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The research is devoted to the issue of processing substandard amber to enable the use of the processing products in food, cosmetics, and pharmaceutical industries. For the first time, comparison was made of the extractive characteristics of amber from the two largest world deposits – the Baltic and Ukrainian. Nine times more dry substances are transferred to the extract from Ukrainian than from Baltic amber, when extracting amber with ethanol under the same conditions. The antioxidant activity of the obtained extracts was determined by ABTS+and DPPH methods. The values of these indicators were higher in the extract of Ukrainian amber and also differed in extracts from different fractions. Analysis of the volatile components composition did not indicate a significant difference between the extracts of different amber, but clear differences were seen between the fractions from which the extract was obtained. The main component, representing more than a half of the volatile components, was o–Cymene. Most of the identified components are characterised by camphor odour. Amber from different places of origin have different extraction characteristics, which was confirmed by the research results.

Potatoes (Solanum tuberosumL.) are an important crop. They are a source of natural phenolic compounds with high biological activity. Stress factors may decrease phenolic concentration and increase concentration of the toxin glycoalkaloid as a result of plant self-protection against stress. The aim of the current study was to evaluate the effect of storage under light on the concentration of biologically active compounds in purple-fleshed potatoes. The purple-fleshed potato variety ‘Blue Congo’ was harvested from test fields of the Institute of Agricultural Resources and Economics in Latvia. Storage under light was performed in a climate chamber ICH110 (Memmert GmbH + Co. KG, Germany) with constant pre-set relative air humidity 85%, temperature +22 °C, and full-spectrum light (Eecoo, 1200 W, LED) intensity of 2000 lux and total time seven days. Total phenolic concentration, antioxidant activity and total glycoalkaloid concentration was measured using spectrophotometry, and moisture was determined according to standard LVS 272:2000. Storage under artificial light of purple-fleshed variety ‘Blue Congo’ potatoes caused decrease of total phenolic concentration and antioxidant activity, no change in moisture level, and increase of total glycoalkaloid concentration.

Moderate consumption of wine is associated with positive health effects. Red wine contains more polyphenolic compounds than white wine, so it is considered healthier. The aim of the study was to determine the concentration of bioactive compounds of red grape and berry wines available for purchase in Latvia. A selection of 15 red grape and berry wines purchased in Latvian supermarkets were analysed. The total phenol concentration was determined using the Folin-Ciocalteuspectrophotometric method with minor modifications. Total flavonoid concentration was determined using the colorimetric flavonoid determination method. Antiradical activity was determined using the DPPH (2,2-diphenyl-1-picrylhydraziyl) reagent and ABTS (2,2-azino-bis(3-ethylbenzothiazoline-6-sulfonate) radical cation determination method. The results show that the analysed red wine samples can be divided into five clusters according to the concentration of total phenols, flavonoids, and antiradical activity. Cluster 1 separately divided Latvian black chokeberry wine, with high total phenol concentration (TPC) and total flavonoid concentration (TFC), high antiradical activity via the DPPH method, and relatively low antiradical activity via ABTS method. Cluster 4 combined red wines with medium TPC, high TFC and high antiradical activity via both DPPH and ABTS methods, and included grape wines from different countries of origin. Cluster 5 combined red wines with high TPC, medium TFC, and medium antiradical activity via both DPPH and ABTS methods.

In the production of fermented cabbage, cell juice of cabbage is released, which is highly saturated in biologically active compounds, but is considered as a by-product. The aim of this study was to evaluate the quality parameters of dehydrated fermented cabbage juice using maltodextrin as a coating agent at various concentrations. In this experiment, fermented cabbage juice was used — spray dried on a horizontal spray-dryer and maltodextrin, in different concentrations (0; 5; 10%). Physical (water activity, solubility, salt content, and moisture), chemical (total phenolic concentration, antiradical activity, and organic and titratable acid concentration) and microbiological (total plate count and lactic acid bacteria) analyses were carried out. The major acids identified were oxalic, quinic, lactic, and acetic acid. Total phenol concentration was influenced by the concentration of maltodextrin used with higher values in the samples with no coating agent. The total viability of microorganisms and lactic acid bacteria (8.9·103– 4.2·104colony forming units (CFU)·g−1) did not reach the probiotic potential according to FAO and WHO. Salt concentration ranged from 8.9% to 14.3%, moisture content was 5.3 % to 7.03%, solubility in water — 81.74% to 82.8%. Horizontal spray drying with maltodextrin as a coating agent proved to be a suitable solution to obtain an innovative product — dehydrated fermented cabbage juice.

