A survey of wild plant species for food use in Sicily (Italy) – results of a 3-year study in four Regional Parks

A total of 658 men (82 %) and 144 women (18 %) were interviewed. The informants were aged between 60 and 90, giving and the average informant age was 73.9 years. The informants aged 70-80 years were able to supply the greatest information on the plants in terms of numbers of plants cited; less information was obtained by the younger and older age brackets. Regarding the lack of information provided by the older informants, this was in large part due to communication difficulties which arose during interviews. A far greater number of men than women were interviewed in the 4 Sicilian Parks and, therefore, the female contribution to the acquisition of information was low. This male prevalence was not intentional and was mainly due to the fact that the elderly men were more available/willing to participate. The significant lack of women in the survey we did not consider to be of decisive importance regarding information on the number of wild food plants as the men had spent most of their lives in the countryside and forests and had expert knowledge of the plants. The under-representation of women, however, may have contributed to a smaller amount of detailed information on the processing and cooking methods of wild food plants. Confirmation of this may come from Hardy’s theory [61] which maintains that the dissemination of traditional knowledge is prevalently female. All the informants said they had been resident in the area of study since birth. 72 % of informants were either retired or working farmers, foresters or herdsmen and 28 % were craftsmen, shopkeepers, teachers and housewives.

A total of 119 wild shrub and herbaceous plant species were reported as being used for food purposes (Appendix). The species belong to 34 families. For each of the species the scientific name, voucher specimen code and folk names are listed. Ethno-biological information is provided by the plant parts used, preparation methods, the food/medicinal use of species, the number of citations, the presence of the species in the Sicilian Parks and the level of perceived usefulness. Similarities in the use of wild food species between the investigated area and those reported in studies in Sicily, in other Italian regions and some Mediterranean countries are also shown. The most represented families are Asteraceae (33 species), Brassicaceae (14 species), Lamiaceae (10 species), Asparagaceae (8 species) and Leguminosae (6 species). Only 4 species with food properties from the study were identified as being endemic to Sicily, according to [51]: Asperula rupestris Tineo, Brassica rupestris Raf., Carlina sicula Ten. and Urtica rupestris Guss. The predominance of Asteraceae in food use and food/medicinal use confirmed results from a number of studies carried out in Mediterranean countries [7, 11, 14] and [62‐70]. In most cases, the species had similar names in dialect throughout the 90 towns included in the area of study. The informants used 187 dialectal names to indicate the 119 species in the study. The majority of the species were collected in the wild, or more rarely, gathered from the wild and then planted in kitchen gardens. Natural habitats such as roadsides, rocky slopes, dry meadows and uncultivated areas were the favourite habitats for gathering wild food species. Although cultivating the plants in kitchen gardens would potentially ensure their availability throughout the year, informants still preferred to gather the plants from the wild. Some aromatic species some, such as Mentha spp., are collected from natural habitats (wetlands, wet meadows), while others, such as Rosmarinus officinalis L. are often cultivated for food and/or medicinal purposes (Table 1).

The Cultural Importance Index of the 119 species in the study varied between 0.004 and 0.50 (average value: 0.08) (Appendix).

With regards to the wild food plant species used in each of the Sicilian Regional Parks, the analysis shows that Cichorium intybus L. (C.I. 0.37), Foeniculum vulgare Miller (C.I. 0.31), Borago officinalis L. (C.I. 0.23) and Asparagus acutifolius L. (C.I. 0.21) are the most important species to the local populations in terms of food use (Table 2).

The results clearly demonstrate that the most frequently-cited species were also those most commonly-used for food purposes by the local people of the Parks involved.

