Sauvignon grape vs vinifera

Sauvignon grape and vinifera both are nouns.

Word	Noun	Adjective	Verb	Adverb
Sauvignon grape	Yes	No	No	No
vinifera	Yes	No	No	No

As nouns, vinifera is a hypernym of Sauvignon grape; that is, vinifera is a word with a broader meaning than Sauvignon grape:

Sauvignon grape: small blue-black grape of Medoc region of France highly prized in winemaking
vinifera: common European grape cultivated in many varieties; chief source of Old World wine and table grapes

Other hypernyms of Sauvignon grape include common grape vine, vinifera grape, Vitis vinifera.

Sauvignon grape (noun)	vinifera (noun)
small blue-black grape of Medoc region of France highly prized in winemaking	common European grape cultivated in many varieties; chief source of Old World wine and table grapes