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Peach palm tree products, including palm hearts, are in high demand worldwide, often consumed either in natura or with minimal processing, and possess significant economic value in various markets. Minimally processed peach palm (Bactris gasipaes Kunth) are suitable to yellowing during storage thereby compromising its market value. In order to understand the surface yellowing in different sections of palm heart (median and basal regions), packaged or un-packaged with PVC were evaluated for anatomical and metabolic changes during 0, 4, 8, and 12 days of cold storage. The tissues showed surface yellowing at the end of cold storage. The outer cell layers exhibited differentiating parenchymal and dermal tissues, and superficial cells collapsed in the yellowing tissues. The metabolite analysis indicated reduction in the contents of some tricarboxylic acid cycle intermediates, sugars, and antioxidants in minimally processed palm heart during cold storage. The reduction in these compounds boosted the biosynthesis of amino acids in the peach palm. The highest metabolic changes and yellowing were observed after 8 days of storage, with higher intensity at 12 days, suggesting loss of quality, nutritional value, and shelf-life. Changes in the metabolites were mostly affected by storage time, and packaging with PVC provides better conditions for maintaining post-harvest quality. This pioneering study on the metabolism and anatomy of minimally processed peach palm heart fills some gaps about the yellowing, quality, and shelf life of this product.

We studied the effects of storage temperature on the activities of phenylalanine ammonia-lyase (PAL), peroxidase (POD) and polyphenol oxidase (PPO) in minimally processed kale (Brassica oleracea var. acephala) that was stored for 15 and 9 days at 5 ± 1ºC and 10 ± 1ºC, respectively. The main visual evidence for quality loss in whole leaves was yellowing and loss of turgescence. Minimally processed leaves presented significant browning, indicating increased POD and PPO activities. The PAL activity in minimally processed leaves stored at 5ºC was fourfold higher than that of whole leaves after two days of storage. We showed that minimal processing influenced PAL, POD and PPO activities. The activity of all enzymes studied increased during storage, indicating that changes in phenolic metabolism play an important role in the decline of kale quality. PAL activity increased rapidly at the beginning of storage and exhibited a reduced rate of increase over time, while the PPO and POD activities increased continuously over time. The storage at 5 ° C was a great ally in delaying changes in phenolic metabolism; however, the absolute PAL activity was higher at 5 than at 10ºC.

The aim of this study was to evaluate the effects of fresh-cut in stick form of two cassava cultivars on their biochemical and antioxidant characteristics, at two harvest times. The fresh cut cassava sticks were packaged in polypropylene, maintained at 5±1ºC, with 90±5% relative humidity for 12 days. The concentration of carotenoids, total soluble phenolic compounds and the activity of phenylalanine ammonia lyase and antioxidant capacity were significantly higher for the sticks of cultivar 'Amarela' cassava than for the sticks of cultivar 'Cacau'. The concentrations of carotenoids, total soluble phenolic compounds, and the activity of phenylalanine ammonia lyase and antioxidant capacity were all significantly greater when harvested at 14-month of age. There was a significant increase in the activity of phenylalanine ammonia lyase during the 12 days of storage at 5ºC. However, there was a decrease in total carotenoids, soluble phenolic compounds, and in the antioxidant capacity of the two cultivars.

Browning discoloration after cutting is detrimental for the quality of a number of fruits and vegetables, such as banana, apple, pear, potato, and some roots such as cassava, yam, and others. Browning and softening compromise banana after cut shelf-life in a few hours under cold storage. Therefore, anti-browning compounds have been applied to slices before packing. Some commonly used substances are calcium chloride, ascorbic acid, cysteine and citric acid, in immersed inchemical mixtures. Recent studies have demonstrated the possibility of preserving fresh-cut banana immersed in sweetened fruit juice for relatively longer periods, favoring commercialization. This type of conservation, although widely used in Brazil for fruit salads, consists of a more complex system in a physiological basis, requiring adjustment of the solution parameters, such as sugar concentration, pH and acidity, considering the viability and freshness of the plant tissue. In this short review, we discuss some experimental data and present a new method for preserving fresh-cut banana. Reduction of enzymatic activity, either in temporary dipping treatment or permanent immersion of banana slices is regarded as a key factor for maintaining its quality during cold storage.

