Structured food products

Initial work on the design of structured products has been presented by, for example, Meeuse et al. 2000, Wibowo and Ng, 2001, 2002. In this chapter a real life example of a process redesign project where process synthesis techniques were applied to a structured food product, is presented. First, we position this work in the framework of integrated product and process design. Then we describe how we translated existing process synthesis techniques into a useful methodology for structured products. Then the actual case study is presented. Finally some perspectives are given. 

The example presented in section 6.4 of this chapter showed that process synthesis can be applied to structured food products. Moreover this application is of true value since significant cost savings could be achieved. However, a complete methodology is not yet available. One of the main outstanding questions is how to perform the identified (necessary) tasks in an optimal sequence to obtain the desired product Besides this the success of application depends critically on the availability of domain knowledge about all relevant aspects of the process. Several factors relevant for food processing were not considered in this example ... 

The second challenge is to relate the desired product attributes to the material properties of the ingredients and the structure of the product. For example, the development process would have been much more efficient if a model was available to describe the behavior of cleansing bars and structured food products. Without the benefits of predictive models, as is the present status for many consumer products, extensive trial-and-error by experiments are required. Even if a comprehensive model based on first principles is not available, a combination of physical insights and heuristics can still help improve the development process. Chapters 1-2 report some new developments in this area. See also [11] for a more detailed discussion on the issues and needs related to the roles and uses of property models in product design. 

Natural herbicides produced by microorganisms have had a profound influence on world agriculture. Many species of higher plants have survived the ages because of their ability to detoxify or avoid the toxic effects of these compounds, and extensive effort has gone into the commercial breeding of other species to develop these abilities. Still, the structural variety of natural herbicides appears to be so great that their effects are still of major concern in food production. 

Aguilera, J. M. (2006). Food product engineering building the right structures. Journal of Science of Food and Agriculture, 86, 1147-1155. 

Dietary fibre, which comprises all the non-digestible structural carbohydrates of plant cell walls and any associate lignin, provides a further example of a complex food-borne factor which cannot be classified as a nutrient, and which continues to generate debate over such issues as definition and analytical techniques. However, whatever the unresolved complexities, dietary fibre has a lengthy history and had proved itself eminently suitable as a component of functional food products long before the term was even coined. 

Nevertheless, a mutual understanding about colors does work because conunon rules have been implemented by education, habituation, socially approved behavior, and properties that appear to individuals simultaneously, e.g., the vertical signal order of traffic lights. However, those rules are of limited value when color perception is the base for aesthetic appreciation as is the case for many industrial products and food products. In order to meet the demands of as many consumers as possible, producers look for a standard consumer who is most representative of the group. This requires establishment of a reliable measurement procedure that can be reproduced easily and be adapted to the various conditions under which it is applied light conditions, more or less opaque or translucent objects, object surface structures, etc. These measurement procedures were created more than a century ago and have... 

In the past 20 years, consumers have increasingly considered synthetic colorants undesirable or harmful but they are still used extensively in many food products. Official organizations in the United States and European Union have restricted the use of some synthetic colorants as additives in foods (see Table 7.3.1 in Section 7.3). The list of allowed colorants has been reduced to 21. Section 7.3 also discusses details about their structures. 

A typical characteristic of many food products is that these are multi-phase products. The arrangement of the different phases leads to a microstructure that determines the properties of the product. Mayonnaise, for example, is an emulsion of about 80% oil in water, stabilized by egg yolk protein. The size of the oil droplets determines the rheology of the mayonnaise, and hence, the mouthfeel and the consumer liking. Ice cream is a product that consists of four phases. Figure 1 shows this structure schematically. Air bubbles are dispersed in a water matrix containing sugar molecules and ice crystals. The air bubbles are stabilized by partial coalesced fat droplets. The mouthfeel of ice cream is determined by a combination of the air bubble size, the fat droplet size and the ice crystal size. 

Sulphonated azo dyes were separated and quantitated in various food products by ion-pair liquid chromatography with DAD and electrospray MS detection. The chemical structure of sulphonated azo dyes included in the investigation are shown in Fig. 3.36. Dyes were separated in an ODS column (125 X 2.0 mm i.d. particle size 5 pm) using gradient elution. An aqueous solution of 3 mM triethylamine (pH adjusted to 6.2 with acetic acid) and methanol... 

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