Oligosaccharides gentiobiose

Fourteen DFAs and some oligomers were identified in caramel obtained by thermal treatment of inufin. - Monosaccharides (glucose, fructose), dehydration products (1,6-anhydro-p-D-glucopyranose, 1,6-anhydro-p-D-glucofuranose), disaccharides (gentiobiose and isomaltose), and oligosaccharides were also found in glucose and sucrose caramel. ... 

Fig. 1.—Molecular-rotation relationships of several raffinose-type oligosaccharides. Me, methyl a-D-galactopy ranoside Gl, D-glucose Mb, melibiose Mt, manninotriose Vt, verbascotetraose S, D-glucitol M, melibiitol Ml, manninotriitol Su, sucrose K, raffinose St, stachyose V, verbascose Gb, gentiobiose Ge, gentianose.

Taste sweetness is the most characteristic property of soluble sugars. Sucrose is the reference substance for sweet taste fructose is sweeter and glucose is less sweet than sucrose. There are some exceptions like gentiobiose which has bitter taste. Sweetness decreases when molecular weight increases, and the higher oligosaccharides are tasteless (Table 7.1). Polyalcohols also have sweet taste. 

Gentiobiose and cellobiose are the only oligosaccharides (occurring in the cardiac glycosides) which have been synthesized. 

Oligosaccharides in combination with phenols may also be removed intact by careful hydrolysis with acid. Thus, when rutin is heated with 10% aqueous acetic acid, it yields rutinose. Dilute mineral acids can, for example, be used for the removal of sophorose from kaempferol 3-sophoroside, " and of gentiobiose from p-hydroxyphenyl 9-gentiobio-side. A comparison of the use of formic acid-cyclohexanol and hydrochloric acid-acetic acid for the partial hydrolysis of glycosides has been made by Chandler and Harper. There appears to be no general rule governing the use of these acids. 

Glycosidic bonds between monosaccharides give rise to oligosaccharides and polysaccharides. The simplest oligosaccharides, the disaccharides, include compounds such as sucrose and lactose, which are referred to as sugars (like the monosaccharides). Other common disaccharides include trehalose, maltose, gentiobiose, and cellobiose. 

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