This work evaluated the production of dehydrated mangoes (Mangifera indica L.) and the effectiveness of ultrasonic-assisted osmotic dehydration on the drying kinetics of mangoes. Cube shaped mango samples were pretreated using ultrasound-assisted osmotic dehydration (UAOD) and dried in a circulating drying oven. An experimental design was created to evaluate the effect of pretreatment time and osmotic solution concentration on the water loss and sugar gain in the osmotic dehydration and on the drying time. The ultrasonic pretreatment was carried out in a bath ultrasound operating at 25 kHz and outputting 55 W/m 3 of power. Osmotic solution ranging from 0 to 500 kg sucrose/m 3 was applied in the treatments, and air drying was carried out at 60°C. A mathematical model was developed for the osmotic pretreatment, and Fick's law was used to model the air-drying process. The mass transfer coefficients were estimated for the ultrasonicassisted osmotic dehydration, and the apparent water diffusivity was estimated for the air-drying process. The mass transfer coefficient ranged from 0.017 to 0.109 m 2 /s and the resistance to mass transfer at the surface ranged from 0.26 9 10 -6 to 1.22 9 10 -6 m 2 /s on the UAOD, while the apparent water diffusivity during air drying ranged from 5.94 9 10 -9 to 8.41 9 10 -9 m 2 /s. Mangoes presented a different behavior when compared to other fruits. The ultrasonic pretreatment was effective only when associated with an osmotic solution at 500 kg sucrose/m 3 .

Resumo Nos últimos anos, agricultores da região Nordeste vêm cultivando o coqueiro, visando à comercialização da água do fruto verde. Na literatura ainda são poucos os relatos Palavras-chave:Cocus nucifera L., caracterização, qualidade, volume de água. IntroduçãoO coqueiro é uma planta monocotiledônea, pertencente à família Palmae. É constituído de uma só espécie (Cocus nucifera L.). O fruto do coqueiro é botanicamente, uma drupa, sendo formado por uma epiderme lisa ou epicarpo, que envolve o mesocarpo espesso e fibroso, ficando mais para o interior uma camada muito dura, o endocarpo (PASSOS, 1998). É uma palmeira tipicamente tropical, classificada como uma das oleaginosas mais importantes do mundo. Dentre os

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High intensity pulsed UV Light is a non-thermal treatment used in sanitization of fruits and vegetables. In this work, we have applied high intensity pulsed UV light as a pretreatment for convective air-drying evaluating the benefits of the pretreatment to the drying process and to the nutritional quality of the dried product. Mangoes were subjected to pulses of UV light. The pretreated samples were further dried in a convective oven-drier until 90% of the initial water content has been removed. Drying kinetics, water apparent diffusivity, vitamin B, vitamin C content and total carotenoids content were analyzed. Pulsed UV light showed to be an interesting pretreatment for mangoes given the higher nutritional content of the dried product. Keywords: mango; drying; ultraviolet; vitamins; kinetics