Wine, a drink originating from ancient times, has become the favorite of countless wine lovers around the world with its unique taste and rich cultural connotations. However, when we look closely at the Chinese back labels of imported wines, we often find a slightly disturbing ingredient – sulfur dioxide. After all, sulfur dioxide is often associated with air pollution sources such as acid rain and car exhaust and is considered a hazardous substance. So why is this ingredient added to wine, which is known as a healthy drink?
The Key to Preserving Wine During the development of wine, preservation has always been a vexing issue. Once wine is exposed to air, it quickly becomes sour due to oxidation. In the early days, people tried various methods to reduce the contact between wine and air, but the results were limited. With the advancement of technology , airtight glass containers and vacuum stoppers have emerged, effectively extending the storage time of wine. However, wine, as a living drink, requires a small amount of oxygen during the maturation process in the bottle. Although complete isolation of air can prevent oxidation, it is not conducive to the maturation and flavor development of wine.
Oxidation and Protection of Wine During the fermentation process of wine, yeast converts the sugar in the grape juice into alcohol, but some sugar always remains. These residual sugars become a breeding ground for bacteria. At the same time, wine itself has many health benefits, one of which is its natural antioxidant properties, which help with anti-aging. However, as an antioxidant, wine itself is also susceptible to the effects of oxidation. Therefore, more powerful antioxidants need to be added to protect their antioxidant activity.
The Multiple Roles of Sulfur Dioxide in Wine Production In wine production, sulfur dioxide is added not only to deal with potential microbial contamination, but also to achieve multiple winemaking goals:
Bactericidal effect : Sulfur dioxide can effectively inhibit the activities of bacteria, yeast and other microorganisms in wine, thereby extending the shelf life of wine and preventing deterioration caused by microbial activities.
Antioxidant effect : Phenolics in wine are susceptible to oxidation, resulting in loss of flavor. The addition of sulfur dioxide slows this process and preserves the wine’s natural fruit character and color.
Clarification effect : An appropriate amount of sulfur dioxide can promote the settlement of suspended solids in grape juice, accelerate the clarification process, and create favorable conditions for subsequent fermentation and storage.
Dissolution : Sulfur dioxide helps dissolve pigments, flavor substances and inorganic salts in the peel, enhancing the color and flavor complexity of the wine.
Control standards for sulfur dioxide addition . Among many possible antioxidants, sulfur dioxide has become the first choice in the wine industry due to its excellent performance and long history of use. People have been adding sulfur dioxide to wine for hundreds of years, and no better alternative has yet been found. Sulfur dioxide can not only effectively prevent wine from being oxidized, but also inhibit the growth of bacteria and maintain the purity and flavor of wine. It is worth noting that during the yeast fermentation process, a certain amount of sulfur dioxide will be naturally produced, but this amount is far from sufficient to meet the needs of antioxidant and preservation, so additional addition is required.
Although sulfur dioxide plays a vital role in the wine-making process, its potential harm to human health cannot be ignored. Ingesting too much sulfur dioxide at one time may cause acute poisoning, and in severe cases may even cause pulmonary edema, suffocation and coma.
The amount of sulfur dioxide added to wine is strictly regulated due to its potential health risks. According to the national standard GB15037, whether it is imported wine or domestic wine, the total sulfur content of dry, semi-dry and semi-sweet wines shall not exceed 250 mg/L, and the total sulfur content of sweet wine shall not exceed 400 mg/L. However, in actual production, many wineries often control the addition amount in a lower range due to quality considerations, usually between 100 and 150 mg/L. This requires winemakers to accurately control the amount of sulfur dioxide added to achieve the best brewing effect.
In order to accurately monitor and control the sulfur dioxide content in wine, the sulfur dioxide distillation instrument and its built-in high-precision sensor have become an indispensable tool in the winemaking process.
Sulfur dioxide distillation instrument and its sensor application In order to achieve precise monitoring and control of sulfur dioxide, sulfur dioxide distillation instrument has become a key equipment in wine production. The instrument heats and distills the sample, causing the sulfur dioxide to evaporate with the steam, and then collects it through condensation, and finally measures its content through a built-in sensor.
The British Alphasense sulfur dioxide sensor SO2-AE is a sensor based on electrochemical principles. It has the advantages of high sensitivity, high selectivity, resistance to smoke interference, and good low-concentration output linearity. Its measuring range is 0~2000ppm, it has strong adaptability to the working environment (-30~50℃, 15~90%RH), and the resolution is 1.5ppm. It is very suitable for accurate measurement of sulfur dioxide in wine production. Whether in the petrochemical industry, portable sulfur dioxide detectors, or other occasions requiring high-precision sulfur dioxide detection, SO2-AE can provide reliable performance.
In summary, sulfur dioxide plays an irreplaceable role in wine production, but its addition amount must be strictly controlled. The sulfur dioxide distillation instrument and its built-in British Alphasense sulfur dioxide sensor SO2-AE provide winemakers with an effective means to accurately monitor and control sulfur dioxide content, ensuring the quality and safety of wine. With the advancement of science and technology, more high-precision, intelligent sensors and technologies will be used in wine production in the future, promoting the development of the wine industry to higher quality.
