Peel Mass Research Articles

Sustainable innovations in postharvest conservation of passion fruit

The study aimed to evaluate the post-harvest quality of sour passion fruit using carnauba wax, cassava starch, and avocado seed extract coatings. The experiments were conducted in randomized blocks with five replications and two fruits per experimental unit. Two coatings associated with biofungicide were used. The carnauba wax treatment consisted of Control: fruits coated with pure carnauba wax, Wax and Extract 1:1, Wax and Extract 1:3, and fruits coated with avocado seed extract solution. The cassava starch treatment consisted of Control: fruits coated with avocado seed extract solution, fruits coated with pure cassava starch, Starch and Extract 1:1, Starch and Extract 1:3, and subplots consisting of six periods: 00, 03, 06, 09, 12, 15 conservation days, for both experiments. Fresh matter mass loss, peel color, longitudinal and transversal diameter, fruit mass, peel mass, pulp mass, total soluble solids, total titratable acidity, ratio, and pH were evaluated. Coatings, individually or in combination, influenced physicochemical attributes, presenting more adequate values for peel thickness and citric acid percentage acid in the juice. The results highlight the influence of storage time on fruit characteristics, emphasizing the need to assess specific approaches to optimize post-harvest conservation.

Analysis and Modeling of the Onion Peeling Process in the Blowing Compressed Air Method

This paper presents the relationship between the efficiency of the process of onion peeling and the amount of waste generated in the process. The research was carried out on a pilot test stand for onion peeling. The process variables were the value of the compressed air pressure (p) and the value of the flow opening time through the control valve (t). The experiment took into account the influence of the onion diameter (d0) and its hardness (H). The obtained results were subjected to statistical analysis. Standard deviations were of the percentage loss of onion mass in the form of the peel removed in the onion peeling process in relation to the obtained average values. Tukey’s multiple comparison test was performed in order to identify the importance of individual process variables on the final effect of onion peeling. This was the basis for the development of a predictive model in the form of a non-linear regression Mp = f(p,t,d0,H), which is a mathematical description of the onion peeling process. Finally, the response surface area of the relationship between analyzed variables was determined. The results of research show that the peeling efficiency of the onion and waste of peel mass depend on the compressed air pressure. Extending the onion blowing time does not improve the process efficiency, while the hardness and size of the onion are irrelevant to the process.

Artificial intelligence models for yield efficiency optimization, prediction, and production scalability of essential oil extraction processes from citrus fruit exocarps

Introduction: Excessive demand, environmental problems, and shortages in market-leader countries have led the citrus (essential) oil market price to drift to unprecedented high levels with negative implications for citrus oil-dependent secondary industries. However, the high price conditions have promoted market incentives for the incorporation of new small-scale suppliers as a short-term supply solution for the market. Essential oil chemical extraction via steam distillation is a valuable option for these new suppliers at a lab and small-scale production level. Nevertheless, mass-scaling production requires prediction tools for better large-scale control of outputs.Methods: This study provides an intelligent model based on a multi-layer perceptron (MLP) artificial neural network (ANN) for developing a highly reliable numerical dependency between the chemical extraction output from essential oil steam distillation processes (output vector) and orange peel mass loading (input vector). In a data pool of 25 extraction experiments, 14 output–input pairs were the in training set, 6 in the testing set, and 5 cross-compared the model’s accuracy with traditional numerical approaches.Results and Discussion: After varying the number of nodes in the hidden layer, a 1–9–1 MLP topology best optimizes the statistical parameters (coefficient of determination (R2) and mean square error) of the testing set, achieving a precision of nearly 97.6%. Our model can capture non-linearity behavior when scaling-up production output for mass production processes, thus providing a viable answer for the scalability issue with a state-of-the-art computational tool for planning, management, and mass production of citrus essential oils.

