groups; performing k-means clustering using the vector quantization method; determining the correspondence of ranges of characteristics to the group; training a neural network to group the data by samples and created groups; verifying the adequacy of the neural network on test data. The developed methodology was tested, and the MLP 30-15-3 neural network for grouping data by samples and created groups of sunflower seeds was developed in the Statistica software package. The network's training efficiency was 99.4%, and such of testing and validation was 95.6% and 96.7%, respectively.

Development of a true density-based automated quality grading device for unboiled arecanut kernels

The automated sorting of arecanut kernels is a significant challenge that has not been effectively addressed thus far. Scientific grading techniques are necessary given the paradigm change toward investigating alternative uses for arecanuts in industry and the medical field. This research work emphasizes the relatively unexplored aspect of the post-harvest process; quality grading of kernels based on physical properties. It aimed to develop a novel approach for classifying unboiled (Chali) arecanut kernels cultivated in Goa, India based on their true density, using a combination of mechanical and visual techniques. The study explored the potential of true density as a quality indicator for real-time grading of the kernels. To achieve this, automated grading equipment was devised, utilizing a load cell to measure the kernel's mass and the ellipsoid approximation method to estimate its volume. A machine vision system captured the top and side images of the kernels to measure their volume. Python programs were created to enable image acquisition, processing, object detection, measurement and kernel segregation. Real-time kernel classification was accomplished by establishing serial data communication between the Python code and the Arduino board. The kernel segregation process was facilitated by servomechanism and a stepper motor. The kernels were classified into acceptable and non-acceptable categories based on a threshold value of true density. The research successfully established a method that utilizes the physical attributes of arecanut kernels as parameters for quality grading. However, the study encountered challenges with the density measurements, as the paired t-test results revealed significant differences between the kernel true density measured by the device and the true density estimated using the weighing scale-water displacement method, indicating a percentage error of 13.2%. Addressing these challenges would lead to more accurate density calculations, thereby enhancing the overall effectiveness of the kernel classification process. Furthermore, the technique allowed for the offline estimation of the kernels' porosity, which was found to be 45.3%. In future research, the integration of density and porosity measurement systems could be explored for real-time quality evaluation based on porosity, offering potential opportunities for further enhancement and optimization of the grading process. The technology could be further applied to other types of nuts and agricultural products, thereby overcoming the limitations of color-based sorting using image processing. Key words: Quality grading, True density, Machine vision, Arecanut kernel, Python

High Outcrossing Levels among Global Macadamia Cultivars: Implications for Nut Quality, Orchard Designs and Pollinator Management

Global fruit and nut yields are affected by shortfalls in pollinator populations, and pollen limitation is most prevalent among tropical, bee-pollinated and self-incompatible plants. Macadamia is a subtropical, bee-pollinated crop in which some cultivars have been found to be highly outcrossing. We aimed to determine the extent of outcrossing and its effects on nut quality across a wide range of international macadamia cultivars in three countries. We sampled fruit from 19 macadamia cultivars across 23 sites in Australia, Brazil and South Africa. We used genotype-by-sequencing and MassARRAY methods to assign paternity to individual fruit and we assessed pollen-parent effects on nut quality. Macadamia was highly outcrossing, producing 80–100% of fruit by cross-pollination, at 17 of the 23 sites. Mixed mating (41–72% outcrossing) was identified at five sites, and low outcrossing (10%) was identified in one cultivar at one site where it was isolated from other flowering macadamia trees. Outcrossed fruit often had significantly better quality than selfed fruit, with 1.61–3.39 g higher nut-in-shell mass, 0.53–1.55 g higher kernel mass, 3.3–6.4% higher kernel recovery, and 3.0–3.5% higher oil concentration. The differences in kernel recovery equated to differences in value of USD 433–841 per ton of nut-in-shell at prices of USD 3000 per ton. In summary, macadamia cultivars were mostly highly outcrossing, and outcrossed nuts often had higher quality than selfed nuts. Growers should consider interplanting different cultivars more closely and distributing bee hives more widely to maximise cross-pollination, produce high yields, and optimise nut quality.

