Fresh Mass Loss Research Articles

English

The desirability of minimally processed products makes the prickly pear (Opuntia ficus indica (L.) Mill) an option for this market. The aim of this work was to verify the effects of storage temperatures and packaging on the conservation of minimally processed prickly pear. Ripe fruits with greenish exterior were used, and after peeling and sanitization were placed into one of the following storage methods: (1) Transparent polyethylene terephthalate (PET) packaging with lid; (2) Plastic coating PD 900®; (3) Polyvinyl chloride layer coating layer coating of 11 µm, or (4) 14 µm thickness. The units were stored for 12 days in refrigerated chambers at 3±1°C and 80±2.5% RH, or at 6±1°C and 70±2.5% RH. Analysis of fresh mass loss, CO2 rate, luminosity, chromaticity, soluble solid content, titratable acidity, carotenoids, and sensory analysis for appearance and color were performed every three days. The PET packaging with lid, associated with storage at 3ºC, promoted the best results for quality maintenance of minimally processed prickly pears for up to twelve days.   Key words: Carotenoids, minimal processing, Opuntia ficus indica (L.) Mill, postharvest, quality.

POSTHARVEST OF BELLFLOWER CUT FLOWERS TREATED WITH PULSING OF SUCROSE

Campanula medium, popularly known as bellflowers, belonging to the Campanulaceae family, is marketed as potted flowers or cut flowers. In cut flowers due to the senescence process it is often necessary to add sources of carbohydrates in the pulsing solution for respiration maintenance and osmotic regulation. Therefore, the aim of this study was to determine the concentration of sucrose in pulsing treatments for bellflower stems conservation. ‘White’ bellflower stem flowers were standardized with 60 cm length and 15 to 20 opened flowers and treated individually for 24 h in a pulsing solution of sucrose at concentrations of 0, 1, 3 and 5%. The stems were transferred to vases containing 200 ml of tap water and kept until the end of vase life. Daily the water uptake, fresh mass loss of stems, SPAD index of leaves and flower longevity were evaluated. The higher water absorption was observed in stems treated with 5% sucrose. There was stem mass loss 24 h after pulsing, however, at concentrations of 1 and 3% the mass of the stems were constant until the end of vase life. The flower stems treated with 1% kept the SPAD index, that measures the green color of the leaves, for longer period when compared with the other treatments. The longest vase life of 6.8 days was observed in stem flowers treated with 1.0% and lower longevity of 3.6 days was obtained from stems treated with 5% sucrose pulsing solution.

Conservação de manga com uso de fécula de mandioca preparada com extrato de cravo e canela

O objetivo deste trabalho foi avaliar a conservação pós-colheita de mangas 'Palmer' e o desenvolvimento de fungos fitopatogênicos nos frutos, após o revestimento por fécula de mandioca, preparada com águas de cravo e de canela. Para execução do trabalho, foram utilizados cinco tratamentos: T1= testemunha (sem revestimento), T2= imersão em solução de fécula a 3%, preparada com água de cravo, por 12 horas, T3= imersão em solução de fécula a 3%, preparada com água de canela, por 12 horas, T4= imersão em solução de fécula a 3%, preparada com água destilada, T5= imersão em solução de fécula a 3%, preparada com água de canela, por 24 horas e T6= imersão em solução de fécula a 3%, preparada com água de cravo, por 24 horas. Esses frutos foram armazenados em câmara a 25 ºC, por dez dias. Foram avaliados perda de matéria fresca, firmeza, cores interna e externa, pH, sólidos solúveis, ácido ascórbico, acidez titulável e identificação de patógenos presentes nas lesões. O revestimento de mangas 'Palmer' por fécula de mandioca, preparada com águas de cravo ou de canela, não influenciou na maioria das características de pós-colheita avaliadas. Entretanto, o revestimento assim preparado reduz a percentagem de fitopatógenos durante o armazenamento, sendo o extrato de cravo mais eficiente que o extrato de canela.

