Extraction of hops pelletized (Humulus lupulus) with subcritical CO2 and hydrodistillation: Chemical composition identification, kinetic model, and evaluation of antioxidant and antimicrobial activity

Optimization of Antifungal Properties of Hop Cone Carbon Dioxide Extracts Based on Response Surface Methodology

Response surface methodology (RSM) was employed to optimize the process parameters of the supercritical carbon dioxide extraction of hop cones in terms of their antifungal properties against Fusarium culmorum and Aspergillus niger. The effects of temperature (40-50 °C), pressure (200-300 bar), and CO2 consumption (25-75 kgCO2/kg) on the extraction yield, content of α- and β-acids, as well as pathogens' growth inhibition were investigated. Both pressure and CO2 consumption had a significant effect on antifungal properties. It was observed that the best results for antifungal properties were obtained when hop cones were extracted with pure carbon dioxide at the temperature of 50 °C, under the pressure of 300 bar with CO2 consumption at the level of 75 kgCO2/kg of feed for extraction. The highest antifungal properties of hop cone supercritical carbon dioxide extracts were analyzed as 100% for Fusarium culmorum and 68% for Aspergillus niger, calculated as the growth inhibition of tested pathogens. The aim of the study was to determine the optimum values of extraction parameters to achieve the maximum response and enable us to investigate the interaction of these parameters on the antifungal properties of hop cone extracts.

Antioxidant Activity of Humulus lupulus Phenolic Hop Extracts in Creating a New Pâté: An Element Affecting Fat Stability and Microbiological Quality during Storage

The aim of this study was to evaluate the effect of hop extracts on changes in the primary and secondary fat oxidation products, physicochemical properties, and microbiological quality of pâté-type offal sausages obtained through the partial replacement of animal fat with vegetable fat. This study demonstrated that the extraction efficiency varied among hop cone varieties, with the highest efficiency observed for the Lubelski variety and the lowest for the Magnum variety. The phenolic compound content was higher in the Magnum cones (2.74 ± 0.11 mg/g dry matter) compared to the Lubelska cones (2.27 ± 0.05 mg/g of product). Additionally, the DPPH radical scavenging activity was greater in the extract from the Magnum cones (4.21 ± 0.09 mg TE/g d.w.) than in the extract from the Lublelski cones (3.87 ± 0.05 mg TE/ g d.w.). Similarly, the extracts from the Lubelski cones exhibited a higher antiradical activity against the ABTS radical compared to the extract from Magnum cones. Throughout storage, a significant increase in the pH value was observed in the control sample and in the samples with a 20% replacement of animal fat with rapeseed oil and Magnum hop extract. However, the addition of Lubelski hop extract resulted in a decrease in the pH value during the 15-day storage period. The samples with a 20% replacement of animal fat with rapeseed oil and 0.1% Lubelski hop extract showed the least changes in water activity during storage. The samples with a 20% replacement of animal fat with rapeseed oil and the addition of 0.2% Lubelski hop extract had the lowest peroxide value and TBARS index throughout the storage period. The addition of hop extract inhibited the growth of the total number of microorganisms in the tested sausages. In the samples with a 20% replacement of animal fat with rapeseed oil, the content of aerobic microorganisms, compared to the control sample, was statistically significantly lower.

Extraction and Separation of Natural Products from Microalgae and Other Natural Sources Using Liquefied Dimethyl Ether, a Green Solvent: A Review

Microalgae are a sustainable source for the production of biofuels and bioactive compounds. This review discusses significant research on innovative extraction techniques using dimethyl ether (DME) as a green subcritical fluid. DME, which is characterized by its low boiling point and safety as an organic solvent, exhibits remarkable properties that enable high extraction rates of various active compounds, including lipids and bioactive compounds, from high-water-content microalgae without the need for drying. In this review, the superiority of liquefied DME extraction technology for microalgae over conventional methods is discussed in detail. In addition, we elucidate the extraction mechanism of this technology and address its safety for human health and the environment. This review also covers aspects related to extraction equipment, various applications of different extraction processes, and the estimation and trend analysis of the Hansen solubility parameters. In addition, we anticipate a promising trajectory for the expansion of this technology for the extraction of various resources.