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We investigated the influence of three different paraffin chain sizes (C22, C28, and C36) on the outflow profile of oil dissolved in mineral oil using thermal lens spectrometry (TLS) coupled with laser-induced fluorescence spectrometry (LIFS). The data show that the presence of paraffin molecules leads to an increase in the fluorescent quantum yield of natural oil probes, as observed by the reduction of the photothermal signal and the consequently increased fluorescent emission. We also observe that larger paraffin molecules such as C36 tend to move toward the bottom layer during the fluid outflow. This may be associated with the nucleation process and formation of paraffinic deposits in oil ducts. [ABSTRACT FROM AUTHOR]

• Cyclolaudenol was the major constituent of the green propolis extract. • Brazilian green propolis showed great potencial for fish bilayer coating. • Antibacterial and antioxidant activity of propolis aid in the conservation of fish fillets. • The sodium alginate bilayer coating showed high sensorial acceptance. Fish deterioration imposes great economic losses and serious human health hazards. The objective of this work was to evaluate the effect of a sodium alginate bilayer coating incorporated to the green propolis extract in shelf-life, physical–chemical properties, microbiological properties and sensory acceptance of Colossoma macropomum fillets. Additionally, the chemical composition, along with the antioxidant and antibacterial activities of Brazilian green propolis extract (GPE) were investigated. GPE showed promising antioxidant and antibacterial activities. Twenty-seven metabolites were identified by gas chromatography (GC–MS), which mainly comprised terpenoids (52.14%). Cyclolaudenol was the major constituent of the GPE and it is described for the first time in green propolis extracts. C. macropomum fillets treated with the sodium alginate bilayer coating showed high sensory acceptance, reduced microbial deterioration and extended shelf-life (up to 11 days) during cold storage. Taken together, these results show that GPE can be a great alternative of a natural preservative for fish coating. [ABSTRACT FROM AUTHOR]