Degradation kinetics of anthocyanin and physicochemical changes in fermented turnip juice exposed to pulsed UV light.

In this study, the effects of pulsed UV (PUV) light on the degradation kinetics of anthocyanins and physicochemical properties of turnip juice were investigated. PUV light was applied to turnip juice at 3 different distances (5, 8, 13 cm) from the quartz window of the xenon lamp for 5 different times (5, 15, 30, 45, 60 s). The pH, total acidity (% lactic acid), monomeric anthocyanin content, color density, hue, brightness, and percent color components (yellow, red, and blue) of turnip juice changed significantly after PUV-light treatments at each level. The maximum degradation of anthocyanin after PUV-light treatments was found to be about 63%. The anthocyanin degradation, brightness, yellow and blue color (%) increased, while red color (%) decreased with longer treatment time and shorter distance. The degradation of monomeric anthocyanins in turnip juice exposed to PUV light was described by the Weibull model (R2 0.982-0.998, RMSE 0.087-0.133) more accurately than the first-order kinetics (R2 0.906-0.992, RMSE 0.071-0.192).

Production of red beetroot juice by different methods: Kinetics of microbial growth, sugar consumption, and acid production.

As a fermentation method, the utilisation of starter culture is a common practice in industrial manufacturing, although spontaneous methods have been employed since ancient times. The objective of this study was to investigate the effect of different production methods on red beetroot juice (RBJ). For this purpose, as a starter culture, the probiotic Lactibasillus paracasei (Lc. paracasei) was inoculated into the RBJ samples after pasteurization. Also, the growth of cells, acid production, and substrate utilisation were monitored throughout the fermentation process of RBJ under two different methods of fermentation. The samples produced by the addition of Lc. paracasei demonstrated a slightly lower decrease in pH values in comparison to the samples obtained by the spontaneous method. The concentration of lactic acid (LA) and acetic acid (AA) at the end of fermentation reveals that Lc. paracasei exhibits a greater capacity for both LA and AA generation compared to the spontaneous method. The ratios of LA and AA molar concentrations of RBJ were determined to be 1.7 and 3.6 for the samples produced by adding Lc. paracasei and the spontaneous method, respectively. The samples produced by adding Lc. paracasei exhibited a greater consumption of sucrose. Both fermentation methods provide LAB counts exceeding 8 log CFU/mL at the end of fermentation. Time demonstrated a significant correlation with LA and AA in the method by adding Lc. paracasei (r = 0.942 and 0.745), respectively (p < 0.01). In both methods, it was demonstrated that while sucrose content decreased during the fermentation period, fructose and glucose content remained constant (p < 0.05).

Mild Pretreatments to Increase Fructose Consumption in Saccharomyces cerevisiae Wine Yeast Strains.

The present research investigates the effect of different pretreatments on glucose and fructose consumption and ethanol production by four Saccharomyces cerevisiae wine strains, three isolated and identified from different wine regions in Turkey and one reference strain. A mild stress temperature (45 °C, 1 h) and the presence of ethanol (14% v/v) were selected as pretreatments applied to cell cultures prior to the fermentation step in synthetic must. The goodness fit of the mathematical models was estimated: linear, exponential decay function and sigmoidal model were evaluated with the model parameters R2 (regression coefficient), RMSE (root mean square error), MBE (mean bias error) and χ2 (reduced Chi-square). Sigmoidal function was determined as the most suitable model with the highest R2 and lower RMSE values. Temperature pretreatment allowed for an increase in fructose consumption rate by two strains, evidenced by a t90 value 10% lower than the control. One of the indigenous strains showed particular promise for mild temperature treatment (45 °C, 1 h) prior to the fermentation step to reduce residual glucose and fructose in wine. The described procedure may be effective for indigenous yeasts in preventing undesirable sweetness in wines.

Ischemia-modified albumin levels in patients with end-stage renal disease patients on hemodialysis: does albumin analysis method affect albumin-adjusted ischemia-modified albumin levels?

Ischemia-Modified albumin (IMA) has been used as an early marker in the evaluation of the patients with acute coronary syndrome. We aimed to evaluate IMA in end-stage renal disease (ESRD) patients on hemodialysis and the effect of albumin methods on albumin-adjusted IMA levels. A total of 30 ESRD patients were included in this study. Serum IMA and albumin levels were measured before and after a hemodialysis session. Albumin concentrations were determined with bromocresol green and bromocresol purple methods. Postdialysis IMA and albumin-adjusted IMA levels with two different albumin methods were significantly increased compared with the predialysis levels (P<0.05). However, we did not find any difference in albumin-adjusted IMA levels in either at the beginning or at the end of the dialysis session. IMA levels increase after hemodialysis, whereas albumin method has no effect on albumin-adjusted IMA levels.