Fruit yield and quality traits of Pakistani cultivars of Citrus sinensis Osbeck in core area of Production

Citrus is an important table fruit having refreshing taste and rich source of vitamin C. Citrus sinensis is an important species of citrus which is being consumed by large masses due to its peculiar taste and high sugar content and early availability in the fruit market. A study was conducted to identify the potential varieties of this commercial species. Commercial varieties were evaluated for yield related and biochemical traits. It was identified that commercial variety “Salustiana” had the fruit of largest mass, least number of seed, juice mass, volume and peel mass. Disease free nursery may be developed to commercial this variety in core area of Punjab and may also be used in molecular studies.

Hydroethanolic Extract of Grape Peel from Vitis labrusca Winemaking Waste: Antinociceptive and Anti-Inflammatory Activities.

SUMMARYResearch backgroundExtracts from grape pomace, including the wine, show many biological effects such as antioxidant and anti-inflammatory activities. Unfortunately, winemakers discard the bagasse, so the waste is not exploited, although it contains bioactive compounds with antioxidant and anti-inflammatory properties. The work aims to analyze the hydroethanolic extract of peels from Vitis labrusca agro-industrial waste and to evaluate its antinociceptive and anti-inflammatory properties. This study is relevant for reusing a residue and adding value to the grape economic chain.Experimental approachA representative sample of pomace was obtained and the peels were used to produce the extract. The phenolic compounds were determined by mass spectrometry in multiple reaction monitoring mode and Folin-Ciocalteu colorimetric method, using gallic acid as standard. The biological analyses were carried out using mice orally treated with crude extract at doses of 30, 100 and 300 mg/kg. We evaluated mechanical hyperalgesia by the von Frey method, thermal heat hyperalgesia using a hot plate at 55 °C, paw edema using a pachymeter, and neutrophil recruitment by measurement of myeloperoxidase activity. The nephrotoxicity and hepatotoxicity were evaluated by biochemical analyses using blood samples that were collected after the Vitis labrusca administration.Results and conclusionsIn all wet winemaking residues peel mass fraction was 75%, and in dry residues 59%. We identified nine anthocyanins (3-O-glucosides: peonidin, delphinidin, petunidin and malvidin; 3-p-coumaroyl-glucosides: cyanidin, peonidin, petunidin and malvidin, and malvidin-3,5-diglucoside), five flavonoids (apigenin-7-glucoside, luteolin-7-glucoside, quercetin-3-galactoside, isorhamnetin-3-glucoside and myricetin-3-rutinoside), and mass fraction of phenolic compounds, expressed as gallic acid equivalents, was 26.62 mg/g. In vivo assays showed that Vitis labrusca extract at mass fractions 100 and 300 mg/kg reduced carrageenan-induced mechanical and thermal hyperalgesia, 50% of the paw edema, and neutrophil recruitment. In addition, there were no indications of nephrotoxicity and hepatotoxicity. Our extract obtained from winemaking residue has analgesic and anti-inflammatory properties, related at least in part to the presence of phenolic compounds, and it is not toxic to renal and hepatic tissues.Novelty and scientific contributionThis bio-product can be used as an alternative to synthetic anti-inflammatory agents with the same pharmacological potential and fewer side effects. We demonstrated that Vitis labrusca winemaking waste can be used for the production of antinociceptive and anti-inflammatory products (nutraceutical, pharmaceutical and cosmetics) without toxicity, contributing to the environmental economy.

Cladode Pruning Affects Yield and Fruit Quality of ‘Roja Lisa’ Cactus Pear [Opuntia ficus-indica (L.) Mill.]: A Preliminary Study

