Method of operating an appliance for processing food, in particular baking oven, wherein the appliance comprises a chamber adapted to accommodate and process at least a food item, wherein the method comprises the steps of a) capturing at least one image of the at least one food item placed or to be placed into the chamber; b) extracting a set of characteristic features of at least one of the at least one food item from the captured image; c) assigning at least one food category to at least one of the at least one food item based on the characteristic features and a user input, wherein assigning a food category to the food item comprises the step of comparing the extracted characteristic features to at least one dataset stored in a feature database, which at least one dataset comprises a set of characteristic features of at least one food item and an assigned food category, and wherein the step of comparing the extracted features to stored datasets in the database is conducted only if a preset number of datasets is stored in the database; d) generating and storing an additional new dataset, comprising the extracted set of features linked to the assigned food category, in the feature database at least if at least one of the following situations applies: i. the extracted set of characteristic features is not contained in the database; ii. the extracted set of characteristic features differs from a dataset stored in the database by a predefined amount; and iii. the assigned food category differs from a predefined or stored food category linked to the extracted set of characteristic features or a similar dataset; wherein additional new datasets and/or a training dataset built up by the user are continuously stored in the database and wherein in an initial phase of the method any of an extracted set of characteristic features together with a linked food category is stored as an additional new dataset in the database; and e) executing a food processing program assigned to the extracted set of characteristic features and food category, wherein the food processing program is at least one of automatically and manually assigned to the extracted set of characteristic features and food category, wherein an automatic assignment of the food processing program comprises the step of comparing the extracted set of characteristic features and food category with datasets stored in the database and selecting a processing program linked to a stored dataset identical or, within preset boundaries, similar to the extracted set of characteristic features and food category. a) capturing at least one image of the at least one food item placed or to be placed into the chamber; b) extracting a set of characteristic features of at least one of the at least one food item from the captured image; c) assigning at least one food category to at least one of the at least one food item based on the characteristic features and a user input, wherein assigning a food category to the food item comprises the step of comparing the extracted characteristic features to at least one dataset stored in a feature database, which at least one dataset comprises a set of characteristic features of at least one food item and an assigned food category, and wherein the step of comparing the extracted features to stored datasets in the database is conducted only if a preset number of datasets is stored in the database; d) generating and storing an additional new dataset, comprising the extracted set of features linked to the assigned food category, in the feature database at least if at least one of the following situations applies: i. the extracted set of characteristic features is not contained in the database; ii. the extracted set of characteristic features differs from a dataset stored in the database by a predefined amount; and iii. the assigned food category differs from a predefined or stored food category linked to the extracted set of characteristic features or a similar dataset; wherein additional new datasets and/or a training dataset built up by the user are continuously stored in the database and wherein in an initial phase of the method any of an extracted set of characteristic features together with a linked food category is stored as an additional new dataset in the database; and i. the extracted set of characteristic features is not contained in the database; ii. the extracted set of characteristic features differs from a dataset stored in the database by a predefined amount; and iii. the assigned food category differs from a predefined or stored food category linked to the extracted set of characteristic features or a similar dataset; e) executing a food processing program assigned to the extracted set of characteristic features and food category, wherein the food processing program is at least one of automatically and manually assigned to the extracted set of characteristic features and food category, wherein an automatic assignment of the food processing program comprises the step of comparing the extracted set of characteristic features and food category with datasets stored in the database and selecting a processing program linked to a stored dataset identical or, within preset boundaries, similar to the extracted set of characteristic features and food category.