Advisor(s)
Abstract(s)
Edible flowers are a new gourmet product; however, they are not always available all years. Thus, it is essential
to find out technologies to guarantee this product for a longer time. Flowers of four species (borage [Borago officinalis],
heartsease [Viola tricolor], kalanchoe [Kalanchoe blossfeldiana], and dandelion [Taraxacum officinale]) were subjected to freezing
(in their natural form and in ice cubes) and analyzed in terms of visual appearance, the content of flavonoids, hydrolysable
tannins, phenolics, antioxidant activity (2,2-diphenyl-1-picrylhydrazyl radical scavenging activity and reducing power),
and microbial quality after storage for 1 and 3 months. Flowers in ice cubes showed similar appearance to fresh ones during
the 3 months of storage, whereas frozen flowers were only equivalent up to 1 month with the exception of kalanchoe.
Even though flowers in ice cubes showed good appearance after 3 months of storage, they had the lowest values of bioactive
compounds and antioxidant activity. On the contrary, when frozen, the content of bioactive compounds maintained or
even increased up to 1 month of storage compared to fresh flowers, except for borage. Furthermore, in both freezing
treatments, the microorganisms’ counts decreased or maintained when compared to fresh samples, except in dandelion.
In general, both treatments may allow keeping the flowers after their flowering times.
Description
Keywords
Antioxidant activity Edible flowers Frozen Ice cubes Microbial quality Storage
Pedagogical Context
Citation
Fernandes, Luana; Casal, Susana; Pereira, José Alberto; Pereira, Ermelinda Lopes; Saraiva, Jorge A.; Ramalhosa, Elsa (2020). Freezing of edible flowers: Effect on microbial and antioxidant quality during storage. Journal of Food Science. ISSN 0022-1147. 85, p. 1151-1159