MOULAYABDELLAH, HakimaMAATALLAH, Sara2023-04-032023-04-032019https://dspace.univ-ghardaia.edu.dz/xmlui/handle/123456789/5935The purpose of this work is to study the physico-chemical and bacteriological parameters of the margins of three olive varieties from two extraction systems: traditional and three-phase centrifugation. Physico-chemical analysis are carried out on the margins: (pH, turbidity, conductivity, temperature, humidity, organic matter, dry matter, mineral matter, calcium, magnesium, chlorurer, DBO5, total sugar). They showed that these effluents overloaded with organic matter evaluated in terms of DBO5 (66 g O2/l.). They are also characterized by an acidic pH (4.60-5) and very high conductivity (14.58 ms/cm). and richer by mineral elements: calcium (120.24mg/l). Magnesium (340.20mg/l). Chloride (142mg/l).the higher margin humidity (98.08%).The results obtained show that these margins are very humid, acidic and overloaded with organic matter.frMargin, extraction systems, olive variety, physico-chemical characterizationMargines, systèmes d’extraction, variété d’olive, caractérisation physico-chimique.