Altering the water holding capacity of potato pulp via structural modifications of the pectic polysaccharides

Abstract

Potato pulp is a low value agricultural side stream with great valorisation potential as prebiotic food ingredient. An interesting functionality different from other prebiotics is its high water holding capacity (WHC). This study aims at exploring the relationship between physical and enzymatic modifications in the potato pulp and its WHC. Different temperature treatments and storage conditions were found to have a great influence on the WHC, freezing decreasing the WHC the least (15%) compared to fresh pulp. Ultrasonication of frozen pulp increased its WHC by 32%, while it did not have an effect on fresh pulp. Of the various tested enzymes, only protease led to an increase in WHC of fresh pulp (by 48%). The WHC of frozen and dry pulp could not be positively influenced by enzymatic treatment. Structurally, the potato pulps with increased WHC exhibited a larger surface area and more flaky structure.

Keywords

• Potato pulp
• Water holding capacity
• Storage method
• Enzymatic modification
• Ultrasonication