Differences in the mobility of Cd, Cu, Pb and Zn during composting of two types of household bio-waste collected in four seasons

The objective of this study was to evaluate the mobility of Cd, Cu, Pb and Zn during 3 different compost aeration rates of household bio-waste, originating in urban settlement (U-bio-waste) and family house buildings (F-bio-waste). The first two weeks, when the thermophilic composting phase became, the highest decline of exchangeable content was recorded. After 12weeks of composting, lower exchangeable content was found in the case of U-bio-waste composts than F-bio-waste composts, despite higher loss of fresh mass. The order of fractions in both final composts was as follows: residual>oxidizable>reducible>exchangeable. The exchangeable portion of total content in final composts decreased in this order: Zn (17%), Cd (11%), Pb (4%) and Cu (3%). Regarding the low exchangeable content of heavy metals and high-quality organic matter, these types of composts could be used not only as fertilizer, but for remediation of metals contaminated land.

Effectiveness of Ozone on Postharvest Conservation of Pear (Pyrus communis L.)

The objective of this study was to evaluate the effect of ozone (O3) treatment on postharvest quality of pear cv. ‘Williams’. Pears were exposed to gaseous ozone at the concentration of 100 ppm for 60 minutes in a flow rate of 2.3 L min-1 and stored in BOD incubators at 25 ± 2°C, 75-85 % relative humidity, for 13 days. Fruit quality was evaluated at the beginning and at days 3, 6, 9 and 13 of storage for the following variables: Fresh Mass Loss (FML), Titratable Acidity (TA), Total Soluble Solids (TSS), pH and microbiological examination (total aerobic mesophilic count and total yeast and mold count). The variables Fresh Mass Loss (FML) and Total Soluble Solids (TSS) were significantly affected by the ozone treatment. In general, the microorganism counts in ozonatedpears were lower than those in untreated pears. The treatment with gaseous ozone increased the shelf life of the pears with efficient microorganism control, did not affect the quality parameters pH and titratable acidity and delayed soluble solids increase.

Quality of Melon 'UFERSA-05 var. <i>ACIDULUS</i> and Pele de Sapo “Mabel” Minimally Processed, Kept in Different Packages

This study aimed at evaluating the quality of melon Pele de Sapo “Mabel” and Yellow melon “UFERSA-05” minimally processed preserved in different packages. The fruits were harvested at Mossoro-RN and transported to Serra Talhada-PE. In the first study, melon fruit Piel de Sapo “Mabel” was selected, washed, weighed, cooled, peeled, cut into cube shape, sanitized in chlorine solution, drained, packaged in rigid polypropylene tray, sealed with polypropylene film or polypropylene rigid cap and kept for 8 days at 8℃. In the second study, fruits of yellow melon “UFERSA-05” and Pele de Sapo “Mabel” were minimally processed and kept in rigid polypropylene tray, sealed with polypropylene film and stored for 8 days at 8℃. There was no significant interaction between packaging (sealed with film and polypropylene cover) and period of conservation, for pH, total titratable acidity (TTA), total soluble solids (TSS) and Loss of fresh mass (LFM) for Melon “Mabel”. While there was significant interaction between types of melon (“UFERSA-05” and “Mabel”) and storage period (0, 2, 4, 6, and 8 days) for pH, TTA and TSS. In sensory evaluation were noticeable changes in appearance, flavor, aroma and flesh firmness, characterized by translucency, alcoholic aroma and softening in “Mabel” melon kept in tray with lid. Melon “UFERSA-05” showed lower pH, total soluble solids, total soluble sugars, PME activity, lack of translucency high flesh firmness compared to “Mabel” melon during storage. The high levels of sugars in melon “Mabel” may be related to the incidence of translucency, which was not observed in “UFERSA-05” melon, with a strong potential to minimal processing.

Ethylene and 1-MCP affect the postharvest behavior of yellow pitahaya fruits (Selenicereus megalanthus Haw.)

