A Distance Based Freshness Evaluation Method for Oyster Monitoring by Electronic Nose

Oysters have high nutritional value and will rapidly inactivated when they leave their native environment, which makes the detection and evaluation of oyster freshness value much. To make the oyster monitoring noninvasive, a distance-based freshness evaluation method by electronic nose is proposed. Oyster samples of different degrees of freshness at storage conditions were tested for 8 consecutive days using a laboratory-developed electronic nose. Features were extracted and downscaled by Principal Component Analysis (PCA). Taking the sample of day 1 as the base, the Euclidean distance between the samples of following days and the base was proposed as the degree of deviation of freshness. Results prove the method interesting to evaluate the oyster freshness noninvasive.