Structural Characterization of a Hua Tuber Polysaccharide and Its Contribution to Moisture Retention and Moisture-Proofing of Porous Carbohydrate Material.

Porous carbohydrate materials such as tobacco shreds readily absorb moisture and become damp during processing, storage, and consumption (smoking). Traditional humectants have the ability of moisture retention but moisture-proofing is poor. Hua polysaccharide (PCP 85-1-1) was separated by fractional precipitation and was purified by anion exchange and gel permeation chromatography. The average molecular weight (Mw) of PCP 85-1-1 was 2.88 × 10 Da. The monosaccharide composition implied that PCP 85-1-1 consisted of fucose, glucose, and fructose, and the molar ratio was 22.73:33.63:43.65. When 2% PCP 85-1-1 was added to tobacco shreds, the ability of moisture retention and moisture-proofing were significantly enhanced. The moisture retention index (MRI) and moisture-proofing index (MPI) increased from 1.95 and 1.67 to 2.11 and 2.14, respectively. Additionally, the effects of PCP 85-1-1 on the aroma and taste of tobacco shreds were evaluated by electronic tongue and gas chromatography-mass spectrometry (GC-MS). These results indicated that PCP 85-1-1 had the characteristics of preventing water absorption under high relative humidity and moisturizing under dry conditions. The problem that traditional humectants are poorly moisture-proof was solved. PCP 85-1-1 can be utilized as a natural humectant on porous carbohydrates, which provides a reference for its development and utilization.