Improvement in sensory characteristics of Campbell Early wine by adding dual starters of Saccharomyces cerevisiae and Oenococcus oeni.

This study was performed to investigate the effects of adding a dual starter on the chemical and sensory characteristics of red wine made of Campbell Early grape. The yeast starter, Saccharomyces cerevisiae, and lactic acid bacteria (LAB) starter, Oenococcus oeni, were used for inoculation in the winemaking process for alcoholic and malolactic fermentation (MLF), respectively. After 200 days incubation, the chemical compositions of yeast/LAB-added wine (YL-wine) were compared with those of no starter-added wine (control) and yeast-added wine (Y-wine). The results show that no significant differences were observed in pH, total sugar, and alcohol content among wine samples, but the malic acid content in YL-wine was significantly reduced and various esters and higher alcohols were synthesized. The sensory test revealed that the addition of dual starters resulted in improved overall acceptability in wine. This study emphasizes the importance of O. oeni in addition to yeast in making Campbell Early wine.

Ultrasound-assisted electrochemical treatment for phenolic wastewater.

With the rapid development of industry, especially the rapid rise of the chemical industry, the problem of water pollution is becoming more and more serious. Among them, the discharge of organic pollutants represented by phenolic substances has always been at the forefront. In this paper, ultrasound-assisted electrochemical treatment for phenolic wastewater is investigated. The effects of ultrasonic frequency, current, pH value and the amount of fly ash-loaded titanium TiO2-Fe3+ particles on phenol removal from phenol-containing wastewater are investigated. The experimental results demonstrate that the removal rate of phenol in phenol-containing wastewater is the best when ultrasonic frequency is 45 kHz, power is 200 W, the current is 1.2 A, pH is 5 and the dosage of fly ash-loaded titanium TiO2-Fe3+ particles is 3 g. In addition, microwave-assisted-Fenton reagent treatment for phenol wastewater is investigated. The effects of Fenton reagent dosage, initial pH value, microwave power density and radiation time on phenol degradation rate are investigated. The results show that microwave can accelerate the reaction rate, reduce the number of metal ions, save the process cost and reduce the difficulty of post-treatment. Finally, the research status of phenol wastewater treatment technology at the present stage is reviewed, and the future development direction is discussed.

Monitoring of Leuconostoc population during sauerkraut fermentation by quantitative real-time polymerase chain reaction.

A real-time PCR assay method was established to monitor Leuconostoc spp. populations via specific amplification of the dextransucrase gene. Quantification of L. mesenteroides B-512F using both genomic DNA and cell suspensions yielded a log-linear correlation spanning approximately 5 log units. By using this method, monitoring changes of Leuconostoc spp. during sauerkraut fermentation was successfully accomplished with accuracy after inoculation of starter and sugars (sucrose and maltose).

Antimicrobial treatment of grapes using sodium hypochlorite in winemaking and its effects on the chemical and sensory characteristics of wines.

This study was performed to examine the use of NaOCl as an alternative antimicrobial compound in winemaking because of the potential health problems that may arise as a result of the use of SO2. For this, the blank (non-treated), control (SO2-added), and sample (NaOCl-treated) wines were made, and microbial and chemical changes including sensory characteristics were analyzed during the fermentation periods. Treatment of grapes with NaOCl decreased the initial contaminating microbial population in grape must, resulting in higher growth of yeast and lactic acid bacteria. After 200 days of fermentation, the chemical analysis of sample wine revealed that it had higher ethanol content, redness (a*), and concentrations of fruity ester compounds and lower total acidity than the control. In the sensory analyses, the sample wine obtained a higher overall acceptability score (5.70) than the control (4.26). This result reveals that NaOCl can be used as an alternative to SO2 in winemaking for inhibiting the growth of contaminating microorganisms.