Ex situ volatile survey of ground almond and pistachio hulls for emission of spiroketals: Analysis of hull fatty acid composition, water content, and water activity

- Analysis of ground almond hull and shell emissions detected the spiroketals conophthorin and chalcogran.
- Conophthorin is an important semiochemical of the insect pest navel orangeworm.
- The spiroketals appear to be produced by damaged hull tissue.
- The fatty acid composition, water activity, and water content of developing almond and pistachio hulls were determined.