Effect of Ultra-High Pressure Homogenization (UHPH) and Conventional Thermal Pasteurization on the Volatile Composition of Tiger Nut Beverage.

Tiger nut beverages are non-alcoholic products that are characterized by their pale color and soft flavor. Conventional heat treatments are widely used in the food industry, although heated products are often damaging to their overall quality. Ultra-high pressure homogenization UHPH) is an emerging technology that extends the shelf-life of foods while maintaining most of their characteristics.

Predictability of gene ontology slim-terms from primary structure information in Embryophyta plant proteins.

Background: Proteins are the key elements on the path from genetic information to the development of life. The roles played by the different proteins are difficult to uncover experimentally as this process involves complex procedures such as genetic modifications, injection of fluorescent proteins, gene knock-out methods and others. The knowledge learned from each protein is usually annotated in databases through different methods such as the proposed by The Gene Ontology (GO) consortium.

Ultrastructural changes of sparkling wine lees during long-term aging in real enological conditions.

Ultrastructural changes of lees of three series of sparkling wines produced using the traditional method during long-term aging (4 years) were assessed by high-pressure freezing in combination with transmission electron microscopy. The stratified structure of the cell wall disappeared throughout aging. After 18 months, the microfibrous material of the cell wall appeared more diffuse and the amorphous midzone of the inner wall layer was progressively degraded.

Changes in the sorption of diverse volatiles by Saccharomyces cerevisiae lees during sparkling wine aging.

The volatile profile of sparkling wine is influenced by the retention and release of volatile compounds by lees during the aging process. Here we attempted to identify the volatiles that are most retained by lees in aging conditions and to study how their sorption varies during aging. We estimated the lees sorption capacity for several representative volatile compounds in sparkling wine samples at a range of time points during aging by assessing the volatiles sorbed on the lees surface and those present in the corresponding wines.

Antioxidant activity of lees cell surface during sparkling wine sur lie aging.

Given the importance of the interactions between wine and lees cell surface during sparkling wine aging, and in view of recent results proving the antioxidant potential of yeast cell wall biomolecules, the antioxidant capacity of lees cell surface was investigated to establish its possible role in the antioxidative effect of lees. The surface antioxidant activity of lees from wines with different aging periods was determined on the whole cell by two widely used methods (DPPH and FRAP assays), obtaining maximum values of 24.5micromol Trolox/g cells (fresh weight) by the DPPH assay, and 21.

Surface properties of Saccharomyces cerevisiae lees during sparkling wine ageing and their effect on flocculation.

Cell surface properties were determined for the first time for lees of Saccharomyces cerevisiae, and they proved to be significantly dependent on the time of sparkling wine ageing on lees. Cell surface hydrophobicity decreased from approximately 44% to 11% of affinity to hexadecane. Electron acceptor capacity (calculated as % affinity to ethyl acetate-% affinity to decane) increased from approximately -27% to 10 % and zeta potential from approximately -4 to 6mV.