A process for imparting specific work to a fat based edible material to reduce the viscosity of the material until the material reaches a pre-determined target viscosity (η target), the process comprising the steps of: (a) imparting a total amount of specific work ω into the fat based edible material using an energy delivery means operated by one or more control parameter(s), where both the rate at which and total amount of specific work is imparted to the material is determined by the one or more control parameter(s); and where the fat based material flows through the energy delivery means at an instant flow rate at a given moment in time 't' after the start of step (a) which flow is denoted by Q t (b) controlling the energy delivery means to reach a pre-determined target viscosity (η target); where the rate of specific work imparted to the fat based material is determined by controlling one or more of the control parameter(s), such that the specific work imparted by the energy delivery means at a time t' after the start of step (a) satisfies the relationship given in equation 1: ln η t = A − B ln π t where (i) eta ( η t) denotes the viscosity at the time t' after the start of step (a) of the fat based material measured as plastic viscosity according to ICA method 46; (ii) omega ( ω t) denotes total amount of specific work delivered to the fat based material after time t' since the start of step (a) calculated from the power and flow rate as given equation: π t = P t Q t where: P t denotes the power (measured in kilowatts (kW)) imparted to the fat based material by the energy imparting means at the time t' after the start of step (a) Q t denotes the instant flow rate (measured in kg per hour (kg/h)) of the fat based material through the energy delivery means at the time t' after the start of step (a); and (iii) A is from 0.5 to 0.7; and (iv) B is from 0.3 to 0.6. (c) stopping the energy delivery means after t = T from imparting specific work to the fat based material, the time T being determined from equations and and the pre-determined target viscosity (η target), wherein the fat based material is a choco-material (preferably chocolate or compound) and the process is used to liquefy the choco-material (i.e. pre-determined target viscosity (η target) is liquid). (a) imparting a total amount of specific work ω into the fat based edible material using an energy delivery means operated by one or more control parameter(s), where both the rate at which and total amount of specific work is imparted to the material is determined by the one or more control parameter(s); and where the fat based material flows through the energy delivery means at an instant flow rate at a given moment in time 't' after the start of step (a) which flow is denoted by Q t (b) controlling the energy delivery means to reach a pre-determined target viscosity (η target); where the rate of specific work imparted to the fat based material is determined by controlling one or more of the control parameter(s), such that the specific work imparted by the energy delivery means at a time t' after the start of step (a) satisfies the relationship given in equation 1: ln η t = A − B ln π t where (i) eta ( η t) denotes the viscosity at the time t' after the start of step (a) of the fat based material measured as plastic viscosity according to ICA method 46; (ii) omega ( ω t) denotes total amount of specific work delivered to the fat based material after time t' since the start of step (a) calculated from the power and flow rate as given equation: π t = P t Q t where: P t denotes the power (measured in kilowatts (kW)) imparted to the fat based material by the energy imparting means at the time t' after the start of step (a) Q t denotes the instant flow rate (measured in kg per hour (kg/h)) of the fat based material through the energy delivery means at the time t' after the start of step (a); and (iii) A is from 0.5 to 0.7; and (iv) B is from 0.3 to 0.6. (i) eta ( η t) denotes the viscosity at the time t' after the start of step (a) of the fat based material measured as plastic viscosity according to ICA method 46; (ii) omega ( ω t) denotes total amount of specific work delivered to the fat based material after time t' since the start of step (a) calculated from the power and flow rate as given equation: π t = P t Q t where: P t denotes the power (measured in kilowatts (kW)) imparted to the fat based material by the energy imparting means at the time t' after the start of step (a) Q t denotes the instant flow rate (measured in kg per hour (kg/h)) of the fat based material through the energy delivery means at the time t' after the start of step (a); and (iii) A is from 0.5 to 0.7; and (iv) B is from 0.3 to 0.6. (c) stopping the energy delivery means after t = T from imparting specific work to the fat based material, the time T being determined from equations and and the pre-determined target viscosity (η target), wherein the fat based material is a choco-material (preferably chocolate or compound) and the process is used to liquefy the choco-material (i.e. pre-determined target viscosity (η target) is liquid).