A Study of the Distribution of the Threshed Mixture by a Double Longitudinal Axial Flow Corn Threshing Device

In order to determine the distribution pattern of the threshed mixture in the double longitudinal axial flow threshing device, single-factor experiments were conducted on the self-developed experimental platform for the double longitudinal axis threshing device. The experimental factors included drum speed, threshing clearance, and feed rate. The variations in the distribution of the threshed material along the axial and radial directions were examined. The results indicate that the mixed material after threshing exhibits uneven distribution both axially and radially. Along the axial direction, the mass of corn kernels initially increases and then decreases and is predominantly distributed in the front one-third section of the drum. Meanwhile, the mass of corn cobs continuously increases. In the radial direction, the mass of corn kernels and cobs is higher in the middle and on both sides, with the corn kernels being most concentrated in the middle and the corn cobs mostly on the sides. Combining the corn kernel breakage rate and the unthreshed rate, the optimal operating conditions were determined as follows: a drum speed of 400 r/min, a concave clearance of 50 mm, and a feed rate of 16 kg/s.

Procena nekih fizičko-mehaničkih karakteristika pšeničnog zrna kod određenog sadržaja vlage

Physical properties and mechanical properties of grains have importance in design of farm machinery, processing equipment's, handling equipment's, and processing of food and agricultural products. The physical properties must be known to an engineer to design a machine for handling, cleaning, conveying, storing and milling. There are some of important physical properties such as shape, size, volume, density and mechanical properties like angle of repose, static friction coefficient of different grains is necessary for the design of seed drill cum fertilizer, harvester, thresher etc. and food processing units such as separating, handling, storing, drying systems etc. Physical and mechanical properties of grain were estimated at Food Research Lab, Food and Processing Engineering, Vaugh Institute of Agricultural Engineering and Technology, Sam Higginbottom University of Agriculture, Technology and Sciences, Prayagraj, (Uttar Pradesh). Therefore, The objective of present study was to determine some physical and mechanical properties of wheat grain at 9.2 % moisture content such as dimensions (length, width and thickness); equivalent, geometric and arithmetic mean diameter; sphericity; surface area; area of flat and transverse surface; volume; mass of one grain; and then other properties under effect of moisture content variation such as density, thousand kernel mass, coefficient of friction against deferent materials and angle of repose. The average length, width and thickness of wheat seed were measured 6.25, 4.48 and 3.73 mm at a moisture content of 9.7 % (wet basis) respectively. Equivalent diameter and sphericity were calculated at moisture content of 9.7 % were 4.63 mm and 74 %. The bulk density and particle density was estimated 623 and 1215 kg/m3 at same moisture content while mechanical properties such as angle of repose and static friction were determined 24.60 and 0.352 respectively at same moisture level. Therefore, these estimated physical and mechanical properties can be used to design and development of combine tillage and sowing assembly.

O desbaste de plantas afeta as características físico-químicas e compostos bioativos das cultivares de noz-pecã ‘Barton’ e ‘Melhorada’

ABSTRACT The production and consumption of pecan nuts have been on the rise in recent times, which renders it necessary to study the best production practices to increase the yield, enhance the flavor, and maintain the bioactive components in the final product. The present study, therefore, aimed to verify the effects of tree thinning on the physicochemical characteristics and bioactive components in pecan under the cultivation conditions of Santa Rosa, Rio Grande do Sul. The pecan plants were submitted to two types of management - with thinning and without thinning, following which the fruits were evaluated for physical (size, weight, and color) and chemical (physicochemical composition, oxidative stability, fatty acid profile, and tocopherols) attributes. The results revealed that the thinning of plants increased the size and mass of both nuts and kernels while reducing the acid content and peroxides in the kernels and increasing the γ-tocopherol levels. The other quality evaluations did not reveal any significant alterations after plant thinning.

A phenomenological model for predicting the early development of the flame kernel in spark-ignition engines

This work presents a simple and effective phenomenological model for the prediction of the early growth of the flame kernel in SI engines, including its initiation as a result of the electrical breakdown of the fuel/air mixture between the spark plug electrodes. The present model aims to provide an improved description of the ignition-affected early phases of flame kernel development compared to the majority of models currently available in literature. In particular, these models focus on electrical energy supply and turbulence, whereas the stretch-induced kernel growth slowdown is quantified with linear models that are inconsistent with the small kernel radius. For the flame kernel initiation, this model replaces the current methods that rely on 1D heat diffusion within a plasma column with a more consistent analysis of post-breakdown conditions. Concerning the kernel growth, the present model couples the mass and energy conservation equations of a spherical kernel with the species and temperature profiles outside of it. This combination leads to a non-linear description of the flame stretch, according to which the kernel development is controlled by the Lewis-number-dependent balance between the heat gained via combustion and the heat lost via thermal diffusion. As a result, the kernel temperature differs from the adiabatic flame temperature, causing the laminar flame speed to change from its adiabatic value and ultimately affecting the overall kernel development. Kernel growth predictions are conducted for laminar flames and compared to literature data, showing a satisfactory agreement and highlighting the ability to describe the stretch-induced kernel slowdown, up to its possible extinction. A good agreement with literature data is also obtained for kernel expansions under moderately turbulent conditions, typical of internal combustion engines. The simple formulation of the present model enables swift integration into phenomenological combustion models for sparkignition engines, while simultaneously offering useful insight into the early kernel development even for CFD-based approaches.

