At a conference, the speaker's grand finale was sautéing mealworms (insect larvae) in butter and serving them to the audience. They were crunchy (like popcorn hulls) because their exoskeletons contain the polysaccharide .

Chitin

Explanation:

Chitin is the polysaccharide that makes up the outer exoskeleton of many insects. It is a fibrous polymer, that is made up of chains of modified glucose molecules. It  is comparable in structure to cellulose, which makes up the plant cell wall. In function, it is more similar to keratin or collagen, although these are proteins.

Chitin is exclusively found in the arthropods, mollusks and fungi. It plays an important protective and structural role, giving organisms their tough outer exoskeleton or strong cell wall in the case of fungi.