Sucrose, is an organic chemical compound, a disaccharide composed of glucose and fructose, the common sugar, 

For more information on Sucrose as a food: 

Sugar

What it is used for and where

Cosmetics

It is used in cosmetics as a humectant and moisturiser. Its action on the skin is slightly cleansing and eliminates those spurious components that can clog pores, improving the general tone of the epidermis.

Flavoring agent. The purpose of this ingredient is to modify the solution to add flavour. Natural flavouring extracts are rather expensive, so the cosmetic and pharmaceutical industries resort to synthesised substances that have sensory characteristics mostly similar to natural flavourings or are naturally equivalent. This ingredient is isolated through chemical processes or is synthesised from chemicals.

Skin conditioning agent -  Humectant. Humectants are hygroscopic substances used to minimise water loss in the skin and to prevent it from drying out by facilitating faster and greater absorption of water into the stratum corneum of the epidermis. The epidermis is the most superficial of the three layers that make up the human skin (epidermis, dermis and hypodermis) and is the layer that maintains hydration in all three layers. In turn, the epidermis is composed of five layers: corneum, the most superficial, lucidum, granulosum, spinosum and basale. Humectants have the ability to retain in the stratum corneum the water they attract from the air and have the function of moisturising the skin. It is better to use them before emollients that are oil-based.

CAS   57-50-1