During the roasting process, a cascade of chemical reactions occur, from which non-volatile compounds degrade and form new compounds with potential aroma attributes. Considering that the roasting process significantly influences the biologically active compound concentration and some unwanted compound formation, such as acrylamide, it is crucial to understand the roasting process from both positive and negative aspects. The aim of this study was to evaluate the chemical composition changes in different roast level coffee samples from Colombia. The moisture, pH, acrylamide, total phenolic, and flavonoid content, and the volatile compound profile were analysed for coffee samples roasted at three different roast levels (light, medium, dark). The results showed a decrease of total phenolic and flavonoid concentration with increased roast level. Acrylamide concentration reached the highest peak in the medium roasted and the lowest in dark roasted coffee. With increasing roast level, the volatile organic acid concentration decreased, while furan and phenol compound concentration increased in the dark roasted coffee. Dark roasted coffee had the lowest acrylamide and organic acid concentration, and the highest pH in brew, which would be more suitable for coffee consumers with a sensitive stomach.

Freezing is one of the ways to preserve plant products, because it allows inhibiting natural degradation and transformation processes of the bioactive compounds. The aim of this study was to evaluate the effect of freezing on bioactive compounds of horseradish roots and their dynamics in long-term frozen storage. Horseradish roots were frozen at two different conditions (–18±2°C and –40 ± 2 °C) and further stored at –18 ± 2 °C for 12 months. Total phenolic content (TPC), total flavonoid content (TFC), total flavonol content (TFlC), total flavan-3-ol content (TF3C), total phenolic acid content (TPAC), and radical scavenging activity (RedPow, DPPHÿ, ABTSÿ+) were determined spectrophotometrically. Individual phenolic compounds were deremined by liquid chromatography. The dominant individual phenolic compounds were phenolic acids (gallic and sinapic) and flavonoids (kaempferol, luteolin, and rutin). Because of freezing, TPC, TFC, and DPPHÿ as well as RedPow increased in horseradish roots. During storage, the content of analysed bioactive compounds mainly decreased. After 12-month storage, it was not possible to say unambiguously which of the freezing methods turned out to be better in general.

There are approximately 590 million people in the world with swallowing disorders (dysphagia), who need texture-modified foods to ensure nutritional intake on a daily basis. The aim of this research was to create new texture-modified products and to evaluate their bioactive and mineral compound concentration. Nine new products (five desserts and four puree-soups) were developed from plant-based ingredients with addition of a source of protein, canola oil, ascorbic acid, and other ingredients. Obtained samples were vacuum-cooked, sterilised at 115 °C for 5 min and tested for their bioactive compound concentration (total carotene and phenol concentration, and ABTS and DPPH radical scavenging activity), and concentration of seven vitamins and thirteen minerals important in human nutrition. The obtained data showed that bioactive compound concentration varied from sample to sample, which was expected due to the varied ingredients of each product. Mineral compound concentration analysis showed low levels of iodine, molybdenum, and selenium. The vitamin analysis showed traces of vitamin D3and low levels of B group vitamins. Overall, the analysed product composition indicated that the natural background of these products is insufficient for ensuring the human body with all of the necessary vitamins and minerals, and the best solution could be the supplementation of these products with complexes of vitamins and minerals.

The objective of the current study was to analyse the total phenolic concentration (TPC), total flavonoid concentration (TFC), individual phenolic compound concentration and DPPH′ radical scavenging activity of four buckwheat (raw, roasted, white and dark) flour samples obtained from the Latvian market, in comparison to those of wheat flour, which is the most common ingredient in production of cereal products. TPC, TFC, and DPPH′ radical scavenging activity values were determined using spectrophotometric methods. Phenolic compounds were determined based on the high performance liquid chromatographic method (HPLC). All buckwheat flour samples had significantly higher TPC and TFC than wheat flour. The highest TPC (974.74 mg GAE·100 g−1DW) and TFC (495.31 mg CE·100 g−1DW) was found in raw buckwheat flour (p < 0.05). Buckwheat flour samples demonstrated similar DPPH′ radical scavenging activity, which ranged from 21.067 to 22.644 mM TE·100 g−1dry matter, and was significantly higher (p < 0.05) than in wheat flour (0.731 mM TE·100 g−1of dry matter). Dark buckwheat flour contained the highest level of rutin (4.613 mg·100 g−1), whereas raw buckwheat flour displayed the highest level of 3.5-dihydroxybenzoic acid (6.356 mg·100 g−1), sinapic acid (0.947 mg·100 g−1) and epicatechin (2.608 mg·100 g−1).