Aims: This study assessed the initial effect of experimental pruning (EP) or grower’s pruning (GP) of cactus pear fruiting cladodes on fruit yield (FY), fruit size distribution (FSD), and fruit quality (FQ) at harvest and after storage.
 Study Design: Treatments were arranged in a completely randomized design with eight or ten replicates, with a single plant as replicate, for EP or GP, respectively.
 Place and Duration of Study: The experiment was set up in a drip-irrigated commercial orchard of ‘Roja Lisa’ cactus pear [O. ficus-indica (L.) Mill.] plants located at Santa Fe, Jerez, Zacatecas, México, from February to August 2006.
 Methodology: The EP considered two agronomic practices: 1) exposing the center of each plant while eliminating unproductive cladodes and those shading other cladodes and 2) concentrating fruiting cladodes in the outer part of the plants. The GP randomly eliminated some cladodes from the central part and around the plants only. Treatments were arranged in a completely randomized design with eight or ten replicates, with a single plant as replicate, for EP or GP, respectively. The response variables were: FY, FSD, and FQ at harvest and after storage. The FQ attributes were: mean fruit mass (MFM), flesh firmness (FF), total soluble solids concentration, pulp and peel mass, dry matter concentration, and fruit water loss (FWL) during storage.
 Results: EP increased MFM by 42% over GP and produced 15% more marketable fruit (fruit equatorial diameter from 5.0 to 7.0 cm), but FY was reduced by 39%. The FF was higher in EP fruit than GP fruit after storage. The other FQ attributes were similar in both pruning treatments, both at harvest and after three weeks at room temperature. The FWL was also similar under both pruning systems. More targeted pruning has the potential to increase the productivity of cactus pear orchards.
 Conclusion: Experimental pruning increased fruit size and the percentage of commercial fruit, but reduced both overall and commercial fruit yields. After three-week storage at room temperature, flesh firmness remained greater in EP fruit. Fruit water loss was not influenced by pruning treatments during the storage.

Genetic diversity of the ease of peeling in mandarins

The ease of peeling is an important fruit quality trait for fresh-eating citrus, particularly mandarins. In the practice of hand peeling of citrus fruits, both the peel-pulp adherence and peel resistance to penetration are relevant to the ease of peeling. In this study, we first elaborated an easy apparatus that facilitated precise quantification of peel-pulp adherence and peel resistance to penetration. Through measuring mandarins, oranges, pummelos and lemons that each included 10 varieties, the ascending order of the peel-pulp adherence was mandarin < orange < lemon < pummelo, and that of the peel resistance to penetration was mandarin < orange < pummelo < lemon. Eighty mandarin varieties from National Citrus Germplasm Repository, China exhibited great diversities of peel-pulp adherence and peel resistance to penetration. The hierarchical clustering analysis based on these two properties classified these mandarins into two major clades, representing 72 easy-peeling and 8 hard-peeling mandarins, and the easy-peeling mandarins were further divided into two subclades, namely, 42 very easy-peeling and 30 moderately easy-peeling subclades. The orange, grapefruit or Hassaku ancestral origin may contribute to the property of hard peeling in some moderately easy-peeling and hard-peeling mandarins. Some representative easy-peeling mandarins had loose albedo with great aerial spaces. The correlation analysis demonstrated that peel thickness was relevant to peel firmness but not the peel resistance to penetration, and peel mass per unit area but not peel density was relevant to peel firmness. Moreover, the peel-pulp adherence and peel resistance to penetration were positively correlated, implying a common mechanism controlling the two properties of the ease of peeling.

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.

Supplemental irrigation improves water-use efficiency, yield, and some fruit quality attributes of ‘Dalia Roja’ cactus pear

Cactus pear is grown mainly under rain-fed conditions in marginal semi-arid and arid highlands of central and north-central Mexico. Drip irrigation may increase fruit yield ~3.5-fold. However, the effects of supplemental irrigation (SI) on preharvest growth and water saving have not been assessed previously. The objective of this study was to determine the possibility of saving water and improving water-use efficiency (WUE) in 'Dalia Roja' cactus pear, without adverse effects on fruit yield (FY) and fruit quality (FQ). Irrigation treatments (IT) were as follows: non-irrigated (NI) as control, supplemental irrigation (SI), and full irrigation (FI). Treatments were arranged in a completely randomized design with three replicates. The response variables were irrigation water applied (IWA), WUE, FY, fruit size distribution (FSD), and FQ. The following FQ determinations were made: mean fruit mass (MFM), flesh firmness (FF), pulp and peel mass, total soluble solids concentration (TSSC), and dry matter concentration (DMC) of fruit. The experiment was conducted in Zacatecas, Mexico. At harvest, SI saved ~52% of IWA, increased the efficiency of IWA by ~1.4-fold, but reduced FY by 12.9% compared to FI. Over 70% of the fruit produced by FI and SI plants was most marketable (categories 1 and 2), while NI plants produced only 28% category 2 fruits. The quality indicators FF and pulp-to-peel ratio were similar among IT, while NI fruit had the highest TSSC and DMC and the lowest MFM. SI produced similar responses to FI while saving irrigation water and enhancing FY, FSD, and MFM, but TSSC and DMC were reduced. Nevertheless, SI has potential for growing cactus pear in this region and similar production zones around the world where water availability is limited.

