Development of a thin layer chromatography-based method to detect sorbitol presence in milk and its applicability in formalin preserved milk samples.

Sorbitol has been the new and emerging adulterant in dairy industry. The main aim of the study was to develop a method to detect sorbitol in milk, which is not affected by other sugars, polyols and formalin. Hence, a thin layer chromatographic (TLC) method was standardized to detect the sorbitol in milk. In the study 90 s duration for the impregnation of Silica gel 60F TLC plates with Cu- ions was found suitable to resolve sorbitol as a distinct spot. The standardized conditions were (1) developing solvent system consisting of n-propanol: ethyl acetate: water (7:1:2), (2) 0.5% of potassium permanganate in 0.1 M NaOH as color developing reagent. (3) Drying temperature (65°C/ 10 min.) after spraying the color developing reagent. The limit of detection was 0.2% of added sorbitol in milk. The standardized method could also detect the sorbitol in the presence of sucrose, glucose and polyols like mannitol and maltitol. In both cow and buffalo milk samples the standardized methodology performed well in detection of sorbitol. The method also performed well in sorbitol spiked formalin preserved milk samples. This method can be an alternative to the other methods involving costly equipment in detecting adulteration of milk with sorbitol.

© Association of Food Scientists & Technologists (India) 2023. Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.

Conflict of interestThe authors have neither any conflicts of interest nor competing interest to declare.