Beer Colloid: Studies with Model Systems¹

1 Presented at the 44th Annual Meeting, Toronto, Canada, May 1978.

Abstract

Formation of haze in beer is the result of instability of the beer colloid; molecules or minute particles react and aggregate to form the visible particles of haze. Certain model systems, consisting of protein-carbohydrate (eg, papain-propylene glycol alginate), also form hazes with characteristics of pH, concentration, and salt tolerance similar to those of chill haze. When beer is used as a solvent for such models, the haze formed is much less than in an aqueous system or even absent. Iron (Fe⁺⁺⁺) also induces haze in beer but this haze is greater when the beer is diluted and less when propylene glycol alginate is added. Oxygen-induced haze is also inhibited by propylene glycol alginate. These observations suggest that beer contains an inherent haze-preventing factor that may be protein-carbohydrate in character; such a compound could be formed during, for example, kettle boiling. This suggests that although beer can be successfully stabilized by traditional treatments that remove or digest the haze-forming reactants, enhancement of inherent haze stability during processing may be a desirable aid to beer stabilization.

• Alginates
• Beer
• Colloid
• Haze
• Papain
• Propylene glycol alginate