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Peach palm has regions adjacent to the heart-of-palm that are normally neglected by the industry, and have potential to be utilized in minimally processed form. We characterized three parts of peach palm, evaluating anatomical, physicochemical and physiological parameters aiming to increase the industrial yield and evaluate shelf-life of the fresh-cut product. Harvested rods were sectioned into apical, median and basal segments, and analyzed for yield, firmness, soluble solids, titratable acidity, vitamin C, sugars and starch. Segments were sampled for anatomy and measurement of ethylene and respiration rates. After fresh-cut operations, segments were stored for 15 days at 5 °C and evaluated for surface color and carbohydrate content. The total yield based on length and fresh-mass was 85% and 70%, respectively. Hearts of palm were firmer toward the edges of apical and basal regions; the median region was the softest (14 N). The median region showed the highest SSC, 8.6 oBrix and vitamin C, 9.4 mg ascorbic acid 100 g−1 FW, and maintained the highest ethylene production, either whole or sliced. Respiration rate of all regions decreased 1 h after segmentation, the apical region showed the highest rate, 364 mL CO2 kg−1 h−1, followed by median and basal. Yellowing and pronounced color difference occurred after two weeks of storage in all the studied regions. Partially differentiated vascular bundles were present in all regions. Based on firmness and chemical parameters, all regions have potential for use as minimally processed product and can be stored up to 7 days, maintaining the original color.

Cashew apple (Anacardium occidentale L.) quality traits such as firmness, pH, total soluble sugar (SSC), soluble solid (SS), titratable acidity (TA), SS/AT ratio (flavor), vitamin C (VC), total carotenoids (TC), total flavonoids (TF), total polyphenols (TP) and total antioxidant activity (TAA) are critical factors for fruit quality assessment. We are reporting here a set of results obtained with a near infrared spectrometer using the 830–2,500 nm range, showing good prediction of the quality traits cited above in the ripe early dwarf cashew clones by partial least squares (PLS) algorithm. The intact cashew apples spectra resulted in good predictions of firmness (R2 = 0.92; RMSEP = 0.71), pH (R2 = 0.84; RMSEP = 0.17), SSC (R2 = 0.86; RMSEP = 0.99), SS (R2 = 0.90; RMSEP = 0.70), TA (R2 = 0.96; RMSEP = 0.055), flavor (R2 = 0.87; RMSEP = 7.5), VC (R2 = 0.92; RMSEP = 38), TC (R2 = 0.97; RMSEP = 0.089), TF (R2 = 0.95; RMSEP = 0.86), TP (R2 = 0.94; RMSEP = 27) and TAA (R2 = 0.93; RMSEP = 34). Near Infrared Spectroscopy (NIR) is a valid approach to study the physiology of early dwarf cashew clones, and the presented NIR methodology is expected to be an alternative for cashew germoplasm banks as a tool to support the database of images spectra for a rapid and robust phenotyping.

To control enzymatic browning in minimally processed yacon (Smallanthus sonchifolius), strategies combining anti-browning agents and modified atmosphere were investigated. Yacon slices were immersed in anti-browning agent solutions—sodium metabisulfite (0.5 %), L-cysteine (0.5 %), or the acids lactic (1 %), malic (1 %), succinic (1 %), ethylenediaminetetraacetic (EDTA; 1 %), ascorbic (3 %), citric (3 %) or tartaric (3 %), or a control (0.5 % de sugar)—for 5 min, then packaged with air or modified atmosphere (N2) and stored at 5 °C. Sensory and physical-chemical (soluble solids, phenolic content, peroxidase activity, pH, color, instrumental texture, and mass variation) analyses were performed. For a given anti-browning agent, any significant difference was not found between yacon slices stored under air or N2. However, when comparing the different anti-browning agents, only ascorbic, citric, and tartaric acids were effective enzymatic browning inhibitors without significantly changing typical sensory attributes of yacon. Among them, tartaric acid is not often reported in literature for controlling enzymatic browning in vegetal products, contrarily to the two others.

