Angelo Pedro Jacomino

Amadurecimento e senescência de mamão com 1-metilciclopropeno

Papaya (Carica papaya L.) fruits are highly perishable due the fast ripening after harvest. The search for techniques that extend the shelf life and reduce the post-harvest losses is desirable. In this study, papaya Sunrise Solo fruits were harvested in two ripening stages (green and ripe) and treated with the competitive ethylene antagonist 1-methycyclopropene (1-MCP) at concentrations of 0, 30, 90 or 270 nL L-1 for 12 h at 20oC followed by storage at room temperature (20oC) during eight days. Application of 1-MCP (90 or 270 nL L-1) delayed degreening decay. Green fruits treated with 1-MCP (270 nL L-1) presented higher firmness in relation to control fruits. 1-MCP did not affect the soluble solids of fruits. The respiration rate and ethylene production were lower in fruits treated with 1-MCP (90 or 270 nL L-1) in both ripening stages. 1-MCP extended the shelf life of green fruits from four to six days and the shelf life of ripe fruits from two to four days. The 1-MCP was efficient to delay the ripening of papayas extending their shelf life

Shelf life of peaches treated with 1-methylcyclopropene

Pessegos [Prunus persica (L.) Bastch] apresentam reduzida vida util pos-colheita devido, em parte, a sua alta taxa respiratoria e amadurecimento rapido. Estes processos estao relacionados com a producao e a acao do etileno. Pessegos cv. Aurora-1 foram colhidos em dois estadios de maturacao (verde e maduro) e tratados com o antagonista competitivo do etileno 1-metilciclopropeno (1-MCP) nas concentracoes de 0, 100, 300 e 900 nL L-1, durante 12 horas a 25oC. Apos o tratamentos os frutos foram armazenados em condicoes ambientais (25oC) durante seis dias. Os frutos tratados com 1-MCP apresentaram maior firmeza de polpa e menor perda de coloracao de fundo se comparado com os frutos nao tratados. O 1-MCP reduziu o desenvolvimento de podridoes em frutos do estadio verde, mas nao em frutos maduros. O 1-MCP apresenta potencial de aplicacao comercial em pessegos, visando retardar o amadurecimento e aumentar sua vida util de prateleira.

Maturity indexes for 'Kumagai' and 'Paluma' guavas

Harvest time is one of the main factors related to guava fruit postharvest losses. It is subjectively determined by fruit size and skin color, without any consensual standardization among the growers. The use of maturity indexes enables growers to know the ideal harvest time according to each market situation. The objective of this work was to determine the maturity indexes to identify the harvest time for guava fruit cv. Kumagai and Paluma. Skin color, fruit firmness, soluble solids, titratable acidity, ratio and ascorbic acid were analyzed. The most adequate maturity indexes for Kumagai guava fruit were skin color and pulp firmness, while for Paluma guava fruit, the best indexes were skin color, pulp firmness, titratable acidity and ratio.

Estádios de maturação e qualidade pós-colheita de goiabas 'Pedro Sato'

O presente trabalho objetivou avaliar a influencia dos estadios de maturacao na qualidade pos-colheita de goiabas Pedro Sato (Psidium guajava L.). Os frutos foram colhidos em tres estadios de maturacao, segundo a cor da casca (estadio 1- verde-escura; estadio 2- verde-clara e estadio 3- verde-amarela) e armazenados a temperatura controlada de 25±1oC e 85±5% umidade relativa do ar. No momento da colheita, os tres estadios apresentaram valores distintos de cor da casca, firmeza da polpa e da relacao solidos soluveis totais/ acidez titulavel (SST/AT). O maximo periodo de conservacao foi de 6; 4 e 2 dias apos a colheita para os estadios 1; 2 e 3, respectivamente. Ao final deste periodo, os frutos colhidos no estadio 1 apresentavam-se com a cor da casca mais verde (ho > 101,55), com maior teor de acidez e menor relacao SST/AT que os demais estadios. Os frutos colhidos nos estadios 2 e 3 nao diferiram quanto as caracteristicas fisico-quimicas, ao final do periodo comercializavel, porem apresentaram diferencas significativas quanto as caracteristicas sensoriais, sendo aqueles colhidos no estadio 3 superiores aos demais estadios.