Yield and Physical Quality of the Yellow Passion Fruit under Spacing within Plants and Water Salinity

Aims: The aim of this work was to evaluate the yield and the physical quality of the yellow passion fruit accession ‘Guinezinho’ as a function of the within-row plant spacing, with saline irrigation water in consecutive growing seasons.&#x0D; Study Design: The experiment was arranged in randomized blocks, with four replicates and 12 plants per parcel, in a 4 x 2 factorial arrangement, referring to the spacing in the planting lines of 3, 6, 9 and 12 m, and two consecutive growing seasons.&#x0D; Place and Duration of Study: The experiment was developed in the municipality of Coronel Ezequiel, Rio Grande do Norte state, Brazil, within the months of April 2013 and October 2014.&#x0D; Methodology: The seedings were transplanted in the spacings of 3, 6, 9 and 12 m, and distant 2 m within lines according to the treatments; they were conducted in a vertical shoot position (VSP) training system, and daily irrigated during the arid period with saline water (ECiw = 3.4 dS m-1). The following characteristics were evaluated: fruit yield, fruit mass, longitudinal and transversal fruit diameter, pulp yield, peel mass and peel thickness.&#x0D; Results: The interaction between spacing and growing season exercised a significant effect on the fruit yield, longitudinal fruit diameter, pulp yield, thickness and mass of the peel (P = .05). The variables transversal diameter and fruit mass only varied within the growing seasons (P = .05). The plants cultivated in the 3 m spacing were the most productive in the two seasons, with 23.7 and 36.3 t ha-1, in the first and second seasons, respectively.&#x0D; Conclusion: The highest yield of the yellow passion fruit accession ‘Guinezinho’ was obtained in the smaller plant spacing in the lines. Except for the pulp yield, the yield and physical quality of the fruits were superior in the second growing season. The irrigation with highly saline water, in this type of soil, did not compromise the productive ability of the passion fruit accession ‘Guinezinho’.

Agronomic performance of 'Valência' orange combined with 13 rootstocks in the state of Rio Grande do Sul, Brazil

Abstract: The objective of this work was to evaluate the agronomic performance of 'Valência' sweet orange (Citrus sinensis) tree, in combination with 13 rootstocks cultivated in soil and climate conditions of the Brazilian state of Rio Grande do Sul. The following agronomic variables were evaluated: scion height and volume, plant production, production efficiency, productivity, fruit diameter, fruit mass, peel mass, juice yield, soluble solids content, titratable acidity, soluble solids:acidity ratio, ascorbic acid, peel color, antioxidant capacity, and phenolic compounds. A randomized complete block experimental design was used, with three replicates and nine plants per plot, in a two-factor arrangement (13 rootstocks and the 2015 and 2016 harvests). The following rootstocks stood out: TSKC × TRDP-023 for its juice yield (54.0 and 51.7%), soluble solids:acidity ratio (8.66 and 6.99), and ascorbic acid (49.3 and 51 mg 100 g-1); and the citrandarin 'San Diego', for its higher phenolic-compound content (106.4 and 74.9 100 g-1 gallic acid), coloration (76.2 and 75.9 hº), and ascorbic acid (42.2 and 44.7 mg 100 g-1). The TSKC × TRDP-026 and TSKC × CTQT1434-004 rootstocks induce canopy formation and productive precocity in 'Valência' orange trees grown in the southern region of the state of Rio Grande do Sul state, in the first few years of growth.

