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Raspberry fruits are a valuable source of bioactive compounds. The study used the modification of the substrate (coconut fibre), consisting of the use of various organic and mineral additives, in the soilless cultivation of raspberries. The additives influenced the biosynthesis of bioactive compounds in the raspberry fruits by modifying the sorption properties and the abundance of the substrate. The influence of the additives on the content of polyphenols was determined as well as their profile (UPLC-MS), antioxidant potential (ABTS), vitamin C content, and the activity of selected enzymes that are markers of stress and resistance to abiotic factors. In the study, a significant effect of these additives was observed on the biosynthesis of polyphenols in raspberry fruit. The highest increase in the content of these compounds in relation to the control sample (substrate-100% coconut fibre), namely 37.7%, was recorded in the case of fruit produced on coconut substrate enriched with sheep wool. These fruits were also characterised by a significantly different profile of these compounds. These changes were caused by readily available ammonium nitrogen and free amino acids in the decomposition of proteins contained in the sheep wool. This was confirmed by the recorded content of chlorophyll SPAD in the plant leaves and the activity of selected enzymes, which proves a low level of stress and good condition of the plants.

Research into the suitability of domestic raw materials, including, for example, new wheat cultivars and fruit additives for the production of flavoured beers, is increasingly being undertaken by minibreweries and craft breweries. The fruits of the Saskatoon berry are an important source of bioactive compounds, mainly polyphenols, but also macro- and microelements. The fruits of two Canadian cultivars of this species, 'Honeywood' and 'Thiessen', were used in this study. Physicochemical analysis showed that wheat beers with the addition of non-ozonated fruit were characterised by a higher ethanol content by 7.73% on average. On the other hand, enrichment of the beer product with fruit pulp obtained from the cv. 'Thiessen' had a positive effect on the degree of real attenuation and the polyphenol profile. Sensory evaluation of the beer product showed that wheat beers with the addition of 'Honeywood' fruit were characterised by the most balanced taste and aroma. On the basis of the conducted research, it can be concluded that fruits of both cvs. 'Honeywood' and 'Thiessen' can be used in the production of wheat beers, but the fermentation process has to be modified in order to obtain a higher yield of the fruit beer product.

Elderflowers are a well-known source of bioactive compounds. The amount of isolated bioactive compounds may be increased by applying various abiotic and biotic factors. Gaseous ozone (10 and 100 ppm) was used in the process of preparing flowers. Next, the flowers were treated with sugar syrup to extract bioactive compounds. It was shown that this treatment, including the influence of extraction temperature, significantly affects the contents of polyphenols (liquid chromatography–mass spectrometry (LC–MS) methods) and vitamin C, as well as the antioxidant potential (cupric reducing antioxidant capacity (CUPRAC method)), the profile of volatile substances (head space–solid-phase microextraction (HS–SPME methods)) and the colour of the syrup (Commission Internationale de l’Eclairage (CIE) L*a*b* methods). The findings show that an increased dose of ozone and higher extraction temperature applied in the process of syrup production resulted in higher contents and different compositions of bioactive compounds. The highest contents of bioactive compounds were identified in syrup obtained from raw material treated with ozone for 15 min (concentration = 10 ppm) and extraction with sugar syrup at a temperature of 60 °C.

This study investigates the effects of various drying methods applied to leaves of Cistus creticus L. on the contents of polyphenols and the composition of the volatile fraction. The following four drying methods were used: convection drying at a temperature of 40 °C (CD 40 °C), 50 °C (CD 50 °C), and 60 °C (CD 60 °C); vacuum-microwave (VMD 240 W); combined drying, involving convection pre-drying (50 °C) and vacuum-microwave (240 W) finish drying (CPD-VMFD) as well as freeze-drying (FD). Polyphenols in the dried leaves were determined using chromatography-photodiode detector-quadrupole/time of flight-mass spectrometry (UPLC-PDA-Q/TOF-MS). The contents of odoriferous substances in the dry material were determined by means of head space-solid phase microextraction (HS-SPME) with the use of a gas chromatograph (GC). Thirty-seven polyphenol components including 21 flavonols, eight flavan-3-ols, and eight hydrolyzed tannins in dry Pink Rock Rose material were found for the first time. The highest contents of polyphenols, totaling 2.8 g 100 g−1 dry matter (d.m.), were found in the samples subjected to the CPD/VMFD drying method. Pink Rock Rose subjected to this drying method was characterized by large quantities of odoriferous compounds, mainly eugenol, thymol, and carvacrol, which contribute to its antiseptic properties. By using CPD/VMFD methods, it is possible to obtain fine quality dry material from the leaves of C. creticus.