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The aromatic profile of volatiles in dried figs varieties Bružetka Bijela and Zimnica were characterised by headspace solid-phase (HS-SPME) procedure with gas chromatography-mass spectrometry analysis (GC-MS). The volatile compounds were distributed by distinct chemical classes, including alcohols, aldehydes, esters, terpenic compounds, and other compounds. The figs were dried in a pilot plant cabinet dryer. Prior to drying process, figs were pre-treated by sulphur dioxide, immersed in solution of citric acid and ascorbic acid, respectively. Several mathematical thin-layer drying models, available in the literature, were fitted to experimental data of figs, implementing non-linear regression analysis techniques. The results showed that pre-treatments of figs decrease significantly the drying time. The best thin-layer drying model in terms of fitting performance was Wang and Singh model. The major volatile compound in dried figs was benzaldehyde. After benzaldehyde, the most abundant aldehyde in dried figs was hexanal. The comparison among dried figs showed the highest abundance of aldehydes, in general, in non-treated (control) dried figs compared to pre-treated samples. Furthermore, ascorbic acid was the most efficient in preserving esters and alcohols in case of Bružetka Bijela, whereas in case of Zimnica, sulphur dioxide was in advance compared to ascorbic acid. Ethyl acetate was the most abundant ester found in dried figs. Among other compounds, 2-butanone,3-hydroxy was the most abundant identified volatiles. Linalool, as the only identified terpen, was in case of both dried fig varieties, preserved by immersion into ascorbic acid. The immersion into citric acid has not been so successful in volatiles conservation.

Abstract:The conversion of old black pine plantations into ecologically more stable broadleaf forests is an important goal in many Mediterranean countries. Six experimental plots split between more and less productive sites were established in the sub-Mediterranean climate zone of south-western Slovenia in an area of mostly pure black pine stands. In November 2012 they were planted with six native broadleaf species (Celtis australis, Quercus petraea, Fagus sylvatica, Prunus avium, Juglans regia and Acer pseudoplatanus). The test plantations were intended to become small initial nuclei from which the introduced broadleaf species could later spread naturally into the old and partly degraded pine plantations. Seedling condition was assessed one year after planting. Based on their high survival rates after the first growing season, all tested species except F. sylvatica showed promising potential for future conversion of old pine stands in the Slovenian Karst region. However, the results of one growing season only are insufficient to draw firm conclusions. Of all planted species P. avium had the highest survival rate (95%) and was least susceptible to poor field conditions. Without exception, all species showed lower survival rate on the less productive site. Unlike other species, P. avium and J. regia seedlings had considerable height increment, while F. sylvatica had the lowest. From the results we can assume that perhaps old pine stands in the area have already considerably improved soil conditions and thereby enabled the introduction of broadleaves.Additional key words: planting broadleaves, forest conversion, survival rate, height increment, tree vigour

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Questions What is the long‐term impact of deer browsing on the diversity of the herbaceous layer and tree species regeneration? Which parameters of regeneration of the tree species regeneration and the herbaceous layer best indicate browsing impact? Study site Dinaric Mountains, Slovenia. Methods We studied the long‐term impact of red deer on mixed temperate forests by comparing the tree species regeneration and herbaceous layer vegetation under two treatments: deer present, no deer. We analyzed the regeneration of trees older than one year up to a diameter at breast height of 10 cm (categorized into five height classes) and the cover abundance of plant species in the herbaceous layer (<50 cm). Results There were no significant differences between the treatments in the number of tree species regeneration. Browsing impact on the most abundant tree species—European beech, silver fir and sycamore—varied, indicating differences in palatability. When deer were present, the number of silver fir regenerating was significantly lower in all height classes, and regeneration of European beech specimens shorter than 50 cm was more abundant, while for sycamore shorter seedlings (<20 cm) were more abundant, and regeneration of taller specimens (≥50 cm) was significantly less abundant. The reduction of tree species diversity during natural regeneration is evident. There were no significant differences between the treatments in the number and diversity of plant species in the herbaceous layer; however, the abundance of 13 plant species differed significantly between the treatments. Deer reduce the density of tree species saplings due to long‐term browsing and thus indirectly increase tree species diversity in the regeneration up to 20 cm in height and plant species diversity in the herbaceous layer. Conclusions We documented the direct and indirect impact of deer on the diversity of tree species regeneration, but only found an indirect influence on the diversity of the herbaceous layer. The height structure of palatable tree species regeneration appears to be the most appropriate indicator of browsing impact. The observed browsing impact leads to the complete dominance of European beech in the tree species composition of forest stands.

Summary The aromatic profile of volatiles in fresh figs (FF), fresh figs frozen in liquid nitrogen (NF) and dried figs (DF) (dark variety Petrovača Crna) was characterised by HS–SPME followed by GC–MS. Figs were dried in a pilot plant cabinet dryer using different pre‐treatments to preserve the dried fruit: sulphuring and immersion in a solution of citric acid and ascorbic acid (separately). The adaptability of thin‐layer drying models to whole figs was investigated. Fresh figs and fresh figs frozen in liquid nitrogen differed mainly in the amount of aldehydes. The highest abundance of volatile compounds in dried figs was found in figs pre‐treated with sulphur dioxide and the control, compared to samples immersed in the acid solutions. Preservation was the most successful for the group of terpenes and terpenic compounds, quite good for some esters and ketones, whereas aldehydes were not affected by the used pre‐treatment.

The article title has been published with misspelled entry. The word "sesonal" should be "seasonal". The correct title should be "Volatile compounds in Nanos cheese: their formation during ripening and seasonal variation", as shown above.The online version of the original article can be found at http://dx

Peaches are consumed worldwide and have great market demand. Compared to apricots, the volatiles defining the typical peach aroma are still poorly analytically characterized. The aim of our study was to determine the impact of the stage of ripening, sample storage conditions, and type of fiber coating and extraction glassware on peach aroma compounds. The peach aroma components were extracted by headspace solid-phase microextraction (HS-SPME) and with the application of a specific fiber (DVB/CAR/PDMS fiber) that retained the main group of volatiles present in peaches. Artisan-made glassware that enabled bigger sample loads was used. It was found that its application provided a 3-fold higher extraction of aromatic compounds on average. Significant differences were also found when the same peach pulp was analyzed fresh or frozen (in liquid nitrogen or in the freezer at -16 °C). In fresh peaches, a higher amount of some alcohols and important esters was determined. Liquid nitrogen had a positive impact on hexanal and (E)-2-hexenal, whereas the storage of samples in the freezer had a major impact on most other aldehydes, as well as limonene. The study revealed the importance of sample preparation and storage on the overall aromatic profile of peaches.