The pitahaya or dragon fruit is one of the most representative exotic fruits that Colombia has, with an important, growing international market, but the cultivation and postharvest of this fruit lack sufficient technological support to be more competitive. Therefore, alternatives that provide good-quality products that meet market requirements are very important. Therefore, the objective of this research was to determine the effect of a ripening retardant and ethylene application on the conservation and quality of pitahaya fruits and the possible changes during ripening associated with ethylene, for which a completely randomized design with three treatments was used, corresponding to the application of ethylene (ethephon, 3 mL L-1), 1-methylcyclopropene (1-MCP, 600 mg L-1) and a control, with four replications, for a total of 12 experimental units. The fruits were stored at 18°C with 75% relative humidity. The 1-MCP application significantly decreased the loss of firmness, total soluble solids, loss of fresh mass and respiratory rate. Fruits from the control and ethylene treatment tended toward a climateric respiratory behavior. The total carotenoid content of the fruits was significantly higher in the ethylene application and the control treatment, which was consistent with the color change of the fruits. It can be concluded that the 1-MCP application reduced the ethylene action, slowing the ripening of the dragon fruits.

Cold storage of peaches cv. Aurora grown in the Zona da Mata Mineira, Minas Gerais State, Brazil

This study aimed to evaluate the postharvest behavior of peach cv. Aurora 1 harvested in the Zona da Mata region of Minas Gerais in two ripening stages and kept under different storage temperatures. Fruits on mid-ripe and fully ripe stages were stored at three temperatures: 5.6 ± 1.57 °C and 72.8 ± 3.8% RH; 10.4 ± 0.5 °C and 95.8 ± 5.5% RH; 21.04 ± 1.63 °C and 96.9 ± 2.6% RH up to 28 storage days (SD) . During storage, fruits stored at 21.04 ± 1.63 °C were evaluated every two days until 8 SD, and every four days for fruits stored at other temperatures. The harvest day was assigned as day zero. The variables evaluated were CO2 production, color of the pericarp and pulp, fresh mass loss, flesh firmness, total soluble solids, titratable acidity, contents of ascorbic acid and carotenoids. The fresh mass loss increased during storage, peaking at 5.6 °C. The reduction in ascorbic acid content was higher in fully ripe fruits at all temperatures. Mid-ripe fruits reached the end of the storage period with better quality. The temperature of 10.4 °C was the most efficient in keeping postharvest quality of peach cv. Aurora 1 harvested in the Zona da Mata region.

Conservação pós-colheita de pinha com uso de 1-metilciclopropeno

A aplicação de novas tecnologias torna-se necessário para aumentar o período de comercialização da pinha (Annona squamosa ) que apresenta alta perecibilidade e vida útil curta. Com o objetivo de retardar a evolução do amadurecimento, as pinhas foram tratadas com 1-metilciclopropeno (1-MCP) nas concentrações de 0; 200; 400 e 600 nL L-1, durante 8 horas, a 25ºC. Posteriormente, os frutos foram armazenados a 15ºC, durante 21 dias. Em intervalos de sete dias, amostras foram retiradas da câmara para análises quanto à firmeza, perda de massa fresca, coloração (cromaticidade e ºHue), pH, sólidos solúveis (ºbrix), acidez titulável, relação sólidos solúveis/acidez titulável, teor de amido, açúcares totais, açúcares redutores e sacarose. Não houve efeito significativo dos tratamentos quanto ao pH, sólidos solúveis, acidez titulável, relação sólidos solúveis/acidez titulável, perda de massa fresca e sacarose, somente efeito de tempo de armazenamento. A acidez titulável não apresentou modelo estatístico que explicasse o efeito da época de armazenamento. Houve interação significativa da concentração de 1-MCP e dos dias de armazenamento em relação à firmeza, coloração, teor de amido, açúcares totais e açúcares redutores. Quanto maior a dose de 1-MCP aplicado, mais lenta foi a evolução do amadurecimento, sendo que a concentração de 600 nL L-1 foi a que melhor retardou o amadurecimento .

