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The production system, especially fertilisation has an important effect on yield and quality of strawberries. In the present study, plants were fertilized with different doses of nitrogen (0–100% recommended doses), calcium chelate, as well as nano fertilizer Lithovit. Strawberry cultivar ‘Clery’ yield and quality parameters (fruit color and firmness) including nutritional indicators (total soluble solids, sugars, organic acids, phenolic and volatile compounds) were monitored. Volatiles were identified and monitored using headspace solid phase microextraction and analysed using gas chromatograph-mass spectrometry (SPME/GC-MS) and sugars, organic acids, and phenolic compounds with high performance liquid chromatography. Organic acids and phenolic compounds were detected with mass spectrometer (HPLC/MS). Both nitrogen and calcium fertilisation had altered sugars, organic acids, volatile and phenolic contents in strawberry fruits. Fertilisation with higher doses of nitrogen and calcium increased the content of unpleasant aromas aldehydes hexanal (up to 3.8-fold) and (E)-2-hexen-1- (up to 3.7-fold). The content of fruity esters was uppermost in fruits fertilised with nano-fertiliser Lithovit (up to 2.3-fold). Fertilisation with N and Ca decreased the strength of ketone and terpenoids fruity aroma. The highest content of total phenols, as well as all individual hydroxycinnamic and hydroxybenzoic acid derivatives were obtained in the nano-fertiliser Lithovit treatment. Fertilisation, especially with nitrogen, had mostly negative impact on strawberry flavour while nano-fertilization with Lithovit improved strawberry phenolic content and aroma.

Consumption of common dandelion (Taraxacum officinale agg.) can pose a risk when foraged in agroecosystems like vineyards where pesticides are frequently used. The aims of our study are to evaluate whether dandelion foraged in vineyards with different management practices (integrated pest management, organic, and biodynamic) in spring is suitable for consumption and to assess whether the contents of selected pesticide residues (PR) in integrated vineyards in dandelion vary throughout the seasons. Young dandelion leaves were sampled in spring, summer, and autumn in integrated vineyards, while in spring also in organic and biodynamic vineyards. The selected PR was analyzed using GC-MS/MS and LC-MS/MS, using extraction with acetonitrile. The method was validated on a dandelion matrix according to international guideline SANTE 11312/2021. Despite the use of many pesticides in integrated vineyards, only tebuconazole was detected in spring in one sample (0.005 mg/kg), while no PR was detected in dandelion from organic and biodynamic vineyards. However, at summer sampling seven different PR were detected, of which the kresoxim-methyl maximum residue limit was exceeded in five samples (0.012–0.029 mg/kg), while in autumn no PR was detected. Based on this study, it seems that dandelion leaves foraged in vineyards in spring could be unproblematic for consumption.

Pesticide residues and heavy metal concentrations were determined in two depths (0–20 and 20–40 cm) of Chromic Cambisol in 69 vineyards in the Slovenian winegrowing region of the Karst. Similarly, pesticide residues and heavy metal concentrations were also determined in two depths of Calcaric Cambisol in 11 vineyards in the other Slovenian and Croatian winegrowing regions of Istria. The topsoil (0–20 cm) was analysed for the presence of 176 different pesticidal active substances using two multiresidue analytical methods: (a) gas chromatography coupled with mass spectrometry (GC/MS) and (b) liquid chromatography coupled with tandem mass spectrometry (LC/MS/MS). Seven active substances (five fungicides and two insecticides) were detected in the soil samples. Their concentrations were compared with the maximum concentrations observed in the vineyards of the winegrowing regions of France, Italy, and Spain. In addition to pesticides, the soil samples were analysed for the presence of nine heavy metals commonly detected in vineyard soils. The concentrations of arsenic, cadmium, cobalt, chromium, copper, molybdenum, nickel, lead, and zinc were below the critical thresholds set by Slovenian legislation, with the exception of one soil sample in which the Cu concentration exceeded the critical threshold. Compared with the maximum concentrations measured in other vineyard soils in Spain, Italy, and France, the heavy metal concentrations in the vineyard soils of Karst and Istria were lower. Both the heavy metal concentrations and the residual concentrations of pesticidal active substances in the vineyard soils of the Karst and Istria regions were significantly lower than the concentrations that are occasionally discussed in the literature.