Characterization of Cashew Nut (Anacardium occidentale L.) Germplasm for Kernel Quality Attributes

Ensuring the quality attributes of cashew kernels is essential for selecting superior genotypes with agro-industrial potential. Therefore, this study characterized cashew nut accessions from the Cashew Germplasm Bank regarding kernel quality standards and identified genotypes with optimal characteristics for the industry. The characterization included key industrial indicators such as peeling efficiency, average kernel mass, class, type, and industrial yield, evaluated in 47 different accessions. Through multivariate cluster analysis and principal component analysis, the accessions revealed four distinct groups, exposing correlations among various industrial indicators. The analysis revealed a diverse genetic profile within the Cashew Germplasm Bank. A notable finding is that 80.85% of the accessions group together, displaying predominant features—easy peeling, an average mass exceeding 2.5 g, categorized as super large (SLW) and large (LW), and uniformly white-colored kernels. Correlations found include a negative relationship between kernel mass and class and positive associations between class and industrial yield, as well as between industrial yield and peeling efficiency. The study reveals substantial variability in cashew nut germplasm with respect to quality traits, highlighting its invaluable potential for identifying and selecting superior genotypes adapted for agro-industrial purposes. Particularly promising are Group 4 accessions, such as BGC632, BGC589 and BGC127, presenting attributes indicative of high-quality kernels.

Geographical variation in Canarium indicum (Burseraceae) nut characteristics across Vanuatu

AbstractTropical forests in the Pacific region contain many tree species that bear edible nuts (kernels). Canarium indicum (canarium) is an overstorey tree indigenous to Melanesia that produces commercially valuable kernels due to their pleasant taste and high oil content. This study characterises natural variation in fruit, nut-in-shell (NIS) and kernels of C. indicum across eight islands in Vanuatu. Significant tree-to-tree variation in fruit, NIS and kernel characteristics as well as kernel recovery (kernel:NIS) was found. This variation was largely due to tree-to-tree differences and little of this variation could be attributed to location. There were significant linear correlations among fruit, NIS and kernel traits, including kernel mass with fruit mass (R2 0.57) and kernel mass with NIS mass (R2 0.56). Therefore, trees suitable for cultivation may be screened based on fruit and nut characters before making final selections based on kernel mass. Trees sampled over two fruiting seasons showed that kernel mass and kernel number varied significantly between years for 63.6% and 25.9% of the trees respectively. However, by rank order, those trees that produced larger kernels in the first year of sampling, tended to also produce relatively larger kernels in the subsequent year. The implications of these results for the further domestication of the species for planting in commercial agroforestry systems is explored.

Soybean yield response to different mechanical weed control methods in organic agriculture in Luxembourg

Soybean (Glycine max (L.) Merr.) is very sensitive to interferences with weeds during vegetative growth. Weed control is a key factor for the successful production of soybean in organic agriculture. In Luxemburg, where soybean is not yet an established crop, cultivation trials were implemented to test and evaluate different methods of mechanical weed control in soybean cultivation. Trials were conducted in 2018 and 2019 at three locations in Luxembourg. A flex-tine harrow that can harrow the whole ground surface and a hoe used as inter-row cultivator were the basis of the mechanical treatments. Complementary technologies for the hoe such as the finger weeder, and an alternative method involving intercropping of soybean with camelina were also integrated in the trials. The main objective of the study was to evaluate the efficiency of the tested methods regarding weed regulation and their effects on soybean growth and development and grain yield. In comparison to the weed-free control, both hoeing and harrowing led to yields losses; these losses were lower with hoeing (- 2 %) than with harrowing (- 34 %). Yields were similar between hoeing and hand weeding and were also similar between harrowing and the weed-free control. The weed control index based on the difference in weed cover compared with the non-weeded treatment was above 0.6 for hoeing, about 0.2 for harrowing and lower than 0.01 for intercropping. Intercropping with camelina was not suitable for Luxembourg, especially during the dry study years of 2018 and 2019 due too poor establishment. Intra-row weeding with finger weeder in addition to inter-row hoeing did not significantly enhance the single use of the hoe in the inter-row. The non-selectivity of harrowing generated more soybean plant losses (- 28 %) and lower plant height (- 8 %) than hoeing (- 11 % and + 5 %, respectively) when compared with the weed-free control. Other yield components such as the number of pods per plant, number of beans per pod, thousand kernel mass, and the first pod height were not significantly affected by the weeding method. The efficiency of any treatment was low when weed infestation was already high after soybean emergence, although where weed infestation was low, any of the treatments were applicable. Encouraging rigorous weed management throughout the crop rotation is a key factor to maximize soybean yield.