Ácido cítrico e quitosana na conservação de lichias 'Bengal'

Este trabalho teve como objetivo avaliar a aplicação de ácido cítrico em duas concentrações, associadas ou não à quitosana, na manutenção da qualidade de lichias 'Bengal'. Após a colheita e seleção, os frutos no estádio de maturação maduro foram imersos por 1 minuto nas seguintes soluções de ácido cítrico e de quitosana: [1] Testemunha - sem imersão; [2] ácido cítrico a 300 g L-1; [3] ácido cítrico a 300 g L-1 + 0,3% quitosana; [4] ácido cítrico a 300 g L-1 + 0,6% quitosana; [5] ácido cítrico a 600 g L-1; [6] ácido cítrico a 600 g L-1 + 0,3% quitosana; [7] ácido cítrico a 600 g L-1 + 0,6% quitosana. Após a imersão, os frutos foram colocados em gôndolas para escorrer o excesso de solução. Em seguida, foram armazenados em câmara fria, previamente higienizada, a 5ºC, durante 20 dias. O experimento foi conduzido seguindo um delineamento inteiramente casualizado, num esquema fatorial composto por sete soluções de recobrimento e cinco datas de amostragem. A cada cinco dias, foi avaliada a perda de massa fresca dos frutos, a coloração, o teor de antocianinas e a atividade das enzimas polifenoloxidase e peroxidase da casca. A solução de ácido cítrico a 600 g L-1, associada ou não à quitosana, e a combinação de quitosana 0,3% com 300 g L-1 de ácido cítrico foram as mais eficientes para a manutenção da cor avermelhada e a redução do escurecimento da casca de lichias 'Bengal' por 20 dias, a 5ºC.

Quality of mini tomatoes harvested at two maturity stages and kept chilled in three packages

The economic importance of small tomato fruits has been increased considerably due to the significant levels of lycopene and sugars. However, to achieve these compounds, the harvest is limited to a ripening stage demanded by consumers, which could reduce this marked period. Harvesting at an early stage and use of conservation techniques are desirable to amplify the marketing period. The aim of this study was to evaluate the quality of small tomato fruits, Sweet Grape cultivar, harvested at two stages of ripening (light red and red), kept in three types of package (perforated PET, PEBD 30 μ and Vegetal Pack 18 μ) at a temperature of 20±1ºC and a relative humidity (RH) of 85±5% during 20 days. During this period, gas composition inside the packaging (O2, CO2 and ethylene), peel color, fresh mass loss, soluble solids content (SS), titratable acidity (TA), SS/TA and ascorbic acid levels were evaluated every 5 days. The lycopene content was determined at the beginning and the end of conservation. The experimental design was completely randomized in a split plot with four replications. Mass loss, peel color and gas composition were affected by both stage of harvest and package. The total SS/TA increased 4.74 during the conservation for two stages, regardless of package. The light red fruits reached after 20 days of conservation, mean levels of lycopene of 16.47 mg 100 g-1 and SS/TA of 18.43; on the other hand the red fruits achieved 15.30 mg 100 g-1 of lycopene and 16.80 of SS/TA. There was a mean increase of 8.4 mg 100 g-1 of lycopene in light red fruits, while in red fruits, the increase was 0.9 mg 100 g-1. The PEDB film was the best to maintain the fresh mass and peel color, therefore it was indicated for the maintenance of these attributes. The Vegetal Pack film showed no advantage in relation to the PET perforated packaging.

Physicochemical monitoring of minimally processed pineapple with the use of edible films based on maltodextrin

Minimally processed products have become more important in the marketing of fruits and vegetables due to increasing consumer demand for convenience and nutritional benefits. The successful use of this technology depends on storage and appropriate treatment. This work aims to assess the quality of a variety of pineapple produced in Santa Isabel do Ivai/PR/Brazil, noting the application of a conservative solution and different edible films in the conservation of the fruit. The minimally processed fruits were stored under cooling at 3oC for 15 days. The assays carried out were: pH, loss of fresh mass, total soluble solids, total acidity titration, ratio, total soluble sugars, reducing sugars, ascorbic acid and humidity. According to the results, the treatment (T6) that used conservative solution and edible film made of 3.0% of maltodextrin and 0.4% sunflower oil showed the best results for conservation pineapple minimally processed.

