No abstract

Proteins such as keratin, lactalbumin, and gluten can be obtained from agricultural sources. These proteins contain the amino acid cysteine. Cysteine allows for the formation of inter- and intramolecular sulfur-sulfur bonds. It was found that cysteine-containing proteins have varied properties and can be blended together to form materials with the attributes of each polymer. The addition of wheat gluten to other proteins increases the strain to break or "toughness". The addition of lactalbumin increases the modulus and strength of blends. Birefringence shows that lactalbumin contains an added "structure" not found in the other proteins. Permeability studies reveal that one protein may dominate the transport of small molecules through the blend. Scanning electron microscopy shows that blends contain features of each protein and correlate with observed tensile properties.

Four formulations of whey-protein-isolate (WPI) coatings were used to coat chocolate-covered almonds. Two formulations were without lipid and two were with lipid. The 2 WPI formulations without lipid varied in native-as compared with the heat-denatured WPI amount. The 2 WPI formulations with lipid varied in the lipid amount. The shellac formulation consisted of 30% solids, of which 90% was shellac and 10% was propylene glycol. A central location consumer test was carried out for attributes such as overall degree of liking. The results strongly indicate that water-based WPI-lipid coatings can be used as an alternative glaze, with higher consumer acceptance than alcohol-based shellac.