Garudapurana 1.173.7

1.173.7

dadhi takraṃ kāñjikaṃ ca lakucaṃ cāmlave tasam /
amlo loṇaḥ śuṇṭhīyukto jāraṇaḥ pācano rasaḥ //

curd, buttermilk, fermented gruel, lakuca, and amlavetasa— / the sour taste, combined with salt and dry ginger, is a digester and promoter of digestion;