Fresh Point Magazine - B2B24 - Il Sole 24 Ore

in baked goods, sauces, gelatines, vinegars, fragrant
oils, liqueurs, and herbal teas and decoctions. They
can also serve as the basis for glazed products (violets
and roses) and as dishes in their own right like
acacia flowers in batter. Rose petals and borage
(Borago officinalis) and acacia (Robinia pseudoacacia)
flowers are used in baked goods as aroma
enhancers.
A safety issue
Although still rather circumscribed, the market for
these products raises issues linked to quality and
safety. First off some of these species can be poisonous
like some Ranunculacceae of the buttercup family
and lily of the valley (Convallaria majalis). It has
also been shown that chrysanthemums can cause
allergic reactions in certain people. Then too retailers
who trade only in flowers are to be avoided because
the treatments the flowers undergo make them
unsuited for human consumption. In effect, since edible
flowers require long storage life and resistance to
machine handling, they must be protected from
sources of post-harvest microbial contamination. In
effect, storability usually ranges from two to fourteen
days at 4 °C depending on type of flower. Some can
even be dried, or frozen for used as ice-cube garnish
in drinks, and others still can be freeze-dried whole.
Nutritional qualities
There are three distinct nutritional components of
flowers. First is pollen, an important source of high
biological value active ingredients like carbohydrates,
nitrogen substances, lipids, carotenoids and
flavonoids. Next is nectar, a liquid, sweetish component
containing simple sugars amino acids (especially
prolin) and proteins, salts, organic acids, phenols,
alkaloids terpenoids. The rest of the flower like petals
contains vitamins, mineral salts and other antioxidant
substances. The colour of flowers, apart from being
an index of the presence of certain substances, high
amounts of vitamin a in yellow flowers being an example,
also play a role in determining, or inducing, the
degree of consumer preference.
The flower is a plant’s essential reproductive organ
and must remain in bloom as long as possible. This is
why is it contains high amounts of antioxidants, which
slow down the senescence caused by free radicals.
Indeed, these amounts are notably high in flowers
than can be used in foods, like those of nasturtium
(Tropaeolum major), of many liliaceae (Hemerocallis
spp.), of certain roses (Rosa rugosa e Rosa davurica)
and of chrysanthemums (Chrysanthemum spp.).
Fragrance for health
Even the fragrance of flowers comes from chemical
compounds that can be good for our health and have
Photo A. Gardini.
Foto A. Gardini.
per piatti veri e propri (come i fiori di acacia pastellati). In
pasticceria i petali di rosa, i fiori di borragine (Borago
officinalis) e di acacia (Robinia pseudoacacia) sono usati
come esaltatori di aroma.
Un problema di sicurezza
Anche se ancora limitato, il mercato di questi prodotti
pone problemi di qualità e di sicurezza. Anzitutto alcune
specie possono essere tossiche, quali le ranuncolacee
e il mughetto (Convallaria majalis). Per i crisantemi, è
stata dimostrata la capacità di causare reazioni allergiche
soggettive. Inoltre, bisogna evitare di ricorrere a circuiti
di vendita strettamente floreali, a causa dei trattamenti
che i fiori subiscono, rendendoli non compatibili
con l’alimentazione umana. A questi prodotti si richiede
lunga conservabilità e resistenza ai danneggiamenti
meccanici e, quindi, devono essere protetti da contaminazioni
microbiche dopo la raccolta. Secondo il tipo di
fiore, si ha una conservabilità a 4 °C che dura da due a
quattordici giorni. Alcuni possono essere essiccati, o
anche congelati, per guarnire cubetti di ghiaccio da utilizzare
nelle bevande, altre volte si ricorre addirittura alla
liofilizzazione del fiore intero.
Le qualità nutrizionali
Dal punto di vista dell’apporto nutrizionale, nei fiori di
Fresh Point Magazine n.11 – november/novembre 2011
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