Effect of moisture content on engineering characteristics of apricot (Prunus armeniacaL.) kernel

AbstractApricot (Prunus armeniaca L.) kernels, the innermost part of the economical stone fruit, are utilized for edible purposes, extraction of oil, and many pharmaceutical products. Biological materials are complex in structure and get affected by their moisture content. This study investigates the effect of different moisture content from 5.66% to 26.47% wet basis apricot kernels on its various engineering characteristics and develops their correlations. The engineering characteristics such as linear dimension length (13.26–14.47 mm), breadth (8.69–9.97 mm), thickness (5.36–6.50 mm), arithmetic mean diameter (9.11–10.32 mm), geometric mean diameter (8.48–9.77 mm), surface area (227.91–302.68 mm2), projected area (91.99–114.95 mm2), 1000 kernel mass (0.317–0.403 kg), true density (881.23–973.55 kg m−3), and porosity (33.74%–43.68%) increased linearly with moisture content. On the other hand, bulk density (548.23–583.89 kg m−3) and elongation ratio (2.25–2.51) showed a decreasing trend with an increase in moisture content. The frictional properties such as angle of repose (22.81–28.92°) and coefficient of static friction value for glass, stainless steel, galvanized iron, and wood were found to increase with increased moisture content and ranged from 0.179–0.283, 0.272–0.347, 0.416–0.512, and 0.488–0.595, respectively. The highest static coefficient of friction was observed for wood surfaces. A significant difference in color values L*, a*, b*, hue angle (H), chroma (C), and ∆E values were observed at different moisture content. Terminal velocities and hardness of AK increased linearly with moisture content and the values were found between 4.26 and 5.91 m s−1 and 21.59 to 35.25 N mm−1, respectively.Practical applicationsApricot kernels have nutritional and pharmaceutical value due to the abundance of bioactive components in them but are still underutilized due to a lack of handling knowledge and processing mechanization. Apricot kernels are delicate and sensitive for mechanical damage during every stage of their processing. This study investigates engineering characteristics in view to understand their relationship with moisture content, as many instruments and equipment are yet to be designed. Knowledge of its engineering characteristics at different moisture content would help handlers for quality evaluation, and manufacturers in optimally designing processing machinery and quality analytical instruments.

Changes in the Properties of Hazelnut Shells Due to Conduction Drying

In this study, the physical properties of two hazelnut species were investigated before and after drying at different temperatures and durations. The results showed that the physical properties of the hazelnut samples, including size, volume, density, weight, kernel mass, and shell mass, were significantly affected by temperature, duration, and their interactions. In addition, the moisture content of the samples decreased with increasing temperature and drying duration. The lowest value for the Istarski duguljasti variety was 5.36% (160 °C and 45 min), while the lowest value for Rimski okrugli was measured at 160 °C and 60 min (5.02%). Ash content was affected by both temperature and time, with the Istarski duguljasti variety having a minimum value of 0.84% at 120 °C and 60 min and Rimski okrugli a maximum value of 1.24% at 100 °C and 30 min. The variables of the ultimate analysis, such as nitrogen, carbon, sulfur, and hydrogen, increased with increasing temperature and time. The oxygen content and the higher heating value decreased with increasing temperature. Energy optimization in the drying process is crucial to reduce costs and save time. Effective energy optimization measures can lead to significant cost savings and improved operational efficiency in the drying process.

