Starch-Flavor Complexation Applied to 2-Acetyl-1-pyrroline.

The pleasant popcorn-like smelling compound 2-acetyl-1-pyrroline (2AP) occurs naturally in many foods but is scarcely used as a flavoring agent due to its great instability. In this work, we evaluate the potential of high amylose corn starch to complex and stabilize 2AP. The methodology was first optimized using model compounds, 2-acetylpyridine and 2-acetyl-2-thiazoline, and then applied to 2AP. Complexes were successfully prepared and characterized using X-ray diffraction, gas chromatography, and differential scanning calorimetry. Loadings of up to 0.504 (±0.071)% 2AP were achieved, and storage studies showed that over half of the flavor was retained after 2 weeks at 0% relative humidity. To our knowledge, this is the first demonstration that 2AP can form amylose inclusion complexes and may lead to a method to effectively stabilize this labile aroma compound.

Formation of inclusion complexes between high amylose starch and octadecyl ferulate via steam jet cooking.

Amylose-ligand inclusion complexes represent an interesting approach to deliver bioactive molecules. However, ferulic acid has been shown not to form single helical inclusion complexes with amylose from high amylose maize starch. To overcome this problem a lipophilic ferulic acid ester, octadecyl ferulate, was prepared and complexed with amylose via excess steam jet cooking. Jet-cooking octadecyl ferulate and high amylose starch gave an amylose-octadecyl ferulate inclusion complex in 51.0% isolated yield. X-ray diffraction (XRD) and differential scanning calorimetry (DSC) confirmed that a 61 V-type inclusion complex was formed. Amylose and extraction assays showed the complex to be enriched in amylose (91.9±4.3%) and contain 70.6±5.6mgg(-1) octadecyl ferulate, although, minor hydrolysis (∼4%) of the octadecyl ferulate was observed under the excess steam jet-cooking conditions utilized. This study demonstrates that steam jet cooking is a rapid and scalable process in which to prepare amylose-octadecyl ferulate inclusion complexes.