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An innovative approach to stimulate the production of plant secondary metabolites (PSM) is the use of encapsulated bioactive agents. Zinc-alginate microparticles (microspheres (ALG/Zn) and microcapsules (CS/ALG/Zn)) were applied near the root zone of soilless cultivated strawberries (Fragaria × ananassa Duchesne) to ensure a constant supply of an essential micronutrient zinc ions throughout the whole period of maturation. Both, ALG/Zn and CS/ALG/Zn had a positive effect on PSM (total polyphenols, total flavonoids, total anthocyanins, and flavan-3-ols) synthesis and increased antioxidant activity in two strawberry varieties (Albion and San Andreas). Treatments with Zn-alginate microparticles resulted in no visible damages on the plant and fruits. A two-year study revealed an increase of ~ 34% in total polyphenolic compounds and ~ 23% in total flavonoids in the San Andreas variety. The highest increase in antioxidant activity (ABTS (~ 37%) and DPPH (~ 38%)) was observed in the San Andreas variety treated with CS/ALG/Zn. Respectively high increase in anthocyanins was observed in both varieties (~ 54% and ~ 61%, respectively) treated with CS/ALG/Zn. Treatments with zinc alginate microparticles resulted in a successful stimulation of PSM synthesis and increased strawberries' nutritive value. Encapsulation of zinc ions proved to be simple, sustainable, and environmentally favorable to produce strawberries fortified with important bioactive compounds.

The layer-by-layer application of biopolymeric coatings to mandarin fruits as a postharvest treatment to improve fruit coating efficacy has been reported. A single 1 % (w/v) chitosan application was evaluated, and polyelectrolyte complexes such as 1.5 % (w/v) alginate/chitosan, 1 % (w/v) hydroxypropyl methylcellulose/chitosan, and 0.2 % (w/v) locust bean gum/chitosan were applied to mandarin fruits. The quality of coated mandarin fruits was observed at temperatures: 20 ± 2 °C (up to 10 days) and 5 °C (up to 28 days). Changes in the fruit metabolism were observed by evaluating bioactive compounds (polyphenolic compounds and flavonoids), antioxidant activity, and organic acids during the preservation of mandarin fruits. All of the tested combinations of layer-by-layer coatings significantly impacted the quality of mandarin fruits throughout storage, both at room temperature and cold storage, respectively. The overall best performance was observed for a layer-by-layer hydroxypropyl methylcellulose/chitosan coating in terms of visual aspects, bioactive compounds, antioxidant activity, and organic acids content.

In addition to the production of albumin cheese, biogas and whey powder, whey has also been used as a raw material for the production of alcoholic beverages. The aim of this research was to investigate the potential of using Istrian albumin cheese whey in the production of whey distillate. Three batches of Istrian albumin cheese were produced in a small-scale cheese plant. The remaining whey after the production of albumin cheese was fermented using Kluyveromyces marxianus subsp. marxianus for 5 days and then distilled. In the whey samples before and after fermentation, the content of total solids, protein, milk fat and lactose was determined. The ethanol content and the composition of volatile compounds in the distillate was determined. The content of all components of the chemical composition of whey, except for the content of fat, decreased during fermentation. In the whey distillate with an alcohol content of 35%, the following compounds were determined: acetaldehyde, methanol, n-propanol, i-butanol, n-butanol, 3-methyl-1-ol, 2-methylbutan-1-ol and ethyl-lactate. The distillate obtained confirmed the potential of using whey for the production of spirits. However, further research is needed due to the potential presence of the harmful effects of certain volatile compounds on human health.

Odoriferous compounds 3-sulfanylhexanol (3-SH) and 3-sulfanylhexyl acetate (3-SHA), produced during the fermentation from precursors present in grape and must, are the most important representatives of the group of varietal thiols with a crucial role in the formation of the aroma of certain wines and a very low odor detection threshold. Due to their reactivity, polarity, high boiling points, and very low abundance in wine, isolation, and quantification of varietal thiols represent a tedious task. Procedures for the derivatization of varietal thiols in Sauvignon Blanc wine were conducted and optimized, with emphasis on the base selection, influence of pH value and duration on the outcome of derivatization, addition of antioxidants during the derivatization, and eluent selection. Varietal thiols and derivatives were isolated by solid-phase extraction and microex- traction. Calibration was performed with standard addition combined with stable isotope dilution analysis. The developed methods were successfully used for the quantification of varietal thiols by gas chromatography–mass spectrometry with tandem mass spectrometry. Detection with a sulfur chemiluminescence detector, which was also performed, suffered from unsatisfactory sensitivity and higher standard deviations.

NMR is a swift and highly reproducible spectrometric technique that makes it possible to obtain spectra containing a lot of information about the sample analyzed. This approach helps major components be described in complex mixtures such as wine in just one analysis. Analysis of wine metabolites is very often used to understand the impact of geographical origin or variety on wine quality. NMR is often used for tracing the geographical origin of wine. Research on NMR metabolic effects of geographical origin is of great importance as the high added value of wines results from compliance with state legislation on the protected denomination of origin (PDO) and protected geographical indication (PGI) for the administration of the appellation of wines. A review of NMR with emphasis on SNIF-NMR in the analysis of wine authenticity is given. SNIF-NMR remains a method of choice for the detection of wine chaptalization as it is the only approach which provides position-specific information on the origin of sugar in wine. However, the sample preparation step, which lacks major improvements since its conception, is strenuous and expensive, and suffers from drawbacks in terms of low sample throughput. Mainstream 1D and 2D NMR experiments provide a fast and affordable way to authenticate wine based on the geographical origin, vintage, and variety discrimination, and include a simple and non-destructive sample preparation step. With this approach, spectral data processing often represents a crucial step of the analysis. With properly performed NMR experiments good to excellent differentiation of wines from different vintages, regions, and varieties was achieved recently.