Influência do cálcio e do silício, via fertirrigação, na qualidade de hastes florais de gérbera

<p>Com o objetivo de estudar o efeito do cálcio (Ca) e do silício (Si), via fertirrigação, na qualidade de flores cortadas de</p><p>gérbera, foi conduzido um experimento em casa de vegetação, no delineamento experimental em blocos casualizados, em esquema de parcelas subdivididas, sendo os tratamentos constituídos por três níveis de Ca (7,5; 10,0 e 12,5 mmol.L-1) e quatro níveis de Si (0; 2,95; 4,43 e 5,89 mmol.L-1), aplicados via solução nutritiva, avaliados em três épocas, com três repetições. O cultivo da gérbera foi feito em vasos plásticos de 5L, preenchidos com fibra de coco. A partir do início das aplicações, na fase reprodutiva, foram avaliados a qualidade das hastes florais no ponto de colheita, pelo comprimento e diâmetro da haste, diâmetro do capítulo e intensidade da coloração das pétalas (L, C, a, b e hº), além da longevidade e perda de massa no período pós-colheita. A qualidade das hastes florais sofreu influência da aplicação de Ca e Si para o parâmetro a, cromaticidade e comprimento da haste, aos 90 e 150 dias após o transplante (DAT). O Si aplicado semanalmente via solução nutritiva durante o cultivo da gérbera aumentou a vida pós-colheita de flores coletadas aos 210 DAT.</p>

PACKAGING TO PRESERVE ''AURORA-1' PEACHES FROM TWO MATURITY STAGES

The main objective of this research was to evaluate chemical and physical changes in 'Aurora-1' peach harvested at two maturity stages, packed in different types of packaging and kept under refrigeration. Fruit were harvested at the mature green and ripe stages, packed in four different types of packaging (control, PD-900, PVC and PET) and stored at 6°C. The following variables were evaluated every eight days: coloration, accumulated fresh mass loss, firmness, appearance, acidity, total soluble solids contents, soluble sugars, and percentage of pectin solubilization. We observed that the postharvest life was influenced by packaging and the mature green fruits showed lower disease occurrence. Fresh mass loss was lower in packed fruits. The peel of mature green fruits developed a characteristic ripe peach color at the end of storage, but PD-900 provided a delay in color change. Packaging also influenced the firmness, allowing for more firmness retention than for the control fruits at both harvest stages. The organic acid content decreased in the packaged fruits and increased in the control fruits. In the packaged fruit, the amount of sugar increased until the eighth day and then decreased until the end of the storage period. The 'Aurora-1' peaches did not show compromised quality by packaging use and exhibited an increase in harvest life to 24 days (compared to 16 days for the control).

THE EFFECTS OF PIECE SIZE AND STORAGE TEMPERATURES ON MINIMALLY PROCESSED 'AURORA-1' PEACHES

The production of minimally processed fruit has increased significantly in the last few years due to the high nutritional value, convenience and safety of minimally processed fruit. The objective of the present study was to evaluate the effects of the conservation temperature and processing conditions on the quality and shelf-life of minimally processed peaches. The processing procedure consisted of washing, sanitization, peeling and stone removal. To remove the stone, the fruit was cut longitudinally, and three types of products were obtained, including halves, quarters and one-eighth segments. The fruit pieces were immersed in 2% ascorbic acid for 3 min and were packed in rigid polystyrene trays (Meiwa© M-54) coated with 14 μm PVC film (Omnifilm) (about 200 g per pack). The pieces were stored at 65% RH at 3, 6 or 9°C for 12 days, and were evaluated every four days. The appearance, fresh mass loss, color, O2 and CO2 concentration, acidity, total soluble solids, total and soluble pectin content and ascorbic acid concentration were measured. Minimally processed peaches stored at 3°C maintained higher quality due to control of ripening and senescence Moreover, an interaction effect between one-eighth segments and a temperature of 3°C was observed, and fruit with a superior appearance and higher soluble solids content was obtained.

