Functional Dairy Products Including Pro/Pre/Symbiotics
Fabio Minervini1, Maria De Angelis1 and Marco Gobbetti2
- 1 Department of Soil, Plant and Food Sciences, University of Bari, Bari, Italy
- 2 Faculty of Science and Technology, Free University of Bozen, Italy
Definition and Classification of Functional Food
The term functional food was first proposed in Japan in the last decade of the twentieth century. In Japan, functional food has been legally acknowledged and labeled as Foods for Specified Health Use (FOSHU) (Stanton et al., 2005). Functional food may be defined in different ways, depending on the country. However, the generally accepted definition is "foods that, although similar in their aspect to conventional food, have a potentially positive effect on health beyond basic nutrition” (Tee, 2005; Kalra, 2003).
Apart from functional food available in nature, at least four categories of functional food should be considered: (i) fortified food; (ii) enriched foods; (iii) altered foods; and (iv) enhanced commodities (Spence, 2006). Fortified foods are items wherein the content of existing nutrients has been increased. An example of fortified dairy products is given by cheeses produced through the use of bacteria capable of converting linoleic and linolenic acids into the corresponding, biologically active, conjugated isomers (Gorissen et al., 2015). Enriched foods are items wherein a given nutrient or component is added to an item that normally does not contain that nutrient/component. Dairy foods containing probiotic bacteria represent one of the most frequent examples of enriched foods (Spence, 2006). Functional foods (altered foods) may be obtained by replacing existing components with beneficial components, such as in the case of dairy products containing inulin or vegetable fat as milk fat replacers (Conte et al., 2014; Salem et al., 2007). Enhanced commodities are raw food items whose nutrient composition has been altered in origin. Several examples of such kind of functional foods are vegetables with constitutively higher concentration of a given phytochemical (Mehta et al., 2002). However, such functional foods may be encountered in the dairy field—for instance, raw milk whose concentration in conjugated linoleic acids (CLA) has been increased upon modification of animal diet (Gorissen et al., 2015).
Basically, fortified/enriched foods may be obtained by exogenously adding in the food matrix a given component or nutrient, either in purified form or in form of a food whose origin differs from that of the food to be fortified/enriched. Dairy beverages enriched with cholesterol-lowering, vegetable-associated phytosterols are good
Advances in Dairy Products, First Edition.
Edited by Francesco Conto, Matteo A. Del Nobile, Michele Faccia, Angelo V. Zambrini, and Amalia Conte. © 2018 John Wiley & Sons Ltd. Published 2018 by John Wiley & Sons Ltd.
examples of such technology (Noakes et al., 2005). Another way for obtaining functional foods consists in the use of selected, food-grade microorganisms that may increase the concentration and/or the bioavailability of a given component/nutrient or may release (or synthetize themselves) one or more physiologically active compounds (Hansen, 2002). For instance, during milk fermentation, some lactic acid bacteria hydrolyze caseins, thus releasing antihypertensive peptides (Shah, 2007). During cheese ripening some others convert glutamate into y-aminobutyric acid (GABA), a compound with several biological activities (Nomura et al., 1998). Compared to other technologies, the use of selected microorganisms for obtaining functional food is advantageous, mainly because microorganisms are capable of growing at high rates on relatively poor substrates. While growing, microorganisms release biologically active compounds, acting as real cell factories (Gobbetti et al., 2010).
A huge number of nutrients/components may be exploited for obtaining functional dairy foods. The focus of this chapter is on probiotic microorganisms and related food components (prebiotic compounds and synbiotic food), bioactive peptides, GABA, phytochemicals, and dairy products with altered lipid composition (Figure 18.104.22.168).