33G-24 |
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U. SCHWEIGGERT1, T. Stoll, A. Schieber1, and R. Carle. (1) Institute of Food Technology, Hohenheim University, August-von-Hartmann-Strasse 3, Stuttgart, 70599, Germany Due to the low yields associated with carrot juice production, approximately one third of the raw material remains as pomace which is mainly disposed as feed or fertilizer. However, carrot pomace contains large amounts of valuable compounds such as carotenes and dietary fiber. Furthermore, degradation products of pectin (oligogalacturonic acids, OGAs) have been reported to inhibit bacterial adherence to epithelial cells and show potential for the treatment of infectious diseases. The objective of our study was to develop a process for the complete utilization of carrot pomace as a source of carotenes and OGAs. The process was developed on pilot plant scale and included techniques of fine grinding, enzymatic hydrolysis, finishing, homogenization, and concentration. Optimal degradation of the carrot matrix was achieved at 50 °C within one hour using pectolytic and cellulolytic enzymes (1,500 mg/kg, pH 4). The hydrolyzate was used for the production of a functional beverage based on cloudy apple juice. The product obtained after moderate concentration contained 64 mg/kg carotenes (at 3.8 °Bx). Carotene stability in the model beverage proved to be excellent during 24 weeks of storage. Even under intense illumination neither degradation nor trans-cis-isomerization were observed. Also cloud stability, as determined by centrifugation and real time sedimentation tests, turned out to be satisfactory. Modification of enzymatic hydrolysis led to the formation of OGAs preferably with a degree of polymerization of 2 and 3 which reportedly possess maximum bioactivity. The results demonstrate that carrot pomace represents a yet underestimated by-product which should be exploited for the recovery of functional compounds. Due to the presence of carotenes, the hydrolyzate may be used for coloring purposes or as a functional food ingredient, thus replacing synthetic b-carotene formulations. In addition, antimicrobial OGAs produced by enzymatic hydrolysis of carrot pectin might be used for therapeutic purposes.
Session 33G, Nutraceuticals & Functional Foods: Lipid and probiotic functional foods
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