The content of fat in carp (Cyprinus carpio) tissue was evaluated throughout one year. The following tissues were evaluated: skeletal muscle, soft roe, hard roe, fat tissue, and hepatopancreas. Respective fatty acids were determined using gas liquid chromatography (GLC). The highest content of valuable polyunsaturated acids, like eicosahexaenoic acid, was found in soft roe and in skeletal muscle during summer, in hepatopancreas during spring, in hard roe during fall. The content of eicosahexaenoic acid in hard roe remains high in all seasons except summer. Saturated fatty acids like palmitic acid and stearic acid do not fluctuate very much throughout the year. The maximum concentration of oleic acid was found in summer. Differences in fatty acid concentration among different carp tissues depended on the living style, but their variation in the same tissue within the year depended on the main fodder of fish.

The relation between nutrition and health has been unequivocally established. Wrong eating habits and losses of nutritional factors during technological processing, storage, and culinary treatments can lead to the diet deficient in some nutritional factors. Barley green matter was analysed for the contents of vitamin C, total polyphenols, phenolic compounds, proteins, amino acids, and saccharides; the activity of catalase was also determined. The contents of vitamin C, total polyphenols, and ferulic acid decreased with the age of barley plants. The influence of the variety has not been proved unequivocally. The contents of vitamin C between 0.107-6.357 g/kg DM, of total polyphenols between 17.167-35.559 g/kg DM, and of ferulic acid between 0-5.916 g/kg DM were found. Catalase activity amounted to 4.5-29.7 TSU. The monosaccharide profile showed high contents of glucose (15.40-88.40 g/kg DM) and fructose (37.60-81.40 g/kg DM) which decreased with the plant growth. The contents of saccharose and galactose were low, ranging between 0-7.70 g/kg DM and 3.70-5.30 g/kg DM, respectively. The relations between their contents and the growth phase were insignificant. The total amino acid content decreased with the plant age. High contents of aspartic (15.232-28.682 g/kg DM) and glutamic acids (16.694-35.526 g/kg DM), as well as minimal contents of sulphur amino acids, especially methionin (2.586-5.03 g per kg DM), could be noted. The highest catalase activity was found in the early growth phase (18.5-35.1 TSU), being higher in all samples grown at the location Kroměříž. The yield of juice pressed out from frozen green matter amounted to 68%. The pressed out juice was preserved by fluid drying, freeze drying, and freezing. In respect to folates and total polyphenols contents and the antioxidant activity, freezing appears the most suitable procedure for preserving.

We evaluated the nutritional factors of underutilized cereals (spelt, emmer, einkorn, millet, foxtail millet, semiperennial rye, naked oat, and naked barley) and buckwheat. The basic food components as well as minor nutrients were determined. The analyses included dry matter, ash, protein, dietary fiber, fat, fatty acids, amino acids, minerals, and lipophilic and hydrophilic vitamins. Rutin was also determined in buckwheat. We hope to offer new recipes for the healthy food production and for special dietary use (diabetes, celiac disease, phenylketonuria diet, etc.). Use of the germinated seeds is also suggested. The examples of some healthy food products in the Czech Republic are mentioned.

Onion skin is a waste produced in thousands of tons annually in the European Union. It is a rich natural source of flavonoids and its water extracts (as an environmentally friendly solvent) could be used as an antioxidant material for meat products. Therefore, antioxidant properties of onion skin water extracts (OSWEs) were tested on cooked pork patties. Pork patties were divided into five treatments: control (no antioxidant), 10 and 20% (w/w) of yellow OSWE, and 10 and 20% (w/w) of red OSWE. Antioxidant activity, total polyphenols, thiobarbituric acid reactive substances (TBARS), and sensory analysis were assessed. Patties with added antioxidants showed significantly (P < 0.05) higher antioxidant activity and total polyphenol content. Samples with OSWEs, after 5-day storage (5°C), had significantly (P < 0.05) lower TBARS values compared to control. Two main phenolic compounds were identified in OSWEs by liquid chromatography – mass spectrometry using electrospray ionisation in negative mode: quercetin (m/z 301) and quercetin monoglucoside (m/z 463). OSWEs demonstrated the potential to be used as a source of natural antioxidants with strong antioxidant activity in meat products.

This work aimed to determine if it was possible to eliminate or reduce the content of the Api g1 allergen in celery juice by oxidation, utilising its natural polyphenol oxidase (PPO) content. We attempted to determine a possible relationship between the enzymatic browning of celery juice and the reactivity of the Api g1 allergen. Pressed celery juice was stirred, and samples for the colour measurement and allergenicity, determined using the Western Blot (WB) method, were collected at pre-defined times. Oxidation failed to eliminate the allergenicity of pure celery juice. Further trials were focused on celery allergen elimination in apple-celery juices mixtures in ratios of 3:1, 5:1, and 7:1. We selected the 5:1 ratio as the most acceptable from the sensory perspective, and monitored its allergenicity using the WB method, basophil activation test, and skin prick testing. The WB test showed that oxidation, caused by stirring for 120 min, reduced the allergenicity of the mixture. However, the basophil activation test showed no reduction in the allergic response to the oxidised juice mixture. Skin testing showed that the oxidised juice mixture stirred for 120 min exhibited a significantly lower reaction than the juice mixture stirred for 60 min or celery and apple juice stabilised with ascorbic acid. Due to the contradictory results in different tests, the method cannot be declared successful or safe, even for mixtures of apple-celery juices.