After harvesting litchi, the red color of the fruit pericarp is rapidly lost resulting in discoloration and browning during storage and marketing. The loss of the red color is caused by the degradation or loss of stability of anthocyanins. The action of peroxidase and polyphenoloxidase is usually related to the browning and discoloration of fruits of various species. This study aimed to evaluate the influence of pH and temperature on peroxidase and polyphenoloxidase activities, in a partially purified preparation of pericarp of the litchi cultivar Bengal. Fruits were harvested at the ripe stage and polyphenoloxidase was partially purified by sequential saturation in 80% ammonium sulfate. At concentrations of 40-50% and 60-70% ammonium sulfate the activities of polyphenoloxidase and peroxidase were, respectively, 124 times and 158 times higher than in the crude extract. The activity of peroxidase and polyphenoloxidase was maximum at pH 6.5 and 7.0, respectively, and no activity was detected at pH 2.5 and 9.5. Pre-incubation of the enzyme extract for 45 min at pH 2.5 or 9.5 completely inactivated the enzymes, with the highest degree of efficiency at pH 2.5. Peroxidase activity was highest at 70ºC and remained active for a period of 120 min at 70 and 80ºC. Peroxidase became completely inactive when maintained at 90ºC for 10 min or 1 min at 100ºC. Polyphenoloxidase activity was highest at 20ºC and remained active for a period of 120 min at 40 and 50ºC and was inactivated after 10 min at 60ºC. Due to the high temperature of inactivation of the peroxidase and polyphenoloxidase activities, the enzymes can be inactivated more easily in fruits using acid or alkaline solutions.Após a colheita do fruto, a cor vermelha do pericarpo da lichia é rapidamente perdida, o que resulta em descoloração e escurecimento durante o armazenamento e comercialização. A perda da cor vermelha é devido à degradação de antocianinas ou à perda de sua estabilidade. Usualmente, a ação da peroxidase e polifenoloxidase está relacionada ao escurecimento e à descoloração de várias frutas. Avaliou-se a influência do pH e da temperatura na atividade da peroxidase e polifenoloxidase em uma preparação purificada parcial de pericarpo de cultivar Bengal. Os frutos foram colhidos no estádio vermelho maduro. A polifenoloxidase foi parcialmente purificada por saturação seqüencial até 80% de sulfato de amônio. Na concentração de 40-50% e de 60-70% de sulfato de amônio, a atividade da polifenoloxidase e peroxidase foi 124 e 158 vezes maior vezes maior do que a encontrada no extrato cru. A peroxidase e polifenoloxidase apresentaram ótima atividade em pH 6,5 e 7,0 e nenhuma atividade foi detectada a pH 2,5 e 9,5. A pré-incubação do extrato das enzimas até 45 min a pH 2,5 ou 9,5 inativou completamente as enzimas, sendo que o maior grau de eficiência ocorreu em pH 2,5. A peroxidase apresentou maior atividade a 70ºC, permanecendo ativa durante um período de 120 min a 70 e 80ºC. A peroxidase tornou-se completamente inativa, quando aquecida durante 10 min a 90ºC ou durante 1 min a 100ºC. A polifenoloxidase apresentou maior atividade a 20ºC, permanecendo ativa durante um período de 120 min a 40 e 50ºC e inativada aos 10 min a 60ºC. Devido à alta temperatura para inativação, a atividade da peroxidase e polifenoloxidase pode ser reduzida, imergindo os frutos em soluções ácidas ou alcalinas.

