Barley Malt Esterification after Ultrasound and Stearic Acid Treatment: Characterization and Use as Stabilizing Agent in Oil-in-Water Emulsions

This work aimed to obtain novel materials from malt modification for using in oil/water emulsions. Malt was modified using stearic acid (2% w/w) in combination with different energy densities (33.8 x 10(6), 60 x 10(6), 72.5 x 10(6), and 107.5 x 10(6) J/m(3)) from ultrasound probe resulting in four materials. These materials were characterized by degree of substitution (DS), amylose content, dextrose equivalent (DE), protein content, solubility, thermal properties, Fourier-transform infrared spectroscopy (FT-IR), crystallinity analysis by X-ray diffraction, and scanning electron microscopy. Emulsions containing 15% total solids (25% canola oil and 75% modified malt as stabilizing agent) were prepared and characterized. Results showed that increasing energy densities produced different effects on malt properties due to an increase in DS, amylose content, and DE values. The sonication process in combination with stearic acid increased malt solubility and the gelatinization temperature of malt, caused modifications of starch crystallinity in the amorphous region and hydrolysis of starch granules, and promoted good stabilizing properties for emulsions containing modified malt.

Automated summary

The study aimed to obtain novel materials for oil/water emulsions from malt modification using stearic acid and different energy densities from ultrasound probe. Increasing energy densities affected malt properties by increasing degree of substitution, amylose content, and dextrose equivalent values. The sonication process with stearic acid enhanced malt solubility, gelatinization temperature, and stabilizing properties for emulsions.