Simple methods to predict the minimum baking time of bread

Baking is a complex transformation process since many coupled physical phenomena take place within the product. For practical industrial purposes, it would be desirable to count on simple methods to predict accurately the process time. Unlike food preservation operations, two different process times can be defined: the critical or minimum time is determined by the complete dough/crumb transition and ensures the acceptability of the product; the quality time is given by a target value of a certain sensory attribute (e.g. surface colour), and it is associated with preference of consumers. Despite the existing physics-based models which aim to describe comprehensively the baking process, there is a gap between academic knowledge and the industrial practice and needs of design engineers. Therefore, in this work we explore three simple methods to predict the minimum baking time of bread, which are based on a previously developed and validated heat and mass transport model. All three simple methods (two heat transfer models and one regression equation) predict very well the critical time for a wide and common range of operating conditions; mean absolute relative error is 3.61%, 1.17% and 0.30%, respectively. The degree of difficulty regarding implementation of simple methods is also discussed. Finally, it is demonstrated that heat and mass transfer can be decoupled for certain calculations, by using appropriate simplifications based on knowledge of transport phenomena governing the process.Fil: Purlis, Emmanuel. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Universidad Nacional de la Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos; Argentin

Bread baking: Technological considerations based on process modelling and simulation

This paper presents a study of bread baking, mainly from a technological point of view, i.e. focused on transport phenomena and major quality changes occurring during the process. Such study was carried out by numerical simulation of a previously developed and validated mathematical model, which describes the simultaneous heat and mass transfer (with phase change in a moving boundary) taking place in bread during baking. Kinetic models for starch gelatinization and browning development were coupled to the transport model. Input variables to the model were oven temperature, heat transfer coefficient, and bread radius. A total of 105 operating conditions were simulated using the finite element method, and the end point of baking was established for three values of surface lightness. It is shown that an intense heating strategy can produce a browned but unbaked product, besides nutritional quality is negatively affected. Furthermore, minimization of baking time is restricted by internal resistance to heat transfer.Fil: Purlis, Emmanuel. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos; Argentin

Browning development in bakery products: A review

This paper presents a review regarding several aspects of the development of browning during baking of bakery products, mainly from an engineering point of view. During baking, the formation of colour is due to the Maillard reaction, and caramelization of sugars. Besides the major influence of this phenomenon on the initial acceptance of products by consumers, it is the responsible for other relevant changes occurring in food during baking, i.e. production of flavour and aroma compounds, formation of toxic products (e.g. acrylamide), and decrease of nutritional value of proteins. As well as baking, the development of browning in bakery products is a simultaneous heat and mass transfer process that occurs mostly in a non-ideal system under non-ideal conditions. In addition, the mechanisms of chemical reactions involved are still not elucidated completely, so the process is difficult to control and represents a major challenge for food engineers. Effects of browning on properties of products and experimental, modelling and technological aspects of colour formation during baking are reviewed.Fil: Purlis, Emmanuel. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos; Argentina. Universidad Nacional de La Plata. Facultad de Ingeniería; Argentin

Baking process design based on modelling and simulation: towards optimization of bread baking

This paper presents a theoretical approach for optimal design of the baking process. Conventional baking of bread was taken as subject of study, and simulation of previously validated models was used to investigate the process. The proposed approach is based on the definition of two different times for the baking process: a critical time, i.e. a minimum baking time assessed by the complete starch gelatinization in the product, and a quality time, i.e. the time necessary to achieve a target value for a given quality attribute. In this work, browning determined the quality time due to its relevance with regard to sensory and nutritional aspects. As a result, feasible solutions are obtained involving a minimum baking (acceptable products) and a minimum thermal input for a given value of browning, which helps to reduce the formation of acrylamide. Optimum solutions can be then obtained by defining specific objectives; weight loss can be minimized by lowering the value of heat transfer coefficient. Furthermore, obtained results can be helpful to build more efficient ovens.Centro de Investigación y Desarrollo en Criotecnología de Alimento

Bread baking as a moving boundary problem. Part 1: Mathematical modelling

A mathematical model for the bread baking process is developed in this work. Experimental data (temperature, water content, weight loss, crust thickness) obtained during baking is used to well understand the simultaneous heat and mass transfer occurring during the process. The evaporation-condensation mechanism is responsible for the rapid heating of the porous matrix and takes place either in a closed (dough) or open (crumb) structure. The existence of a moving evaporation front inside bread, which is a determining step of baking, is incorporated in a model applying a moving boundary formulation with equivalent thermophysical properties. The approach proposed here can be extended to other similar processes such as baking of other products (e.g. biscuit, cake), high-temperature drying, cooking and roasting.Fil: Purlis, Emmanuel. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos; ArgentinaFil: Salvadori, Viviana Olga. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos; Argentin