The quality of baby carrots may be associated to the standard of the raw material that in turn, may be influenced by agronomic practices. Thus, the effect of planting density and harvest age were assessed on physical and morphological characteristics, yield and end quality of intact and minimally processed carrots in the form of baby carrots. A randomized block experimental design was used with the density in the plots (4 x 20 cm and 4 x 7.5 cm) and the harvest age in the subplots (50, 57, 64, 71, 78, 85, 92, 99 and 106 days), with five replications. The experimental unit consisted of 25 plants. The assessments of diameter, length, yield, secondary phloem translocation with the cambio and total carotenoids were decisive in selecting the carrot harvest age for baby carrot manufacture. Under the 4 x 20 cm and 4 x 7.5 cm adensed conditions, harvested between 85 and 92 days, carrot roots became thinner and more orange in color (with maximum carotenoid accumulation), larger and with satisfactory yields and therefore more acceptable for minimal processing in the form of baby carrots. Thus the decision of populational density associated to harvest age will depend on the market demand, on price, quality and other variables. The use of adensed cropping with early harvests may lead to obtain carrots and respective baby carrots that are more acceptable for commercialization. A qualidade final de minicenoura pode estar associada ao padrão da matéria prima, que, por sua vez, pode ser influenciada por práticas agronômicas. Por isso, objetivou-se avaliar o efeito da densidade de plantio e da idade de colheita em características físicas, morfológicas, no rendimento e na qualidade final de cenoura inteira e minimamente processada na forma de minicenoura. O delineamento experimental utilizado foi em blocos casualizado, tendo nas parcelas as densidades (4 x 20 cm e 4 x 7,5 cm) e nas subparcelas a idade de colheita (50, 57, 64, 71, 78, 85, 92, 99 e 106 dias), com 5 repetições onde a unidade experimental foi composta por 25 plantas. As características de diâmetro, comprimento, rendimento, descolamento do floema secundário com o câmbio e carotenóides totais foram decisivos para selecionar a idade de colheita de cenoura destinada à fabricação de minicenoura. Nos dois adensamentos estudados, as raízes colhidas entre 85 e 92 dias, tornaram-se mais finas, de cor mais laranja (com máximo acúmulo de carotenóides), maiores, com rendimentos satisfatórios e, portanto, mais aceitáveis ao processamento mínimo na forma de minicenoura. Logo, a decisão de uso de densidade populacional associado à idade para se realizar a colheita, dependerá da exigência do mercado, do preço, qualidade e de outras variáveis. O uso de adensamentos de cultivo associados com colheitas antecipadas pode proporcionar a obtenção de cenoura e respectivas minicenouras mais aceitáveis para comercialização.

The red color of the pericarp of litchi fruits is lost rapidly once harvested, which results in dark fruits, usually rejected by the consumers. The loss of color is due to degradation of anthocyanins, which is related to increase on peroxidase activity. Reducing the peroxidase action may result in the maintenance of the red color, improving the fruit shelf life. This work had the goal to evaluate the influence of pH and temperature on peroxidase activity of a partial purified preparation of pericarp, from litchi cv. Brewster fruits harvested at full red-mature stage. Peroxidase was partially purified by sequential saturation with ammonium sulfate. At 60-70% ammonium sulfate saturation, the activity of peroxidase was near 158 times higher compared to the crude extract. The enzyme showed optimum activity at pH 6.5 and no activity was detected at pH 2.5 and 9.5. Pre-incubation of the enzyme extract up to 45 minutes at pH 2.5 or 9.5 caused continuous reduction on peroxidase activity, with higher degree of efficiency at pH 2.5. The maximum activity of peroxidase was at 70°C, remaining active for a period of 120 minutes at 70 and 80°C. The enzyme was inactivated completely when heated for ten minutes at 90°C or for one minute at 100°C. The data suggest that, due to high temperature for the inactivation of peroxidase, activity maybe reduced by treating the fruits with acid or alkaline solutions.

