a b s t r a c tThe thermally assisted mechanical dewatering (TAMD) process is a new intensive solid/liquid separation device. When applied to 'nature-wet' biomass, the TAMD process significantly enhances the separation yield. The TAMD process couples in one stage a mechanical dewatering at low pressure (P applied = 300 kPa in the present study) with a moderated heating (T wall ≤ 90 • C). An increment of pressure can be applied in a second stage to further enhance the dry solid content of the press cake. In the present study, the TAMD process was used to dewater spinach leaves and alfalfa stems and leaves. The influence of cutting, pulping and temperature on the fractionation kinetics and the extraction yield were specifically investigated. Experiments were carried out on a laboratory compression cell, heated through the piston. Results show that, at ambient temperature, pulping is an essential pre-processing unit operation to reach an extraction yield of 55%. Under moderate heating conditions (T wall = 50 or 70 • C), a thermally assisted mechanical dewatering, without any pre-processing stage, can remove 69% of the inherent water from alfalfa, that is to say an increase by 23% of the yield. But, compared with the conventional fractionation process, the duration of the mechanical fractionation must be at least twice longer. Beyond 70 • C, the temperature does not have any influence on the extraction kinetics. Cutting has a very limited influence with an enhancement of the dry solid content from 2 to 5% at best.

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a b s t r a c tThe thermally assisted mechanical dewatering (TAMD) process proved to be efficient to dewater various biomasses. The main idea of this process is to supply heat by conduction through the press walls during the wet fractionation. Applied to spinach leaves, this process led to energy saving but also to a larger amount of green juice. In order to optimize the TAMD process and to evaluate the valorisation potential of the liquid fraction produced, the physico-chemical characteristics of the green juice were investigated.In addition to conventional characterisation methods, an analysis method specific to Rubisco protein (ribulose-1,5-bisphosphate carboxylase/oxygenase) has been developed in the present work. The method enables detection and quantification of Rubisco in green juice samples by using size exclusion chromatographic principles (HPLC SEC).Global methods showed that cut degree of the biomass leaves has an effect on the liquid fraction produced. Indeed, nitrogen content, green and white proteins contents are higher when leaves are finely cut.The investigation of temperature processing effect on juice characteristics by applying the different characterisation methods leads to: -At high temperature (90 • C), low nitrogen and fractionated proteins contents in juice, which means that an enriched press cake is produced. -At medium temperature (50 • C), higher nitrogen content in juice, which means that a polypeptides-rich liquid I produced. -At low temperature (30 • C), HPLC SEC method developed revealed that TAMD process produced a green juice containing biomolecules of high added value such as Rubisco protein.