S. Mahmoudi^1,2, M. Khali², A. Benkhaled³, I. Boucetta¹, Y. Dahmani³, Z. Attallah³ and S. Belbraouet^4
1 Department of Agronomic Sciences, University “Med Boudiaf”, M’sila, Algeria
² Department of Food Sciences, University “Saâd Dahleb”, Blida, Algeria
³ Department of Microbiology and Biochemistry, University “Med Boudiaf”, M’sila, Algeria
⁴ Faculty of Health Sciences and Community Services, University of Moncton, Canada

SUMMARY Ficus carica L. (Moraceae) is a wild spread tree including more than 600 cultivars with different phenotypic characteristics. Their fruits are a good natural source of nutrients, minerals, and phytochemicals, which may improve human health. The pomological characteristics of nine Algerian cultivars of fresh figs were determined using descriptors resulting from the IPGRI and CIHEAM list. The consumer test was carried out using an in-store consumer test. The proximal components (dry matter, ash, titratable acidity, crude protein (Kjeldahl), ascorbic acid, and carbohydrates) were estimated using the AFNOR and Dubois methods. Minerals (Ca, K, and Na) were analyzed using a flame spectrophotometer. Phosphorus, phenolic, flavonoid, anthocyanin, and condensed tannin concentrations were quantified by UV-spectrophotometer. The antioxidant capacity was evaluated using the 2, 2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay. The pomological results obtained made it possible to discriminate between the different fig cultivars. Skin color results indicate two groups (light skin and dark skin groups). The consumers preferred ‘Boughandjo’, ‘Bither’, and ‘Bakkor Biadh’, with high percentages of acceptance (68.75, 70.31 and 75%). Figs are a good source of carbohydrates (especially ‘Safra’ pulp [26.02±0.63 g 100 g-1 Fresh weight]), vitamin C (10.67±0.31 mg 100 g-1 Fresh weight for ‘Onk Elhamam’ peel), and potassium and calcium (266.67±2.78 and 125.44±3.37 mg 100 g-1 Fresh weight for ‘Bakkor Khal’ peel, respectively). In the majority of the tested cultivars, peels exhibited higher phenolic (1.63 vs. 1.11 mg gallic acid equivalents g-1 Fresh weight), flavonoid (147.76 vs. 83.82 µg quercetin equivalents g-1 Fresh weight), anthocyanin (64.82 vs. 41.72 µg cyanidin-3-rutinoside equivalents g-1 Fresh weight) and condensed tannin (6.08 vs. 2,06 µg catechol equivalents g-1 Fresh weight) levels and antioxidant activities (18.91 vs. 29.51 mg mL-1) than pulps. Peels of dark cultivars showed higher phytochemical and antioxidant properties than those of light cultivars. Antioxidant activity was correlated with total phenolic and condensed tannin concentrations (r=0.521 and 0.659). The pomological characterization and consumer tests reported here are important for allowing farmers to judge about the potential of the tested cultivars and could be helpful during fig breeding and cultivar selection. Based on their diversity, tastes, nutritional and phytochemical attributes, we recommend figs (especially those with dark skin) as healthy food. Keywords consumer test, cultivars, descriptors, minerals, Moraceae, phenolics, proximal components

Significance of this study What is already known on this subject? The diversity of figs, their nutritional contribution in the diet, and their impact on human health has been studied for many cultivars around the world. Nevertheless, there are more than 600 fig tree cultivars. Here we describe novel cultivars from the Mediterranean region. We highlighted the nutritional value and phytochemical characteristics of fig peel because the majority of consumers tend to peel figs before consumption. What are the new findings? By pomological characterization, we were able to discriminate between the studied cultivars. Also, using a sensory test, we found that consumers prefer some unknown and underutilized cultivars (‘Bither’, ‘Boughandjo’, ‘Zarrouk’, and ‘Hamra’). Fig peel, especially of dark skin cultivars, is an important source of minerals such as calcium and potassium and of phytochemicals, which have a positive impact on human health. What is the expected impact on horticulture? Our data will likely help farmers to select the most appropriate cultivars for fresh consumption, especially those of higher yield (e.g., ‘Boughandjo’) and precocious types (e.g., ‘Bither’). Our data will also help farmers identify those cultivars with the greatest nutritional value and phytochemical properties.

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Received: 4 April 2017 | Accepted: 21 July 2017 | Published: 24 April 2018 | Available online: 24 April 2018