Average Pulp Research Articles

Analysis of Physiological and Biochemical Parameters in the Radish (Raphanus sativus L.) Obtained in Different Cultivation Systems

This paper presents the results obtained from the analysis of physiological and biochemical parameters in the radish, species Raphanus sativus L., variety Rond Ecarlate, which was grown in three different systems (in the field, in the solarium and in the climate chamber). Several parameters necessary for the evaluation of biomass, physiological processes and nutritional values were determined. Regarding the biometric parameters, it was noticed that in the field cultivation the plants formed 11-12 leaves, in the solarium average 12-13 leaves, and in the climatic chamber the analyzed plants formed 7-9 leaves, on an average. The total biomass of the plant was recorded with the following average values: in the field 70.05 grams, in the solarium 92.3 grams and in the climate chamber 32.9 grams. Regarding the circumference of the tuberous hypocotyl axis, the values are higher in plants grown in solarium (16.9 cm), with the smallest dimensions being recorded in plants grown in the climate chamber (7.2 cm). The highest average pulp firmness value was observed in plants grown in the solarium (0.27 kg force), and the lowest values were seen in plants grown in the climate chamber (0.14 kg force). Regarding the amount of water lost through perspiration by the leaves of radish plants, the highest average values were recorded at plants grown in the solarium, and the lowest at plants grown in the climatic chamber. The average soluble dry matter content was higher (over 4%) in plants grown in the climate chamber compared to other harvesting systems. The analysis of the average carbohydrate content shows that the total soluble carbohydrates were present only in the hypocotyl axis and glucose was found both in the hypocotyl axis of the studied plants and in the leaves. Vitamin C was present in variable amounts, both in the hypocotyl axis and in the leaves. The average amino acid content (expressed in amino nitrogen) was between 0.003% and 0.006%. The anthocyanin was present with highest values (54.5 mg) in field-grown plants, and catalase activity was present both in the hypocotyl axis and in the leaves and roots. Air humidity and temperature had a high influence on the development of plant biomass, on the content of dry matter and on the loss of water through transpiration. The biometric, physiological and biochemical parameters varied depending on the cultivation system.

Preparation of fiber raw materials by cooking golden bamboo grass (Arundo donax) with calcified regenerated alkali solution

The increasing consumption of paper products has led to a shortage of paper fiber raw materials. It is necessary to develop new plant materials to alleviate the shortage of fiber suitable for papermaking. In this study, the fast-growing plant golden bamboo grass (Arundo donax), which is cultivated and planted in Guangxi province of China, was used as a new material for pulping. The average pulp yield by cyclic-cooking method averaged 48.6%, being 4.1% greater than the pulp yield by the ordinary caustic soda method. Much of the increased yield was attributable to the reprecipitation of lignin onto the fibers. The paper properties of the pulp prepared by cycle-cooked method did not decrease significantly, compared with the pulp prepared by the usual single-cooked method. Therefore, the pulp met the requirements of national standards of many kinds of papers. However, the pulp was not suitable for bleaching, due to its high consumption of oxidizing agents to reach the required brightness. Therefore, this research demonstrates that the fast-growing plant, Arundo donax is a good raw material for pulp, and the innovative method of cycle-cooking method can significantly improve the pulp yield.

THE BEHAVIOR OF SOME MELON CULTIVARS (CUCUMIS MELON) ON THE SANDY SOILS FROM SCDCPN DĂBULENI

The study was carried out in an experimental plot in 2023 on the sandy soils of SCDCPN Dăbuleni, characterized by low natural fertility, having in the 0-20 cm soil layer an organic carbon content of 0.56% and a humus content of 0.96 %. Seven melon cultivars were studied in the experimental field, observing a great diversity of their morphological and biochemical characteristics. Morphological characteristics such as fruit weight, fruit length and diameter, diameter of the seminal cavity, pulp thickness, and sugar content were determined for the analyzed fruits. Among the analyzed cultivars, stood out the AS 086 cultivar with an average fruit weight of 2.08 kg and the Traian cultivar with an average pulp thickness of 3.94 cm. Regarding the sugar content, the highest value was recorded for the cultivar AS 084, respectively 11.40%. From the point of view of the realized productions, the AS 038 cultivar stood out with a production of 29.07 t/ha, the lowest production being recorded for the AS 088 cultivar, respectively 22.33 t/ha.

