Abstract:

Konjac glucomannan and chitosan were compounded to make a preservative coating agent for green pepper based on the fact that a film can be formed from them under proper conditions. The preservation effects of proportions of chitosan and konjac glucomannan, amount of added calcium and other factors on fresh green peppers were investigated by single-factor experiments and orthogonal array design. The optimal formula of the coating agent consisted of chitosan 1.5%, konjac glucomannan 0.4%, calcium chloride 2.0%, and glycerin 1% at pH 5.4. When compared with the control samples, the weight loss rate of coated green peppers declined significantly during storage at room temperature, and the hardness and the contents of chlorophyll, soluble solid, organic acid and vitamin C went up, indicating that the coating agent was conducive to prolonging the preservation period of green peppers.

Key words: green pepper, chitosan, konjac glucomannan, preservation