Portable electronic nose for detection of spoiling Alaska pink salmon (Oncorhynchus gorbuscha)

The ability of a portable hand-held electronic nose (EN) in detecting spoilage of whole Alaska pink salmon (Oncorhynchus gorbuscha) stored at 14 degrees C and in slush ice (1 degrees C) was investigated. Fish were sampled daily at 14 degrees C for up to 3 d, while fish stored in slush ice were sampled at various intervals up to 16 d. Sensory evaluations indicated that fish were rejected at day 3 when stored at 14 degrees C and at day 12 when stored in slush ice. Aerobic bacteria counts for fish skin at 14 degrees C ranged from 3.4 log(10) colony-forming units (CFU)/cm(2) (day 0) to 4.8 log(10) CFU/cm(2) (day 3) and for fish stored in slush ice ranged from 3.4 log(10) CFU/cm(2) (day 0) to 5.5 log(10) CFU/cm(2) (day 16). The correct classification rate using forward stepwise general discriminate analysis was 85% and 92% for EN analysis of belly cavity volatiles for fish held at 14 degrees C and in slush ice, respectively. A predictive model may be developed for spoilage of whole Alaska pink salmon by analyzing belly cavity odors using the EN.