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Malolactic fermentation (MLF) is a challenging and time-consuming step in the winemaking process. The effects of climate change are making the intrinsic conditions in red wine more challenging for the growth of lactic acid bacteria through interfering with a prompt and effective MLF. However, this is a necessary process in red wine production that contributes to high quality of wine demanded by consumers. Previous studies in our group reported a highly efficient MLF of red wine by using encapsulated Oenococcus oeni. Here, we designed a bench-scale packed-bed reactor using encapsulated bacteria to facilitate and speed up this process. The time to complete MLF was reduced as the concentration of biocapsules increased. The system exhibited operational stability and efficiency in sequential batches of wine recirculated through the column. Furthermore, an efficient continuous MLF was achieved using the packed-bed reactor. In general, a slight reduction in the concentration of some volatile organic compounds (VOCs) in the wines from the continuous system was observed as compared to those from the recirculated system. [ABSTRACT FROM AUTHOR]

Autolysis plays a crucial role as a technological tool in the ageing process of specific wines. This includes white, red and sparkling wines. During ageing on the lees, yeasts release different compounds that positively modify the composition of the wine. However, traditional autolytic methods can be time-consuming. This work evaluates the use of different ultrasound (US) and high hydrostatic pressure (HHP) treatments to expedite the autolytic process in Saccharomyces cerevisiae in a model wine system. The results suggest that treating yeast cells with US resulted in a faster release of nucleic acids, proteins, and total polysaccharides compared to HHP treatment. The environmental scanning electron microscopy (ESEM) of the treated lees demonstrated that the impact on the yeast cell surface was more pronounced after exposure to US compared to treatments involving HHP. In conclusion, under these conditions the US treatment effectively triggered autolysis in the wine yeast strain, facilitating the release of macromolecules in a model wine. [ABSTRACT FROM AUTHOR]

Abstract: Parkinson’s disease is the second most common neurodegenerative disease, after Alzheimer’s disease, among the aging human population. The main symptoms of Parkinson’s disease such as tremor and movement disabilities are the result of degeneration of dopaminergic neurons in substantia nigra pars compacta. The widely-accepted subcellular factor which underlies Parkinson’s disease neuropathology is the presence of Lewy bodies with characteristic inclusions of aggregated alpha-synuclein. This small soluble protein has been implicated in a range of interactions with phospholipid membranes and free fatty acids. The precise biological function of this protein is, however, still under investigation. Here we review the evidence linking alpha-synuclein, lipid metabolism, fatty acid oxidation, mitochondrial damage and Parkinson’s disease. We propose that association of alpha-synuclein with oxidized lipid metabolites can lead to mitochondrial dysfunction in turn leading to dopaminergic neuron death and thus to Parkinson’s disease. [Copyright &y& Elsevier]

Highlights • Combination of ALG and SiO 2 enhances chemical stability of biocapsules in wine. • Inclusion of SiO 2 improves the operational stability of ALG-based biocapsules. • SiO 2 -ALG biocapsules can be reused efficiently in low-pH or high-ethanol wines. • SiO 2 -ALG entrapped bacteria achieve a successful MLF under adverse conditions. Abstract Oenococcus oeni was encapsulated into inter-penetrated polymer networks of silica-alginate (SiO 2 -ALG). Fourier transform infrared spectroscopy analysis proved the presence and the polycondensation of the siliceous material used in SiO 2 -ALG capsules. Environmental scanning electron microscopy showed that the structure of SiO 2 -ALG biocapsules was rougher than in alginate (ALG) biocapsules. The behaviour of SiO 2 -ALG biocapsules was evaluated at pH 3.0–3.6 and alcohol degrees of 12–15%. Repeated-batch malolactic fermentations (MLF) demonstrated that SiO 2 -ALG biocapsules can be reused efficiently for five times in either low-pH or high-ethanol wines, while free bacteria only can be used once under the most favourable MLF conditions. The inclusion of siliceous materials into ALG hydrogel improved the stability of the biocapsules, reducing their shrinking and achieving an excellent integrity under winemaking conditions. These results proved the possibility of industrial application of SiO 2 -ALG biocapsules in winemaking. [ABSTRACT FROM AUTHOR]

Cell encapsulation is used as a biotechnology tool to solve the technological problems derived from handling and application of cells in a great range of fields. This involves immobilization of the cells within a polymeric gel that permits the preservation of their metabolic activity. Alginate is widely established as the most suitable polymer for cell encapsulation. However, alginate gel capsules suffer several disadvantages because of their lack of mechanical and chemical stability. This review summarizes results of recent advances in coating techniques that include ionic and covalent cross-linking between alginate and coating materials for cell encapsulation as a strategy to solve the disadvantages mentioned before. Throughout this review, physicochemical properties of coated-alginate capsules and the effect of coating process on metabolic activity and viability of immobilized cells have been specially discussed. [ABSTRACT FROM AUTHOR]

• Simultaneous AF/MLF using free and encapsulated LAB reduced the fermentation time. • Timing of inoculation modified wine volatile, amino acid and biogenic amine content. • Only the volatile and amino acid profile of the wine was modified by the type of inoculum. • Sensory analysis did not detect significantly differences among wines. • Wines elaborated with encapsulated LAB and lysozyme completed MLF. The influence of the timing of inoculation (sequential and simultaneous alcoholic fermentation (AF)/malolactic fermentation (MLF)) on the chemical and sensory properties of red wines was studied. The impact of the encapsulation of Oenococcus oeni into SiO 2 -alginate hydrogel (Si-ALG) and the addition of lysozyme in wines inoculated with encapsulated bacteria were also analysed. There was a significant influence of the timing of inoculation on the volatile composition of the wines just as on the amino acid and biogenic amine content. The wines produced by simultaneous AF/MLF showed the highest contents of some volatile compounds, such as ethyl esters and terpenes, as well as amino acids and tyramine. Bacterial encapsulation affected the volatile and amino acid profile of the wines, while the biogenic amine composition was not modified. The chemical composition of the wines was not altered by the presence of lysozyme. A trained panel did not perceive substantial differences between treatments. [ABSTRACT FROM AUTHOR]