Question

The major pigments of black grape anthocyanins are _______

• A. Pelargonidin 2-O-rutinoside
• B. Anthocyanidin 3-O-glycosides
• C. Petunidin 3-O-glucoside
• D. Delphinidin 2-O-glucoside

Hint:

In grape skins, malvidin-3-glucoside is the most stable and abundant anthocyanin, playing a key role in the color stability of red and black wines.

Answer 1

The Correct Option is B

Step 1: Understanding the Concept:
Anthocyanins are water-soluble vacuolar pigments that provide the red, purple, and blue colors in many fruits, including grapes.
They consist of an anthocyanidin aglycone bound to one or more sugar moieties.

Step 2: Detailed Explanation:
In black grapes (Vitis vinifera), the primary anthocyanin pigments are mono-glucosides.
These pigments are structurally classified as anthocyanidin 3-O-glycosides (specifically 3-monoglucosides of malvidin, delphinidin, petunidin, cyanidin, and peonidin).
Malvidin 3-O-glucoside is the most abundant pigment responsible for the deep purple-black color of these grapes.
The generalized molecular classification for these major pigments is anthocyanidin 3-O-glycosides.

Step 3: Final Answer:
Therefore, the major pigments of black grape anthocyanins are anthocyanidin 3-O-glycosides.