Nutritional characterization, antioxidant activity and bergenin content of the pulp of Endopleura uchi

ABSTRACT The yellow uxi (Endopleura uchi) is a tree native to the Amazon and its fruits are appreciated in the region. It is rich in total phenols and its bark is known to have high bergenin content, an isocoumarin derivative that presents several pharmacological activities. Yet the nutritional and functional properties of the fruit are still little known. We analyzed the nutritional, centesimal, and mineral properties, and the antioxidant activity and total phenol content of the alcoholic extract of yellow uxi fruit pulp from different locations in the Amazon. The bergenin content was also quantified. Average pulp yield was 45.66 ± 4.44% (w/w), with 60.1 - 89.2 g 100 g-1 of moisture and 1.28 - 1.32 g 100 g-1 of ash (dry basis). Calcium (78.2 - 87.1 mg 100 g-1) and potassium (260.2 - 395 mg 100 g-1) were the most abundant minerals in the pulp. Aluminum concentration was high compared to other Amazonian fruits (23.7 - 28.7 mg 100 g-1). The high caloric value of the pulp (325.3 ± 20.9 Kcal 100 g-1) is attributed to its lipid (32 - 44.9%) and carbohydrate (48.2 - 64.1%) content. The scavenging activity of DPPH was 1.95 - 20.68%, which was highly associated with the total phenolic content (16.91 - 30.07 µg GAE mg-1). Bergenin content was 180.8 ± 55.3 mg 100 g-1. We conclude that E. uchi pulp has high caloric and mineral content, and it is also a source of bergenin, thus this fruit has a potential nutritional and functional value.

Yield and physical characterization of Passiflora cincinnata in the Brazilian Savanna

ABSTRACT For the Caatinga passion fruit (Passiflora cincinnata Mast.), there are no indications of varieties specific for the Brazilian Savanna conditions, as well as conduction techniques that make it possible to express a greater yield potential. This study aimed to evaluate the yield and quality of CPEF2220 and CBAF2334 populations in espalier and trellis conduction systems. A completely randomized design was used, in a 2 x 2 factorial arrangement, with three replications of four plants per plot. The fruit yield and physical characteristics were evaluated throughout the production cycle. The average yield was 8.0 kg plant-1 (3.5-14.9 kg plant-1) and the average number of fruits per plant was 139.1 (55.8-283.5), with average pulp yield of 29 %. There was a tendency to increase the number and yield of fruits for the CPEF2220 population conducted in the espalier system. The plant survival rate was 41 % (CPEF2220) and 87.5 % (CBAF2334), with a higher adaptation to the Brazilian Savanna conditions, while the CPEF2220 population presented a higher yield potential. Reductions in mass, longitudinal and equatorial diameter and fruit shape were observed throughout the harvest, with some exceptions for the espalier system, which showed more elongated fruits. The trellis system showed a greater yield potential for the parent populations of the passion fruit BRS Sertão Forte, for the study conditions.

Morfometría de frutos y semillas del “ají mochero” Capsicum chinense Jacq.

Capsicum chinense Jacq. “ají mochero” es catalogado como patrimonio gastronómico de Perú por su agradable grado de picor, que condimenta numerosos platos reconocidos internacionalmente. El boom gastronómico en Perú ha conllevado a la exportación de diferentes insumos nacionales, incluyendo el ají mochero, por lo que se requieren estudios agronómicos que brinden información sobre el estado productivo de los frutos y las semillas de este cultivo. El estudio buscó determinar la morfometría de los frutos y las semillas de C. chinense “ají mochero”. Para ello, se recolectaron frutos procedentes del distrito de Moche (provincia de Trujillo, departamento de La Libertad) y en el laboratorio se evaluó el peso del fruto y de la pulpa, así como las dimensiones y el número de semillas. Se realizó un análisis estadístico descriptivo con 50 repeticiones por cada componente evaluado. El peso promedio del fruto fue de 2,4 g y el peso promedio de la pulpa, de 2,1 g. La semilla registró una longitud promedio de 4,3 mm y un ancho promedio de 1,4 mm, y se reportaron 16,4 semillas por fruto. Se identificó un alto coeficiente de variación y una alta correlación (p < 0,01) entre los parámetros evaluados. Se concluyó que la morfometría de los frutos y las semillas de C. chinense “ají mochero” permite diferenciar esta de otras especies y variedades como C. annuum, C. baccatum, C. frutescens y C. pubescens. Esta información es primordial para promover su industrialización y fundamentar su denominación de origen.

