Characterization of lactobionic acid evidencing its potential for food industry application

Abstract The chemical configuration of the lactobionic acid (LBA) evidences its potential properties, among which the antioxidant, antimicrobial, and chelating activities stand out in the literature. However, few studies aim at testing and confirming them. The purpose of this study was to determine some selected LBA properties, whose characteristics are of interest for its use as an ingredient in foodstuffs. The discussion followed the results of Fourier‐Transform Infrared Spectroscopy (FTIR), X‐ray diffractometry (XRD), 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH) radical, 2,2′‐azino‐bis(3‐ethylbenzothiazoline‐6‐sulphonic acid) (ABTS) radical, thermogravimetric/derivative thermogravimetry (TGA/DTG), minimal inhibitory concentration (MIC) by the diffusion disk test, scanning electron microscopy (SEM), and iron/calcium chelating methodologies. The XRD analysis revealed the presence of an amorphous halo and the absence of defined peaks, a fact possibly related to its high hygroscopicity. The FTIR showed characteristic bands of the LBA structure. Results from TGA/DG verified the LBA thermal degradation, which evidenced that LBA could participate in most food industry unit processes within the first mass loss event. Antioxidant capacity reached a maximum inhibition of 56% for LBA and the chelating capacity of the iron ion achieved 54% of chelated ions, while the calcium ions reached 15%. The results revealed high potential of LBA application for microbial inhibition, moisture retention, and texture maintenance throughout storage of food products. Practical Applications Despite the potential of application of the LBA, few quantitative results demonstrate its ability of action in food. Even without permission in most countries around the world, more research with LBA will encourage the investigation of its toxicology, expanding the areas of application. Its thermal degradation profile and elevated solubility demonstrated the potential of LBA as food ingredient, performing moreover as antioxidant, chelating agent, antimicrobial, and texturizer. The results open the possibilities for many applications in the field of food chemistry and food industry.