Mikołaj Pawlik

In the present study, pectin films with antioxidant activity were obtained in response to the increasing demand for active packaging systems related to the need for safe finished products with a long shelf life. To obtain the films, Cannabis sativa L. herb extract was used as the active agent. The samples with the highest extract contents of 20:80 2.0F and 80:20 2.0F (PA:PC ratio + wt.% extract) were characterized by a polyphenols content of 0.9067 ± 0.0184 [%]. They also showed the highest antioxidant activity, at ABTS = 1.79 ± 0.04 [mg/mL] and DPPH = 4.44 ± 0.10 [mg/mL]. Mechanical tests conducted showed that samples without extract addition, regardless of the pectin apple to citrus ratio, were characterized by similar values of mechanical parameters (p > 0.05). Spearman’s rank correlation coefficients were used to demonstrate the strength and direction of the relationship between pairs of variables. Statistical analysis showed strong correlations between antioxidant indices and polyphenol content.

In the present paper, extracts from pomace after cherry wine production were used as biocomponents of antioxidant packages. In the study, the highest concentrations of polyphenolic compounds were obtained when a 50% ethanol solution was used as the extraction solution. The addition of extracts provided statistically significant (p < 0.05) changes in water vapor transmission for the films obtained. The WVTR results are at a very low level, as values ranging from 7.96 ± 0.33 [g/m² d] (sample 2) to 10.95 ± 0.33 [g/m² d] (sample 1) were obtained. The addition of extract also affected the oxygen barrier. Samples without extract addition showed an OTR value of 2.42 ± 0.23 [cm³/m² d 0.1 MPa]. A statistically significant (p < 0.05) reduction in this parameter was affected by the addition of extract to the matrix. Oxygen barrier properties ranged from 0.50 ± 0.05 (sample 3) to 0.94 ± 0.04 (sample 1), indicating high barrier properties of the packaging material. The addition of extracts caused an increase in opacity: films 3 and 4 were characterized by the highest value of the parameter, which was, respectively: 18.14 ± 27.02 and 18.97 ± 29.83 [%]. The research carried out in this study allows us to conclude that bioactive films with high application potential have been achieved and, in addition, represent a natural and ecological alternative to the materials currently used.

In this work, we developed an antioxidant and antibacterial red pectin food packaging material with natural Hibiscus sabdariffa flos. This study showed that this red pectin film (PJH, PCH, PCJH) containing Hibiscus extract exhibited antioxidant activity. The addition of hibiscus improved the barrier properties. The WVTR parameter values for the PJH, PCH and PJCH samples were as follows: 4.87 [g/m²d], 4.45 [g/m²d], and 4.48 [g/m²d]. The addition had a significant effect on the L* of the samples, i.e., PJH, PCH and PJCH films. This is a useful effect for films of selected products or product groups. Microbiological analyses of our red pectin films showed that they had an inhibitory effect on the growth of Listeria monocytogenes. In the case of the Staphylococcus aureus strain, the inhibitory effect was shown by films that contained hibiscus extract: PJH, PCH and PJCH. This means that the added hibiscus increased the antimicrobial activity of our red films. An additional advantage of our pectin films is their red colour, which, in addition to its protective and ecological function, also plays a marketing role.

In the packaging materials sector, increasing globalization has created the need for increased efforts to develop consumer protection measures. Consequently, new packaging materials are being sought to replace petroleum-based materials in the future. For this reason, global awareness of the environmental problems associated with the use of synthetic and non-degradable packaging has increased the attention paid to bio-packaging based on natural and biodegradable polymers. The bio-packaging sector is developing innovations to address the sustainability issues facing the food packaging industry. Our research has shown that green matcha extract can be a promising source of antioxidants for the production of bioactive pectin films. This study further confirmed that green matcha extract can be a promising source of antioxidants for the production of bioactive pectin films. The antioxidant activity test showed high activity of films containing matcha extract. The antioxidant activity of films without matcha addition, P, PJ, PC, PJC, was negligible. The addition of matcha to the polymer matrix did not significantly affect the mechanical properties (TS, EB) of the films obtained. The addition of cellulose had the greatest effect on changing the mechanical properties. It caused a twofold increase in the mechanical properties of the obtained packaging films. The addition of matcha significantly improved the barrier properties (for PM films, the WVTR was 3.40 [g/m²d]; for PJM films the WVTR was 1.70 [g/m²d]). The green packaging films showed no toxic effects on the plants (Phacelia tanacetifolia, Salvia hispanica, Brassica napus) and invertebrates (Daphnia pulex, Chaoborus, Chironomus aprilinus) tested. The half-solubility time of the membranes in a solution mimicking gastric acid was also determined. The longest half-dissolution time of the films was about 2 min. Our research has therefore shown that the biodegradable and environmentally safe green packaging films with antioxidant activity that we have developed can be used as edible functional casings in the future, e.g., for sausages and other food products.