The aim of this research was to investigate the effects of pre-fermentative maceration, Saccharomyces and non-Saccharomyces yeasts during alcoholic fermentation, and antioxidant additions (sulfur dioxide and glutathione) at bottling on the compositions of aroma and phenolic compounds of white wine Pošip (Vitis vinifera L.). Additionally, for the first time the insight in volatile thiol precursors in Pošip grape was given, wherein higher concentrations of glutathionylated thiol precursors in comparison to cysteinylated ones were determined. Regarding the applied practices, significant differences among produced wines were established: pre-fermentative maceration resulted in a decrease of 3-sulfanylhexyl acetate (3SHA) and a slight increase of C6 compounds; indigenous yeasts produced higher concentrations of terpenes and esters, while sequential fermentation with Torulaspora delbrueckii also influenced higher concentrations of esters. Most abundant phenolic compound was caffeic acid, except for wine produced by indigenous yeasts where trans-caftaric acid was predominant. Finally, combination of higher SO2 and glutathione resulted in higher concentrations of thiols.

Honey bee (Apis mellifera carnica) colonies were placed in two apple orchards treated with the insecticides diazinon and thiacloprid and the fungicide difenoconazole in accordance with a Protection Treatment Plan in the spring of 2007. Pollen and bee bread were collected from combs inside the hives. The residue of diazinon in pollen loads 10 days after orchard treatment was 0.09 mg/kg, and the same amount of residue was found in bee bread 16 days after treatment. In pollen loads 6 days after application 0.03 mg/kg of thiacloprid residues and 0.01 mg/kg of difenoconazole were found on the first day after application. Possible sub-lethal effects on individual honey bees and brood are discussed.

This study aimed to determine the effects of diammonium phosphate (DAP) and yeast autolysates (organic nutrients) added during alcoholic fermentation on the content and profile of aroma compounds in Sauvignon Blanc wines. Sequential additions of either DAP or organic nutrients were applied mainly during the first half of fermentation, increasing yeast assimilable nitrogen (YAN) from an initial 124 mg N/L to final concentrations of 208 and 209 mg N/L for DAP and yeast autolysates, respectively. Control musts were fermented without nutrient supplementation. All treatments were fermented using commercial yeast strain. Varietal thiols, ethyl and acetate esters, higher alcohols, glutathione (GSH), and YAN were monitored at early, mid, and late stages of fermentation, as well as in the final wines. Varietal thiols were formed at early stages of fermentation in all treatments; however, concentrations of both 4-methyl-4-sulfanylpentan-2-one (4MSP) and 3-sulfanylhexan-1-ol (3SH) were higher in wines supplemented with organic nutrients comparing to DAP and control. Compared to the control, DAP and organic nutrient supplementation increased ethyl ester concentrations in wine by 40.2% and 26.9%, respectively. Both nutrient treatments also resulted in higher acetate ester concentrations, while total higher alcohols were reduced by 19.1% with DAP and 12.1% with organic nutrients. No significant differences in GSH concentrations were observed among treatments. Sensory analysis revealed that wines supplemented with DAP achieved the highest scores for tropical aroma, varietal aroma, and overall quality. Overall, sequential supplementation with either inorganic or organic nitrogen positively influenced fermentation kinetics and aroma compound composition, resulting in improved varietal expression of Sauvignon Blanc wines. However, in low-YAN musts, DAP had a greater impact than organic nitrogen sources and should therefore be considered a key strategy for ensuring an adequate yeast nitrogen status.

Wine aroma is influenced by a number of volatile compounds. This article describes the validation of the method for 26 volatile compounds found in wine. Volatile compounds were determined with discontinuous liquid-liquid extraction and GC-MS detection. It was determined, that the method is linear with square correlation coefficient ranging from 0.961 to 0.999.  Limits of quantitative determination range from 0.52 mg/L to 14.8 mg/L. Recoveries range from 71.1% to 105.7% except for two compounds with lower recoveries. Measurement uncertainty ranges from 5.0% to 28.9%. According to the validation, the method is suitable for the determination of at least 24 volatile compounds common to wine. A practical method application was presented on Zelen wine variety from two different production procedures. 