Descrição biométrica de plantas e dos atributos quanti-qualitativos de frutos de icozeiro (Capparis yco) procedentes de áreas espontâneas no semiárido paraibano

The icozeiro (Capparis yco) is an endemic plant in the northeastern Brazil, with spontaneous access occurring in micro regions of the semi-arid region of Paraíba. However, there is practically no information about the plant or the characterization of its fruits from Curimataú in Paraíba. Based on that, this research aimed to describe the biometric characteristics of plants and the physical and chemical attributes of icozeiro fruits coming from spontaneous accesses. In plants, the variables evaluated were the following: height, stem diameter, crown diameter, leaf length and width, length of floral rachis, number of flowers per panicle and number of fruits. In the fruits, the physical characters were analyzed (equatorial diameter and length, total fresh mass, peel mass, seed mass, pulp mass, number of seeds, percentage of peel, percentage of peel, peel thickness and pulp yield), and chemical attributes (contents of soluble solids and pH). The plants presented average heights of 2.7 ± 0.8 m. Average canopy diameter was 2.4 ± 1.0 m, and average floral rachis length was 10.8 ± 4.9 cm and between 3.0 and 58.0 flowers per panicle. Analysis of fruits indicated an average mass of 77.7 ± 35.7 g, 12 ± 7.2 seeds per fruit, average pulp yield of 44.1 ± 8.5%, soluble solids between 11.0 oBrix and 33.0 oBrix and pH between 3.3 and 6.4. The icozeiro has a low medium size, being characterized as a shrubby plant, resistant to the edaphoclimatic weather of the region, remaining green, producing flowers and fruits in periods of drought. With regards to fruits, they presented aspects that are compatible with the requirements for industrial processing and fresh consumption in the domestic consumer market, which does not impede studies about their processing. Considering results presented and the domestic market, fresh consumption can be advantageous.

Effect of plant growth regulators on yield and yield attributing characteristics of Mango (Mangifera indica L.) cv. Dashehari

The present investigation entitled “Effect of plant growth regulators on yield and yield attributing characteristics of mango (Mangifera indica L.) cv. Dashehari” was carried out at the instructional Farm, Dept. of Horticulture, College of Agriculture, IGKV, Raipur (C.G) during the year 2017-18 employing Randomized Block Design with three replications. Three levels of NAA i.e., 15, 25 and 35 ppm, three levels of GA3 i.e. 15, 25 and 35 ppm and three levels of 2, 4-D i.e. 15, 25 and 35 ppm were sprayed at pea and marble stage of fruit development. All the treatments significantly influenced the number of fruits retained at pea, marble and harvesting stage of fruit growth and development as compared to the control. Foliar application of 35 ppm GA3 at pea and marble stage of fruit development increased number of fruits (880.49) as well as total yield (135.46 kg/plant). Physical characters of fruit viz., Fruit Length (11.65cm) and width of fruits (6.82cm), average fruit weight (177.84g), volume (173.63g) and pulp weight (130.41g) were also improved with the foliar application of 35 ppm GA3. While, stone weight (25.39g) and peel weight (19.02g) was reduced with the foliar application of 35 ppm NAA and 25 ppm foliar application of 2, 4-D. Among the different concentrations of plant growth regulators; the foliar application of 35 ppm NAA, 35 ppm GA3, 35 ppm 2, 4-D were found to be optimum concentration by which yield and yield attributing characteristics of fruits can be significantly influenced.

English

The species Elaeocarpus serratus is widely used as an ornamental tree and their fruits are still little explored as food. Thus, the objectives of this research were to determine the physical, chemical and antimicrobial properties of E. serratus fruit in order to evaluate its food potential. Therefore, this study evaluated the physical and chemical composition and the antimicrobial activity of E. serratus fruit. The biometry revealed an average pulp yield of 82.16%. The physical and chemical characteristics of the E. serratus fruit showed that the pulp has pH 2.84 and has a higher content of moisture and crude fiber. The determination of bioactive compounds showed that E. serratus fruit presented a good source of flavonoids, condensed tannins, carotenoids and Vitamin C. In the chromatographic analyses, the presence of β-amirin was observed as the major compound by gas chromatography. Among the main phenolic compounds, the presence of kaempferol and quercetin in the liquid chromatography method was evidenced. Additionally, ethanolic extract from E. serratus fruit showed antimicrobial activity against Bacillus cereus, Escherichia coli, Salmonella cholaresuis, Staphylococcus aureus and Xanthomonas campestris. Key words: Antimicrobial, ceylon olive, food science, functional food, phytochemistry.

