The Compendium of Caraka 8.12.7

8.12.7

snigdhāmlasvāduhṛdyāni tato 'amlalavaṇau rasau/
svādutiktau tato bhūyaḥ kaṣāyakaṭukau tataḥ//

Then with items that are unctuous, sour, sweet, and pleasing to the heart; then with sour and salty tastes; / then again with sweet and bitter, and then with astringent and pungent tastes.