Traditional goatskin churn (Chekoua): quality of fermented goat milk flavoured with leaves of Phoenician juniper stored under ambient conditions

Abstract

Goat milk possesses several nutraceutical and functional properties. This study focused on the physicochemical and bacteriological properties of a local, traditionally fermented raw goat milk from Southern Algeria supplemented with the leaves of the Phoenician juniper. Analysis of the goat milk sample supplemented with juniper leaves was conducted against a control sample (without juniper leaves) and stored in a traditional goatskin churn (Chekoua) at ambient temperature. Some physicochemical parameters were tracked, namely pH, titratable acidity, temperature, lactose content, and total dry matter. The microbiological analysis included the following parameters: the total aerobic mesophilic flora, fungal flora, total and thermotolerant coliforms, coagulase-positive staphylococci, faecal streptococci, lactic acid bacteria, and the pathogenic bacteria Salmonella spp and Listeria monocytogenes. The obtained results showed an evolution of the physicochemical parameters during five days of conservation by increasing the titratable acidity, which proved to be significant for the test sample supplemented with J. phoenicea leaves compared to the control sample. The microbiological quality was characterized by the absence of pathogenic species, and a reduction of bacterial contaminants (probably due both to the effect of milk fermentation and the addition of juniper leaves as an aromatic plant endowed with antimicrobial properties). The study results showed that both goatskin and Phoenician juniper leaves can be used to improve the microbiological and sensory quality of fermented goat milk stored in the open air by the inhabitants of Southern Algeria. Such an artisanal practice should be maintained as a regional tradition. Further studies on fermented goat milk and its dairy by-products are recommended.