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Free amino acids in grape juice are important as nitrogen source for yeast strains during alcoholic fermentation. The aim of this research was to determine amino acid profiles in musts from nine grapevine cultivars (six white and three red). The cultivars were located in a homogeneous soil and climatic zone of Bilogora growing hill (West continental region, Prigorje–bilogora subregion), grown on the same training system. The experiment was conducted in vintage 2015. The results showed significant influence of grape cultivar on the amino acids composition in musts of white and red grape cultivars. Arginine was dominant in most analyzed varieties of amino acids. The highest concentration of arginine in white cultivars was measured in Chardonnay must (470.18 mg/L) and in red cultivar must from Saint Laurent (280.65 mg/L). Statistically significant difference was also found in the total amino acid composition of white and red cultivars. The highest concentration of total amino acids in white cultivars was determined in Manzoni juice (1639.51 mg/L) and among the red cultivars in Pinot noir juice (1173.12 mg/L).

Utjecaj globalnog zagrijavanja nije zaobišao niti vinarsku industriju. To se najbolje očituje kroz porast alkoholne jakosti vina te smanjenje ukupne kiselosti što u konačnici dovodi do značajne promjene u senzornim svojstvima vina. Jedna od mogućnosti smanjenja alkoholne jakosti obuhvaća primjenu različitih selekcioniranih kvasaca (Saccharomyces i ne-Saccharomyces). U provedenom istraživanju ispitane su mogućnosti primjene komercijalnih Saccharomyces kvasaca (IONYSWF™, Enoferm RP15 i Uvaferm BDX) sa ciljem smanjenja alkoholne jakosti te povećanja ukupne kiselosti vina sorte Cabernet franc. Po provedenim fizikalno-kemijskim analizama utvrđeno je da je primjena kvasca IONYSWF™ dala vina manje alkoholne jakosti uz naglašeniju ukupnu kiselost. Nadalje, nisu utvrđene značajne razlike u kinetici alkoholne fermentacije među tretmanima, ali su utvrđene razlike u senzornim svojstvima. Prema rezultatima deskriptivne analize vino sorte Cabernet franc (Vitis vinifera L.) proizvedeno primjenom kvasca IONYSWF™ izdvojilo se nešto jačim tijelom te naglašenijim intenzitetom i trajnošću mirisa u kojem su dominirale začinske note i mirisi crvenog voća. Vino navedenog tretmana bilo je ujedno i najbolje brojčano ocjenjeno.

The impact of global warming has not bypassed the wine industry either. This is best manifested through an increase in alcoholic strength, which is accompanied by a decrease in total acidity and significantly affects the sensory properties of wine. One possibility of lowering alcohol strength involves use non Saccharomyces and/or Saccharomyces yeast. The aim of this study was to examine the effect of commercial Saccharomyces yeasts (IONYSWF ™, Enoferm RP15 and Uvaferm BDX) on the reduction of alcoholic strength and increase of the total acidity of Cabernet franc (Vitis vinifera L.) wine. According to the chemical analyzes, it was determined that the wine produced using IONYSWF™ yeast had a lower alcoholic strength with a higher total acidity. Furthermore, no significant differences in alcoholic fermentation kinetics were found between treatments. The wines were sensory different. Descriptive analysis showed that the wine fermented with IONYSWF™ yeast had stronger body without loss of freshness and a more pronounced intensity and lenght of the aroma, which was dominated by spicy notes and aromas of red fruit. This wine was also the best rated.

Slobodne aminokiseline u moštu su važan izvor dušika za kvasce tijekom alkoholne fermentacije. Cilj ovog istraživanja bio je odrediti aminokiselinski profil mošteva devet sorata vinove loze (šest bijelih i tri crne). Sorte vinove loze zasađene su u ujednačenim uvjetima tla i klime vinogorja Bilogora (Regija Kontinentalne Hrvatske, podregija Prigorje-bilogora) te su imale iste agrotehničke uvjete uzgoja. Pokus je postavljen 2015. godine. Rezultati su pokazali signifikantan utjecaj sorte na aminokiselinski sastav u moštevima bijelih i crnih sorti. Najzastupljenija aminokiselina u moštevima devet sorata vinove loze bila je arginin. Najveća koncentracija arginina kod bijelih sorata bila je u moštu Chardonnay (470,18 mg/l), a kod crnih sorata u moštu Lovrijenca (280,65 mg/l). Statistički značajne razlike nađene su između koncentracije ukupnih aminokiselina bijelih i crnih sorata. Najveća koncentracija ukupnih aminokiselina kod bijelih sorata bila je u moštu sorte Manzoni (1639,51 mg/l), a kod crnih sorata u moštu sorte Pinot crni (1173,12 mg/l)

The potential effect of pre-inoculation of processing tomato (Solanum lycopersicum L.) plants with arbuscular mycorrhizal fungi (AMF) on yield and fruit properties was investigated in conventional production. Tomato seeds were sown in seedling trays filled with a substrate non-inoculated (AMF-) or inoculated (AMF+) by selected mycorrhizal strains. Seedlings were transplanted in Terra rossa soil and grown in conditions with mineral fertilization and irrigation. Tomato fruits were sampled at harvest. Tomato plants under both treatments had high levels of mycorrhizal colonization, due to applied inoculum (AMF+) or indigenous (AMF-) inoculum present in the soil. Applied AMF+ treatment increased P and decreased K content in tomato fruits. Content of trace elements such as As and V significantly increased, while Pb content significantly decreased in the fruits of AMF+ when compared to the AMF- treatment. No significant effect of AMF+ treatment was observed on yield, fruit quality (soluble solids, pH, total acidity, fruit firmness), lycopene and antioxidant activity of tomato fruits. The overall results suggest that processing tomato is highly susceptible to the indigenous AMF, while seedlings inoculation with selected AMF improves only total phenolic and P fruit content. This means that AMF have a potential application in commercial processing tomato production, however a targeted adaptation of management decissions is required for more extensive results.