An analysis of the correlations between the hardness index and selected physicochemical properties of wheat grain

The processes of grain grinding and milling are affected by the physical properties of kernels, whereas energy consumption during these processes is influenced mainly by their mechanical properties. Therefore, the main aim of this study was to determine the relationships between selected physicochemical properties of wheat grain classified into different hardness groups. Technological (processing), mechanical and geometric properties of grain were evaluated in 12 wheat cultivars produced in Poland. The cultivars were divided into four grain hardness groups. The results were analyzed using the following statistical modules: descriptive statistics, one-way analysis of variance (ANOVA), correlation analysis, and regression analysis. Kernels of various hardness were found in each of the evaluated wheat cultivars, in particular those classified as medium soft and medium hard. The type and strength of correlations between the analyzed properties of grain were considerably affected by kernel hardness. The greatest differences were observed in comparisons of the following pairs of kernel parameters: length and width, length and relative strain, length and rupture force, and rupture force and relative strain. On average, the strongest correlations were noted between rupture force and rupture energy, and between kernel thickness and mass, whereas the weakest correlation was found between kernel mass and relative strain. The study demonstrated that the mechanical properties of wheat grain were not affected by crude protein content or total ash content. Grain hardness was correlated with kernel length, vitreousness, rupture force, and rupture energy. The hardness index (HI) increased by 110% within the range of average kernel length values (from approx. 5.4 mm to approx. 8.0 mm). The increase in HI values was accompanied by an increase in rupture force (by approx. 90%) and rupture energy (by approx.115%).

Energy Performance Improvement of a Solar Still System Using Date and Olive Kernels: Experimental Study

AbstractCurrently, solar distillation systems are used to contribute to solving the fresh water supply deficiency problem in some desert and rural areas. The present outdoor experimental work aims to improve the energy performance of a solar still installed in a semi‐arid region. Experiments are performed using three solar distillers (a reference system, a distiller with date kernels, and one with olive kernels). The integration effect of two kernel types date and olive with different concentrations in the range of 300–600 g kernels per 5 L on the hourly and cumulus water production, and thermal and exergy efficiencies are analyzed. The results show that, for the same kernel mass concentration, the system with olive kernel is more effective than that with date kernels; moreover, compared to the reference system, cumulus water production of these systems at a mass concentration of 500 g kernels per 5 L is higher by ≈226% and 176%, respectively. At a concentration of 500 g kernels per 5 L, the average daily thermal efficiency of the solar still with olive kernels and that with date kernels is 38.01% and 30.7%, respectively, and their daily average exergy efficiency is 8.4% and 3.1%, respectively.

Study on morphological parameters of the sweet almond nut (Amygdalus communis l.)

This article delves into the morphological features of various sweet almond (Amygdalus communis L.) varieties and forms, with the aim of analyzing their characteristics and applying the findings to obtain new types of almonds. Thirteen different sweet almond varieties were studied, including their total weight, kernel mass, number of seeds, and seed ratio. The results showed that one genotype (Qamashi-3) had medium to large nuts, while the other twelve genotypes had small nuts. All genotypes had easily peeled shells. Of the selected varieties, 15.38% were very large, 46.15% were medium to large, and 38.46% were small-fruited. The length, width, and thickness of the nut varied from 22.0 mm to 39.2 mm, 14.0 mm to 23.0 mm, and 11.0 mm to 16.5 mm, respectively. The thickness of the seed coat ranged from 1.5 mm to 3.1 mm. The number of nuts per 1 kg differed across varieties, ranging from 139 to 1076 pieces. Two genotypes had very hard shells (Tosh almond, Qamashi-3), four had hard shells, three had medium-hard shells, and six had soft shells. Most of the genotypes had sweet grains (12 genotypes), while one had a bittersweet taste. Overall, the studied sweet almond genotypes are important for expanding the genetic base in Uzbekistan through hybridization with each other or with standard varieties.

Influence of geographic provenance on phenotypic variation in seed and kernel traits of the African oil tree from southern Benin and implications for species breeding