Atualmente, a maior parte da produção brasileira de banana é destinada ao mercado interno e, geralmente, é colhida, manuseada e transportada de forma deficiente e inadequada, contribuindo para perdas substanciais na fase pós-colheita. Objetivou-se identificar os tipos e a intensidade de danos mecânicos após a colheita da banana 'Prata-Anã', produzida no Município de Verdelândia (MG) e embalada em caixas de papelão, madeira e plástico. Foram amostradas quatro caixas de banana 'Prata-Anã' em cada etapa da cadeia de comercialização, a saber: antes da colheita, após a primeira lavagem e pré-seleção (1ª piscina da casa de embalagem), após embalagem, após transporte e após distribuição ao mercado varejista em Montes Claros (MG), onde os frutos permaneceram em exposição para vendas por 8 horas. A porcentagem de frutos, área da casca e porcentagem da área da casca danificados aumentou ao longo da cadeia de comercialização. O uso da caixa de papelão proporcionou redução na incidência e intensidade de dano mecânico em relação aos demais tipos de embalagem. Houve alta incidência do dano por abrasão em todas as etapas da cadeia de comercialização. O dano por compressão apresentou grande importância relativa no varejo.Currently, most of the Brazilian production of banana is destined for domestic market and, generally, it is harvested, handled and carried in a deficient and inadequate form, contributing to substantial post harvest losses. This work had the objective of identifying the types and the intensity of mechanical damages after the harvest of 'Prata Anã' banana grown in Verdelândia, MG and put in cardboard, wood and plastic boxes. So, four boxes of banana were evaluated in each stage of the commercialization chain: before harvest, after the first washing and pre-selection (1st swimming pool of the packing house), after packing, after transport and distribution to the retail market in Montes Claros, MG, where the fruits remained in exposition for sale during 8 hours. The percentage of fruits, skin area and percentage of the damaged skin area increased along of the commercialization chain. The use of the cardboard box provided reduction in the incidence and intensity of mechanical damage in relation to the other types of packing. There was high incidence of the damage caused by abrasion in all the stages of the commercialization chain. The damage by compression presented great relative importance in the retail.

A queda natural de frutos maduros da bananeira, resultado da separação individual de frutos da coroa da penca, também chamada despencamento, é uma característica indesejável, que pode limitar o lançamento de uma nova cultivar. O fruto destacado da penca tem vida de prateleira reduzida, além de não demonstrar boa aparência aos olhos do consumidor. Os objetivos do presente trabalho foram quantificar a suscetibilidade à queda natural dos frutos de bananeiras de grupos genômicos e ploidias diferentes, e identificar correlações entre a queda natural e diversas características físicas dos frutos. Foram utilizados 37 genótipos de bananeiras. De acordo com análise de variância e teste de Scott-Knott, os resultados evidenciaram a alta resistência ao despencamento dos genótipos pertencentes ao grupo genômico BB (Butuhan, Piraí e BB França), Terra (AAB), Poteau Nain (tipo figo) (ABB) e Thap Maeo (AAB), enquanto Prata-Anã (AAB), Grande Naine (AAA), Ambrósia (AAAA), Ouro (AA) e FHIA 18 (AAAB) obtiveram valores intermediários de resistência ao despencamento. Com relação às bananeiras suscetíveis, destacam-se os híbridos melhorados Pioneira (AAAB), YB42-21 (AAAB), Buccaneer (AAAA) e Calypso (AAAA) e a cultivar Ouro da Mata (AAAB). Verificou-se associação de 74% entre a firmeza do fruto e a resistência ao despencamento. Os estudos de grupos genômicos e ploidias indicaram maior resistência ao despencamento das bananeiras pertencentes ao grupo BB e dos genótipos triplóides ABB e AAB.Natural fruit dropping of ripe bananas in result of individual separation of fruits from the hand crown, is called finger drop, this characteristic is undesirable and would limit the marketing of new cultivars. Fruits that stand out in the hand have a reduced shelf life, and do not present a pleasant appearance for customers. This study was carried out in order to quantify the susceptibility to natural fruit dropping in fruits from different genomic groups and ploidies, and to identify correlations between natural dropping and various physical fruit characteristics. Diploid, triploid e tetraploid banana plants from several genomic groups were used, altogether 37 genotypes. The physical characteristics were used in a variance analysis and the results compared with the Scott-Knott test. Results proved the high resistance against dropping among genotypes that belong to the genomic group BB (Butuhan, Piraí and BB França), Terra (AAB), Poteau Nain (fig type) (ABB) and Thap Maeo (AAB), while Prata-Anã (AAB), Grande Naine (AAA), Ambrósia (AAAA), Ouro (AA) and FHIA 18 (AAAB) presented intermediate values of dropping resistance. Among banana plants with low resistence, the improved hybrids Pioneira (AAAB), YB42-21 (AAAB), Buccaneer (AAAA) and Calypso (AAAA) and the cultivar Ouro da Mata (AAAB) were outstanding. A higher positive correlation between fruit firmness and resistance toward finger drop could be verified. The study of genotype and ploid groups indicated a greater resistance against dropping among banana plants belonging to the BB group and ABB and AAB triploid genotypes.

