Supervision of ovoproducts spoilage with red led light

Abstract

Heat-treatment of ovoproducts is often required to ensure microbial safety. However, it has been shown that in most microbial species slow heating, or heat shocks may induce a higher heat resistance, that means that it is not possible to remove the microbial flora completely. These microorganisms produce on ovoproducts spoilage especially when the cold chain is broken along the transportation and/or storage. As a result, the life span for the product is shortened. The microbial activity inside the product causes changes in several physical properties, which can be supervised using optical methods. The aim of this work is to monitor the sigmoid behaviour underlying the ovoproduct evolution and spoilage by means of red LED light. For two commercial types of liquid and pasteurized egg white, storage at 9ºC, an average correlation of r=0.94 has been found between microorganism growth and images mean grey level of LED light passing though the sample. The results show that it is possible to develop very simple predictive models taking into account only one optical parameter corresponding to a single LED