A moving boundary problem in a food material undergoing volume change - Simulation of bread baking

This paper presents a mathematical model for describing processes involving simultaneous heat and mass transfer with phase transition in foods undergoing volume change, i.e. shrinkage and/or expansion. We focused on processes where the phase transition occurs in a moving front, such as thawing, freezing, drying, frying and baking. The model is based on a moving boundary problem formulation with equivalent thermophysical properties. The transport problem is solved by using the finite element method and the Arbitrary Lagrangian-Eulerian method is used to describe the motion of the boundary. The formulation is assessed by simulating the bread baking process and comparing numerical results with experimental data. Simulated temperature and water content profiles are in good agreement with experimental data obtained from bread baking tests. The model well describes the stated general problem and it is expected to be useful for other food processes involving similar phenomena.Fil: Purlis, Emmanuel. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos; Argentina. Universidad Nacional de La Plata. Facultad de Ingeniería; ArgentinaFil: Salvadori, Viviana Olga. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos; Argentina. Universidad Nacional de La Plata. Facultad de Ingeniería; Argentin

Bread baking as a moving boundary problem. Part 2: Model validation and numerical simulation

A simultaneous heat and mass transfer model proposed to describe the bread baking process is validated. The mathematical model is based on a moving boundary problem formulation with equivalent thermophysical properties and includes the moving evaporation front, the evaporation-condensation mechanism and the development of the crust observed during bread baking. The problem is solved over an irregular three-dimensional geometry using the finite element method. Variation in temperature and water content of bread during baking is predicted with high accuracy by the model. Parameter estimation procedure and sensitivity analysis are performed for some thermophysical properties. The proposed formulation and analysis can be applied for other bakery products as well as for similar food engineering applications.Fil: Purlis, Emmanuel. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos; ArgentinaFil: Salvadori, Viviana Olga. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos; Argentin

Geometric modelling of heterogeneous and complex foods

A procedure to obtain realistic geometric models of foods having different inner tissues or sub–regions is developed. The proposed methodology consists in colour segmentation of food images using a distance criterion, obtaining a reduced set of pixels representing univocally all boundaries of food sub–regions, and finally construction of the geometric model through linear interpolation. The procedure was applied to samples of different nature and complexity. The geometric models were assessed in two different ways, i.e. evaluating the performance of the image segmentation step and simulating a chilling process. The former provided an objective assessment while the later verified the usefulness of the geometric models. An optimized scenario was found between the approximation degree of the food boundaries and the computational resources involved in process simulation. Furthermore, the presented procedure can be used to perform food quality evaluation.Fil: Goñi, Sandro Mauricio. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos; ArgentinaFil: Purlis, Emmanuel. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos; Argentin

Bread baking: technological considerations based on process modelling and simulation

This paper presents a study of bread baking, mainly from a technological point of view, i.e. focused on transport phenomena and major quality changes occurring during the process. Such study was carried out by numerical simulation of a previously developed and validated mathematical model, which describes the simultaneous heat and mass transfer (with phase change in a moving boundary) taking place in bread during baking. Kinetic models for starch gelatinization and browning development were coupled to the transport model. Input variables to the model were oven temperature, heat transfer coefficient, and bread radius. A total of 105 operating conditions were simulated using the finite element method, and the end point of baking was established for three values of surface lightness. It is shown that an intense heating strategy can produce a browned but unbaked product, besides nutritional quality is negatively affected. Furthermore, minimization of baking time is restricted by internal resistance to heat transfer.Centro de Investigación y Desarrollo en Criotecnología de Alimento

Modelling volume change and deformation in food products/processes: An overview

Volume change and large deformation occur in different solid and semi-solid foods during processing, e.g., shrinkage of fruits and vegetables during drying and of meat during cooking, swelling of grains during hydration, and expansion of dough during baking and of snacks during extrusion and puffing. In addition, food is broken down during oral processing. Such phenomena are the result of complex and dynamic relationships between composition and structure of foods, and driving forces established by processes and operating conditions. In particular, water plays a key role as plasticizer, strongly influencing the state of amorphous materials via the glass transition and, thus, their mechanical properties. Therefore, it is important to improve the understanding about these complex phenomena and to develop useful prediction tools. For this aim, different modelling approaches have been applied in the food engineering field. The objective of this article is to provide a general (non-systematic) review of recent (2005–2021) and relevant works regarding the modelling and simulation of volume change and large deformation in various food products/processes. Empirical-and physics-based models are considered, as well as different driving forces for deformation, in order to identify common bottlenecks and challenges in food engineering applications.Fil: Purlis, Emmanuel. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos; ArgentinaFil: Cevoli, Chiara. Università di Bologna; ItaliaFil: Fabbri, Angelo. Università di Bologna; Itali