This Article Full Text (PDF) References Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Alert me to new issues of the journal Add to Saved Citations Download to citation manager Request Permissions Request Reprints Add to My Marked Citations Citing Articles Citing Articles via Google Scholar Citing Articles via Scopus Google Scholar Articles by Bunger, A. Articles by Osorio, F. Search for Related Content Social Bookmarking                         What's this?

Osmotic Dehydration and Freezing as Combined Processes on Apple Preservation

Department of Food Science and Chemical Technology, Universidad de Chile, VicuÒa Mackenna 20, Santiago, Chileabunge{at}uchile.cl

P. C. Moyano

R. E. Vega

Department of Chemical Engineering, Universidad de Santiago de Chile

P. Guerrero

Department of Food Science and Chemical Technology, Universidad de Chile, VicuÒa Mackenna 20, Santiago, Chile

F. Osorio

Department of Food Science and Technology, Universidad de Santiago de Chile

Combined processes effects of osmotic dehydration in sucrose solutions and freezing on apple cubes preservation were analysed. Two multifactorial experimental designs, in two levels, were conducted consecutively to quantify the effects of the following factors: temperature, osmotic dehydration time, concentration of the osmotic medium and freezing rate. The response variables considered were: sensory evaluation, colour, texture, water activity (aw) and reducing and total sugars. The first experimental design selected fast freezing as the best process to preserve texture and colour of the fruit. From the second experimental design, under fast freezing, were obtained the following optimal levels: 55 ºBx for the concentration of the osmotic medium, 35 ºC for the syrup temperature and 60 min for the osmotic dehydration time. A test of acceptability was performed under these conditions with 80 potential consumers on a 7-point hedonic scale, which gave 93% acceptance. Glass transition temperature (Tg') of the maximally cryoconcentrated liquid was –41.89 ºC for the product processed under optimum conditions. Significant correlations (P= 0.05) were found between sensory and instrumental responses.

Key Words: apples • sensory evaluation • osmotic dehydration • freezing • cryostabilisation

Food Science and Technology International, Vol. 10, No. 3, 163-170 (2004)
DOI: 10.1177/1082013204044828


CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    Technorati    Twitter    What's this?