Wine aroma is influenced by a number of volatile compounds. This article describes the validation of the method for 26 volatile compounds found in wine. Volatile compounds were determined with discontinuous liquid-liquid extraction and GC-MS detection. It was determined, that the method is linear with square correlation coefficient ranging from 0.961 to 0.999. Limits of quantitative determination range from 0.52 μg/L to 14.8 μg/L. Recoveries range from 71.1% to 105.7% except for two compounds with lower recoveries. Measurement uncertainty ranges from 5.0% to 28.9%. According to the validation, the method is suitable for the determination of at least 24 volatile compounds common to wine. A practical method application was presented on Zelen wine variety from two different production procedures. Na aromo vina vplivajo številne hlapne spojine. Ta članek opisuje validacijo metode za 26 hlapnih spojin, ki jih najdemo v vinu. Hlapne spojine so bile določene z diskontinuirano ekstrakcijo tekoče-tekoče in GC-MS detekcijo. Določili smo, da je metoda linearna, z razponom kvadrata korelacijskega koeficienta od 0,961 do 0,999. Meje kvantitativne določitve imajo razpon od 0,52 μg/L do 14,8 μg/L. Izkoristki imajo razpon od 71,1% do 105,7%, razen za dve spojini, katerih izkoristek je nižji. Merilna negotovost ima razpon od 5,0% do 28,9%. Z ozirom na validacijo lahko potrdimo primernost metode za določanje vsaj 24 hlapnih spojin značilnih za vino. Praktični prikaz uporabe metode smo predstavili na vinih sorte Zelen iz dveh različnih postopkov pridelave.

Monitoring ostankov pesticidov v kmetijskih pridelkih kaže, da so ostanki ditiokarbamatov tudi v Sloveniji med najpogosteje ugotovljenimi. V letih od 2003 do 2005 smo v poljskih poskusih ugotavljali vpliv izbora fungicidov in časa po zadnjem škropljenju krompirja na vsebnost ostankov v gomoljih krompirja. Primerjali smo štiri obravnavanja: enostransko in izmenično škropljenje s fungicidi na osnovi ditiokarbamatov, škropljenje brez ditiokarbamatov in neškropljeno kontrolo. Po končanih škropljenjih smo v zaporednih vzorčenjih naključno jemali vzorce po 10 grmov na polju in po 5 kg krompirja v skladišču. V drugem poskusu smo preučevali vpliv medvrstne razdalje na vsebnost ostankov ditiokarbamatov v gomoljih na različnih globinah. Primerjali smo medvrstne razdalje 66 cm, 75 cm in 90 cm pri sortah Carlingford, Agria in Bright. Razporeditev gomoljev v grebenih smo ugotavljali z napravo za tridimenzionalno merjenje oblike grebena in položaja gomoljev v grebenu. Vzorčili smo gomolje po plasteh 0-5 cm, 5-10 cm in >10 cm in pobirali gomolje posamično. Vzorce krompirja smo na ostanke ditiokarbamatov analizirali s plinskim kromatografom, sklopljenim z masnim spektrometrom. Ostanke ditiokarbamatov v gomoljih smo ugotovili le v letu 2003. Rezultati kažejo, da so okoljske razmere ključen dejavnik za pojavljanje ostankov v gomoljih in imajo lahko celo večji vpliv kot količina uporabljene aktivne snovi ali drugi tehnološki ukrepi. Upoštevanje dobre kmetijske prakse v večini let omogoča pridelavo krompirja brez ostankov ditiokarbamatov. V neugodnih letih lahko najdemo ostanke, kljub pridelavi v skladu s tehnološkimi priporočili in upoštevani karenci ob izkopu krompirja.

In the period from 2005 to 2009 225 samples of apples, lettuce and potatoes from Slovene producers included in integrated pest management (IPM) were analysed for plant protection product (PPP) residues. The samples were analysed for the presence of more than 200 different active compounds using four analytical methods. In 38.7% of apple samples residues were not detected, 58.6% of apple samples contained residues lower than or equal to Maximum Residue Levels (MRLs) while 2.7% of apple samples exceeded MRLs. In 84.6% of lettuce samples residues were not detected, 12.3% of lettuce samples contained residues lower than or equal to MRLs while 3.1% of lettuce samples exceeded MRLs. In 98.0% of potato samples residues were not detected, 2.0% of potato samples contained residues lower than or equal to MRLs and no potato samples exceeded MRLs. Multiple residues were found only in apples and lettuce. The trend observed during the years was the decrease of sample portion of samples containing multiple residues in apples from 2005 to 2008. The most frequently found active substance in apples and lettuce was dithiocarbamates. In potato only phosalone was found.