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Trans-resveratrol and trans-ε-viniferin were extracted from milled grape canes using pressurized lowpolarity water. The effects of temperature were significant for both compounds (p≤0.05): extraction at 160°C resulted in a 40% loss of trans-resveratrol compared to 95°C while reduction of trans-ε-viniferin at both temperatures remained at 30%. Increasing ethanol concentration from 0% to 25% increased the extraction of total phenolics and trans-ε-viniferin by 44% and 489%, respectively. Solvent flow rate also influenced trans-ε-viniferin extraction. Antioxidant activity showed a strong correlation with total phenolic content of the extracts, and the two target phenolic compounds. Except for the modifier concentration, the extraction parameters studied were not statistically significant with respect to the antioxidant activity of extracts (p> 0.05). Effective diffusivities of trans-resveratrol multiplied from 3.3×10 −11 to 10.4×10 −11 m 2 /s by three times with increasing temperature. The modified Gompertz equation satisfactorily explained the extraction of the stilbenes investigated. Nomenclature CSolute concentration at any location in the particle at time t, mg/mL C i Initial solute concentration, mg/mL D eff Effective diffusivity, m 2 /s D o Initial diffusivity, m 2 /s t Extraction time, s r Radial distance coordinate from centre of spherical particle, m R Average particle radius, m M t Total amount of solute removed from grape cane at time t, mg/g dw M ∞ Maximum amount of solute extracted at equilibrium, mg/g dw y Total amount of phenolic compound extracted from grape cane sample at time t, mg/g dw y ∞Maximum amount of phenolic compound extractable at equilibrium, mg/g dw m Maximum extraction rate defined as the tangent in the inflection point, mg/(g·min) eIrrational constant (exp(1)=2.718…) λTime period, min E a Activation energy for diffusion, kJ/mol R Universal gas constant, kJ/(mol·K) T Absolute temperature, K

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The purpose of this work was to derive multiparameter models for predicting density and viscosity of grape juice as a function of concentration and temperature. The experimental data of density and viscosity of grape juice at different concentrations and temperatures were utilized to derive the multiparameter models. the derived models satisfactorily represented the variation of density and viscosity of grape juice in the concentration and temperature ranges 19‐35 °Brix, 20‐80C, respectively.