Alkalinity is mainly caused by calcium carbonate and bicarbonate. It causes high pH values throughout the brewing process. Hydrogen ions are removed from solution, thus wort pH remains high which can result in low extract yield; the presence of undesirable protein components; worts and beers more prone to infection; an increased extraction of silicates, polyphenols and tannins during sparge, which can result in harsh “after tastes” in the finished beer.
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