טכניון מכון טכנולוגי לישראל
הטכניון מכון טכנולוגי לישראל - בית הספר ללימודי מוסמכים  
M.Sc Thesis
M.Sc StudentAdes-Waksman Hagar
SubjectV-Amylose Inclusion Complexes as a Controlled Release System
of Cyclic Aroma Compounds
DepartmentDepartment of Biotechnology
Supervisor Dr. Eyal Shimoni
Full Thesis textFull thesis text - English Version


Abstract

Flavors are of major importance for food acceptability by the consumers. A well known problem of the food industry is the fast loss of aroma which reduces the shelf life of many products. The overall goal of this research was to examine the platform of starch based inclusion complexes for the oral release of aroma substances by salivary fluids. Inclusion of flavors in starch complexes can control retention and release of flavor compounds. Another issue was the influence of the flavor compound and the starch type on complexation. Menthone, menthol and limonene were used as model flavor compounds. All have similar isopropyl methyl-chyclohexane structure but different functional group and properties respectively. Starches with different amylose content were used for complexation; amylose, high amylose corn starch (HACS), corn starch and waxy starch. The complexes were characterized by x-ray diffraction (XRD) and inclusion ability. The complexes were further characterized using fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), dynamic light scattering (DLS) and atomic force microscopy (AFM). Aroma retention by the complex was tested under pH, temperature and storage challenges. Furthermore, the kinetic of aroma release in simulated saliva fluids (SSF) was tested as well. The results of the presented research show that both menthone and menthol are able to form V-amylose complexes in a food grade process, based on acidification of alkali solution. Limonene did not form inclusion complexes probably due to high volatility and/or low solubility. As for the effect of amylose content in the starch; as the amylose content increased the yield was higher and the quality of the complex was better, with more aroma included and less free core content. The complexes had melting temperature of over 90oC which makes them suitable for heat treatment as pasteurization. The weibull kinetic model was used to describe the kinetics of aroma release. The results show the potential of starch-aroma complexes to retain aroma and release it in the oral cavity.