We examined the effect of two different technological processes for wine production on qualitative parameters of wine. We used the reductive method, which is currently considered to be the conventional method, and a targeted must oxidation method. We evaluated the basic physicochemical parameters and sensory attributes of wine as well as the content of phenolic substances in wine, which are responsible for the oxidation processes. The vegetable materials used were the grape varieties, Welschriesling, Chardonnay, and Rheinriesling. The content of phenolic substances was determined by HPLC (high-performance liquid chromatography), and the basic analytical parameters of wine were determined by FT-IR (Fourier Transform Infrared Spectroscopy) spectrometry. The sensory analysis was evaluated according to the International Union of Oenologists. For each of the wines examined, the total content of phenolic substances decreased after the targeted oxidation method was applied. For the Welschriesling variety produced by the reduction method, the total content of the 19 monitored phenolic substances in the year 2015 was 88.37 mg·L−1, and for the wine produced by target oxygenation, it was 68.63 mg·L−1. This represents a decrease of 21.5%. In the year 2016, the decrease was 20.91%. By reducing the content of phenolic substances, the oxidation processes in wines are eliminated after bottling. Thus, there is less need for sulphating wines with a reduced content of phenols.

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.

In the study regarding with tomatoes, the impact of extremely low frequency electromagnetic fields on seed germination of tomato (Solanum lycopersicum L.) after treatment before sowing, as well as the growth following electromagnetic stimulation of young plants at a time before planting in the field, and fruittraits was investigated. In the experiments conducted in two consecutive years (2012 and 2013), we followed the time of seed germination of tomato variety "Pavlina", plant growth and the fruitsize. Magnetization of seeds and young plants was carried out in laboratory conditions, and plant growth and fruits were followed in field conditions where plants were grown on experimental plots (25.0 m 2 ). The plants were grown in accordance with the standards of agricultural practice for tomato. At the generative phase, fruits were collected at regular intervals, and their number and weight were evaluated. Low frequency electromagnetic fields acting at the three inductance levels (20, 40 and 60 mT) and exposure of 20 minutes a day with frequency of 50 Hz, significantly influenced the germination, plant growth and fruitsize of the studied tomato variety.

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The influence of the technological processes of grape processing on the content of hydroxycinnamic acids and volatile phenolic substances in wine was studied. The method of targeted oxygenation was applied in grape processing technology of the Welschriesling and Chardonnay grape varieties. The content of volatile phenolic substances was determined by gas chromatography, the content of hydroxycinnamic acids by liquid chromatography, and the basic analytical parameters of the wine by FTIR spectrometry. The method of targeted must oxygenation had a statistically significant effect on the content of hydroxycinnamic acids and volatile phenolics in the wine. In all three monitored years (2015–2017), the content of 4-vinylphenol and 4-vinylguajacol in the wine significantly decreased. A significant dependence between the content of hydroxycinnamic acids and volatile phenolics was found. The experiment showed that a 1% increase in the content of hydroxycinnamic acids in the Chardonnay variety could result in an average increase in the content of monitored volatile phenolics by 3.6% (3 years’ data). Naturally reducing the content of hydroxycinnamic acids, with the application of technological processes, eliminated the oxidative processes during wine maturation. Sensory undesirable volatile phenolic substances were consequently formed in lower quantities, and there was no negative impact on the favourable sensory properties of wine. It was not necessary to use the polyvinylpolypyrrolidone adsorbents.