Cichorium intybus was most cited by the people interviewed. The aerial parts and leaves of the species are eaten boiled and the broth is consumed as a drink. The boiled parts are used to prepare salads and soups in other regions of Italy such as Latium [71], Tuscany [72] and Sardinia [73]. In Sicily, the aerial parts of common chicory are also sautéed with eggs and seasoned with olive oil [14]. In the Madonie and Nebrodi Regional Parks in particular, it is widely used for pasta sauces. The aerial parts of Foeniculum vulgare are eaten boiled, seasoned with olive oil and lemon or consumed raw in salad. This food use is also confirmed by various regions in Italy [8, 12, 74] and in several countries in the Mediterranean as reported by [14]. The aerial parts of the species are also an ingredient in a number of traditional Sicilian pasta or meat dishes and soups. The aerial parts of Borago officinalis are eaten boiled and seasoned with olive oil and lemon, or fried in batter by local populations in the 4 Sicilian Parks. The boiled water, seasoned with olive oil, has diuretic and laxative properties, as reported in most of the literature from Italian regions and other Mediterranean countries [75‐81]. The young turions of Asparagus acutifolius are eaten boiled and the boiled water consumed seasoned with olive oil. The turions may be fried with onions in omelettes, a dish particularly widespread in the Nebrodi and Monti Sicani Regional Parks but also common throughout Italy. The aerial parts of Sonchus oleraceus (L.) L. are eaten boiled and pan fried in omelettes. Lentini and Venza [14] reported that the young leaves are consumed in salads and soups in various Mediterranean counties such as Crete, Cyprus, Egypt, Spain and Tunisia. Of the more commonly cited species for each of the 4 Sicilian Parks, Laurus nobilis L. (C.I. 0.09) was found to have the lowest Cultural Importance Index. Most of the species had a very low Cultural Importance Index, this would seem to demonstrate that little cultural importance is given to these species as a food. This may be an indication of a fall in TPK (traditional plant knowledge) regarding food uses of plants. However, it would be a mistake to consider those species with a low C.I. index as uninteresting from a culinary point of view in that we would need to take other factors into consideration, such as the lesser or greater availability of the species in the natural habitat, or the greater or lesser use of the plants to cure the most widespread disorders in that same area. When considering the 90 towns in the study area individually, the cultural importance of these species was found to differ between towns, and this highlights the fact that, in quantitative analysis terms, the species is used by the local populations to differing degrees. In this study a total of 119 wild plant species were collected, 109 of which were found to be used for food purposes also in other Italian regions and 75 in the Mediterranean countries taken into consideration. Most previous studies, however, were carried out using different methodologies or in areas which differed in terms of size and floral diversity. When a comparison was made of the wild plant species in this study and those previously cited by Lentini and Venza [14] in Sicily, 65 were found to have been previously cited, whereas 54 appear to be newly mentioned. This is undoubtedly an important result for our study. When comparing the four Regional Parks, only 15 wild plant species were common to all of the parks. Most of the wild food plants were found in the Etna (65) and Nebrodi (62) Regional Parks whilst the fewest in the Sicani Regional Park (39). In general, our research indicates that 6 wild plant species have not been mentioned before in the Mediterranean area for culinary use. With reference to the culinary uses of wild plants, it was found that most of the culinary uses recorded were the same or similar to those in other parts of Sicily, as reported by [14], in other regions of Italy and some Mediterranean countries: Apium nodiflorum (L.) Lag., for example, is eaten in Sicily, Tuscany, Spain and Tunisia. It is worth noting that some culinary uses are typically found in only one Sicilian Park or another, and this would seem to be proof of a slight variation in diet between populations of the same region. The greatest range of culinary uses was found in the Etna (28) and Nebrodi Regional Parks (27). Regarding current use of the species cited in the study, 28.57 % of the species are still used today whilst the remaining part can be considered to have fallen out of use. Concerning the perceived degree of usefulness of the species for food purposes, and referring only to those species currently used by the local populations, Concerning the perceived degree of usefulness of the species for food purposes, and referring to those species currently used by the local populations, 59.66 % of the culinary uses were highly appreciated by the informants whilst only 54.62 % of the culinary uses were little appreciated. Some wild plants were recorded by the informants as being both highly and little appreciated.

