Submitted to: Book Chapter
Publication Type: Book / Chapter
Publication Acceptance Date: December 22, 1998
Publication Date: N/A
Interpretive Summary: With the improvement of storage technology, it is now possible to keep apples in an intact condition long after harvest. In general apples suffer, however, from a loss of flavor, which depends on the condition of storage. This problem is further compounded when apples are, for the sake of the convenience and fresh-like quality, fresh-cut or minimally processed (F- c/M-p) for consumers. These F-c/M-p products readily deteriorate in quality, especially color and texture, as a result of endogenous enzymes, enhanced respiration, and microorganisms which lead to reduced shelf-life. Since F-c/M-p fruits and vegetables are increasing their market-share, we wanted to see if the developed technology of conducting polymers, known as electronic-noses or E-nose, would be a valuable tool to rapidly assess the quality of F-c/M-p apples. We also examined the instrument's ability to distinguish among different varieties of apples such as Red Delicious and Granny Smith. Analysis of the data indicated that the instrument and its associated software were able to distinguish between the two apple varieties. Furthermore, the E-nose was able to distinguish storage- differences between whole apples and between stored and treated F-c/M-p apples. These data suggest that continued development of the electronic nose technology should lead to technology that will permit processors to have a rapid method to assess the quality of their product thereby permitting production of high quality F-c/M-p apples for consumer.
Technical Abstract: Within the last 5 years there has been a major surge in the development of electronic nose technology (conducting polymers and metal oxide sensors). These multisensor electronic nose (E-nose) devices are coupled to statistical data processing packages designed to simulate the way the human brain interprets or processes the interaction of multiple sensory inputs. Fortunately, to be able to develop an electronic instrument that, in the broadest sense of the word, mimics the human olfactory system, it is not necessary to understand exactly how the human brain interprets complex vapors. E-nose technology has encouraged a wide dissemination of this instrumentation within the food and fragrance industries where it is now used primarily for quality control. Analysis time using an E-nose is often only a few minutes making it a viable alternative to longer classical gas chromatographic (GC) techniques. The fruit component of fresh-cut produce is the fastest growing market in today's produce business, representing a value-added, ready-to-use commodity that satisfies consumer requirements for authentic flavor, texture, nutritional value, and safety. These requirements challenge the packager/producer to develop cost effective ways of producing and monitoring their products for the presence of spoilage and/or pathogenic microflora and to stabilize and maintain their product's flavor. Therefore, we developed an E-nose method to distinguish differences in and keeping-quality of whole, fresh-cut, and minimally processed Gala variety apple using a 32 sensor (AromaScan A32/50S multisampler).