The effect of drying methods on viscoelastic behaviour of dehydrated fruits and vegetables

Krokida, MK; Maroulis, ZB

dc.contributor.author	Krokida, MK	en
dc.contributor.author	Maroulis, ZB	en
dc.date.accessioned	2014-03-01T01:50:30Z
dc.date.available	2014-03-01T01:50:30Z
dc.date.issued	2000	en
dc.identifier.issn	0950-5423	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/26036
dc.subject	compression tests	en
dc.subject	freeze drying	en
dc.subject	osmotic drying	en
dc.subject	vacuum drying	en
dc.subject.classification	Food Science & Technology	en
dc.subject.other	WATER ACTIVITY	en
dc.title	The effect of drying methods on viscoelastic behaviour of dehydrated fruits and vegetables	en
heal.type	journalArticle	en
heal.language	English	en
heal.publicationDate	2000	en
heal.abstract	The effect of drying methods on the rheological behaviour of dehydrated apple, banana, carrot and potato was examined by uniaxial compression tests on cylindrical specimens. Samples were dehydrated using four different drying methods: osmotic, conventional, vacuum and freeze drying. After drying samples at varying final moisture, the contents were tested for compressibility using pressures ranging hom 0.02 to 8 kg kg(-1) db. A simple mathematical model was used to describe the viscoelastic behaviour of the examined materials. Four parameters with physical meaning were incorporated in the model: the maximum stress (sigma(max)), the maximum strain (epsilon(max)), the elastic parameter (E) and the viscoelastic exponent (p). It was shown that all the parameters were dependent on both the drying method and the material. Osmotic dehydration seems to increase the viscous nature of fruits and decrease their elasticity, while freeze-dried materials seem to have the most elastic structure.	en
heal.publisher	BLACKWELL SCIENCE LTD	en
heal.journalName	INTERNATIONAL JOURNAL OF FOOD SCIENCE AND TECHNOLOGY	en
dc.identifier.isi	ISI:000088697100005	en
dc.identifier.volume	35	en
dc.identifier.issue	4	en
dc.identifier.spage	391	en
dc.identifier.epage	400	en