Optimization of the blanching time and temperature in the manufacture of Hass avocado pulp using low quality discarded fruits

Abstract In Peru, approximately 20% of the production of avocado var. Hass is discarded due to its low quality, and sold at low prices in local markets. The aim of this study was to optimize the blanching time and temperature to produce avocado pulp, using low quality discarded fruits as the raw material. The process was optimized using Response Surface Methodology with a 22 central composite rotational design (R2 ≥ 0.75; p < 0.05). The independent variables studied were the blanching time (0, 1.5, 5, 8.5, 10 min) and temperature (65, 68, 75, 82, 85 °C), where the avocados were blanched by immersion (with peel), and the pulp extracted, processed, vacuum sealed (0.035 MPa) and stored under refrigeration at 5 °C for 49 days. The low quality discarded avocados were shown to be ideal for pulping, since 98% of the fruits had an oil content below 15% with an average pulp yield of 79.23%. The results indicated that longer blanching times and higher temperatures of above 5 min and 75 °C, respectively, retained the green colour and increased the brightness of the pulp, avoiding enzymatic browning. In addition, the increase in both contributed to the stability of the product acidity and pH level, extending its shelf life. However, in the sensory analysis, the pulp submitted to temperatures above 82 °C obtained the lowest scores for taste, odour and general acceptance due to the presence of a bitter taste and unpleasant odours in the pulp. The central point trials (5 min; 75 °C) presented the best scores for the independent variables such as colour, taste, odour and sensory texture, also showing good physicochemical stability with a shelf life of 37 days.

MORPHOLOGICAL DISSIMILARITY AMONG MANGABEIRA TREE POPULATIONS FROM AMAPÁ AND PARAÍBA, BRAZIL

ABSTRACT Mangabeira fruits are collected from native populations under anthropic pressure. It is therefore essential to obtain morphogenetic information to genetically improve populations, thereby preventing genetic erosion. This research was carried out in the state Amapá and aimed to verify the morphological dissimilarity between two populations, one composed of 36 native progenies and one of eight progenies from Paraiba, outlined in lattices with two replications and six plants per part. The evaluated characteristics were: agronomic value (VA), treetop circumference (CCP), plant height (ALP), estimated number of fruits per plant (NEF), fruit color (COF), average weight of 10 fruits (PMF), fruit diameter (DF), average pulp weight of ten fruits (PMP), average length of 10 fruits (CMF), average number of seeds of 10 fruits (NMS). Our results indicate that the phenotype was mainly determined by responses to environmental changes; in the correlations, inherent fruit characteristics (weight, size, and color) did not affect the VA, while biometric characters influenced VA values. Higher plants presented larger fruits and a larger diameter, bigger quantities, there is also apparent contrast, with a larger amount of smaller size; the populations are dissimilar, indicating the possibility of obtaining of diverging superior segregating.

INFLUENCE OF IRRIGATION AND POTASSIUM FERTILIZATION ON THE PRODUCTION AND QUALITY OF BANANA FRUIT IN BRASÍLIA

The present work aimed to evaluate quantitative and qualitative aspects of the initial productivity of the ‘BRS Tropical’ banana under different levels of potassium fertilization and irrigation volumes. The tests were arranged in four randomized blocks, which were consisted of a 5x5 factorial design, in slit-plot design. These plots were formed by fve different applied volumes of water in liters per pit (1090 – 2177 – 4300 – 6540 – 8720), which were equivalent to the amount of irrigation of water of 121 mm, 242 mm, 478 mm, 727 mm and 969 mm regarding the range of 9 m2 for each pit. The subplots were formed by fve levels of potassium in Kg.ha-1 (0 – 167 – 334 – 500 – 667). Both volumes of irrigation and levels of potassium were provided during the years of 2013 and 2014. The variables analyzed were for productivity, number of bunches per ha, number of hands per bunches, number of bananas per bunch, number of bananas per hand, average fruit weight, average length and diameter of the banana, the ratio between diameter and length and average pulp consistency. The doses of 500 Kg.ha-1 of K2O and 6,540 liters of water per pit provided the highest productivity (11,752 Kg.ha-1). The volumes of water were only statistically signifcant to the mass of fruit, as well as its length and diameter. The potassium application required caution, because excessive doses of potassium are harmful to productivity and quality of the fruit.

