Mechanically separated fish meat (MSFM) can be used for the manufacturing of ready-to-eat products, such as sausages; however, it is highly perishable. Several plant by-products, including onion peel, which is rich in polyphenol antioxidants, can be added to food to extend shelf life. This study investigated the effects of the addition of onion peel powder (OPP) to sausage made from MSFM. Sausages were divided into four groups with different amounts of added OPP: 0% (control), 1%, 2%, and 3%. Cooked sausages were stored for 28 days at 5 °C. Samples were analyzed for thiobarbituric acid reactive substances, antioxidant activity, total polyphenol content, pH, and organoleptic properties. The addition of OPP significantly increased antioxidant activity and total polyphenol content and decreased pH, indicating acidic nature of OPP. Polyphenols from OPP effectively suppressed lipid oxidation. A 1–2% addition of OPP enhanced sensory properties. After the 28-day storage, the control samples received the lowest sensory score, due to the presence of a strong fishy odor, which was not present in samples with OPP. HPLC–MS/MS analysis revealed that quercetin is the most dominant compound in OPP. Overall, the results indicate that the addition of OPP in amounts of 1–2% can extend shelf life, without the deterioration of sensory properties.

Black garlic (BG) is a product originating from fresh garlic (FG) and substantially differs in many aspects from FG due to the process called ageing. During this thermal process, the health-promoting properties of FG are enhanced, and the sensory traits are altered. However, very little is known about how the physicochemical properties of different FG varieties affect these properties of BG. Thus, the aim of this study was to investigate the influence of seven FG varieties subjected to the thermal process on the physicochemical parameters of BG. To prepare the BG samples, a fifteen-day ageing process involving a temperature gradient ranging from 30 to 82 °C was used. It was found that the antioxidant activity, the total polyphenol content, and the total soluble solids increased during ageing, while the pH level, moisture content, and lightness decreased in all the garlic varieties. The varieties of garlic differed in the studied traits significantly, both before (FG) and after ageing (BG). In the sensory analysis, significant differences between the BG varieties were observed only in the pleasantness of texture, while the remaining sensory descriptors (pleasantness of color, odor, taste and intensity of the garlic aroma, and overall acceptability) were not affected by variety. The correlations suggest that most of the FG’s studied parameters in this study do not correlate with the properties of BG and cannot be used for the prediction of the quality of BG. Additionally, HPLC-MS/MS analysis revealed substantial changes in the composition of low molecular compounds.

Powders prepared from freeze-dried roots of six beetroot ( Beta vulgaris L.) cultivars with red (cv. D'Egypte, Karkulka, Betina, Alexis), yellow (cv. Burpee's Golden) or red-white (cv. Chioggia) colour of root flesh were evaluated before and after boiling treatment (20 min, 100°C). Water and...

Radioprotective agents derived from natural food sources represent promising candidates for reducing the harmful effects of ionizing radiation and supporting healthy aging. In this study, we investigated the effects of selected micronized bioactive compounds and their mixes on DNA damage response pathways in human retinal epithelial cells (hTERT-RPE1). Individual compounds and their combinations were applied to cultured cells, and the expression of IER5, a radiation-inducible gene associated with DNA repair and cell survival, was evaluated, showing that most potent compound to be lycopene and quercetin. Thus, in the next step, commonly consumed foods available on the Czech market rich in moth—tomato and garlic—were analyzed for their antioxidant capacity. The results revealed marked variability in antioxidant potential among food sources, with specific cultivars exhibiting significantly higher values. Importantly, experimental mixtures of pure and micronized compounds demonstrated distinct and sometimes opposing effects on IER5 expression. These findings indicate that the radioprotective activity of dietary antioxidants depends not only on the properties of individual compounds but also on their specific combinations. Our study provides evidence that phytochemicals such as quercetin, lycopene, but also partially resveratrol and curcumin can modulate DNA-repair-associated pathways and underscores their potential as combinatory agents in strategies aimed at promoting genomic stability and potentially healthy aging.