USE OF NATURAL PRODUCTS FOR POST-HARVEST PRESERVATION OF 'VEGA' CUT ROSES

Use of natural products as floral preservatives has helped to reduce the indiscriminate use of chemical products in flower preservation. In this study, we tested the ability of certain natural products to maintain the quality and to increase the commercial durability of 'Vega' cut roses. We employed a randomized factorial design with six post-harvest treatments and four evaluation dates. The following treatments were tested: 1) distilled water; 2) methyl jasmonate (350 mu M) applied in a four-hour pulse; 3) methyl jasmonate (500 mu M) spraying; 4) mint oil (100 ppm); 5) ginger oil (100 ppm); and 6) propolis (0.05%) as a maintenance solution. Flowers were kept at 20+/-2 degrees C and 67+/-3% RH. Physiological and qualitative evaluations were conducted. Natural products had a beneficial effect on the shelf life of the flowers. However, for all evaluated parameters, the methyl jasmonate spray was the most efficient treatment to maintain floral quality, resulting in less fresh-mass loss and a lower flower respiratory rate. Methyl jasmonate spray also improved the maintenance of coloration, relative water content and concentration of reducing sugars, thus extending the shelf life of roses.

Non-invasive quality determination of spinach under simulated sale conditions and prediction of possible changes

Chlorophyll fluorescence, especially the optimum quantum yield Fv/Fm, is used to quantify the physiological state of plants, because stress, infections or wilting may lower the optimum quantum yield. The characteristics of chlorophyll fluorescence have attracted our attention for its use to determine the quality of spinach, because the measurement of Fv/ Fm during storage can be performed quickly and non-destructively, delivering information about spinach quality and its sale suitability. Applicability of modern techniques for quick and non-invasive in vivo determination of such parameters as quality and freshness of spinach under simulated sale conditions was tested in our study. In this experiment, application of chlorophyll fluorescence for quantification of quality as well as physical and physiological changes which occur in fresh products was verified. The experiment was conducted on spinach, a product characterized by rapid appearance of postharvest losses. Spinach was harvested as leafy vegetable for direct consumption and stored for 5 days (16 h in a cooling room at 2-4°C, 96-98% relative humidity, followed by 8 h at room temperature: ca 22oC, 65% relative humidity). Variants were represented by different cultivation conditions (fertilizer, leaf application of Previcur, CaCl2 and Cerone). The investigations revealed that fresh mass losses in the postharvest phase could be described by changes of Fv/Fm spinach leaves adapted to darkness by a linear relationship of parameters (r=0.77). The disadvantage of chlorophyll fluorescence measurement was the less precise determination of the critical loss of fresh mass of 3%. Instead, losses of 4 to 5% resulted in a the decrease of optimum quantum yield below the critical value of 0.80, which indicates the occurrence of postharvest stress. Leaf application

Breakdown of mangrove leaf litter in a replanted mangrove forest in Kalpitiya, Puttlam lagoon