Mudanças na respiração e no coeficiente Q10 de goiaba relacionadas à temperatura

A goiaba (Psidium guajava L.) e um fruto tropical que apresenta rapido amadurecimento, o que a torna um produto muito perecivel. Temperaturas inapropriadas durante o armazenamento e comercializacao podem acelerar a perda da qualidade dos frutos. O objetivo desse trabalho foi avaliar a atividade respiratoria (AR), a producao de etileno (PE) e o coeficiente Q10 de goiabas em diferentes temperaturas de armazenamento. Goiabas do cultivar Paluma foram colhidas no estadio 1 de maturacao (casca verde escura) e armazenadas a 1, 11, 21, 31 e 41oC. A AR e a PE foram determinadas com 12, 36, 84 e 156 h de armazenamento. As taxas de AR e PE a 1 e 11oC foram as menores, atingindo valores ao redor de 0,16 e 0,43 mmol CO2 kg-1 h-1 e 0,003 e 0,019 µmol C2H4 kg-1 h-1, respectivamente. Quando as goiabas foram armazenadas a 21oC, observou-se aumento gradual em AR e PE, as quais alcancaram valores de 2,24 mmol CO2 kg-1 h-1 e 0,20 µmol C2H4 kg-1 h-1 apos 156 h de armazenamento. As maiores AR e PE foram observadas em goiabas armazenadas a 31oC. Apesar de alta AR, goiabas armazenadas a 41oC tiveram baixa PE, similarmente aquelas armazenadas a 11oC, indicando dano por alta temperatura. Na faixa de 1-11oC, o valor medio de Q10 foi de 3,0, enquanto esse valor quase duplicou na faixa de 11-21oC, atingindo 5,9. O Q10 decresceu nas faixas de 21-31oC e 31-41oC, apresentando valores de 1,5 e 0,8, respectivamente. Conhecendo-se a variacao do Q10, da taxa respiratoria e do comportamento do amadurecimento em resposta a diferentes temperaturas, as condicoes de armazenamento e comercializacao dos frutos podem ser otimizadas para reduzir as perdas na qualidade.

Aspectos fisiológicos e microbiológicos de beterrabas minimamente processadas

The aim of this work was to evaluate physiological and microbiological aspects of fresh cut beet roots. Respiratory activity and ethylene evolution were evaluated during four hours after processing and during the storage period of ten days at 5 o C. Microbiological analysis was carried out right after processing and after ten days of storage. Intact roots showed the lower respiratory activity (5 mL CO 2 kg -1 h -1 ), whereas shredded and peeled beet roots presented a respiration rate of 30 mL CO 2 kg -1 h -1 four hours after processing. Fresh cut beet roots showed a peak during the second storage day (80 mL CO 2 kg -1 h -1 ), reducing to 30 mL CO2 kg -1 h -1 at the fourth day. No ethylene evolution was detected in intact and peeled beet roots whereas in the fresh cut material it was observed in the first hours after processing, reaching 0.90 µL kg -1 h -1 . Few variations were observed during the four-hour period after processing and during the refrigerated storage. Psychotrophic bacteria and total coliforms counts were within acceptable limits, and no Salmonella or fecal coliforms were detected.

SENSORIAL CHARACTERISTICS OF "KUMAGAI" GUAVAS SUBMITTED TO PASSIVE MODIFIED ATMOSPHERE IN PLASTIC PACKAGES

Guavas cv. Kumagai fruits were packed in plastic bags and stored at 10°C and 85-90% RH during 7, 14, 21 and 28 days, followed by open exposure for 3 days at 25°C and 70-80% RH to simulate commercial handling conditions. The packaging materials used were: multilayer coextruded polyolefin film with selective permeability (PSP), low density polyethylene film (LDPE), LDPE film with mineral incorporation (LDPEm) and heat-shrinkable polyolefin film (SHR). Guavas without plastic packages were used as control samples. The concentrations of O2 and CO2 in the package headspace and the sensorial characteristics of the guavas (skin color, pulp texture, off-flavor and overall quality) were evaluated. The LDPE film presented the higher gas barrier and promoted the lowest O2 level (0.1%) and the highest CO2 concentration (19%) inside the packages. Such passive modified atmosphere induced both off-flavor and abnormal ripeness. The polyolefin heat-shrinkable film provided poor modification in the package atmosphere, so the fruits exhibited fast senescence (decay). The film incorporated with mineral provided an atmosphere of 3% O2 and 4.5% CO2 inside the packages, which kept the fruit with good sensorial characteristics for 14 days. The coextruded polyolefin film provided an atmosphere of 0.5% O2 and 4.5% CO2 that was sufficient to maintain the fruit with good sensorial characteristics for 28 days.

