Microbiology of food taints

Abstract

Fresh and processed foods are often spoilt by the presence of undesirable flavours and odours caused by microbial action. The aim of this paper is to review the current knowledge of microbiologically induced taints that occur in a wide range of foodstuffs, including meats, poultry, fish, crustaceans, milk, dairy products, fruits, vegetables, cereals and cereal products. Examples have been chosen where the compounds responsible for the taint have been identified and sufficient data obtained to demonstrate the involvement of microorganisms. However, in some cases the full identity of the causative organism may not have been elucidated. The types of microorganisms covered by this review include bacteria, fungi, yeasts, actinomycetes and cyanobacteria. Although cyanobacteria do not in general infect foods, their presence in aqueous systems and water supplies can lead to off‐flavours in aquatic organisms and processed foodstuffs. Several examples of each of these processes are discussed. Wherever possible, the likely biosynthetic pathway used by the microorganism to produce the offending compound in a foodstuff is indicated.

Simultaneous Analysis of Guaiacol and Vanillin in a Vanilla Extract by Using High-Performance Liquid Chromatography with Electrochemical Detection

“…4) Guaiacol contributes to the pleasing characteristic odor of some roasted foodstuffs, most notably of Arabica coffee 5) and barley malt. 6) Yet in other analyses, the production of guaiacol has been found to cause phenolic or smoky off-odors in fruit juice, 7) chocolate ice cream, 8) chocolate milk, 9) vanilla yogurt, 10) and vanilla ice cream. 11) Grassenmeier et al have classified the ethanol extracts of Madagascar beans into four aroma profile groups and calculated the average vanillin content of each group.…”

Testing and Demonstration of Small Scale Tomato Processing Technologies in Amhara Region Fogera District

“…This is in contrast with odour or visual defects, which can originate from some small areas of the tissue. In many cases, the micro-organisms responsible for the presence of offodours and off-flavours have not been fully identified [11].…”

Analysis of food taints and off-flavours: a review

“…The micro-organisms generally associated with off-favours in food, bacteria and fungi have been reviewed by Whitfield (1998). The food affected, includes meat, dairy products, fruit, vegetables and cereals, and a wide range of compounds with varied sensory descriptors can be produced (Whitfield, 2003;Springett, 1993).…”

“…However, this distinction is seldom made, particularly in consumer complaints, as both can be picked up by odour or taste and give the impression of poor food quality. Previous reviews on food taints have discussed the origins of food taints in detail (Mottram 1998;Whitfield 1998), but this review also considers the analytical approach to the determination of both known and unknown tainting compounds and includes methods introduced in recent years for taint analysis.…”