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Previous issue date: 2010-04-30 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / In the area of food dehydration, drying of vegetables has a very representative
position, it has the objective to preserve the surplus of crops and began with sun drying.
Among the vegetable is the carrot, which had its origin in Southeast Asia and in Brazil
is a vegetable cultivated enough. The principal objective of this works is to find
alternative ways for the conservation of carrot slices by osmotic dehydration with
additional drying in heart. Were initially defined the best conditions of pre-osmotic
dehydration (temperature, immersion time, type of osmotic solution) based on the
results of humidity loss, solid gain, weight reduction and efficiency ratio of predehydrated
carrots slices. The osmotic solutions used were composed by NaCl (10%)
and sucrose (50 ? Brix) named DO1 and sucrose (50 ? Brix) called DO2. Was made
experiment of pre-osmotic dehydration of carrot slices in two temperature levels, with
complementary drying in heart with air circulation at 70 ? C. Sensory analysis was
performed and the study of slices dehydration osmotically and the slices without
osmotic treatment. The best results were obtained with the solution DO1 60?C with
immersion time of 60 min. The drying of carrot slices presented period of constant rate
and decreasing rate. The osmotic pre-treatment reduced the initial humidity of carrot
slices, reducing the time to the product to reach the same humidity content. Fick's
model, considering the shrinkage, and the Page s model, adapt satisfactorily to
experimental datas, allowing the determination of effective diffusion coefficients,
consistent with the references. The results of sensory analysis of dry product, showed
greater acceptance of sliced carrots with osmotic treatment / Na ?rea de desidrata??o de alimentos, a secagem de hortali?as ocupa uma
posi??o muito representativa, tem a finalidade de preservar os excedentes das colheitas
e teve in?cio com a secagem ao sol. Dentre as hortali?as encontra-se a cenoura, que teve
sua origem no Sudoeste Asi?tico e no Brasil ? uma hortali?a bastante cultivada. Esse
trabalho teve como objetivo principal encontrar formas alternativas de conserva??o para
fatias de cenoura, atrav?s da desidrata??o osm?tica com secagem complementar em
estufa. Inicialmente foram definidas as melhores condi??es da pr?-desidrata??o
osm?tica (temperatura, tempo de imers?o, tipo de solu??o osm?tica) baseadas nos
resultados de perda de umidade, ganho de s?lidos, redu??o de peso e ?ndice de
efici?ncia das fatias de cenoura pr?-desidratadas. As solu??es osm?ticas utilizadas
foram compostas de NaCl (10%) e sacarose (50? Brix) denominada DO1, e sacarose
(50? Brix) denominada DO2. Realizaram-se os ensaios de pr?-desidrata??o osm?tica das
fatias de cenouras em dois n?veis de temperatura, com secagem complementar em estufa
com circula??o de ar a 70?C. Foi realizada an?lise sensorial e o estudo da reidrata??o
das fatias desidratadas osmoticamente e das fatias sem tratamento osm?tico. Os
melhores resultados foram obtidas com as cenouras desidratadas com a solu??o DO1 a
60?C com tempo de imers?o de 60 min. A secagem das fatias de cenoura apresentou
per?odo de taxa constante e de taxa decrescente. O pr?-tratamento osm?tico reduziu a
umidade inicial das fatias de cenoura, reduzindo o tempo para o produto atingir o
mesmo teor de umidade. O modelo de Fick, considerando o encolhimento, e o modelo
de Page, se ajustaram de forma satisfat?ria aos dados experimentais, possibilitando a
determina??o de coeficientes de difus?o efetivos, consistentes com a literatura. Os
resultados de an?lise sensorial do produto seco indicaram maior aceita??o das fatias de
cenouras com tratamento osm?tico
| Identifer | oai:union.ndltd.org:IBICT/oai:repositorio.ufrn.br:123456789/15803 |
| Date | 30 April 2010 |
| Creators | Ara?jo, Paulyanna Medeiros de |
| Contributors | CPF:41294734415, http://buscatextual.cnpq.br/buscatextual/visualizacv.do?id=K4788622A0, Damasceno, Karla Suzanne Florentino da Silva, CPF:00000000050, http://lattes.cnpq.br/0325141188932441, Duarte, M?rcia Maria Lima, CPF:11721456368, http://buscatextual.cnpq.br/buscatextual/visualizacv.do?id=K4787740D4, Souza, Domingos Fabiano de Santana, CPF:90595920500, http://lattes.cnpq.br/7400460833577257, Silva, Osvaldo Soares da, CPF:46712453453, http://lattes.cnpq.br/6441275307028933, Medeiros, Maria de F?tima Dantas de |
| Publisher | Universidade Federal do Rio Grande do Norte, Programa de P?s-Gradua??o em Engenharia Qu?mica, UFRN, BR, Pesquisa e Desenvolvimento de Tecnologias Regionais |
| Source Sets | IBICT Brazilian ETDs |
| Language | Portuguese |
| Detected Language | English |
| Type | info:eu-repo/semantics/publishedVersion, info:eu-repo/semantics/masterThesis |
| Format | application/pdf |
| Source | reponame:Repositório Institucional da UFRN, instname:Universidade Federal do Rio Grande do Norte, instacron:UFRN |
| Rights | info:eu-repo/semantics/openAccess |
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