Author: Customer
Company: ARO

Abstract

Flowers were used as food for thousands of years, and interest in them is growing in
the western world, where there is a continuous search for culinary innovations. Edible
flowers offer special taste and color and therefore there can satisfy the desire for
innovations. Edible flowers are already found at restaurants in salad, soup or drinks as
a colorful decoration or supplement, and there is a growing interest from individuals.
Roses are one kind of the many edible flowers, till nowadays it mainly consumed in
many cultures as tea, flavors (rose water) and medicinal herbs. Those qualities plus
their variety of scents and colors, makes the rose flowers as excellent candidates for
functional food, which is consumed fresh. One of the most prominent disadvantages
of roses as a fresh food is that their petals are usually difficult to chew, as well as their
taste is usually astringent and bitter, features which are not suitable for food. Initial
work exhibited a large group of roses (24 species), characterize by a chewable texture
and not too bitter nor astringent.
The initial objective of this study was to characterize the different rose species and
examine the possibility of marketing them as functional food. Features examined for
some of the rose flowers were: shelf life, susceptibility to Botrytis cinerea, the content
of antioxidants and characteristics of taste and smell.
Rose flowers represent a new product, as edible flowers. Therefore reliable indicators
to assess shelf life do not exist. During this study, trying to find the optimal storage
conditions, various measurements of senescence were tested: visual index (according
to senescence index), relative weight loss, and ion leakage. Among the measurements
done the CO2 and Ethylene accumulation was determined during storage. The
conclusions about preferred parameter of senescence are not yet formed, because no
one parameter was found which was correlated to all the other parameters for all the
cultivars. Shelf life depends also on the resistance to pathogens. The main pathogen
attacking roses, after harvest, is Botrytis cinerea - the gray mold fungus. Infected
roses exhibited necrosis, which spread as brown stains across the entire petal. The
sensitivity of the various roses was examined, after artificial and due to natural
infection, and classified according to their sensitivity. It was found that the most
resistant species to the fungus are "San Francisco" and "Beit Lechem", followed by
the species "English Sachet", "Red Devil" and "Eterna".
Antioxidants levels are an important indicator for nutritional value and it is an
important parameter for development of a new fresh crop. In this study it was found
that the levels of hydrophilic antioxidants of the various species are several times
higher than in different fruits and vegetables (including red pepper and plum). In this
study we detected different levels of antioxidants among the various rose cultivars. By
those levels, the roses were gathered to three groups.
In order to succeed with rose marketing as an edible flower, the roses must be
palatable. Taste tests were performed based on hedonic scale. The tests were
conducted by ten tasters. Only few cultivars excelled in more than one criteria.
"Secret", and "Eterna" Were found to be the most palatable. In addition "Secret" was
highly graded in all other criteria as well.
Based on, shelf life, susceptibility to Botrytis cinerea, the content of antioxidants and
characteristics of taste and smell, the preferred cultivars were: "Eterna", "Red devil",
"San Francisco", "Rosa Damascena", "Beit Lehem," "Amadeus," "Night Time",
"Secret" "Baron Rothschild" and "Maxim". In the future there is a need to set
standards to evaluate senescence. In addition, the sensitivity to botrytis, taste and
antioxidant content should be examined during different seasons. This work paved the
way for further research, in order to market roses as innovative and healthy functional
food, to consumers all over the world.