Knowledge of oilseeds plants’ traits and features is fundamental to understanding the natural selection process and improving conservation programs through species selection. As a forest oilseed, Ricinodendron heudelotii is the object of growing interest among value chain actors, who are increasingly interested in its intrinsic characteristics. To date, there is a lack of information on plant morphological traits for the selection of the best genotype, especially as far as seed and kernel traits are concerned. The aim of this study was to make a typology and establish the relationship between seed and kernel traits of Ricinodendron heudelotii, depending on provenances represented by wild populations of trees in southern Benin. We sampled the provenances constituted equally and per tree, ten random samples each of fruits, seeds, kernels, and shells were collected for measurement. Hierarchical classification, common component analysis, Pearson’s, and Chi-square association tests were performed for statistical analysis. Substantial variation between seed and kernel traits was observed between and within provenances. High coefficients of variation for the quantitative descriptors (length, width, and mass) of seeds and kernels appear to be the essential traits that discriminate the plant into two morphotypes. Furthermore, seed and kernel characteristics show a significant positive correlation with these discrimination criteria. The upper morphotype contains accessions from three provenances with huge seeds and kernels but few seeds per fruit, while the lower morphotype includes the other provenances with tiny seeds and kernels. The results of the study provided essential information that could be an avenue for improvement with further biochemical and molecular characterization studies.

Physicochemical characterization of microwave-stabilized rice bran oil from Ethiopian small-scale rice-processing plants

Rice bran is one of the main byproducts of rice-processing industries, making approximately 10% of the total mass of rice kernels. It is rich in bioactive phytochemicals, which have several health benefits. Among others, rice bran contains 10%–23% oil, constituting the major bioactive elements of the bran. The aim of this work is therefore to evaluate rice bran oil obtained from Ethiopian small-scale rice-milling plants for suitability of human consumption. The rice bran was stabilized using microwave heating to inactivate endogenous lipase enzymes that would otherwise cause rancidity of the oil and render it inedible. The oil was then extracted and evaluated for its physicochemical properties, fatty acid composition, and antioxidant activity using standard methods. The result of the work confirmed that the rice bran oil from Ethiopian rice-milling plants has physicochemical characteristics that satisfy the acceptable threshold values set by various organizations. Interestingly, the oil contained a substantial fatty acid profile (high amount of unsaturated fatty acids) and a high content of unsaponifiable matter which contributes to the claimed health benefits of the oil. In addition, it exhibited a strong antioxidant activity (95.319%) at a concentration of 18 mg/ml, which also essentially contributes to its health benefits. Proper integration of rice milling with byproduct utilization such as rice bran oil production will contribute to the efforts to alleviate the oil scarcity in the country.

Determination of Content and Oil Losses in Meal through Palm Kernel Pressing Process at PT XYZ Belawan

<p class="E-JOURNALAbstractBodyEnglish">PT XYZ Belawan has a kernel crushing plant unit that produces Crude Palm Kernel Oil (CPKO) with 700 tons/day capacity. Palm kernel processing is carried out in two pressing stages. The first stage or first press produces oil and cake, while the second stage or second press produces oil and meal. The meal still contains 7-8% of the oil content. This study is aimed to determine the amount of CPKO yield, oil content, and oil losses in a meal during the pressing palm kernel process. The method used was the calculation of the mass balance in each process flow. The mass balance calculation is carried out after collecting the secondary data from the factory, including the analysis of water content, solids, FFA, and oil content. Based on the calculation results, CPKO yield was 48.10% of the average kernel mass rate of 714.7155 tons and met the plant standard of at least 44%. Furthermore, the average yield of oil content from the meal was 7.45% and oil losses were 3.86%.</p>

English

Two traditional treatments for shea (Vitellaria paradoxa) butter processing namely storage of fresh nuts and duration of subsequent boiling were studied by using the response surface methodology (RSM) to determine best treatment. Experimental treatments influenced several kernel parameters, such as fat content (38-52% dw), redness (a* values between 6.3 and 11.7), and butter parameters, viz. yield (24 to 36% wet weight of kernel mass), brightness (L* values between 70-80), yellowness (b* values between 16-23), and free fatty acid (FFA) percentage (0.5-2%). On the other hand, the moisture content (6-8%) of the kernels and the peroxide values (2.3 - 3.8 meq O2/kg) of the butter were not affected. Storage for 3 days and boiling for 28 ± 3 min gave the best results,  that is, kernels with a moisture content of 7% and a fat content of 50% dw. Butter extracted by traditional technique from these kernels yielded 32% on wet weight of kernel mass with 0.8% of FFA, and 2.5 meq O2/kg of peroxide. This butter can be used for food and cosmetic purposes without refining. Furthermore, the microstructure of fresh shea nuts, studied with Laser Scanning Confocal Microscopy, showed large and small fat globules with some free spaces inside.   Key words: Vitellaria paradoxa, kernels, storage, boiling, physico-chemical characteristics, shea butter.