Effect of food structure on microbial growth and on the activity of stress factors

CAMPOS, CARMEN A.; GLIEMMO, MARÍA F.; ZALAZAR, ALDANA L.; CASTRO, MARCELA P.; SCHELEGUEDA, LAURA I.

Food Microbiology: Fundamentals, Challenges and Health Implications

Nova Publishers

Lugar: Nueva York; Año: 2015; p. 1 - 24

The ability of microorganisms to grow on foods depends on storage conditions, food composition, presence of additives and food structure. The latter modify the way of microorganism growth, in the case of liquids, it occurs planktonically. But, in structured foods the mobility is restricted; microorganisms are immobilized and grow as colonies. It must be considered that most of food products present some degree of structure, such as the case of emulsions, gels and solid foods. However the effect of structure on microbial growth is scarce evaluated specially when dealing with spoilage flora. Trends observed about the effect structure on microbial growth are diverse. On one hand many studies postulate that structure acts as an additional stress factor and therefore lower growth is expected in these kinds of products. On the other hand other studies show that structure increases growth probability. The main objective of this chapter is to review the bibliography concerning the effect of structure on microbial growth and on the activity of stress factors with special emphasis on water activity (aw) depressors and on antimicrobial agents. This information will help to choose the conditions that assure food microbial stability and contribute to improve the food safety and quality.