Aroma profiles and phenolic components of white wines made from 'Pošip' and 'Škrlet' (Vitis vinifera L.) both native Croatian, non-aromatic grape varieties enhances the knowledge about these varieties, prepared without maceration (control) and subjected to the pre-fermentative cold maceration (CM). Individual phenolic compounds in wines were determined by high-performance liquid chromatography (HPLC) system, while total phenolics and flavan-3-ols in wines were determined by spectrophotometric methods. CM had the significant impact on the total phenolic and flavan-3-ols composition of 'Škrlet' wine. The significant increase of some individual phenolic compounds was observed in 'Pošip' wine. Volatile aroma compounds in wines were determined by gas chromatography (GC) with the previous extraction on the solid phase micro extraction (SPME). The primary aroma compounds, i.e. terpenes were under the significant influence of CM process in 'Škrlet' wine. Aroma profiles, based on the content of 24 specific compounds, grouped in eight aroma series that contribute to wine odor were developed. CM significantly increased five aroma series in 'Škrlet' wine and only three in 'Pošip' wine.

Common bean (Phaseolus vulgaris L.) is an important legume crop. In Croatia, many different common bean landraces are grown mostly on small farms and in kitchen gardens. The aim of this research was to determine and compare nutrient content of Croatian common bean landraces and to test the existence of the relationship between common bean nutrient content with origin of accessions. A total of 226 common bean accessions from all over Croatia were collected, grown in unreplicated field trial at the experimental field in Zagreb, harvested and analyzed for nutrient content. Results showed high nutrient content, but clear difference between Mesoamerican and Andean gene pool regards the nutrient profile of Croatian common bean landraces was not determined. Regardless of gene pool, the average nutrient content in dry weight of Croatian common bean landraces was in range: 3.13–3.92% N, 0.49–0.57% P, 1.38–1.66% K, 0.34–0.42% Ca, 0.17–0.20% Mg, 63.75–75.77 mg Fe∙kg-1, 13.55–19.94 mg Mn∙kg-1 and 24.98–29.32 mg Zn∙kg-1. Present research provides a solid basis for future breeding programs and improvement of common bean traits.

Organic amendments are often reported to improve soil properties, promote plant growth, and improve crop yield. This study aimed to investigate the effects of the biochar and compost produced from sewage sludge and olive pomace on soil hydraulic properties, water flow, and P transport (i.e., sorption) using numerical modeling (HYDRUS-1D) applied to two soil types (Terra Rosa and Rendzina). Evaporation and leaching experiments on soil cores and repacked soil columns were performed to determine the soil water retention, hydraulic conductivity, P leaching potential, and P sorption capacity of these mixtures. In the majority of treatments, the soil water retention showed a small increase compared to the control soil. A reliable fit with the modified van Genuchten model was found, which was also confirmed by water flow modeling of leaching experiments (R2 0.99). The results showed a high P sorption in all the treatments (Kd 21.24 to 53.68 cm3 g−1), and a high model reliability when the inverse modeling procedure was used (R2 0.93–0.99). Overall, adding sewage sludge or olive pomace as compost or biochar improved the Terra Rosa and Rendzina water retention and did not increase the P mobility in these soils, proving to be a sustainable source of carbon and P-rich materials.

Soil is a non-renewable resource, so it should be taken care of it. High quality food with sufficient yield for a growing human population can be produced only if plant nutrients are added to the soil by fertilizers to increase soil fertility, but the fertilizers have to be used economically, with the aim of raising the nutrient content available in the soil in order to meet plants' needs. The goal of the present investigation was to determine the effect of application of organic and mineral fertilizers as well as the effect of research environment on micronutrient content in red beet root. A field trial (2003-2005) was set up in a hilly part of Croatia according to the Latin square method, with four types of fertilization (control, 50 t stable manure*ha-1, 500 and 1,000 kg NPK 5-20-30*ha-1). After digestion of plant material with concentrated HNO3, iron, manganese, and zinc were determined by an atomic absorption spectrophotometer (AAS). The highest average red beet root micronutrient contents (270 mg Fe*kg-1 in dry matter, 96 mg Zn*kg-1 in dry matter, and 53 mg Mn*kg-1 in dry matter) were determined in the first research environment (Brašljevica in 2003) with low potassium soil content. There was a general decreasing trend in contents of the studied micronutrients (Fe, Mn and Zn) with NPK 5-20-30 fertilization (and by application of high doses of potassium), certainly due to antagonistic activity with potassium. It is suggested to fertilize with both 500 kg NPK 5-20-30*ha-1 and microelement fertilizers.