Huanlongbing (HLB), also known as citrus greening disease, has been a grave concern for the Florida citrus industry as it imparts off-flavor to citrus products such as orange juice and ultimately leads to death of citrus trees. While limonin and nomilin have been established in previous studies to be responsible for the bitter off-taste, compound(s) that contribute to other off-flavors such as metallic, umami are not known. The objective of this study was to determine what compound(s) give the off-flavor associated with HLB-infected orange juice. Column chromatography was performed on an HLB-infected orange juice and a healthy control sample to separate the water soluble materials from the water insoluble. Sensory taste panel of the water soluble fraction revealed that the HLB sample was less sweet but more sour due to reduced soluble solids and increased titratable acidity. The HLB water insoluble fraction was described as being more bitter, astringent, metallic, grapefruit-like and medicinal. In order to identify the compounds contributing to these off-tastes, the water insoluble fraction was further divided into 54 parts, combined into 24 fractions based on mass spectrometric analysis and freeze dried. Nine of the twenty four fractions were identified to have the HLB off-flavor attributes. Since each fraction contained more than one compound, these nine samples will be further fractionated, tasted and identified by liquid chromatography/mass spectrometry.

Identification of compounds responsible for off flavor in Huanglongbing (HLB) infected orange juice by liquid chromatography/mass spectrometry

248th National Meeting (2014)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.