In this research, rehydration behavior of dried figs was studied at different temperatures (25, 60, 70, 80, and 90oC). The rehydration kinetic was examined using the four most frequently used empirical models, namely, Weibull, Peleg, first-order, and exponential association models. The Weibull model gave the highest coefficient of determination (R2) and the lowest values of root mean square error (RMSE), sum of squared error (SEE), and chi-square (X2) was considered the best. In all models examined, the equilibrium moisture content showed statistically significant differences as compared to the rehydration temperature. The temperature dependence of kinetic constants was described in terms of Arrhenius relationship. The average activation energy for the four models was 24.362 kJ mol-1. During the rehydration process hardness of dried figs decreased, which was further confirmed by microscopic evaluation. Scanning electron microscopy (SEM) images of rehydrated figs indicated porous structure proposing the presence of free water.

Dried figs collected from various exporting companies (2, 461 samples) and local stores (219 samples) were analyzed using reverse-phase high-performance liquid chromatography (RP-HPLC) to determine and compare the incidence of aflatoxins, the effectiveness of the regulation limits and monitoring system to select non-compliant samples and the mean daily aflatoxin exposures. The incidence rates of aflatoxin contamination were higher in the domestic samples (47.5%) than in the samples intended for export (23.6%). According to the European regulation limits (2 ng g-1 for aflatoxin B1 and 4 ng g-1 for total aflatoxin, sum of B1+B2+G1+G2), non-compliant samples were 6 and 24.2% of the dried figs for export and domestic market, respectively. The respective rates of 2.2 and 16.4% were obtained with the national limit. The dietary intakes of aflatoxins through the consumption of dried figs were calculated as 1.27 and 0.2 ng kg-1 body weight×day for domestic market and export, respectively. Dried figs contaminated with high levels of aflatoxins can lead to acute and chronic human toxicities. Reducing contamination and exposure to an acceptable level by the implementation of strict periodic monitoring and application of effective new prevention measures might also help to decrease the significant health and economic risks in exported and domestic commodities.

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The present study was carried out to investigate the occurrence of total mycobiota and Aspergillus species at different stages of fig production and processing in Iran. In the meantime, the potential of different culture media for isolation of fungal species from figs was also investigated. The mycobiota of 389 samples of dried fig were studied. Total fungal counts ranged from <2 to 6.74 log10 CFU g-1. In general, the predominant species were Aspergillus niger aggregate, Aspergillus flavus, Acremonium spp. and Mucor spp. In percentages of 90.9%, 63.7%, 54.6% and 36.4% infection, respectively. Other Aspergillus spp. and Mucor spp. Corresponded to 36.7% and 28.3% infection, respectively. The lowest contamination was observed in dried figs. The predominant fungi were Alternaria spp. and Penicillium spp. (9.1% infection). On average, Aspergillus spp. comprised 34.4% of the total fungal population. Aspergillus niger aggregate was detected in 99%, and A. terreus was present in 11.3% of total samples. The results revealed that poor hygienic conditions in fig harvesting, drying procedures, collecting sites, sorting and packaging plants caused higher mould contamination and risk of the A. flavus growth in dried fig production in Iran. As the result obtained from this study, using more than one culture media for isolation of A. flavus is recommended.

Crystallization is an important phenomenon that affects some quality attributes such as appearance, texture and shelf life in many food materials. Sugar crystallization is a major challenge for dried fruits such as figs with low moisture levels and high sugar contents. In this study, the effect of glycerol and glucose syrup (DE=38) on the amount of sugar crystallization in figs with different moisture contents was investigated using X-ray diffraction. The addition of glycerol and glucose syrup increased equilibrium moisture content and reduced sugar crystallization significantly. In the presence of glycerol, sugar crystallization was one third of the control. Glycerol also had greater effect compared to glucose syrup. Changes observed due to the presence of glycerol and glucose syrup could be attrinuted to the hygroscopic behavior of these additives and their ability to keep more water at a specific water activity.

The 39 cultivars of Iranian figs cultivated in Agricultural Jahad research center of Varamin. collections have been morphologically evaluated. 31 quantitative and qualitative characters were assessed in this procedure. According to results of analysis variance all the characters in examined cultivars were significant, showing high variability in some characters. Results of simple correlation analysis showed the existence of significant positive and negative correlation among some important characters. Also, factors analysis showed that most of growth habitat like shoot length, number of internodes and length of 1/3 and 2/3 internodes of apical and medium characters constitute the main factors. Effective characteristics categorized in eleven factor accounted 77.6 of total variance. For each factor eigen value more than 0.5 was considered significant. Cluster analysis was performed using these 11 factors and cultivars in the distance of 13 were divided into 5 main clusters. These groups were mainly distinct in growth habitat and leaf size.

‘Smyrna’ type figs (Zidi ‘ZD’: dark fruit and Thgagli ‘THG’; Bidhi ‘BD’ and Khedri ‘KHD’: white fruit) originated from two areas of fig production in Tunisia were subject to physico-chemical description and spectrophotometric analysis for their sugar (glucose, fructose and sucrose) and organic acid (citric and malic) contents. Fruit weight ranged between 54 and 82 g, fruit width between 47 and 59 mm, ostiole width between 5.5 and 13.7 mm, total soluble solids (TSS) between 16.1 and 18.4% and titratable acidity (TA) between 2.0 and 4.7 mEq/kg of fresh weight (FW). Tunisian figs were characterized by the predominance of glucose (6.3 g/100g FW) and fructose (5.1 g/100g FW). Citric acid (0.38 g/100g FW) was the major organic acid in all cultivars and almost three times higher than malic acid (0.13 g/100g FW). Differences between cultivars were significant (p£0.05). Highly significance was recorded related to malate content contrary to citrate levels which were almost the same in the four cultivars. Purple black ‘ZD’ fruit was the richest on reducing sugars and malic acid and is more suitable for fresh consumption. ‘BD’ fig had the most interesting physico-chemical properties with round shape, light skin colour and highest concentrations on soluble solids and is better adapted to drying Compared to common fruits, figs are exceptionally rich on sugars responsible in major part of enhancing food ration and intake of people living in the Mediterranean region. Quality parameters described in the present work are fundamental to judge about the potential of local cultivars. Considering quality a prime target for plant breeders, present data could help for fig breeding and cultivars selection.