Another natural pH indicator is the spice turmeric. It turns yellow when exposed to acids and reddish brown when in presence of an alkalis.
ANotheR naTUraL ph iNdiCAtOR iS the spIcE TUrMeRic it turnS yEllOw WheN ExpOsed to aciDs And rEdDIsh Brown wHEN in pResencE oF an alkaLIs