Variation of chemical characteristics and pulpability of dhaincha (Sesbania bispinosa) on location

Dhaincha ( Sesbania bispinosa ) is a crop generally cultivated for improving soil quality. Due to the lack of forest worldwide, alternative source of raw materials for cellulose industries is the main concern today. In this investigation dhaincha samples were collected from 21 accessions of different districts of the country in order to study variation of chemical characteristics and its pulpability. The lignin, pentosan and α –cellulose content were varied from 21 to 23%, from 16 to 18% and from 38 to 43%, respectively. The highest and lowest α –cellulose content were found in two location of Mymensngh district. There was no correlation was found among the district. Therefore, pulping of dhaincha from selected seven districts was carried out in kraft process at the conditions of 18% active alkali at 170 o C for 2 h. But the pulping properties did not show any mentionable distinction for place variation. Average pulp yield is 42.9% with kappa number 11. The highest brightness 85% ISO was reached with D 0 E p D 1 bleaching. The papermaking properties were very close to the conventional raw materials used in Bangladesh. Therefore, dhaincha can be used as a raw material for pulp production in Bangladesh.

REPEATABILITY OF PHYSICAL AND CHEMICAL CHARACTERISTICS IN PEQUI FRUITS

ABSTRACT The aim of this study was to estimate the effects of populations and mother trees over some characteristics on pequi (Caryocar brasiliense Camb.) fruits as well as their repeatability coefficient. Data came from two populations with 15 mother trees each, covering three years. The following physical and chemical characteristics were evaluated: total fruit weight; external mesocarp weight; number of putamens per fruit; total weight of putamens; total and average pulp weight; and proportion of the weight of lipids and proteins in relation to pulp weight. Analysis of variance was performed using a nested design model. The effects of mother trees within populations were highly significant for all variables under study, while the effects of populations were not for any characteristic, showing that for populations and mother trees, efforts must be focused on the number of mother trees per population rather than on populations. The estimated repeatability coefficients showed high genetic control for total fruit weight; external mesocarp weight; average weight of putamens; average pulp weight; and proportion of the weight of lipids in relation to pulp weight. Therefore, the expression of these characteristics on descendants, by cloning selected mother trees, is likely to be effective.

Neurovascular Island Flap for Pulp and Nail Augmentation in Hypoplastic Thumb Duplication Reconstruction

Objective: Pulp and nail asymmetry is commonly seen in thumb duplication condition, particularly when both digits are significantly hypoplastic. Conventional or modified Bilhaut-Cloquet procedure can help to restore the symmetry but very often results in a major dorsal scar leading to cosmetic imperfection. The authors introduced a neurovascular island flap for pulp and nail augmentation, and combined with a dorsally based skin flap approach, to improve the aesthetic result in thumb duplication reconstruction. Materials and Methods: Eight patients, including 1 Wassel type II, 1 Wassel type III, and 6 Wassel type IV, were operated on between 2002 and 2010. The contralateral thumbs are all normal. All patients had significant hypoplasia and asymmetry of the pulp and nail of the planned retained digit. The average age of operation was 12 months (range, 8-15 months). A dorsally based skin flap centered on the site of bifurcation was raised for exposure and dissection of the abnormal structures. A neurovascular island flap, including part of the pulp tissue, nail bed, with or without the associated phalangeal bone, was raised from the planned ablated digit based on its single neurovascular bundle. After the standard procedure of ablation, ligament, and musculature reconstruction, with or without realignment osteotomy, the island flap was transferred to the proper digit with meticulous repair of the nail bed, nail fold, and pulp tissue using fine sutures under magnification with operating microscope. All patients were followed up with to monitor the aesthetic, functional, and radiological outcome. The average follow-up was 80 months (range, 25-120 months). An aesthetic scoring system was proposed to assess the cosmetic results of the thumb duplication reconstruction. Results: All flaps survived, with transient intraoperative ischemia of the transferred pulp in 1 case. The major portion of the surgical scar lied toward the volar aspect of the thumb, leaving the cosmetic dorsal aspect relatively intact. Pulp and nail fold symmetry was improved in all cases. The nail width discrepancy reduced from 25.2% preoperatively to 4.6% at final follow-up. The hypoplastic appearance of the pulp was improved in all cases. The pulp circumference was comparable with the contralateral normal thumb, with average pulp circumference discrepancy of 6.8% (range, 1.7%-13.0%) at final follow-up. Nail ridges were moderate in 2 early cases, minimal in 3 cases, and inconspicuous in 3 cases. Surgical scar was not obvious in all but 1 case. The proposed aesthetic scoring system was able to assess and highlight the cosmetic aspect of the outcome and correlated well with the parents’ satisfaction. Conclusions: In selected cases of thumb duplication with significant pulp hypoplasia and nail asymmetry, the neurovascular pulp and nail island flap is a safe and effective mean to restore symmetry for better aesthetic improvement.