Foram determinados o acúmulo de matérias fresca e seca e dos nutrientes N, P, K, Ca, Mg, Zn, Fe e Mn em bananas 'Mysore', desde a antese floral da primeira penca feminina até o completo amadurecimento. O desenvolvimento dos frutos foi lento até o 42º dia após a antese, acelerando-se posteriormente. A fase de acúmulo máximo de minerais coincidiu com a de acúmulo máximo de matéria fresca, ou seja, 112 dias após a antese. A ordem de exportação de macronutrientes pelos frutos, em seu estádio de máximo acúmulo de matéria fresca, expressa em kg t-1 de fruto fresco, foi 3,61 para K; 0,98 para N; 0,27 para Mg; 0,19 para P e 0,12 para Ca. Quanto aos micronutrientes, a ordem de exportação, expressa em g t-1 de fruto fresco, foi 7,92 para Mn; 5,99 para Fe e 2,92 para Zn. Em frutos plenamente desenvolvidos, à exceção de Ca, Mn e Zn, todos os nutrientes acumularam-se mais na polpa do que na casca.It was determined fresh matter and the nutrients N, P, K, Ca, Mg, Zn, Fe and Mn accumulation in banana 'Mysore' fruits, from female cluster anthesis to ripening. The fruit mass increment was slower until 42nd day post-anthesis and became faster later. The maximum nutrient accumulation period coincided with that of the maximum fresh matter accumulation, that happened 112 days post-anthesis. The macronutrients exportation by fruits in the stage of fresh matter maximum accumulation, expressed in kg.t-1 of fresh fruit, was 3.61 to K, 0.98 to N, 0.27 to Mg, 0.19 to P, 0.12 to Ca. The micronutrients exportation, expressed in g.t-1 of fresh fruit, was 7.92 to Mn, 5.99 to Fe and 2.92 to Zn. In completely developed fruits, excepting for Ca, Mn and Zn, all nutrients accumulated more in the pulp than in the peel.

Banana sold in the internal Brazilian market has low quality due to the presence of bruises spots spread all over the skin. In this work, the purpose was to evaluate the mechanical injury intensity in Prata Anã bananas as related to packaging type, at harvesting and during postharvest handling steps. Fruits were harvested at green unripe stage from a commercial plantation in Janaúba-MG, in July and in November 2003, and were transported to Viçosa-MG, about 800 km far way, packed in wood crates ‘torito’ + cardboard, ‘plastic’ and ‘cardboard’ boxes. Regardless the season of harvest, at least 93% of the fruits showed some kind mechanical wounding on the skin after shipping. But, the total surface skin area damaged was significantly higher during the month of November (spring) compared to July (winter) for all three different boxes. Bananas shipped inside cardboard boxes had larger wounding areas compared to ‘torito’ + cardboard and plastic boxes. Among the postharvest handling steps, which included, harvest, transport by aerial cable, preparation of finger and shipping, the last was most damaging to the fruit surface. However, the extent of wounding imposed to the fruits after had been shipped, did affect the course of ripening.