Características físicas e químicas de acessos de umbuzeiros (Spondias tuberosa Arr. Cam)

The caatinga is a biome rich in biodiversity occupying an area of about 11% of the national territory, in asemi-arid climate, with typical Brazilian xerophytic vegetation, and. The umbu tree (Spondias tuberosa&nbsp;Arr. Cam.) is an endemic species of this type of vegetation that presents great economic importance, as an alternative source of income, especially in drought periods.Thus, this work had the objective to characterize, physically and chemically, the umbu fruits. Ten fresh fruits of umbu were used, from 10 trees in five municipalities in the state of Bahia, Brazil (Anagé, Belo Campo, Brumado, Caraíbas and Macarani), totaling 100 fruits per municipality. The evaluations were carried out at the Plant Breeding and Production Laboratory of the State University of Southwest of Bahia in March 2016. The following biometric characteristics were analyzed: length, diameter, fruit and endocarp thickness, fruit mass, peel mass, pulp mass, endocarp mass, and also total soluble solids, pH and titratable total acidity. Data of independent samples were submitted to analysis of variance and the means were compared by the t test, at 5% probability. Variability of the physical and chemical characteristics was observed. The fruits from the municipality of Macarani stand out in relation to length, width, fruit thickness, total fruit mass, peel mass, pulp yield, pH and soluble solids which confer desirable quality for&nbsp;in natura&nbsp;consumption and industrial processing.

Effect of time and storage conditions on the physical and physico-chemical characteristics of the pulp of yellow and purple passion fruit

The aim of this study was evaluate the physical and physico-chemical characteristics of extracted fruit pulp of passion fruit with different skin color (yellow, light and dark purple) under refrigeration temperatures and storage times. The extracted pulp of passion fruit was stored at different temperatures: 10 °C, 25 °C; - 30 °C and - 80 °C and at four different storage periods: 0; 10; 20 and 30 days. The following physical and physico-chemical characteristics of the fruit were evaluated: color of fruit peel, fruit weight, diameter, length and width of the fruit, peel thickness, peel mass, pulp mass, pulp color, juice yield, pH, soluble solids, titratable acidity and ratio. The physical and physico-chemical results indicate that all the passion fruit pulp, in natura as well as refrigerated, presented values in conformity to the identity and quality standards. The coloration of the fruit peel influenced the preservation of pulp color during the storage period and conditions. Purple fruits showed no change in the color of the pulp, even under different conservation procedures. The passion fruit pulp can be stored up to 30 days while preserving the physical and physico-chemical characteristics, similar to the pulp in natura.

English

The biological function of fruiting is to produce and disseminate seeds. However, seedless fruits have some advantages, including the ease of consumption and the increased added value of the final product and fruit quality. The present study aimed to evaluate the combined use of gibberellic acid (GA3) and hand pollination with Annona squamosa pollen grains on fruit set and the physical and chemical parameters of 'Gefner' custard apple fruits. The experiment was performed in a commercial custard apple orchard in a randomized design, with 11 treatments, four replications and five plants per parcel. The treatments applied were as follows: (1) hand pollination with the pollen of sugar apple (HPPSA) (control); (2) HPPSA + 500 ppm GA3 applied on the 1st week after anthesis (WAA); (3) HPPSA + 500 ppm GA3 applied on the 1st and 3rd WAA; (4) HPPSA + 500 ppm GA3 applied on the 1st, 3rd and 5th WAA; (5) HPPSA + 1,000 ppm GA3 applied on the 1st WAA; (6) HPPSA + 1,000 ppm GA3 applied on the 1st and 3rd WAA; (7) HPPSA + 1,000 ppm GA3 applied on the 1st, 3rd and 5th WAA; (8) 1,000 ppm GA3 applied at flowering and on the 1st and 3rd WAA; (9) 1,000 ppm GA3 applied at flowering and on the 1st, 3rd and 5th WAA; (10) 1,500 ppm GA3 applied at flowering and on the 1st and 3rd WAA, and (11) 1,500 ppm GA3 applied at flowering and on the 1st, 3rd and 5th WAA. A total of 20 plants were used. The harvest was performed at the 18th WAA. The fruit set rate, number of seeds per fruit, fruit length, fruit diameter, fruit mass, pulp mass, peel mass and fruit chemical characteristics were evaluated. The results were submitted to an analysis of variance, and the means were compared by the Tukey test (P > 0.05). A significant difference among the treatments was not observed for fruit set, presenting an average of 77% at the 18th WAA. Three applications of 500 ppm GA3 plus hand pollination induced the production of fruits with increased length, diameter and mass. Fruits produced by hand pollination alone or combined with GA3 had a lower percentage of fruit peel. The use of 1,500 ppm of gibberellic acid is efficient for producing seedless fruits in custard apple with high physical and chemical parameters.