Optimizing postharvest methyl bromide treatments to control spotted wing drosophila, Drosophila suzukii, in sweet cherries from Western USA

Methyl bromide (MB) chamber fumigations were evaluated for postharvest control of spotted wing drosophila (SWD), Drosophila suzukii (Matsumura) (Diptera: Drosophilidae), in fresh sweet cherry exports from Western USA. Sweet cherries were infested with SWD, incubated to maximize numbers of the most MB-tolerant specimens (ca. 60 to 108-h old at fumigation, 88% 3rd & 2nd instars), buried amongst uninfested fruit in bins consistent with commercial practice, cooled to an average pulp temperature ≥ 8.3 °C, and then fumigated in a chamber. Treatment efficacy was diagnosed by the percentage of survivors emerging as adults from fumigated cherries relative to that from non-fumigated control cherries. A kinetic model of sorption was developed based on the measurement of MB and how calculated exposures varied across the fumigation trials. The model describes how to manipulate the applied MB dose, fumigation duration, and the load factor so that the resultant exposure is adequate for SWD control across various pulp temperatures when cherries are fumigated in wooden versus plastic bins. Results are discussed in the context of graduation toward optimized quarantine fumigation schedules for control of SWD, which will promote more strategic technical and economic Quarantine Pre-shipment (QPS) use of MB.

Preliminary results of fruit selection and induced parthenocarpy of mabolo (Diospyros blancoi A. DC.)

The fruits of Diospyros blancoi A. DC., commonly known as velvet apple or mabolo, vary greatly in size. The aims of our study are to clarify the feasibility of large fruit selection and investigate the parthenocarpic nature of mabolo in order to better understand the potential applicability of mabolo in large and seedless fruit production. To conduct an initial selection for large fruits in Taiwan, three individuals (code named SYD, KKN, and YKC) with an average fruit size of more than 200 g were selected. The largest fruits were collected from SYD, the fruit had an average weight of 218.6 ± 61.9 g and an average pulp weight of 193.8 ± 55.1 g (after deducting the weight of seeds). These results were significantly different from those recorded for the entire population, which had an average fruit weight of 103.9 ± 34.0 g and pulp weight of 78.6 ± 29.1 g (after deducting the weight of seeds). As in persimmons (Diospyros kaki Thunb.), parthenocarpic seedless fruits can also be obtained in D. blancoi through manipulation. Parthenocarpic seedless fruits were induced in SYD using either bagging or the stigma removal method. The fruit-set rate and average fruit weights were 49 % and 122.6 ± 24.7 g, and 76 % and 109.3 ± 18.7 g for bagging and the stigma removal method, respectively. SYD fruits had not only fewer seeds and lesser seed weight but also the highest average pulp weight compared to the other two selections, showing that D. blancoi has good parthenocarpy nature and SYD has the best large fruit characteristic for potential commercialization of mabolo.

