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 microextraction. 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. For the first time, the concentration of varietal thiols in samples of Croatian Sauvignon Blanc wine was determined, with values ranging from 6 to 135 ng L
−1
.
High-added value biological compounds (BACs) from herbal and plant sources, such as essential oils (EO), antioxidants and volatile compounds, often exhibit remarkable features, ranging from nutritive ...and medicinal properties, as well as antimicrobial and antioxidant activities, which can be exploited in the production of functional foods. However, most BACs exhibit low water solubility, strong off-flavors/odors, and are generally unstable and easily degraded under common processing and storage conditions. Encapsulation is a technology that enables the delivery in food systems, the protection, as well as the controlled and targeted release of BACs.
The aim of this review is to summarize the most important information for encapsulation of natural extracts using unconventional technologies.
Encapsulation is an excellent choice to stabilize BACs, and in particular EOs, and mask their strong flavors and odors. In particular, spray drying is one of the most economic and common encapsulation technologies. However, the challenges of reducing the operating costs, of developing high-throughput processes, of minimizing the use of organic solvents, and of increasing the level of functionality of the encapsulation systems are driving the research towards the implementation of innovative strategies and non-conventional methods, which incorporate the concepts of Green Food Processing.
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•Biological compounds from herbal and plant sources have remarkable features.•Encapsulation is a technology that enables their delivery in food systems.•Encapsulation of natural extracts can be achieved by unconventional technologies.
Rosemary (
L.) is a Mediterranean medicinal and aromatic plant widely used due to valuable bioactive compounds (BACs) and aromas. The aim of the study was to evaluate the extraction of intracellular ...compounds from rosemary combining experimental procedure by means of high voltage electrical discharge (HVED), with a theoretical approach using two computational simulation methods: conductor-like screening model for real solvents and Hansen solubility parameters. The optimal HVED parameters were as follows: frequency 100 Hz, pulse width 400 ns, gap between electrodes 15 mm, liquid to solid ratio 50 mL/g, voltage 15 and 20 kV for argon, and 20 and 25 kV for nitrogen gas. Green solvents were used, water and ethanol (25% and 50%). The comparison was done with modified conventional extraction (CE) extracted by magnetic stirring and physicochemical analyses of obtained extracts were done. Results showed that HVED extracts in average 2.13-times higher total phenol content compared to CE. Furthermore, nitrogen, longer treatment time and higher voltage enhanced higher yields in HVED extraction. HVED was confirmed to have a high potential for extraction of BACs from rosemary. The computational stimulation methods were confirmed by experimental study, ethanol had higher potential of solubility of BACs and aromas from rosemary compared to water.
This review presents a critical analysis of food-grade delivery systems, which are suitable for the delivery of essential oils (EOs) for food applications. In particular, the main colloidal systems, ...investigated in vitro for the encapsulation of essential oils, such as nanoemulsions, solid lipid nanoparticles, nanostructured lipid carriers, carbohydrate-based carriers, protein-based carriers, liposomes and gelatin, have been described in details, with a special focus on their formulation, the type of oils encapsulated, and the fabrication processes, as well as on the resulting antimicrobial activity with respect to free oils. Currently, among these food-grade colloidal systems, only nanoemulsions, liposomes, and biopolymeric particles have found use in real foods, because of their easily-scalable production processes, loading capability with EOs, as well as cost-effectiveness. The main applications in foods are discussed, with reference to the possible methods of incorporation of encapsulated essential oils in foods, such as direct mixing, washing or infusion, and coating within active biopolymeric matrices. In addition, also the use of encapsulated essential oils in several other fields is presented, such as in organic farming, pest control or luring, as well as in pest-repellent textiles. Finally, the main regulatory issues are discussed.
Celotno besedilo
Dostopno za:
BFBNIB, DOBA, GIS, IJS, IZUM, KILJ, KISLJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
Herein we report a comprehensive study on novel carbonyl- and ethenyl-linked symmetric dimers that combine synthesis, mesomorphic properties and molecular modelling. The study has been focused on the ...impact of geometry imposed by the linkage group on the incidence of the twist-bend nematic (N
TB
) phase. Comparison of the mesomorphic properties of these two series complemented with computational studies of conformational space around the linkage group points molecular curvature and intramolecular torsion plays important role in the appearance of the N
TB
phase and can be regarded as the basic structural requirements for design of new twist-bend nematogen materials.
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.
From 2018 to 2020, an experiment on effects of nitrogen top-dressing was conducted with Burley tobacco on the Zagreb experimental field at the Faculty of Agriculture. The experiment was set up ...according to the RCBD in four replications. Nitrogen was added to the top-dressing in five different variants: 1) control 100% from CAN; 2) 90% from CAN + 10% from microcapsules; 3) 80% from CAN + 20% from microcapsules; 4) 90% from CAN + 10% from microcapsules with chitosan; and 5) 80% from CAN + 20% from microcapsules with chitosan. During vegetation, number of leaves, length and width of the 9th leaf, topping height, and days to flowering were determined. After drying, the yield was determined, and the tobacco was classified into six classes. According to the analysis of variance, significant differences were established for share of I class, width od 9th leaf, topping height days to flowering in 2018, yield, share of VI class in 2019, yield, share of V class, and leaf number in 2020. Significantly, the highest yield had control compared to the variants 80% from CAN + 20% from microcapsules with chitosan in 2019 and the variants 80% from CAN + 20% from microcapsules in 2020. The control had the significantly highest share of I class in 2018. The highest leaf number in 2020 had the control and variant 90% from CAN + 10% from microcapsules with chitosan compared to the variant 80% from CAN + 20% from microcapsules with chitosan. The effect of microencapsulation has not given the expected results.
Natural deep eutectic solvents (NADES) represent a promising group of green solvents employed for the extraction of bioactive compounds from medicinal plants. Due to the wide range of polarities of ...investigated solutes, and an outstanding number of combinations of NADES components, fine tuning and selection by software for modeling and evaluation of thermodynamic properties of solvents and solutes is a necessary step preceding the extraction from real samples. In this study, four hydrophilic NADES were chosen for the prediction of solubility of 19 bioactive compounds from Mediterranean plants, which was performed by COSMO-RS software. NADES structure optimization was performed by pseudocomponent approach and individual constituent approach. Change of hydrogen bond donor components of NADES did not show a significant influence on the solubility of screened solutes. According to both approaches, the investigated systems represent promising solvents for extraction of hydrophilic and moderately lipophilic flavonoids, terpenoids, and phenylpropanoids, while being unsuitable for extraction of the most lipophilic (logkow ≥ 4) natural products and compounds lacking polar functional groups due to the absence of sites participating in hydrogen bond formation.
Utjecaj kvasaca na kvalitetu žitnog destilata Mihaljević Žulj, Marin; Počepan, Ivan; Viskić, Marko ...
Glasnik Zaštite Bilja,
05/2020, Letnik:
43, Številka:
3
Journal Article, Paper
Recenzirano
Odprti dostop
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.
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