The Compendium of Kāśyapa 8.6.71.p1

8.6.71.p1

pūrvaḥ pūrvaḥ parairyukto dvikaḥ te pañcadaśa bhavanti | tatra madhuraḥ pañcabhiramlādibhiryujyate | tadyathā--madhurāmlaḥ madhuralavaṇaḥ madhurakaṭukaḥ

Each preceding one combined with succeeding ones forms pairs; they are fifteen. There, sweet is combined with five, beginning with sour. That is to say: sweet-sour, sweet-salt, sweet-pungent,