Numerical Simulations of Two-Phase Flow in a Self-Aerated Flotation Machine and Kinetics Modeling

A new boundary condition treatment has been devised for two-phase flow numerical simulations in a self-aerated minerals flotation machine and applied to a Wemco 0.8 m3 pilot cell. Airflow rate is not specified a priori but is predicted by the simulations as well as power consumption. Time-dependent simulations of two-phase flow in flotation machines are essential to understanding flow behavior and physics in self-aerated machines such as the Wemco machines. In this paper, simulations have been conducted for three different uniform bubble sizes (db = 0.5, 0.7 and 1.0 mm) to study the effects of bubble size on air holdup and hydrodynamics in Wemco pilot cells. Moreover, a computational fluid dynamics (CFD)-based flotation model has been developed to predict the pulp recovery rate of minerals from a flotation cell for different bubble sizes, different particle sizes and particle size distribution. The model uses a first-order rate equation, where models for probabilities of collision, adhesion and stabilization and collisions frequency estimated by Zaitchik-2010 model are used for the calculation of rate constant. Spatial distributions of dissipation rate and air volume fraction (also called void fraction) determined by the two-phase simulations are the input for the flotation kinetics model. The average pulp recovery rate has been calculated locally for different uniform bubble and particle diameters. The CFD-based flotation kinetics model is also used to predict pulp recovery rate in the presence of particle size distribution. Particle number density pdf and the data generated for single particle size are used to compute the recovery rate for a specific mean particle diameter. Our computational model gives a figure of merit for the recovery rate of a flotation machine, and as such can be used to assess incremental design improvements as well as design of new machines.

Caracterização de plantas e de frutos de araticunzeiro (Annona crassiflora Mart.) nativos no Cerrado Matogrossense

O araticunzeiro (Annona crassiflora Mart - Annonaceae) é uma frutífera nativa do cerrado brasileiro que necessita de estudos visando à geração de dados para subsidiar pesquisas relativas à sua domesticação. Com o presente trabalho, objetivou-se estudar uma população de araticunzeiro em relação ao diâmetro do caule e altura das plantas, à produção e às características físicas e químicas de frutos. Nas plantas, mensuraram-se diâmetro do caule, altura e produção de frutos. Nos frutos, analisaram-se os diâmetros longitudinal (DL) e transversal (DT), a relação DL/DT, as massas do fruto, da casca, da semente e da polpa, e calculou-se o rendimento de polpa. Na polpa, efetuaram-se as determinações de sólidos solúveis (SS), acidez titulável (AT), relação SS/AT, pH e umidade. As árvores possuem diâmetro do caule de 10,4±3,1 cm e altura de 3,7±0,7m com produção média de 6,0±3,6 frutos por planta. Em média, os frutos possuem DL de 14,2±1,4, DT de 15,2±2,2 e relação DL/DT de 0,9±0,1; possuem massa média de 1.565,5±508,5g, tendo as massas da casca, das sementes e da polpa médias de 662,2±198,2g, 179,8±66,2g e 723,5±276,7g, respectivamente, com rendimento médio de polpa igual a 45,9±4,7% do fruto. Na polpa, constataram-se médias de SS de 17,60±1,86 ºBrix, AT de 0,37±0,11% de ácido málico, relação SS/AT de 52,23±17,64, pH de 4,45±0,23 e umidade média igual a 74,3±2,86%. O araticunzeiro possui características físicas e químicas que o tornam uma alternativa para a fruticultura nativa brasileira.

Chemical Composition and Pulp Properties of Abaca (Musa textilis Née) cv. Inosa Harvested at Different Stages of Stalk Maturity

Given the increasing global demand for pulp, there is a need to look into the prospects of increasing fiber production and shortening the harvesting cycle of abaca without sacrificing the quality of fibers for pulp production. This study investigated the chemical and pulp properties of abaca cv. Inosa fibers harvested at different stages of stalk maturity to determine their suitability for pulp and paper production. Fibers obtained from 8-10-month-old (immature) abaca cv. Inosa possessed the desirable chemical properties for pulping, namely; low lignin and ash content, high alpha-cellulose, holocellulose and hemi- cellulose contents; which are comparable with those obtained from intermediate and mature stalks. The average pulp yield, Kappa number, viscosity, tear index and breaking length of pulps from immature stalks were already comparable with those of mature fibers and were even higher than the mature fibers of Linawaan and Laylay cultivars. Fibers of abaca cv. Inosa obtained from immature stalks were thus, found suitable for pulp and paper production.