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Beetroot is a vegetable known since antiquity, valued due to its high pro-health potential resulting from the high content of betalaine pigments, mainly betanin. Due to the allergenic nature of this compound, there may be some of the restrictions concerning red beetroots consumption. This study analysed the physicochemical characteristics of a new white beetroot cultivar 'Śnieżna Kula' ('Snowball'), which can become an alternative to red beetroot. The effects of the size and particular parts of the roots were assessed on betalain pigment, reducing sugar, total sugar, phenolic compounds, nitrate (III) and nitrate (V) contents, and on the antioxidant capacity (expressed as a FRAP and ABTS value). The mass of the beetroots of the 'Śnieżna Kula' cultivar varied and ranged from 279 to 1118 g. The analysed beetroot is devoid of red betalain pigments. The total sugar content was the highest for group B (401–600 g) with an average of 33.5 mg kg−1 FW. The roots with a less weight, i.e. those of groups A contained their greater amount phenolic compounds and chlorogenic acid (415 mg kg−1 FW i 279 mg kg−1 FW, respectively). A the same time, less roots contained more nitrates (V), ranging from 3 301 to 3 534 mg kg−1 FW. The inner parts of the root contained more nitrates (III) and (V), while the outer parts of the roots were richer in polyphenols and chlorogenic acid. The antioxidant capacity was correlated with polyphenol and chlorogenic acid contents. The roots for group A (<400 g) the bottom under leaf part and the bottom under leaf part proven antioxidant capacity respectively 17.5; 16.3 mmol Fe2+ kg−1 FW (FRAP) and 8.50; 8.40 mmol Trolox kg−1 (ABTS). [ABSTRACT FROM AUTHOR]

The aim of this study was to determine the effects of mechanical damage on both the contents of dry matter and chlorogenic acid and the degree of blackspot for five cultivars of potatoes of various earliness groups. The study was conducted immediately after the harvest as well as after two, four and six months of storage under constant conditions (air temperature +4 °C and RH 95%). Mechanical damage leads to a greater accumulation of chlorogenic acid and increases the tubers' susceptibility to blackening, irrespective of the earliness group. The duration of storage significantly determines the dry matter content of chlorogenic acid and the susceptibility to blackening of raw tuber flesh to the greatest extent for cultivars of the medium-early group. A significant (P < 0.01) correlation was demonstrated between the dry matter and chlorogenic acid contents and the degree of blackspot, which was higher on damaged tubers. [ABSTRACT FROM AUTHOR]

Plums are a popular fruit whose large quantities are subjected to processing, which contributes to changes in the physicochemical parameters, and the magnitude of these changes is determined by the technology applied. The study aimed to analyse the bioactive compound content and the antioxidant capacity of plums of the Bluefree, Stanley and Sweet Common Prune (Węgierka Zwykła) varieties, depending on the drying and extraction processes applied. Significant differences in the bioactive compound content and the antioxidant capacity were found between the varieties under study. The convection drying process resulted in the greatest significant decrease in both the anthocyanin pigment content (by an average of 82%) and the total polyphenol content (by an average of 41%). The average losses of phenolic acids reached 34%, and the greatest decrease was noted for chlorogenic acid (an average of 69%). As regards flavan-3-ols and flavonols, the drying processes caused their losses by an average of 56%. The vacuum drying and lyophilisation processes applied were softer for the tested bioactive compounds. Moreover, these processes reduced the ABTS and FRAP antioxidant capacity. The ultrasound- and microwave-assisted extraction increased the total anthocyanin content by an average of 29%. These methods yielded significantly greater amounts of all four determined anthocyanins in the tested fruit. The results show that the search for a safe, inexpensive raw material drying method is still a current research issue. • The vacuum drying and lyophilisation processes applied are gentle on bioactive compounds. • The convection drying process resulted decrease the total polyphenol content. • The ultrasound and microwave-assisted extraction increased the total anthocyanin content. [ABSTRACT FROM AUTHOR]

The application of biostimulants to prevent stress-related losses and increase productivity is becoming an increasingly common practice. A study was carried out to determine the effect of the type and methods of biostimulant application and long-term storage on the content of antioxidant compounds determining the processes of the enzymatic browning of carrot roots. The natural seaweed biostimulant Kelpak and synthetic Asahi were applied as part of the study. A quality assessment of carrot roots was carried out directly after harvest and after six months of storage in air at a temperature of 1 °C and a relative humidity of 95%. A single application of Kelpak seaweed extract in the four-leaf phase (2 or 3 dm3 ha−1) proved to be the most effective for reducing oxidative darkening processes (by 33.5%). The oxidative potential was most strongly dependent on the anthocyanin (r = −0.477) and chlorogenic acid (r = −0.474) contents. The concentration of polyphenols (r = 0.836; r = 0.719) and flavonoids (r = 0.671; r = 0.729) had the greatest effect on the antioxidant capacity (FRAP and ABTS respectively). It was observed that pectin, polyphenol, chlorogenic acid, flavonoid and anthocyanin concentrations tended to increase after a single application of Kelpak in a dose of 2 dm3 ha−1. A long-term storage period had a stronger effect on the increase in the oxidation potential than on the antioxidant capacity FRAP value. [ABSTRACT FROM AUTHOR]