This study characterizes dehydration and white blush processes, structural alterations and synthesis of phenolic compounds (lignin and suberin), in relation to development of white blush on baby carrot surfaces. Carrots were minimally processed as baby carrots and kept on polypropylene trays with or without polyvinyl chloride (PVC) film at 5 ± 2 °C, 90 ± 5% RH. During storage, baby carrots that were not wrapped with PVC film were rehydrated 1, 1.5, 15 and 17 h after minimal processing. Fresh-cut baby carrots were evaluated for white blush index, sensory analysis (visual scores), fresh matter loss, phenylalanine ammonia-lyase (PAL) activity and structural and histochemical changes. Increases in white blush index and subjective visual scores on the carrot surface occurred in the first hours, when the material was kept on trays without PVC film and after 3 and 6 d, when stored on trays covered with PVC film. Visual assessment of white blush resulted in a more accurate assessment than instrumental evaluation because it allowed the perception of minor differences between distinct white blush levels, especially at the tips. Hydrating baby carrot surfaces for 1 and 1.5 h after processing allowed partial absorption of water by tissues and the orange color was reestablished on the surface. Fifteen hours after processing, even after rehydration, the color did not return to the original orange standard. The rapid increase in PAL activity in the secondary phloem of baby carrots, compared to that of whole carrots, suggested a physiological response as a result of abrasion. Dehydration and structural alterations of the more superficial cell layers were the main causes of white blush in baby carrots that was not related to lignin accumulation, but rather to synthesis of non-structural phenolic compounds.

Packaging plays a fundamental role on consumers' intention to purchase as it may be the first contact between the consumer and the product. The present study used the “Focus Group” methodology to obtain information on consumers' attitudes, opinions, thoughts and concepts about minimally processed products. The results showed that the participants noticed the packaging color and transparency most. Green color was the most appreciated one, while heavily decorated packaging with excessive information on the front panel was least appreciated.

`Solar Set' tomatoes (Lycopersicon esculentum Mill.) were harvested at the mature-green stage of development and treated with 50 μL·L-1 ethylene at 20 °C. Breaker-stage fruit were dropped from 40 cm onto a solid surface to induce internal bruising and held along with undropped fruit at 20 °C. At the ripe stage, pericarp, locule, and placental tissues were analyzed for soluble sugars, vitamin C, pigments, titratable acidity, soluble solids content, pericarp electrolyte leakage, extractable polygalacturonase activity, and locule tissue consistency. Bruising significantly affected chemical composition and physical properties of pericarp and locule tissues, but not placental tissue. For bruised locule tissue, carotenoids, vitamin C, and titratable acidity were 37%, 15%, and 15%, lower, respectively, than unbruised fruit. For bruised pericarp tissue, vitamin C content was 16% lower than for unbruised tissue, whereas bruising increased electrolyte leakage and extractable polygalacturonase activity by 25% and 33%, respectively. Evidence of abnormal ripening following impact bruising was confined to locule and pericarp tissues and may be related to the disruption of cell structure and altered enzyme activity.

7 páginas, 6 figuras, 1 tabla., Carrot sticks are increasingly in demand as ready-to-eat products, with a major quality problem in the development of white discoloration. Modified atmosphere packaging (MAP) and edible coating have been proposed as postharvest treatments to maintain quality and prolong shelf-life. The combined application of an edible coating containing 5 mL L−1 of chitosan under two different MAP conditions (10 kPa O2 + 10 kPa CO2 in Pack A and 2 kPa O2 + 15–25 kPa CO2 in Pack B) over 12 d at 4 °C was studied. Respiration rate, microbial and sensory qualities as well as the contents of vitamin C, carotenoids and phenolics of coated and uncoated carrot sticks were evaluated. The use of the edible coating containing chitosan preserved the overall visual quality and reduced surface whiteness during storage. Microbial populations were very low and not influenced by coating or MAP. Edible coating increased respiration rates of carrot sticks, although this was only noticeable in the package with the less permeable film (Pack B). Vitamin C and carotenoids decreased during storage particularly in coated carrot sticks. In contrast, the content of total phenolics markedly increased in coated carrot sticks stored under moderate O2 and CO2 levels, while it was controlled under low O2 and high CO2 levels. The combined application of edible coating containing chitosan and moderate O2 and CO2 levels maintained quality and enhanced phenolic content in carrot sticks., The authors are grateful to CICYT (project AGL2007-65056), CNPq, PRODETAB and FAPEMIG for financial support and Agricola Villena for providing plant material. A. Allende is holder a contract founded by CSIC (E-30-2008-0220871).

