ARS | Publication request: COMPARISON OF HEADSPACE GC AND ELECTRONIC SENSOR TECHNIQUES FOR CLASSIFICATION OF PROCESSED ORANGE JUICES

Submitted to: Lebensmittel Wissenschaft und Technologie
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: February 14, 2000
Publication Date: August 21, 2000

Interpretive Summary: An electronic nose is a device using a group of electronic sensors placed directly above a food or juice product which "sniffs" the sample, such as orange juice, and determines something about its quality based on the vapors emitting from the product. We compared the ability of an electronic nose to evaluate orange juice samples with the ability of a commonly used chromatographic instrument to do the same thing. Both devices were able t separate different types of orange juice into separate groups, including fresh squeezed juice, pasteurized not from concentrate and frozen concentrated orange juice. These methods are useful for monitoring quality of different products and they can take the place of sensory panels in many cases. An electronic nose makes a more rapid determination of quality than the more traditional chromatographic instruments, but is not quite as selective in separating juice types into clearly-defined groups.

Technical Abstract: Three types of commercial orange juice samples, pasteurized not from concentrate, frozen concentrate, and single strength juice reconstituted from concentrate, were classified by discriminant analysis using quantities of 25 volatile juice constituents determined by headspace gas chromatography (HSGC). An electronic sensor instrument was also used to evaluate and classify the same juice samples, and the results were compare to those obtained by HSGC. Two sets of samples were classified by HSGC analysis into the three juice types. The electronic sensor instrument classified the first set into three types, but was less successful in classification of the second larger set of samples. The two analytical techniques were complementary since they afforded somewhat different separation patterns.