Potato peeling costreams as raw materials for biopolymer film preparation

ABSTRACTPotato peel mass is a costream produced in large quantities by the food industry. Its availability and the presence of starch (46%), pectin, and cellulose make it a potential renewable raw material for polymer products. In this study, biopolymer films were produced from potato peel mass and glycerol. High‐pressure homogenization (HPH) and HPH combined with heat treatment were investigated as pretreatment technologies before film casting. HPH‐treated potato peel mass yielded biopolymer films with similar barrier and mechanical properties as films prepared from pure potato starch, including complete impermeability to grease. Additional heat treatment of the peel mass enhanced starch gelatinization, resulting in improved barrier properties and smoother surface topography of the films. Films with similar appearance and quality were also obtained from starch‐free potato peel mass, indicating that potato fiber rich in pectin and cellulose is likewise a suitable material for biopolymer film preparation after HPH treatment. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 42862.

LEMON PEEL DEGRADATION MODELING IN THE ENZYMATIC PEELING PROCESS

ABSTRACT This work studies the optimization of the enzymatic peeling of Primofiore lemons, focusing on determining the changes that happen in the peel albedo. In this process, the conditions of temperature, time and concentration of the enzymatic preparation were determined in order to produce the maximum peel mass loss related to the best peeling efficiency. In this study, the effect of the temperature on the peeling process rate, the kinetic constants at different temperatures and the activation energy of the degradation of the peel albedo were determined.PRACTICAL APPLICATIONSThe process described in this work is applied in the peel removal technology by enzyme infusion, being one of the stages in the preparation of minimally processed lemons.

Differences in suberin content and composition between two varieties of potatoes ( Solanum tuberosum) and effect of post-harvest storage to the composition

The waterproof defence barrier of the potato ( Solanum tuberosum) tuber periderm consists of the suberized cells of phellem. The distinct polyaliphatic and polyaromatic domains of suberin have separate roles in the development of resistance to infections. The aliphatic suberin composition and changes in the amounts of peel and extractive free suberized membrane i.e. raw suberin were studied in two potato varieties, Nikola and Asterix, during post-harvest storage for one year. The amount of peel increased from 2.33 to 4.80 g/kg in yellow-skinned Nikola and from 3.50 to 5.54 g/kg in red-skinned Asterix. The raw suberin fraction accounted for 258.1 ± 16.6 mg/g in the peel of Nikola and 250.7 ± 36.3 mg/g in the peel of Asterix on average during the storage period. In addition to increase in suberin up to 6 months, the microscopic images of the peel and raw suberin indicated that the other components contributed to the peel mass increase. The CHCl 3-soluble suberin monomer fraction after methanolysis accounted for about 20% of the raw suberin in both varieties, indicating a constant ratio of suberin polyaliphatic and polyaromatic domain over the storage period. α,ω-Diacids, fatty acids and aromatic compounds were more abundant in Asterix, while ω-hydroxyacids and fatty alcohols were more abundant in Nikola (all p = 0.000). Small changes in the aliphatic monomer composition within each variety were seen during storage.