The aerial parts of the plants are the parts most widely used, followed by leaves, flowers and shoots (Fig. 2); international literature also reports that the aerial parts and leaves are the most commonly used parts for culinary purpose, [14, 80, 81]. Greater accessibility in natural ecosystems of the aboveground parts of the plants and the greater abundance of the leaves compared to other plant parts may explain the higher use-frequency of these plants parts. In most cases, the various parts were used indifferently for the same culinary use only. For example, the leaves and the young shoots of Silene vulgaris (Moench) Garcke were used in quite the same way: eaten raw in salads or cooked in omelettes, and the aerials parts and flowers of Asphodeline lutea (L.) Rchb. were eaten indifferently, boiled and then fried with eggs. Further on the topic of preparation methods, the wild food species are consumed in a number of different ways: some are cooked whilst others are eaten raw and require only washing. The methods of consumptions are reported in Fig. 3. Most wild plant species are consumed boiled and nearly all (98.7 %) are eaten simply boiled and on their own. The most cited wild plant species eaten boiled are Foeniculum vulgare, Borago officinalis and Asparagus acutifolius. Some wild plant species are consumed fried, especially in the preparation of omelettes. In the Monti Sicani Regional Park, the aerial parts of Diplotaxis erucoides (L.) Dc. are typically fried with eggs and lemon in omelettes, and in the Nebrodi Regional Park the bulbs of Leopoldia comosa (L.) Parl. are sautéed with eggs to prepare traditional dishes as confirmed by [14]. A high number of plant species are consumed raw, most in salads. The aerial parts of Portulaca oleracea L., the young shoots of Clematis vitalba L., the leaves of Nasturtium officinale R. Br. are usually served with a little olive oil, salt and vinegar. Other species like Allium spp. and Foeniculum vulgare are used fresh with tomato and bread. Some wild plant species are consumed fried, especially in the preparation of omelettes. In the Monti Sicani Regional Park, the aerial parts of Diplotaxis erucoides (L.) Dc. are typically fried with eggs and lemon in omelettes, and in the Nebrodi Regional Park the bulbs of Leopoldia comosa (L.) Parl. are sautéed with eggs to prepare traditional dishes as confirmed by [14]. A high number of plant species are consumed raw, most in salads. The aerial parts of Portulaca oleracea L., the young shoots of Clematis vitalba L., the leaves of Nasturtium officinale R. Br. are usually served with a little olive oil, salt and vinegar. Other species like Allium spp. and Foeniculum vulgare are used fresh with tomato and bread. Some plants are consumed as fresh fruit: Fragaria vesca L. in Etna Regional Park and Opuntia ficus-indica (L.) Miller in the Madonie Regional Park. Fruits are also used to make cakes and preserves. Twelve plant species are used to prepare sauces for traditional Sicilian pasta recipes. The most representative are Foeniculum vulgare, Asparagus spp., Sonchus spp., Borago officinalis and Capparis spinosa L. Some aromatic plants are gathered in the wild and consumed steadily throughout during the year. The highly aromatic species Origanum vulgare L., Rosmarinus officinalis and Thymbra capitata (L.) Cav. are examples of such, commonly used to flavour traditional Sicilian dishes. Only two plants species are used for alcoholic beverages: in the Etna and Nebrodi Regional Parks, Mentha pulegium L. and Mentha spicata L. are traditionally used to make liqueurs.

Of the 119 wild plant species in this study, 64 were recorded as having therapeutic effects (Appendix). According to the informants, the dishes prepared and aromatized with these plants have additional health properties, in addition to that of nutrition. When considering 188 wild plant species used in traditional Sicilian cuisine, Lentini and Venza [14] noted that the majority were also used for medicinal purposes by the local populations. Similarities were found between their findings and the results of our study concerning plant species with food/medicinal properties, methods of consumption and medical-use preparation methods. Traditionally, food is often considered to be medicinal in Sicily, as remarked upon by [14], and the food use of a given species may also be seen as curative, depending on the gravity of the disorder. Guarrera and Savo [82] remark that wild food plants are often consumed for their health-giving or medicinal properties also in other parts of Italy. Furthermore, this strong relationship between food and medicinal uses according to [81] and [83], could help in developing of foods for functional, nutraceutical and medicinal purposes.