The mangroves in Puttlam Lagoon were exploited by coastal communities for various purposes such as for fuel wood, for construction timber fencing and for shrimp farms. In order to protect and expand the mangrove vegetation the Turtle Conservation Project (TCP) has initiated a mangrove rehabilitation program in Puttlam Lagoon. By this project Rhizopora mucronata was replanted as it is the dominant species in the area. The present study was conducted with a view to assess the decomposition rate of R. mucronata leaves under replanted conditions. Decomposition of the selected sp leaves was studied in situ using litter bags in 5 years old replanted sites in Kalpitiya, Puttlam lagoon. Four sites were selected for the study as Eththala, Palakuda, Palliwasathurai and Anawasala in Kalpitiya. Litter samples were placed in 0.5 x 0.5 m litter bags and placed on the plantation floor to assess the litter decomposition rate. During 123 days decomposition experiment in each site, Eththala(83.95%), Palakuda(71.99%), Palliwasathurai(82.51%) and Anawasala (92.10 %) weight loss of fresh mass was recorded. According to the p-value (0.452) there were no significant differences in dry weight mass loss among these 5 year old replanted sites. A single exponential decay model was used to describe the rate of decomposition in each site. According to the results obtained from the exponential model rate of decomposition constant per day was 0.02, 0.01, 0.01 and 0.02 in Anawasala, Palakuda, Palliwasthurai and Eththala respectively. There was no significant difference of rate of decomposition constant in each site. The time in days required for the loss of half of the initial dry mass was 34, 67, 49 and 49 in Anawasala, Palakuda, Palliwasthurai and Eththala respectively. In order to calculate the maximum decomposition limit for litter decomposition for a period of one year, time spent in data collection data was not sufficient. Therefore, it was forecasted the limit value according to the pattern of decomposition and trend analysis with Minitab 14. The maximum decomposition values for Rhizophora mucronata replanted sites were 99.99%.

Recobrimentos comestíveis na conservação pós-colheita de 'Mexerica-do-Rio'

Objetivou-se avaliar o efeito de diferentes concentrações de fécula de mandioca na conservação pós-colheita de frutos de 'Mexerica-do-Rio' armazenados em temperatura ambiente. Os frutos, colhidos no estádio de maturação fisiológica no pomar experimental da UFV, foram selecionados, higienizados,imersos em suspensões de fécula de mandioca a 0; 2; 3 e 4% (p.v), acrescidas de 0,5 mL.L-1 de óleo mineral por 5 minutos e armazenados a 21,0 ± 1,0°C e 85 ± 5% UR, por até 12 dias, sendo avaliados a cada quatro dias. Houve perda de massa fresca em todos os tratamentos, mais drástica naquele onde não houve aplicação de biofilme, sendo que essa perda de massa refletiu à redução no teor de suco. Constatou-se redução significativa do conteúdo de vitamina C e acidez titulável, com exceção desse último quando se utilizou a maior dose de fécula.

Vida útil e qualidade de frutos de tomateiros tratados com paclobutrazol

A aplicação de reguladores de crescimento pode influenciar todas as fases do desenvolvimento de uma planta, incluindo o florescimento, o desenvolvimento e a maturação de frutos e sementes. Assim, avaliaram-se as principais características físicas e químicas e a vida útil dos frutos de tomate obtidos de plantas tratadas com paclobutrazol - PBZ (0, 50 e 100 mg L-1), via rega de mudas, aos 15 dias após a semeadura. Os frutos foram analisados imediatamente após a colheita e aos cinco, 10, 15 e 20 dias de armazenamento, em condições ambientes. A eficiência dos tratamentos e a qualidade dos frutos foram determinadas por meio da perda de matéria fresca, firmeza da polpa, teores de sólidos solúveis (SS), acidez titulável (AT), vitamina C e relação SS/AT. Adotou-se o delineamento experimental inteiramente casualizado, em esquema fatorial 3 x 5 (três concentrações de paclobutrazol x cinco períodos de armazenamento em temperatura ambiente). As aplicações de paclobutrazol em mudas de tomateiro, aos 15 dias após a semeadura, nas concentrações de 50 e 100 mg L-1, não alteraram a vida útil dos frutos do tomate longa vida AF 7631. O aumento das concentrações de PBZ resultou em menor perda de matéria fresca dos frutos e sua menor firmeza e acidez. Os teores de sólidos solúveis e de vitamina C e a relação SS/AT não se alteraram com o aumento das concentrações de PBZ. Os frutos, independentemente das concentrações de PBZ aplicadas às mudas, chegaram aos 20 dias de armazenamento (25 ± 2 ºC e 75 ± 5% UR) em condições para consumo, mesmo tendo perdido significativa quantidade de matéria fresca, acidez e firmeza.