Microbial volatile organic compounds and their application in microorganism identification in foodstuff

•The MVOCs as indicators produced from different foodstuff were reviewed.•The sampling techniques for MVOCs from foodstuff were summarized.•The analytical methods for MVOCs from foodstuff were reviewed.•The approaches for identification of microbial genera by MVOCs were expounded.•The problems in the microorganism identification via MVOCs and future trends were explored.

Foodborne diseases encompass a wide spectrum of illnesses and are an emerging public health concern worldwide. The contamination of food with microorganisms may occur at any stage in the process from food production to consumption. Multi-organ failure and even cancer may result from the ingestion of microorganism-contaminated foodstuffs, representing a considerable burden of disability as well as mortality. Thus, fast and effective approaches for evaluation of microbial contamination in foodstuff are vital. In recent years, the microbial volatile organic compounds (MVOCs), as indicators of microbial contamination, have already been playing an important role in clinic diagnosis and environment monitoring, and they have gradually being used to evaluate the microbial contamination in foodstuff. The microbial volatile organic compounds are a variety of volatile compounds produced by fungi, molds and bacteria during metabolism. By far, more than 1000 organic compounds have been identified as MVOCs comprised of alcohols, aldehydes, hydrocarbons, acids, ethers, esters, ketones, terpenoids, sulfur and nitrogen compounds. It is difficult to make reliable lists of MVOCs for relevant microbial species, since different microorganisms could share the same MVOCs. Although none of them can be considered to be exclusive or specific for certain microbial species, the identification of microbial species can be performed by statistical analysis of the MVOCs profiles. In addition, the approach based on enzyme-generated MVOCs specific to certain microbial species has also been applied in identification of microbial flora. In this paper, we summarize MVOCs in foodstuff and their application in food safety inspection. Moreover, the most commonly used analytical methods for detection of MVOCs are introduced as well. Additionally, the use of the approaches in the identification of microbial species is also expounded in this review.