Influence of non-thermal processing techniques on sulfur dioxide and oxygen concentrations in young and aged wines

Abstract

The application of innovative techniques like high hydrostatic pressure (HHP) and high power ultrasound (HPU) for food processing and preservation is one of the current topics in food science. In the enological field, these techniques have been identified as alternative methods for wine microbial stabilization and acceleration of wine aging process. Due to lack of available information about their influence on physicochemical characteristics, the aim of this work was to study the effect of HHP and HPU on sulfur dioxide and dissolved oxygen concentrations in red and white wines. The effect was evaluated immediately after the treatment and after 3, 6 and 12 months of aging in bottles. Moreover, the synergistic effect of mentioned techniques along with antioxidants additions (glutathione and SO2) was also evaluated. The results showed that the concentrations of free and total SO2 did not change immediately after HHP treatments, while after HPU processing there was no clear trend in analyzed parameters. As expected, results showed that both, free and total SO2 decreased during storage period of red and white wines. Regarding both applied techniques, slightly higher concentrations of free SO2 were observed in samples treated by HHP after 12 months of storage. Oxygen concentration slightly increased immediately after the treatments, with the highest concentration determined after HPU processing. During aging, its concentrations decreased and were similar or slightly higher than of those determined in untreated samples. Regarding the antioxidants additions, better protective effect was obtained by addition of higher concentration of SO2 than glutathione, since these samples were characterized by lower concentrations of dissolved oxygen.

Phenolic and Aroma Changes of Red and White Wines during Aging Induced by High Hydrostatic Pressure

“…Namely, the dissolved oxygen was measured using a luminescent dissolved-oxygen sensor (NomaSense™ O 2 P6000, Nomacorc, Belgium), and the obtained values ranged from 1.2 to 1.9 mg/L in control wines and 1.9 to 2.6 mg/L in pressurized red and white wines, respectively. As already presented in our previous work, the total and free SO 2 were also determined by potentiometry using a sulfur dioxide measurement device (LDS Sulfilyser, Laboratories Dujardin-Salleron, Noizay, France), and the results showed 20 and 10 mg/L of total and free SO 2 in pressurized and control red wines, as well as 70 and 25 mg/L of total and free SO 2 in pressurized and control white wines, respectively [ 29 ]. Figure 1 shows a schematic diagram of experimental variables applied during HHP treatment of the wines.…”

“…As already presented in our previous work [ 29 ], the concentrations of dissolved oxygen, total and free SO 2 were also controlled at the point of bottling and during 12 months of aging. As previously mentioned in Section 2.1 ., we used the same analytical methods and the results showed that the initial levels of dissolved oxygen at bottling in red wine amounted up to 2.2 mg/L in both pressurized and control wines, while after 12 months the levels were in the range from 0.4 to 0.6 mg/L.…”

“…The wines’ color and phenolic composition were analyzed immediately after performed pressurization. Besides that, the analyses of physicochemical parameters such as dissolved oxygen, total and free SO 2 were also performed and have already presented in our previous work [ 29 ]. Namely, the dissolved oxygen was measured using a luminescent dissolved-oxygen sensor (NomaSense™ O 2 P6000, Nomacorc, Belgium), and the obtained values ranged from 1.2 to 1.9 mg/L in control wines and 1.9 to 2.6 mg/L in pressurized red and white wines, respectively.…”

“…As previously mentioned in Section 2.1 ., we used the same analytical methods and the results showed that the initial levels of dissolved oxygen at bottling in red wine amounted up to 2.2 mg/L in both pressurized and control wines, while after 12 months the levels were in the range from 0.4 to 0.6 mg/L. In the case of white wine, the initial levels were around 1.1 and 1.4 mg/L in control and pressurized samples, while at the end of aging the levels amounted up to 0.3 and 0.6 mg/L in control and pressurized samples, respectively [ 29 ]. During aging, pressurized standard SO2 wines (red and white) showed similar or slightly lower levels of total and free SO 2 compared to untreated ones, amounting around 20 and 15 mg/L in the red wine and 80 and 25 mg/L in the white wine after 12 months.…”

“…During aging, pressurized standard SO2 wines (red and white) showed similar or slightly lower levels of total and free SO 2 compared to untreated ones, amounting around 20 and 15 mg/L in the red wine and 80 and 25 mg/L in the white wine after 12 months. Also, the standard SO 2 wines were characterized by lower amounts of dissolved oxygen, whereas the addition of GSH had no significant effect on oxygen and SO 2 consumption rate in the red and white wines [ 29 ].…”