Analytical methods in wineries: is it time to change?

A review of the methods for the most common parameters determined in wine—namely, ethanol, sulfur dioxide, reducing sugars, polyphenols, organic acids, total and volatile acidity, iron, soluble solids, pH, and color—reported in the last 10 years is presented here. The definition of the given parameter, official and usual methods in wineries appear at the beginning of each section, followed by the methods reported in the last decade divided into discontinuous and continuous methods, the latter also are grouped in nonchromatographic and chromatographic methods because of the typical characteristics of each subgroup. A critical comparison between continuous and discontinuous methods for the given parameter ends each section. Tables summarizing the features of the methods and a conclusions section may help users to select the most appropriate method and also to know the state-of-the-art of analytical methods in this area

Uptake of Hydrocarbon by Pseudomonas fluorescens (P1) and Pseudomonas putida (K1) Strains in the Presence of Surfactants: A Cell Surface Modification

The objective of this research was the evaluation of the effects of exogenous added surfactants on hydrocarbon biodegradation and on cell surface properties. Crude oil hydrocarbons are often difficult to remove from the environment because of their insolubility in water. The addition of surfactants enhances the removal of hydrocarbons by raising the solubility of these compounds. These surfactants cause them to become more vulnerable to degradation, thereby facilitating transportation across the cell membrane. The obtained results showed that the microorganism consortia of bacteria are useful biological agents within environmental bioremediation. The most effective amongst all, as regards biodegradation, were the consortia of Pseudomonas spp. and Bacillus spp. strains. The results indicated that the natural surfactants (rhamnolipides and saponins) are more effective surfactants in hydrocarbon biodegradation as compared to Triton X-100. The addition of natural surfactants enhanced the removal of hydrocarbon and diesel oil from the environment. Very promising was the use of saponins as a surfactant in hydrocarbon biodegradation. This surfactant significantly increases the organic compound biodegradation. In the case of those surfactants that could be easily adsorbed on cells of strains (e.g., rhamnolipides), a change of hydrophobicity to ca. 30–40% was noted. As the final result, an increase in hydrocarbon biodegradation was observed

Modification of cell surface properties of Pseudomonas alcaligenes S22 during hydrocarbon biodegradation

Biodegradation of water insoluble hydrocarbons can be significantly increased by the addition of natural surfactants one. Very promising option is the use of saponins. The obtained results indicated that in this system, after 21 days, 92% biodegradation of diesel oil could be achieved using Pseudomonas alcaligenes. No positive effect on the biodegradation process was observed using synthetic surfactant Triton X-100. The kind of carbon source influences the cell surface properties of microorganisms. Modification of the surface cell could be observed by control of the sedimentation profile. This analytical method is a new approach in microbiological analysis

Effect of Salt on the Hydrophobicity Parameters of Nonionic Surfactants

The lipophilicity and specific hydrophobic area of 56 surfactants having different hydrophobic moieties and different lengths of ethylene oxide chain were determined by reversed-phase thin-layer chromatography. The effect of sodium chloride and pH on the hydrophobicity parameters were elucidated using spectral mapping technique followed by two dimensional nonlinear mapping. In each instance significant linear correlations were found between the lipophilicity and specific hydrophobic surface area of surfactants suggestingthat from a chromatographicpoint of view they behave as a homologous series of solutes. It was established that the strength ofthe effect of both salt concentration and pH is relatively low and the selectivity of their influence on the hydrophobicity parameters is markedly different

Stability of pigments of paprika [Capsicum annuum] powders during various processing steps

The effects of various technological steps and raw material inhomogeneity on the composition of pigments in paprika (Capsicum annuum) powders were studied by reversed-phase high-performance liquid chromatography (RP-HPLC), using gradient elution technique (various mixtures of water, acetonitrile and methanol) and diodearray detector. The standard deviation of the composition of pigments in the samples taken at different technological stages was lower than among the batches of raw material. This indicates that the technological steps have a negligible effect on the composition of pigments in paprika powder. It was further found that the raw material for the paprika powder manufacture could considerably be inhomogeneous even when harvested on the same field