Sulfites in beer: reviewing regulation, analysis and role

Abstract

Beer is an extremely complex mixture of more than 3,000 different compounds in an aqueous environment. Thus, it is perhaps not surprising that the maintenance of beer quality throughout its lifetime has been a considerable challenge for brewers. Whilst it is inevitable that chemical changes will occur in beer with the passage of time, it is the formation of flavor-active components which is of immediate concern to an overview of beer shelf life stability. Sulfur dioxide has long been recognized by brewers as the most important factor in delaying flavor staling, and prolonging the shelf life of beer. However, nowadays, sulfur dioxide and sulfites are considered allergens and concerns about the safety of their use as food additives have been on the increase. The present review is structured into three main parts. Firstly, the chemical properties of sulfur dioxide are presented, along with the toxic effects and maximum legal levels permitted according to U.S. and EU legislation. As the accurate determination of the free, bound and total sulfur dioxide in beer is essential to ensuring regulatory compliance, several methods have been developed for analyzing sulfur dioxide in beer. Thus, secondly, various types of methods are reported and compared with the officially recommended ones. Finally, the crucial role of sulfite in the control of flavor instability of beer is discussed in light of the current data. Two courses of action have been proposed, which are elucidated in detail relating firstly to the fact that sulfite inhibits beer oxidation during storage by acting as an antioxidant and, secondly, sulfite reacts with the carbonyl staling compounds in beer, and thereby masks stale flavors.

Impact of Wort Amino Acids on Beer Flavour: A Review

“…The yeast strain and the brewing conditions produce different amounts of sulfite compounds. Brewers can produce a beer with a sulfite content under 10 mg L −1 , the level at which the declaration of sulfites has been mandated for the labelling of alcoholic beverages by EU and US legislation [53]. The flavour threshold of SO 2 in beer is high (25 ppm), and binding to carbonyls groups generally keeps the free SO 2 well under the sensory threshold.…”

Proses untuk Menurunkan Konsentrasi Sianida Bebas dalam Air Limbah Pertambangan Emas Skala Kecil

“…Spesi gas sulfur (SO 2 ) di dalam air akan berkesetimbangan dengan hidrogen sulfit dan bisulfit tergantung dari pH lingkungan. Pada pH di bawah 2 spesi yang dominan adalah SO 2 , pada pH antara 2,5-6,5 spesi yang dominan adalah hidrogen sulfit dan spesi bisulfit dominan pada pH di atas 8,5 (17) .…”

Development and validation of a glass-silicon microdroplet-based system to measure sulfite concentrations in beverages

“…However, concerns about the safety of sulfite have recently increased as it may cause respiratory problems or migraine in sulfite-sensitive patients [ 1 ]. For this reason, food products with sulfite levels exceeding 10 mg L −1 must be labeled with the statement “contains sulfites” [ 2 ]. A sensitive, accurate, and rapid analysis method to measure sulfite levels in fermented beverages is therefore desirable.…”

“…A sensitive, accurate, and rapid analysis method to measure sulfite levels in fermented beverages is therefore desirable. While several methods to measure sulfites are available, including the Monier-Williams method, combining distillation and titration [ 3 ], gas chromatography [ 4 ], HPLC [ 3 ], ion exchange chromatography, amperometry [ 1 ], fluorescent probes [ 5 ], enzymatic methods [ 6 ], and colorimetry [ 7 ], many of these are time-consuming, require costly equipment, and the results can in some cases even be unreliable [ 2 , 3 ]. One technique that can overcome the limitations posed by the currently applied methods is droplet microfluidics.…”