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Á. Farkas et al.
17.1 Introduction
In the last decades, the increased population and lifestyle changes promoted considerable alterations in the formulation of food products. Additionally, the modification
of the eating habits and the nutritional demands caused an important transformation
in the food industries, which involved the incorporation of additional food ingredients
to food products. The purpose of these compounds (food additives) is to add dietary
nutrition (fortifiers), increase the shelf life and/or to improve the physicochemical,
sensorial and microbiological properties of the industrialized foods (Damodaran and
Parkin 2017; Martins et al. 2019).
A recent review study states that, currently, there are almost 2500 types of food
additives used globally, and US FDA lists around 3000 ingredients in the food additive
database (Abdel 2015). It also reports that almost 200,000 tons of food additives are
used per year, which highlights the fact that Western diet consists of approximately
75% of processed food. The average annual intake of food additives per person is
estimated to be 3.6–4.5 kg (Abdel 2015).
Food additives are generally divided into six categories: taste enhancers, preservatives, stabilizers, emulsifiers, antioxidants and colouring agents. This chapter is
dedicated to the latter two categories.
Antioxidants are mainly used in food to prevent off-flavours by oxidation of
fats, therefore, halting their peroxidation in the initiation or propagation phases.
There are five types of antioxidants: the primary antioxidants known as radical scavengers or chain-breaking antioxidants; chelators, that bind to metals and prevent
them from initiating radical formation; quenchers, which deactivate high-energy
oxidant species; oxygen scavengers, that remove oxygen from systems, avoiding
their destabilization; and finally, the antioxidant regenerators, that regenerate other
antioxidants when these become radicalized. The main foods where antioxidants are
used are meats, oils, fried foods, dressings, dairy products, baked goods and extruded
snacks (Baines and Seal 2012; Carocho et al. 2015).
Food items that are rich in nutrients, flavour, aroma and texture are consumed
only if the colour exhibited makes its appearance relishing. Consumers are fond of
colourful food products and food dishes worldwide. Colour and appearance create
the first impression and greatly influence the acceptability of food; hence, the development of food items with attractive colour and appearance is an important goal in the
food industries. Colour is added to food to replace the colour lost during processing,
to enhance the colour already present, to minimize batch to batch variations and to
colour otherwise uncoloured food.
Food colours can be classified as natural colours, nature-identical colours,
synthetic colours and inorganic colours. Nowadays, food producers pay more attention to colours and additives of natural origin, since many artificial colours and additives have been shown to impart negative health effects. Based on the chemical structure, natural pigments are grouped as tetrapyrroles (e.g. chlorophyll), tetraterpenoids
(e.g. carotenoids), flavonoids (e.g. anthocyanins), anthraquinones (e.g. carmine, lac,
etc.) and betains (Arimboor et al. 2015).
Á. Farkas et al.
17.1 Introduction
In the last decades, the increased population and lifestyle changes promoted considerable alterations in the formulation of food products. Additionally, the modification
of the eating habits and the nutritional demands caused an important transformation
in the food industries, which involved the incorporation of additional food ingredients
to food products. The purpose of these compounds (food additives) is to add dietary
nutrition (fortifiers), increase the shelf life and/or to improve the physicochemical,
sensorial and microbiological properties of the industrialized foods (Damodaran and
Parkin 2017; Martins et al. 2019).
A recent review study states that, currently, there are almost 2500 types of food
additives used globally, and US FDA lists around 3000 ingredients in the food additive
database (Abdel 2015). It also reports that almost 200,000 tons of food additives are
used per year, which highlights the fact that Western diet consists of approximately
75% of processed food. The average annual intake of food additives per person is
estimated to be 3.6–4.5 kg (Abdel 2015).
Food additives are generally divided into six categories: taste enhancers, preservatives, stabilizers, emulsifiers, antioxidants and colouring agents. This chapter is
dedicated to the latter two categories.
Antioxidants are mainly used in food to prevent off-flavours by oxidation of
fats, therefore, halting their peroxidation in the initiation or propagation phases.
There are five types of antioxidants: the primary antioxidants known as radical scavengers or chain-breaking antioxidants; chelators, that bind to metals and prevent
them from initiating radical formation; quenchers, which deactivate high-energy
oxidant species; oxygen scavengers, that remove oxygen from systems, avoiding
their destabilization; and finally, the antioxidant regenerators, that regenerate other
antioxidants when these become radicalized. The main foods where antioxidants are
used are meats, oils, fried foods, dressings, dairy products, baked goods and extruded
snacks (Baines and Seal 2012; Carocho et al. 2015).
Food items that are rich in nutrients, flavour, aroma and texture are consumed
only if the colour exhibited makes its appearance relishing. Consumers are fond of
colourful food products and food dishes worldwide. Colour and appearance create
the first impression and greatly influence the acceptability of food; hence, the development of food items with attractive colour and appearance is an important goal in the
food industries. Colour is added to food to replace the colour lost during processing,
to enhance the colour already present, to minimize batch to batch variations and to
colour otherwise uncoloured food.
Food colours can be classified as natural colours, nature-identical colours,
synthetic colours and inorganic colours. Nowadays, food producers pay more attention to colours and additives of natural origin, since many artificial colours and additives have been shown to impart negative health effects. Based on the chemical structure, natural pigments are grouped as tetrapyrroles (e.g. chlorophyll), tetraterpenoids
(e.g. carotenoids), flavonoids (e.g. anthocyanins), anthraquinones (e.g. carmine, lac,
etc.) and betains (Arimboor et al. 2015).