Objective evaluation of chilled pork color by digital image and stepwise regression

To develop accurate and rapid method for objective evaluation, the effect of digital image processing and stepwise regression on chilled pork color evaluation were studied. Pork carcass longissimus dorsi muscles were cut at 3～4th rib and bloomed for 60min. Digital images of the muscle surface were captured by digital camera and processed to extract image color features(L*, a*, b*, Chroma, Hue angle). Extracted color features from 80 carcass longissimus dorsi muscles were used to establish color score evaluation model by stepwise regression . The results showed the color score evaluation model by stepwise regression based on color features from digital image processing was better than that by BP artificial neural network and the evaluation accuracy was 78.8% and 60.4%, respectively if judged by the formula∣evaluation color score-sensory color score∣≤0.3. The former had no significant variation with evaluation accuracy(78.2%) compared with the best single panelist (P＞0.05). Therefore, digital image processing is an effective tool for objective evaluation of chilled pork color.