Orientador(es)
Resumo(s)
The objective of this work was to study the e ect of osmotic drying, using di erent hypertonic
solutions (sucrose and sodium chloride), on physicochemical characteristics of pansies (Viola Ö wit-
trockiana). The same treatments were applied to lettuce to compare the behavior of
owers with
other vegetables. Pansies' superhydrophobic surface structure, called papillae, increased the resistance
to exchanges with hypertonic solutions. No weight loss was observed after most treatments (sucrose:
between 2.2 and 6.8 %; NaCl: between -23.0 % and 1.5 %), aw maintained high values (> 0,94) and
monomeric anthocyanins were preserved (fresh 0.10 and 0.19 mg Cy-3glu/g fresh matter for 20%/1 h
in NaCl and 60%/1 h in sucrose). When applying more drastic conditions, as sodium chloride for more
than 1 hour, undesirable textural and color changes were observed. For lettuce, all treatments caused
osmotic dehydration, weight loss (ranged between -9.3 to -30.3 % for 80%/1 h in sucrose and 15%/1 h
in NaCl) and a reduction in aw (< 0,97) and carotenoids, with sodium chloride causing more damage
in visual appearance than sucrose. Therefore, immersion in osmotic solutions can be applied to lettuce
but the desired e ect was not achieved for pansies due to the morphological structure of the
owers'
epidermis.
Descrição
Palavras-chave
Carotenoids Lettuce Monomeric anthocyanins Osmotic dehydration Viola×wittrockiana
Contexto Educativo
Citação
Fernandes, Luana; Casal, Susana; Magalhaes, Agostinho; Baptista, Paula; Pereira, José A.; Saraiva, Jorge A.; Ramalhosa, Elsa (2019). Effect of osmotic drying on physicochemical properties of pansies (Viola × wittrockiana). International Journal of Food Studies. ISSN 2182-1054. 8, p. 23-33