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Metabolomics of headspace gas for diagnosing diseases of fruits and AC Kushalappa,1* A Vikram1 and GSV Raghavan2 1Department of Plant Science, McGill University, Ste. Anne de Bellevue, QC, Canada 2Department of Bioresource Engineering, McGill University, Ste. Anne de Bellevue, QC, Canada Abstract Purpose of review: Metabolomics is a novel biochemical tool for biological studies, including diagnosis of food contaminants and spoilage. It is a non-target approach used to detect, identify and quantify all the metabolites of an organism. With the advent of genomics the need for gene function elucidation has led to the development of chromatographic tools that can now detect hundreds of metabolites in one chromatographic run. In addition, multivariate analysis has enabled classification of spoilage groups involving complex interactions. Postharvest losses of crops, due to spoilage, mainly by microbial contamination, are often very high. Even though metabolites have been used in the identification of food spoilage for a long time, the latest developments in the area of metabolomics are very encouraging for better achieving such a goal. In this paper, the gradual advances made in the use of metabolomics to diagnose spoilage of crops after harvest have been reviewed with comments on directions for future research. Main findings: The metabolomics approach has enabled not only separation of different degrees of food spoilage, but also identification of specific causes of food spoilage. The review reports: 1) what is involved in metabolomics studies; 2) a detailed description of several metabolites or combinations of few metabolites specific to spoilage of different fruits and vegetables; 3) multivariate models to discriminate classes of specific spoilage; 4) the possible application of such a technology to detect and diagnose diseases of postharvest fruits and vegetables under commercial conditions. Directions for future research: Metabolomics is a powerful biochemical tool. However, its full potential has not been exploited to diagnose spoilage of crops after harvest. It can be applied to analyse headspace gases, as well as to characterise the chemical composition of living organisms, which in turn can be used in the diagnosis of food deterioration. The latest advances in the metabolomics technology include sophisticated algorithms and software to automatically deconvolute chromatographic peaks and identify compounds using several databases. Understanding the details of metabolomics analysis is crucial for the efficient use of such a powerful tool to manage crop spoilage after harvest. The directions for the future research needed for the transfer of the metabolomics technology to reduce crop spoilage after harvest, under commercial conditions, are proposed. Keywords: Metabolic profiling; food spoilage; disease detection; postharvest pathology; volatile organic compounds; disease monitoring Stewart Postharvest Review 2008, 2:10 Published online 01 April 2008 doi: 10.2212/spr.2008.2.10 |