Effect of size grading on the aroma discrimination of fresh and milled ginger by an electronic nose

Fresh ginger rhizomes graded according to three commonly occurring thicknesses, big (above 2.5cm), medium (2.0-2.5cm) and small (0.5-2.0) as well as their milled powders were subjected to aroma discrimination by sensory evaluation and an Electronic nose in order to identify possible headspace aromatic differences, among the three ginger grades. Principal component analysis (PCA) maps of the data showed that the electronic nosesuccessfully discriminated the aroma or volatile compounds of the three ginger grades in different clusters for each group, suggesting that they vary in chemical composition. Contrary to expectations, the flavour variations of the three ginger grades could not be detected by the human nose It is evident from this study that the electronic nose is a very effective and fast tool todifferentiate aroma of various ginger grades and could easily assist its growers, buyers, processors as well as product developers in effective distribution and utilization.Keywords: Electronic nose, principal component analysis, aroma discrimination, grading, sensory evaluation, ginge