Clinopodium nepeta (L.) Kuntze was the species most cited by the populations of both the Etna and Nebrodi Regional Parks. The broth obtained from the aerial parts of the species is used to cure internal haemorrhoids. Singh et al. [84] note that the essential oil of Clinopodium nepeta contains 64 pharmacologically active compounds which give the species antibacterial, antioxidant and anti-inflammatory properties.

Cichorium intybus was the most-cited species by the populations of the Madonie and Monti Sicani Regional Parks. The aerial parts of this plant species are commonly boiled and eaten for their good flavour, but also as a bland diuretic, particularly highly appreciated by the local people. The same use was reported by [14]. The plant contains several active principles and is generally retained depurative and healthy as many other plants with a bitter taste. Cichorium intybus is well known in other Italian regions [12, 40, 76, 82], but also in Morocco [85], in Tunisia [78] and in Spain [70].

Several aromatic plants belonging to the Lamiaceae family were particularly highly-appreciated for their therapeutic effects by the informants. Origanum vulgare is an example of such; used in many traditional Sicilian recipes as flavouring in salads, or roast/fried fish and meats, it is also considered to be an important medicinal plant by the local populations, helping to fight colds, flu and stomachache [14]. Several studies carried out in Sicily on wild oregano plants in fact confirmed the antioxidant effect of the essential oils [86‐88]. Other aromatic species, noted for their culinary and therapeutic uses, include Rosmarinus officinalis and Thymbra capitata; the leaves of both of these species are used to flavor vegetables, roast meats etc. A decoction of the aerial parts of rosemary is considered to be particularly effective in the treatment of asthma and gastric disorders; an observation commonly made in both Italian and world literature [89‐92]. An infusion of thyme leaves is thought effective against coughs and colds, and in the treatment of gastrointestinal disorders. Research has found, however, that the quality and quantity of essential oil (which is responsible for the antioxidant and antimicrobial activity of the species) contained in wild rosemary and thyme, can vary considerably and appears to be significantly affected by both intrinsic and extrinsic factors to the species [93‐95].

The culinary use of Laurus nobilis is extremely common throughout the study area. The fresh and dried leaves of the species are used for their distinctive flavor and fragrance. However, the species is also considered medicinal: laurel leaf infusions are used to help digestion, as noted in literature from Sicily [14], Italian regions and other Mediterranean countries [66, 91, 96]. Speroni et al. [97], in a study carried out on the gastro-protective effects and antioxidant properties of leaf extracts of laurel, noted that there seems to be a relationship between the pharmacological effectiveness of these species and its antiradical activity.

The local populations have very good knowledge of the cultivation techniques of small number of wild plant species and have wide experience with many agronomic practices such as soil preparation, crop rotation, sowing, fertilization, irrigation, diseases and pests and harvesting. Organic farming practices are also highy appreciated by the informants. In many towns of the Madonie Regional Park, common chicory and starflower are commonly grown in kitchen gardens and the most used cultivation techniques for these crops are similar to that of spinach and salad rocket. The increasing importance of fennel in the Mediterranean diet has encouraged many aromatic plant producers to breed and commercialize the species in pots. The cultivation of cactus pear is especially widespread in the Etna Regional Park and, on a European level, cactus pear processing is only found in Sicily. The success of this Sicilian production sector is the result of excellent quality fruit, but also in part due to the recent adoption of low-impact cultivation techniques, such as fertilisation, irrigation and thinning, which traditionally were not practiced on this species. In recent years, in the most productive agricultural areas of Sicily, cactus pear crops have been cultivated with irrigation, greatly improving fruit quality.