The Compendium of Caraka 1.26.40_1

1.26.40_1

evameṣāṃ rasānāṃ ṣaṭtvamupapannaṃ nyūnātirekaviśeṣānmahābhūyānāṃ bhūyānāmiva sthāvarajaṅgamānāṃ nānāvarṇākṛtiviśeṣāḥ ṣaḍṛtukatvācca kālasyopapanno mahābhūtānāṃ nyūnātirekaviśeṣaḥ //

Thus the sixfold nature of these tastes is established through the specific deficiency and excess of the great elements, just as the various distinctions of color and form among inanimate and animate beings [are established]; and the specific deficiency and excess of the great elements is established because time has six seasons.