Apply hurdle technology to curry paste.
Many promising hurdles have been identified, although application of the concept has been largely restricted to the meat sector. Recent studies, however, emphasize a much wider potential application, such as in bakery products, fish and dairy products. More specifically, the technique was introduced into mild processing of fruits and vegetables. The design of new hurdles, such as gas packaging systems, bioconservation, bacteriocins, ultra-high pressure treatment and edible coatings, aided this development.
Consumers demand fresher and more natural products. This prompts food manufacturers to use milder preservation techniques and could be stimulating the current trend to hurdle technology. There is an urgent need for new or improved methods producing stable and safe foods. Hurdle technology deliberately combines existing and new preservation techniques to establish a series of preservative factors (hurdles) that the microorganisms in question are unable to overcome. These hurdles may be temperature, water activity, acidity, redox potential or preservatives, among others. A crucial phenomenon in hurdle technology is known as the homeostasis of microorganisms.
Homeostasis is the constant tendency of microorganisms to maintain a stable and balanced internal environment. Hurdles can disturb one or more of the homeostasis mechanisms, thereby preventing microorganisms from multiplying and causing them to remain inactive or even die. Researchers preserve food by disturbing the homeostasis of microorganisms. The best way to do this is to deliberately disturb several homeostasis mechanisms simultaneously. This multi-targeted approach is the essence of hurdle technology. It is more effective than single-targeting and allows the use of hurdles of lower intensity, improving product quality. There is the further possibility that different hurdles in a food not only have an added effect on stability, but can act synergistically.
Scientists at Thammasat University (Faculty of Sciences and Technology, Klong Luang District, Pathumthani 12121, Thailand) are applying hurdle technology to extend the shelf life of Thai red curry paste and Pad-Thai concentrate. They investigated the impact of using hurdles on the shelf life stability of Thai food and flavor ingredients. Two Thai red curry paste formulae of different initial Aw and pH were used, as well as one formula of low-viscosity prepared Pad-Thai concentrate. Researchers concluded that significant hurdles for improving the shelf life of Thai red curry paste include moisture, initial Aw, oxygen and storage temperature. Those for Pad-Thai concentrate include viscosity, pH and Aw.
Further information. S. Vadhanasin; email: firstname.lastname@example.org.