Albedo hydrolysis modelling and digestion with reused effluents in the enzymatic peeling process of grapefruits

Until now, the optimisation of enzymatic peeling of grapefruit in the reactor has been obtained as the result of the semi-qualitative effects of enzyme activity. This work is an attempt to obtain quantified data. The reuse of enzymes to reduce costs in this process is unprecedented in the literature and is the aim of the present work. The optimal conditions determined for the maximum albedo degradation were a temperature of 40.6 °C and a time of 13.1 min in an enzymatic concentration of 0.067 mL enzymatic preparation per gram of peel in each litre of citrate buffer solution. The decrease in relative enzymatic activities in reused effluents was determined, as was the increase in activity when the enzymes were purified. These increases were 15.5% for polygalacturonase and 15.4% for cellulase activity. Optimal temperature, time and the ratio between peel mass and the enzymatic preparation volume were the best conditions for obtaining good peeling efficiency. The effluents from the enzymatic peeling process of the grapefruit still contain appreciable enzymatic activity after the digestion process. Thus, reusing these effluents while maintaining peeling efficacy and a subsequent recovery of the active enzymes by ultra-filtration of the effluents is the way to improve the efficiency of the process.

Repetibilidade em características do fruto do maracujazeiro

A análise de sucessivas medições de uma característica em um grupo de indivíduos é um procedimento desejável no melhoramento genético de culturas, pois espera-se que a superioridade ou inferioridade inicial de um indivíduo em relação aos demais mantenha-se ao longo das medições. A veracidade dessa expectativa pode ser aferida pelo coeficiente de repetibilidade das características avaliadas. Os objetivos deste trabalho foram (1) determinar o coeficiente de repetibilidade pelos métodos da Análise de Variância, Componentes Principais (matriz de correlação e covariância) e Análise Estrutural das seguintes características: massa média, comprimento longitudinal, diâmetro equatorial, massa média da polpa e da casca e espessura da casca do fruto; e (2) determinar o número mínimo de avaliações para um eficiente processo de seleção de genótipos de maracujazeiro-azedo. O trabalho foi desenvolvido no Departamento de Fitotecnia da Universidade Federal de Viçosa, analisando-se 20 progênies de meios-irmãos segregantes de maracujazeiro-azedo. Observaram-se diferenças entre as estimativas dos coeficientes de repetibilidade obtidos pelo método da análise da variância e pelos métodos multivariados, havendo superioridade nas estimativas com o emprego dos últimos métodos nos programas de melhoramento do maracujazeiro-azedo. O método dos componentes principais, com base na matriz de covariância, sempre apresentou estimativas maiores, principalmente para espessura da casca e comprimento longitudinal do fruto, sendo esse método mais eficiente para a estimação do coeficiente de repetibilidade das características avaliadas. A realização de 18 medições nos frutos de maracujazeiro-azedo será suficiente para predizer o valor real dos indivíduos com 90% de acurácia no primeiro ano de produção, com relação à massa fresca do fruto, massa de polpa e casca, comprimento longitudinal e diâmetro equatorial.

PHYSICAL AND MECHANICAL PROPERTIES OF PONKAN MANDARIN APPLIED TO GRADING MACHINE

The aim of this research is to study some physical and mechanical properties of Ponkan mandarin, as promising fruits, to help the design of handling machines. The physical and mechanical properties are incorporated in the development of the grading machine as a case study. The main results in this study can be summarized in the following points: Physical properties of Ponkan mandarin fruits: diameter = 58.61 – 85.56 mm, height = 49.45 – 78.9 mm, mass = 70 - 128 g, volume = 60 - 120 cm3, projected area = 41.22 – 81.88 cm2, peel thickness = 2.18 – 3.73 mm, peel mass = 24.2 – 36.1 g, number of segments/fruit = 8 - 12, number of seeds/fruit = 4 - 9, juice volume/fruit = 23 - 34 cm3, and juice volume/fruit mass = 0.24 - 0.45 L/kg. Mechanical properties of Ponkan mandarin: The average of firmness distribution along Ponkan mandarin surface were: the maximum = 18.3 N/cm2 at the top of fruit and the minimum = 11 N/cm2 at the bottom of fruit. The deformation range increased from 2.75 - 3.09 to 8.52 - 10.02 mm by increasing loading from 1 to 5 kg. Meanwhile, the deformation range increased from 2.75 - 8.52 to 3.09 - 10.02 by increasing loading time from 15 to 60 s. Some application to grading machine is given also in the paper as a case study.