Izbor kvasca za proizvodnju žitnog destilata može značajno utjecati na randman i koncentraciju etanola te konačnu kvalitetu proizvoda. Cilj rada bio je ispitati utjecaj dvije različite vrste kvasaca iz roda Saccharomyces na kvalitetu destilata dobivenog dvostrukom destilacijom fermentirane ječmene sladovine na jednostavnom destilacijskom uređaju. Korištena su dva kvasca, Saccharomyces cerevisiae komercijalnog naziva FERMOALE AY4, te kvasac Saccharomyces cerevisiae (ex. bayanus) komercijalnog naziva EC1118. Kemijskom analizom utvrđeno je kako je primjenom kvasca AY4 postignuta bolja iskoristivost šećera iz ječmene sladovine (3 % više etanola) i niža titracijska kiselost destilata. Plinskom kromatografijom utvrđene su koncentracije acetaldehida u oba uzorka iznad uobičajenih, pa je u uzorku destilata dobivenog korištenjem kvasca AY4 determinirano 274 mg L-1 a.a., a u uzorku dobivenom sa kvascem EC1118, 356 mg L-1 a.a. Nadalje, koncentracije viših alkohola u oba su uzorka bile iznad uobičajenih. U uzorku destilata AY4 determinirano je 2179 mg L-1 a.a, dok uzorak destilata EC1118 zbog determiniranih 3602 mg L-1 a.a. ukupnih viših alkohola ulazi u kategoriju destilata niže kvalitete. Uzorak destilata EC1118 bio je bogatiji etil acetatom, dok je uzorak destilata AY4 imao više koncentracije ostalih estera što je rezultiralo kompleksnijom aromom i punijim okusom destilata AY4., The choice of yeast in cereal spirit production can greatly affect ethanol yield, as well as final product quality. The aim of this study was to evaluate the effect of two different yeast on the quality of spirit produced by double distilling a fermented cereal wash on a simple still. Two yeasts were used, Saccharomyces cerevisiae FERMOALE AY4, and Saccharomyces cerevisiae (ex. bayanus) EC1118. Chemical analysis proved that yeast AY4, as expected, has a better ethanol yield (3 % more ethanol), lower titratable acidity, while ethyl acetate concentrations were slightly higher in sample EC1118. By gas chromatography analysis higher acetaldehyde concentrations than usual was identified in samples, in sample AY4 274 mg L-1 a.a., and 356 mg L-1 a.a. in sample EC1118 was determinated. Furthermore, larger amounts of higher alcohols were produced in both samples, sample AY4 contained 2179 mg L-1 a.a. while sample EC1118 with 3602 mg L-1 a.a. total higher alcohols enter the lesser quality spirit rank. While sample EC1118 was richer with ethyl acetate, sample AY4 had higher concentrations of other esters which made sample AY4 a distillate with more complex aroma and fuller flavour. Future experiments could yield interesting results if the fermentation conditions would match those in a distillery.

Influence of two apple cultivars (cvs. Cripps Pink and Idared) and two commercial strains of Saccha- romyces bayanus (Lalvin EC1118, Fermol Blanc) on the chemical composition and sensory characteristics of apple wines was tested. Chemical parameters (alcohol, sugar-free extract, reducing sugars, titratable and volatile acidity) of the analyzed wines were strongly affected by apple variety. Ash and sugar-free extracts in Cripps Pink wines were significantly higher than Idared wines. Polyphenols and main organic acids were determined in apple juice and wines. Chlorogenic acid was the most abundant polyphe- nolic compound with the significantly higher concentra- tions detected for Idared wines. Total phenolic acids, as well as total flavan- 3-ols content, were also higher for wines made from Idared variety where fermentation was conducted with Fermol blanc yeast. Among organic acids significantly higher succinic acid content was determined in wines where Fermol Blanc yeast was used while Lalvine EC1118, irrespective of apple variety, significantly influ- enced the concentration of lactic acid. Sensory evaluation showed the pronounced influence of variety but also the yeast used, singling out Idared cultivar and Fermol Blanc yeast achieving the best overall quality results.

Merlot and Traminer (Vitis vinifera L.) grapes were subjected to gamma irradiation at the panoramic 60Co source at four doses (670, 1300, 2000, 2700 Gy) and wines were produced from the irradiated grapes. HPLC analysis of musts have shown a negative impact of irradiation on the amino acids content. However, Merlot wines produced from irradiated grapes demonstrated better extraction of the coloring matter. The concentrations of anthocyanins increased with the increasing absorbed irradiation dose, while flavonols and flavanols were not affected by irradiation. Irradiation with doses up to 2000 Gy increased concentrations of fruity-floral aroma compounds, especially monoterpens and C13 norisoprenoids in wines, while a maximal dose of 2700 Gy expressed more the toasty and caramel notes due to higher concentrations of furfural and furfuryl alcohols. Results obtained suggest that ionizing irradiation might be a suitable method for grape treatment since better chemical properties in wine could be achieved.