Wine Faults: State of Knowledge in Reductive Aromas, Oxidation and Atypical Aging, Prevention, and Correction Methods

The review summarizes the latest scientific findings and recommendations for the prevention of three very common wine faults of non-microbial origin. The first group, presented by the reductive aromas, is caused mainly by excessive H2S and other volatile sulfur compounds with a negative impact on wine quality. The most efficient prevention of undesirable reductive aromas in wine lies in creating optimal conditions for yeast and controlling the chemistry of sulfur compounds, and the pros and cons of correction methods are discussed. The second is browning which is associated especially with the enzymatic and non-enzymatic reaction of polyphenols and the prevention of this fault is connected with decreasing the polyphenol content in must, lowering oxygen access during handling, the use of antioxidants, and correction stands for the use of fining agents. The third fault, atypical aging, mostly occurs in the agrotechnics of the entire green land cover in the vineyard and the associated stress from lack of nutrients and moisture. Typical fox tones, naphthalene, or wet towel off-odors, especially in white wines are possible to prevent by proper moisture and grassland cover and alternating greenery combined with harmonious nutrition, while the correction is possible only partially with an application of fresh yeast. With the current knowledge, the mistakes in wines of non-microbial origin can be reliably prevented. Prevention is essential because corrective solutions for the faults are difficult and never perfect

The effect of UV-C irradiation on grape juice turbidity, sensoric properties and microbial count

In this work, we investigated the effect of UV-C radiation (254 nm) on turbidity, microbial count and sensoric properties of the grape juices treated or not treated with sulphur dioxide. The UV-C radiation is considered to be germicidal against microorganisms. This technology is routinely used to treat drinking water. Application of this method for the purpose of treating the wine was tested in few studies. These studies have shown a positive effect on the inactivation of microorganisms, but they not dealt in detail with the sensory properties of grape juice after the treatment. The main idea of using this method appears to eliminate the sulphur dioxide from wine making technology. There are people who have a genuine allergy to sulfites, and these allergies are often linked with asthma. These people have an rapid onset of symptoms when drinking liquids like wine treated with sulphur dioxide. In our work we have found that the application of this method of treating the grape juice is problematic. Intensity of UV-C radiation increases the turbidity of grape juices. This effect was observed in all grape juices with or without addition of sulphur dioxide and also in clarified or not clarified grape juices. We found that UV-C radiation negatively affect the sensory properties of grape juices. This effect was more pronounced in grape juices treated with SO2. The smell and taste were significantly negatively changed. Exposure of grape juice treated with sulphur dioxide to UV-C radiation can probably lead to arising the sulphur compounds, which affects the smell and taste of grape juices. Also, it is very likely that the negative change in taste and smell may affect the quality of produced wines. For this purpose, we do not recommend to use UV-C treatment for the grape juice treatment. It will be interesting to conduct a detailed analysis of the grape juices composition before and after UV-C radiation treatment

Composition of Ewe’s Lump cheese during the production season

AbstractNative sheep breeds provide milk, the raw material rich in nutrients for traditional cheese products, in selected cases labelled with the logo of the Traditional Specialty of the European Union. The study aimed to find out whether seasonal or other factors may significantly affect the composition of traditional Ewe’s lump cheese (“Ovčí hrudkový syr”) manufactured on a farm in the western region of Slovakia. For this purpose, 46 samples of fresh Ewe’s lump cheeses across the season of production undergo analysis following ISO standards focused on determining total fat, dry matter, protein, total casein, and ash. The mean values of the content of individual analytes were as follows: fat 28.60 g 100 g−1, dry matter 51.10%, protein 18.33 g 100 g−1, lactose 2.00 g 100 g−1, ash 2.16 g 100 g−1, casein 17.88 g 100 g−1. Based on statistical evaluation of the results, six significant differences have been found, namely: fat (.01), protein (.005), lactose (.005), dry matter (.05), ash (.001) and casein (.001). Considering all the evaluated aspects of such a product, the Traditional Ewe’s lump cheese presents relatively stable products in the content matter over the season

Fatty acid profile of traditional Slovak ewe’s and cow’s lump cheese

ABSTRACTThe main goal of the research was to find out how the profile and content of individual fatty acids changes in Slovak ewe and cow’s lump cheeses (TSG – Traditional Specialty Guaranteed by European Union). Local farmer produced the cheese. We have analyzed 94 samples of cheeses produced during the production season by the GC/FID method. Fatty acids were found in various concentrations. The following fatty acids were present in the highest concentrations in Ewe’s lump cheese: palmitic acid C16:0 (25.67–35.59 g/100 g), oleic acid C18:1 (n-9) (16.26–25.92 g 100 g−1), myristic acid C14:0 (10.15–14.41 g 100 g−1) and and stearic acid C18:0 (7.23–10.95 g 100 g−1); in Cow’s lump cheese palmitic acid C16:0 (29.46–36.94 g/100 g), oleic acid C18:1 (n-9) (18.93–26.54 g 100 g−1), myristic acid C14:0 (10.07–13.26 g 100 g−1 and stearic acid C18:0 (8.13–10.44 g 100 g−1). Significant (p < .005) changes in individual fatty acid concentrations was found over the production season for most fatty acids. Small farmers can learn the technological process of producing TSG products, but it is important to consider particular seasonal changes in the quantity of fat and fatty acids. From a nutritional perspective, high vaccenic acid concentrations are advantageous, whereas high saturated myristic and palmitic acid concentrations are dubious. The results of this research can be used to supplement the national specification of the TSG Slovak traditional Ewe’s lump cheese (Ovčí hrudkový syr – salašnícky)

Development of PSMA-1007-Related Series of 18 F-Labeled Glu-Ureido-Type PSMA Inhibitors

In recent years, a number of drugs targeting the prostate-specific membrane antigen (PSMA) have become important tools in the diagnosis and treatment of prostate cancer. In the present work, we report on the synthesis and preclinical evaluation of a series of $^{18}$F-labeled PSMA ligands for diagnostic application based on the theragnostic ligand PSMA-617. By applying modifications to the linker structure, insight into the structure–activity relationship could be gained, highlighting the importance of hydrophilicity and stereoselectivity on interaction with PSMA and hence the biodistribution. Selected compounds were co-crystallized with the PSMA protein and analyzed by X-rays with mixed results. Among these, PSMA-1007 (compound 5) showed the best interaction with the PSMA protein. The respective radiotracer [$^{18}$F]PSMA-1007 was translated into the clinic and is, in the meantime, subject of advanced clinical trials

Development of PSMA 1007 Related Series of F 18 Labeled Glu Ureido Type PSMA Inhibitors

In recent years, a number of drugs targeting the prostate-specific membrane antigen (PSMA) have become important tools in the diagnosis and treatment of prostate cancer. In the present work, we report on the synthesis and preclinical evaluation of a series of $^{18}$F-labeled PSMA ligands for diagnostic application based on the theragnostic ligand PSMA-617. By applying modifications to the linker structure, insight into the structure–activity relationship could be gained, highlighting the importance of hydrophilicity and stereoselectivity on interaction with PSMA and hence the biodistribution. Selected compounds were co-crystallized with the PSMA protein and analyzed by X-rays with mixed results. Among these, PSMA-1007 (compound 5) showed the best interaction with the PSMA protein. The respective radiotracer [$^{18}$F]PSMA-1007 was translated into the clinic and is, in the meantime, subject of advanced clinical trials