Alistair J. Carr

General Aspects of Cheese Technology

Abstract This chapter describes the steps involved in the cheese making process, explaining their purpose and then describes the equipment and manufacturing processes that have been developed to facilitate large scale cheese manufacture. The initial focus is on the common processing steps to the end of the vat stage of manufacture, including descriptions of common cheese vat configurations. This is followed by discussion of the technology used for postvat processing for different cheese groups including dry salt varieties (cheddaring, stirring, milling, salting, block forming and packaging) and brine salt varieties (prepressing, block filling, pressing and brining). Continuous or semicontinuous production methods are described as an alternative to the traditional batch process. A section is also dedicated to processing equipment for pasta filata cheeses, such as cooker-stretchers and extruders. The chapter then moves to a discussion of recent processing developments designed to optimize cheese offerings with an end customer or consumer in mind, such as individually quick-frozen cheese shreds for pizza use and multistage drying of cheese ingredients for processed cheese manufacture. This is followed by a review of more recent technological advances in cheese manufacturing wherein the entire cheese processing is reenvisioned. Such processes include the uncoupling of curd formation from renneting and the removal of separate curd formation and dewheying operations in processes that are made possible by borrowing technologies traditionally used only in the manufacture of noncheese dairy products.

Functional Milk Proteins Production and Utilization: Casein-Based Ingredients

Casein based ingredients have a long history of use, in both food and non-food applications, due to the ease with which their functional properties can be manipulated. However with the advent of functional and cheaper non-casein alternatives, manufacturers have had to be innovative in both their manufacturing processes and in seeking out new applications. This necessity, through the development of membrane and ion-exchange based ingredients, has led to the demise in the importance of traditional casein products. This chapter reviews the processing and application developments for both traditional and newer ingredients with a focus on how to reduce cost to both the ingredient and application manufacturers while meeting the market demands of ingredient flexibility and quality to enable holistic product design.

The Development of Expanded Snack Product Made from Pumpkin Flour-Corn Grits: Effect of Extrusion Conditions and Formulations on Physical Characteristics and Microstructure

Pumpkin products confer natural sweetness, desirable flavours and β-carotene, a vitamin A precursor when added as ingredients to extruded snacks. Therefore, a potential use for dried pumpkin flour is as an ingredient in ready-to-eat (RTE) snack foods. Growth in this market has driven food manufacturers to produce a variety of new high value snack foods incorporating diverse ingredients to enhance the appearance and nutritional properties of these foods. Ready-to-eat snacks were made by extruding corn grits with 5%, 10%, 15% and 20% of pumpkin flour. Snacks made from 100% corn grits were used as control products for this work. The effect of formulation and screw speeds of 250 rpm and 350 rpm on torque and specific mechanical energy (SME, kWh/kg), physical characteristics (expansion ratio, bulk density, true density and hardness) and the microstructure of the snacks were studied. Increasing the screw speed resulted in a decrease of torque for all formulations. When pumpkin flour was added the specific mechanical energy (SME) decreased by approximately 45%. Increasing the percentage of pumpkin flour at the higher screw speed resulted in a harder texture for the extruded products. X-ray tomography of pumpkin flour-corn grit snacks showed that increased levels of pumpkin flour decreased both the bubble area and bubble size. However, no significant differences (p > 0.05) in bubble wall thickness were measured. By understanding the conditions during extrusion, desirable nutritional characteristics can be incorporated while maximizing expansion to make a product with low bulk density, a fine bubble structure and acceptable organoleptic properties.

Assessing the iron chelation capacity of goat casein digest isolates

We isolated goat phosphopeptides via calcium and ethanol precipitation from a caseinate digest and investigated their feasibility as an iron-fortification ingredient in nutritional foods. Goat tryptic-digested phosphopeptides could bind 54.37 ± 0.50 mg of Fe/g of protein compared with goat milk, which could bind 3.83 ± 0.01 mg of Fe/g of protein, indicating that isolation did increase iron binding. However, the >13-fold increase in iron binding was only partly explained by the increased concentration of phosphoserine-rich residues in the isolated fraction: we observed a 77% increase in serine residue content and a 5.9-fold increase in phosphorus in the goat peptide isolate compared with the starting caseinate material. We investigated the effect of potential industrial processing conditions (including heating, cooling, holding time, and processing order) on iron binding by the tryptic-digested phosphopeptides. In addition, we tested the effect of ionic strength and the addition of peptides to a milk system to understand how food formulations could affect iron binding.

Mozzarella Cheese – A Review of the Structural Development During Processing

From its journey from milk through to its end use, Mozzarella cheese undergoes significant transformations in its makeup of components and their structural arrangement. The typical Mozzarella processing steps each alter the structural configuration of the system. The colloidal dispersion of proteins, fat, lactose and minerals that is milk experiences physical, thermal, chemical, biological and ionic induced changes to its composition and structure throughout the manufacturing process and storage. This review critically evaluates the literature related to the structural changes occurring as a result of each step in Mozzarella cheese production process. Emphasis is placed on the role of each step and the induced transformations at the micro and macro scale in the system. Additionally, the review also looks at the changes that occur as a result of storage. This evolution in structure culminates in the creation of an end product with a bi-continuous gel structure that has a desired functionality in its end use.

Chapter 26 – General Aspects of Cheese Technology

This chapter describes the steps involved in the cheese making process, explaining their purpose and then describes the equipment and manufacturing processes that have been developed to facilitate large scale cheese manufacture. The initial focus is on the common processing steps to the end of the vat stage of manufacture, including descriptions of common cheese vat configurations. This is followed by discussion of the technology used for postvat processing for different cheese groups including dry salt varieties (cheddaring, stirring, milling, salting, block forming and packaging) and brine salt varieties (prepressing, block filling, pressing and brining). Continuous or semicontinuous production methods are described as an alternative to the traditional batch process. A section is also dedicated to processing equipment for pasta filata cheeses, such as cooker-stretchers and extruders. The chapter then moves to a discussion of recent processing developments designed to optimize cheese offerings with an end customer or consumer in mind, such as individually quick-frozen cheese shreds for pizza use and multistage drying of cheese ingredients for processed cheese manufacture. This is followed by a review of more recent technological advances in cheese manufacturing wherein the entire cheese processing is reenvisioned. Such processes include the uncoupling of curd formation from renneting and the removal of separate curd formation and dewheying operations in processes that are made possible by borrowing technologies traditionally used only in the manufacture of noncheese dairy products.