If we take food rich in lime juice, then
(1) Action of ptyalin on starch is enhanced.
(2) Action of ptyalin on starch is reduced.
(3) Action of ptyalin on starch is unaffected.
(4) Action of ptyalin on starch stops.
Please find below the solution to the asked query
Option (2) is correct.
The pH of mouth is slightly acidic to neutral (6.5-7.0). Ptyalin acts best in this range of pH. Lime juice contains mild acid and so, decrease the pH of mouth, thereby reducing the action of ptyalin on starch in the mouth.
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