Estudou-se o efeito da temperatura de armazenamento e do processamento mínimo sobre a atividade da fenilalanina amônia-liase (PAL), peroxidase (POD) e polifenol oxidase (PPO), em folhas de couve (Brassica oleracea var. acephala) por 15 e 9 dias, nas condições de 5 ± 1oC e de 10 ± 1oC, respectivamente. O amarelecimento e a perda de turgescência foram as principais causas para a redução da qualidade visual das folhas inteiras, enquanto nas folhas minimamente processadas apresentaram também, escurecimento, que coincidiu com o aumento na atividade da POD e PPO nas duas temperaturas estudadas. A atividade da PAL em folhas minimamente processadas mantidas a 5oC mais que dobrou até o segundo dia de conservação em relação às conservadas a 10oC. O processamento mínimo influenciou a atividade da PAL, POD e PPO. Todas as enzimas avaliadas, aumentaram a atividade durante a conservação, seja no início, no caso da PAL, ou no final, para a PPO e POD, indicando que as mudanças no metabolismo fenólico desempenha um papel importante no declínio da qualidade de couve. A conservação a 5oC retardou as alterações no metabolismo fenólico, embora nessa temperatura, a atividade da PAL foi maior, em grandeza numérica, em relação às folhas armazenadas à 10oC. 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.

Tomato (Lycopersicon esculentum Mill) fruit, cv. Solar Set, were harvested at the mature-green stage and gassed with 100 mg·kg–1 of ethylene at 20 °C. At the breaker stage, fruit were held by vacuum to avoid fruit rotation and dropped from a 40 cm height on a metallic, solid, smooth surface. Following impact, fruit were stored at 20 °C and 85% to 95% relative humidity until table-ripe stage. Bruised and unbruised fruit were then placed individually inside the electronic nose-sampling vessel and the 12 conducting polymer sensors were lowered into the vessel and exposed to the volatile given off by the fruit. Data were analyzed employing multivariate discriminant analysis (MVDA), which maximizes the variance between treatments. The degree of dissimilarity was defined using the Mahalanobis distance and posterior probabilities were calculated to accurate re-classification of cases. The differences found between bruised and unbruised fruit were highly significant (P < 0.0041). The Mahalanobis distance between groupings (28.19 units) was a dramatic indicative of the differences between the two treatments. The re-classification of bruised and unbruised fruit using a single linear discriminant function was highly accurate, being 1.0 for both bruised and unbruised fruit. The electronic nose proved to be a useful tool to nondestructively identify and classify tomato fruit exposed to harmful postharvest practices such as mechanical injuries. However, there are still some factors that must be investigated, including system stability and the development of specific sensors for specific commodities.

Tomato (Lycopersicon esculentum L.) fruits, cv. Solarset, were harvested at the mature-green stage and treated with 50 μL/L ethylene at 20C. Breaker fruits (

Suspension-cultured pear fruit cells produce low levels of ethylene during growth and division in auxin containing medium. When deprived of auxin, division gradually ceases and ethylene production falls to barely discernible levels. However, notable ethylene production can now be induced by indoleacetic acid, CuCl 2 , or 1-aminocyclopropane-1-carboxylic acid. If the auxin-deprived cells are transferred to `aging9 medium that lacks auxin but contains 0.4 molar mannitol, inducible ethylene production increases several-fold reaching levels of 40 to 60 nanoliters/10 6 cells per hour. Maximum inducible ethylene productivity is attained at varying times (1-6 days) after transfer to aging medium and appears to be temporally related to cell survival, i.e. the time of subsequent cell death. It is argued that auxin depletion initiates senescence which, in turn, leads to a transient increase in inducible ethylene production and eventual death. The limitations and potentials of the suspension-cultured pear cells as a system for the study of cellular senescence are discussed.

Application of 400 ppm aminoethoxyvinylglycine (AVG) to pear trees 6 and 2 weeks before harvest resulted in marked but variable inhibition of postharvest ripening at 20°C. AVG amplified the usual nonuniformity in the initiation of ripening exhibited by freshly harvested fruit. Prolonged storage of the fruit at 0 to 2°c counteracted the inhibitory effects with resultant rapid and uniform ripening upon transfer to 20°c. However, a physiological nonuniformity as reflected by wide differences in internal C2H4 concentration persisted well beyond the time when threshold levels for the initiation of ripening had been reached by all fruit. Probable relationships between AVG effects, cold storage, and C2H4 are illustrated diagrammatically.