Multivariate investigation of physicochemical, nutritional and sensory attributes of traditional Lebanese grape molasses

Abstract

AbstractGrape molasses is a natural sweetener widely consumed in Lebanon and Eastern Mediterranean countries. However, the lack of national standards that control its production often leads to inconsistent products and complicates international exports. Thirty grape molasses samples were collected from different Lebanese regions, and their physicochemical, microbiological, and sensory properties were investigated using a multivariate approach. Significant disparities were detected among samples obtained using different processes and from different geographical origins. The samples from the Bekaa region, manufactured with semi-industrial heat exchangers, were the most appreciated by the panelists due to their high dry matter content (80.41%), Brix degree (75°Brix), low water activity (0.55) and low titratable acidity (0.30%). Microbial contamination with osmophilic microorganisms was detected in several samples, highlighting poor hygiene practices and factory sanitation, in addition to post-contamination during the packaging and whipping steps. In summary, the key parameters that affect grape molasses quality are geographical origin, grape variety and ripening stage, soil and climatic factors, and manufacturing process, particularly juice concentration technique/time. These factors should be considered for future optimization and standardization of production processes and for monitoring and homogenizing the quality of this product.