Mixing in the Food Industry
CHAPTER ONE
1.0 Introduction
At the heart of transforming raw ingredients into food for human consumption is the mixing operation. It’s a main task which other food processing steps also share to establish consistency. Whether a food product requires small-scale mixing by hand or high volume blending of multiple ingredients, home cooks and food process engineers alike know the importance of proper mixing. Even with the right amount of ingredients and flavors, a great recipe will not transform into good food unless the components are well-mixed. Taste, texture, color, appearance – these are all crucial parameters intimately influenced by the mixing process. Consumers expect that the food products they patronize will be exactly the same as the one they had last. It is easy to understand that within the food industry a high level of consistency is required not just batch-to-batch but facility-to-facility. In this market, consistency is the backbone of consumer loyalty.
1.1 Mixing
Mixing is the dispersing of components, one throughout the other. It occurs in innumerable instances in the food industry and is probably the most commonly encountered of all process operations. It can also be defined as the intermingling of two or more dissimilar portions of a material resulting in the attainment of a desired level of uniformity either physical or chemical in the final product (Lindley, 1991). Mixing is achieved by imparting forces to the mixture which creates motion. Very often, mixing occurs simultaneously with size reduction, as is the case in forming, homogenizing and emulsification. Mixing increases the homogeneity of a system by reducing non-uniformity or gradients in composition, properties or temperature. Besides the primary objective of homogeneity, secondary objectives of mixing include control of heat and mass transfer rates, reactions and structural changes (Harnby et al. 2001).
Mixing ensures delivery of a product with constant properties. Mixing may
1.0 Introduction
At the heart of transforming raw ingredients into food for human consumption is the mixing operation. It’s a main task which other food processing steps also share to establish consistency. Whether a food product requires small-scale mixing by hand or high volume blending of multiple ingredients, home cooks and food process engineers alike know the importance of proper mixing. Even with the right amount of ingredients and flavors, a great recipe will not transform into good food unless the components are well-mixed. Taste, texture, color, appearance – these are all crucial parameters intimately influenced by the mixing process. Consumers expect that the food products they patronize will be exactly the same as the one they had last. It is easy to understand that within the food industry a high level of consistency is required not just batch-to-batch but facility-to-facility. In this market, consistency is the backbone of consumer loyalty.
1.1 Mixing
Mixing is the dispersing of components, one throughout the other. It occurs in innumerable instances in the food industry and is probably the most commonly encountered of all process operations. It can also be defined as the intermingling of two or more dissimilar portions of a material resulting in the attainment of a desired level of uniformity either physical or chemical in the final product (Lindley, 1991). Mixing is achieved by imparting forces to the mixture which creates motion. Very often, mixing occurs simultaneously with size reduction, as is the case in forming, homogenizing and emulsification. Mixing increases the homogeneity of a system by reducing non-uniformity or gradients in composition, properties or temperature. Besides the primary objective of homogeneity, secondary objectives of mixing include control of heat and mass transfer rates, reactions and structural changes (Harnby et al. 2001).
Mixing ensures delivery of a product with constant properties. Mixing may
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