Lucimara Rogéria Antoniolli

Shelf life of minimally processed pineapples treated with ascorbic and citric acids

Abstract The purpose of this research was to determine the shelf life of minimally processed (MP) ‘Perola’ pineapples treated with ascor -bic acid (AA) and citric acid (CA) based on physical, chemical, sensorial and microbiological attributes. Slices were dipped into drinking water (control) or combined solutions of AA:CA (%) (1.0:0.5 and 1.0:1.0) with sodium hypochlorite (NaClO 20 mg L –1 ) for 30 seconds. The samples were conditioned in polyethylene terephtalate packages and stored at 4±1 °C per 13 days. The low peroxidase activity in the slices treated with antioxidant combinations was related to low pH values observed in these samples. The treatments 1.0:0.5 and 1.0:1.0 (AA:CA, %) favored maintenance of the initial a* values and avoided the pulp browning. The ascorbic acid increased more than double on the 2 nd day in the treated slices. By the 4 th day the CO 2 values suggested a higher respiratory activity in the slices treated with anti-browning compounds. The antioxidant treatments did not produce detectable residual flavors in the MP pineapple. Regardless of microbiological safety during the 13 days of cold storage, the control slices can be kept by 6 days, afterwards the color and dehydration become strong enough to affect the appearance. On the other hand, MP ‘Perola’ pineapples treated with 1.0:0.5 (AA:CA, %) and NaClO (20 mg L

Qualidade de maçãs 'Royal gala' submetidas ao dano mecânico por impacto e aplicação de 1-metilciclopropeno em dois sistemas comerciais de armazenamento

ABSTRACT - The objective of this study was to evaluate the effects of impact injury and treatment with 1-methylcyclopropene (1-MCP) on the quality of ‘Royal Gala’ apples in cold storage (CS) and controlled atmosphere condition (CA). The treatments were impact injury (with and without impact injury) combined with 1-MCP (0 and 625nL L -1 ). The fruits were stored for four months in CS (0°C ± 1oC and 92 ± 2% RH) (experiment 1) and for eight months in CA (1.2 kPa O 2 + 2.0 kPa CO 2 , 0°C ± 0.1oC and 96 ± 2% RH) (experi-ment 2). In CS, fruits treated with 1-MCP showed higher flesh firmness, besides larger darkened area in the damaged place, at removal from storage. After CS followed by seven days at an ambient conditions, fruits treated with 1-MCP showed higher titratable acidity, skin darkening and smaller darkening depth of flesh in the place of the damage. In CA, 1-MCP application resulted, at removal from CA storage, fruits with lower levels of soluble solids content and higher skin darkening in the place of the damage, and, after seven days of shelf life, fruit showed greater depth of darkening of the pulp in the damaged place. The impact injury caused darkening of the pulp of apples ‘Royal Gala’. 1-MCP did not inhibit the effects of impact injury, but preserved fruit quality, especially in CS. Index terms: ripening, ethylene, cold storage, controlled atmosphere.

Extended cold storage of winter pears by modified atmosphere packaging.

O objetivo deste trabalho foi avaliar a eficiencia da atmosfera modificada na manutencao dos atributos de qualidade e na extensao do armazenamento refrigerado de peras ‘Rocha’ e ‘Packham’s Triumph’. Os frutos foram acondicionados em filme de polietileno de baixa densidade linear (100 µm) com aditivo BIF 1.500 6% no interior de caixas plasticas vazadas e mantidos a 0 ± 1 °C e 90 ± 5% UR por ate 180 dias. A atmosfera modificada reduziu em 14,8% a perda de massa de peras ‘Rocha’ e em 11,5% a de peras ‘Packham’s’, apos 180 dias de refrigeracao, e mostrou-se util na preservacao da coloracao verde dos frutos, retardando em 60 e 90 dias a percepcao visual do amarelecimento da casca de peras ‘Rocha e Packham’s’, respectivamente. Houve amolecimento excessivo da polpa de peras ‘Packham’s’ controle apos 150 dias a 0 °C, seguidos por 5 dias a 20 °C, o que nao limitou o armazenamento das peras de ambas as cultivares sob atmosfera modificada. A atmosfera modificada proporcionada pela embalagem de polietileno de baixa densidade linear (100 µm) com aditivo BIF 1.500 6%, proporcionou a extensao de 30 dias no periodo de armazenamento refrigerado de peras ‘Rocha’ e de 60 dias para ‘Packham’s Triumph’.

ALTERNATIVE FOR REDUCING PHYSIOLOGICAL DISORDERS IN ‘BARTLETT’ PEARS

‘Bartlett’ pears from different harvest dates were assessed regarding to cold storage potential and reduction of physiological disorder incidence. Three harvests, the first (HD1), second (HD2), and third (HD3), were carried out at weekly intervals. The pears were assessed after the harvest, with no exposition to the temperature conditioning, after 20, 40, 60, 80, 100 and 120 days at 0 ± 1 °C and 90 ± 5% RH and after three and six days at room temperature (20 ± 1 °C). Fruit from the early harvest (HD1) showed the smallest incidence of physiological disorder during both cold and room temperature storage. The disorder symptoms became apparent in HD1 fruit after 20 days at cold storage followed by three days at 20 °C, whereas HD2 and HD3 fruit showed the symptoms before being kept in a cold room. ‘Bartlett’ pears harvested at 70.75 N flesh firmness can be stored at 0 ± 1 °C for up to 40 days and preferably commercialized within three days, when they reach the firmness for eating. The extension of cold storage as well as the trade period can result in higher physiological disorder incidence and loss of sensorial quality.

Qualidade de maçãs 'Fuji Suprema' submetidas a diferentes tipos de dano mecânico

ABSTRACT- The objective of this study was to evaluate the effect of mechanical damage by impact, com-pression and cut on the quality of ‘Fuji Suprema’ apples in ambient conditions. The treatments were: control (no mechanical damage) and mechanical damage by impact, compression and cut. Different mechanical damages did not influence the flesh firmness and hue angle of the skin. Cut damage provided fruits with lower titratable acidity, nine days after damages application. Fruits submitted to damage by impact showed higher soluble solids content, 15 days after damages application. For the L color index of the flesh, cut and impact damages caused the smallest value in all evaluations, characterizing the flesh browning. However, this effect was not observed in the skin. Cut damage presented 100% of decay incidence to the nine days after mechanical damages application. In general, it can be conclude that ‘Fuji Suprema’ apples submitted to damage by impact and cut showed loss quality, because they have flesh browning incidence in the dam-age place. Moreover, cut damage reduces postharvest life of fruits, facilitating higher percentage of rots.Index terms: Malus domestica, injury, postharvest.