Inibição do amadurecimento de abacate com 1-metilciclopropeno

Avocados (Persea americana) present high respiratory rate and high ethylene production ¾ which make them very vulnerable ¾ and the ripening control of this fruit is fundamental for increasing the shelf life. Avocados Quintal were treated with 1-methylciclopropene (1-MCP) at concentrations of 0, 30, 90 and 270xa0nLxa0L-1xa0for 12 hours at 24oC followed by storage at room temperature (24oC) during nine days. Peel and pulp color, firmness, percentage of ripened fruits (firmness £8xa0Newtons), percentage of decay, respiratory rate and ethylene production were measured daily. The experimental design was a completely randomized with factorial scheme 4 x10 and four replications of four fruits. The application of 1-MCP delayed color development of peel and pulp, maintained higher firmness and reduced fruit decay. Non-treated fruits presented ripening beginning after four days at 24oC, while fruits treated with 1-MCPxa0270xa0nLxa0L-1 presented ripening after seven days. The 1-MCP (270xa0nLxa0L-1) reduced fruit respiratory rate and ethylene production. The results permit to infer that 1-MCP application in avocados is satisfactory to reduce ripening process of fruits and to lengthen their shelf life.

Alterações anatômicas e físico-químicas associadas ao armazenamento refrigerado de pêssegos 'Aurora-1' e 'Dourado-2 '

The objective of the present study was to evaluate the anatomical and physico-chemical characteristics of Aurora-1 and Dourado-2 peaches (Prunus persica (L.) Batsch) stored at different temperatures and periods. In the first experiment, fruits were stored at 0, 3 and 6oC for 14, 21, 28 and 35 days (more two days of simulated commercialization period at 25oC). In the second experiment, fruits were stored at 0 and 3oC for 7, 14, 21, 28 and 35 days (more two days at 25oC of simulated commercialization period). The experiment was a factorial with a completely randomized design with four replicates with six fruit parcels. Dourado-2 peaches after seven days of storage at 3oC or 14 days of storage at 0oC showed woolliness characterized by a sharp decrease in firmness and low juice content. The mesocarp symptoms were characterized by a separation of cell walls, pectin accumulation into the cells and intercellular spaces. Aurora-1 peaches lost firmness without compromising fruit quality; they could be conserved for up to 35 days at 0 or 3oC; even at 35 days of storage, mesocarp did not present typical alterations of woolliness. At 35 days of storage at 6oC, the fruits of both cultivars were overripe.

Conservation of 'Pedro Sato' guavas under treatment with 1-methylcyclopropene

The search for techniques thatxa0extend shelf life of guava (Psidium guajava) fruits, and reduce its postharvest losses is desirable. The objective of this work was to evaluate the effects of concentrations of competitive ethylene antagonist 1-methylcyclopropene (1-MCP) on conservation of Pedro Sato guava fruits. Treatments consisted of 0, 100, 300 or 900xa0nLxa0L-1 of 1-MCP for 3xa0hours followed by storage atxa025oC, and 10oC with 90±5%xa0RH. The application of 900xa0nLxa0L-1 1-MCP for 3xa0hours was efficient in delaying loss of skin color, and in keeping fruit firmness atxa0both storage temperatures. The 300xa0nLxa0L-1 of 1-MCP concentration was efficient in delaying skin color loss only when fruits were stored atxa010oC. The effect of 1-MCP was quite significant on the reduction of rot incidence atxa0both storage temperatures. The respiratory rate was lower in fruits treated with 300 and 900xa0nLxa0L-1 of 1-MCP during storage atxa025oC. The product was efficient in delaying the ripening of fruits, and the concentration of 900xa0nLxa0L-1 showed the best effect.