Use of phenolic compounds from cocoa pod-husks (Theobroma cacao L.) as inhibitors of Salmonella spp. in fresh cheese produced in Manabí, Ecuador

Abstract

Cocoa pod-husk is a by-product of cocoa processing, underutilized despite its phenolic compounds that can be an alternative to preserve the microbiological quality of food. The aim of this work was to evaluate the in vitro inhibitory activity of phenolic compounds from the cocoa pod-husk against Salmonella spp, which is commonly found in fresh cheese produced in Manabí, Ecuador; as well as the effect on the sensory characteristics of cheese after immersion in a solution of phenolic compounds. In vitro microbiological analyzes of the inhibitory activity of phenolic compounds, showed that the concentrations 1 and 1.5% had the highest zone of inhibition against Salmonella spp., with mean diameters of 10.67 and 11.8 mm, respectively. On the other hand, the growth curve of Salmonella spp. indicated that 2 h were required for complete inhibition of bacteria by phenolic compounds at concentrations of 1 and 1.5%. For the sensory analyzes of cheese treated with phenolic compounds, 56.3% of the panelists accredited the firmness and odor with “I like it”, while 37.5% of the panelists qualified the color of the cheese with “I neither like nor dislike”. Firmness and odor had higher values of acceptance than color. For 25 and 12.5% of the panelists, firmness and odor were rated as “I like it a lot”, respectively, and 56.3% of the panelists conferred the label of “I like it” to both attributes. Cheese color was the lowest rated attribute, given that 12.5% of the panelists chose “I like it a lot” and 25% for “I like it”.