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Bread is one of the most common cereal foods, and intake is nearly ubiquitous among all people. Bread as a product is highly diverse, both in terms of ingredients (e.g., wheat, rye, corn/maize, barley, gluten‐free dough mixes) and processing (yeast leavened, sourdough, crispbread and unleavened flatbreads; short or long fermentation; use of enzymes and additives to improve shelf‐life and loaf properties). The whole grain content of bread varies between 0% and 100% of the flour component, with the increasing amount of whole grain in bread usually leading to denser loaf volume. However, the addition of baking improvers such as vital gluten or enzymes can give acceptable volume to breads with 100% or close to 100% whole grain. Some baking enzymes are known to have side activities that break down dietary fibre, which may be a concern as dietary fibre is sometimes used as a reference for whole grains in a product.

Table 5.1 Flour content and potential contribution to whole grain intake of common grain‐based products, based on Marquart et al 2006. Alkylresorcinol content is included to give an idea of how one proposed marker for whole grain reflects the proportion of whole grains in a product. Note that as alkylresorcinols are only present in wheat, rye, barley and quinoa, they do not universally reflect the whole grain content of foods.

Sources: Ross AB, Svelander C, Karlsson G et al. (2017) Identification and quantification of even and odd chained 5‐n alkylresorcinols, branched chain‐alkylresorcinols and methylalkylresorcinols in Quinoa (Chenopodium quinoa). Food Chem 220, 344–351; Chen Y, Ross AB, Åman P et al. (2004) Alkylresorcinols as markers of whole grain wheat and rye in cereal products. JAgricFood Chem 52, 8242–8246; Ross AB (2012) Analysis of alkylresorcinols in cereal grains and products using ultrahigh‐pressure liquid chromatography with fluorescence, ultraviolet, and coulArray electrochemical detection. J Agric Food Chem 60, 8954–8962; Ross AB, Kochhar S (2009) Rapid and sensitive analysis of alkylresorcinols from cereal grains and products using HPLC‐Coularray‐based electrochemical detection. J Agric Food Chem 57, 5187–5193; Andersson AAM, Åman P, Wandel M et al. (2010) Alkylresorcinols in wheat and rye flour and bread. J Food Compost Anal 23, 794–80.

Product	Flour/grain %	Type of grains	Serving size (fresh weight)	Maximum contribution to whole grain intake per serving (g)	Total alkylresorcinol content (μg/g dry weight)
Bread
White‐wheat bread	51	Wheat	28	0	20a
Whole‐wheat bread	51	Wheat	28	14	438a
Rye bread	42	Rye and wheat	30	12	412a
Breakfast cereal
Corn flakes		Corn	30	0	0
Whole wheat/rice flakes	80	Wheat and rice	30	24	251
Whole‐wheat biscuits	100	Wheat	40	40	478a
Bran‐based cereal	85	Wheat bran	40	0	1700
Rolled oats/oatmeal (not cooked)	100	Oats	30	30	0
Main meals
Pizza	23	Wheat	140	32	100
Refined pasta	40	Wheat	140	0	49a
Whole grain pasta	40	Wheat	140	56	290a
Refined couscous	40	Wheat	140	0	69
Whole grain couscous	40	Wheat	140	56	402
White rice (cooked)	40	Rice	140	0	0
Brown rice (cooked)	40	Rice	140	56	0
Quinoa	40	Quinoa	140	56	58b
Snacks
Biscuit/cookie	22	Wheat	15	3.3	5.6a
Digestive	70 (16% WG)	Wheat	15	2.4	57
Muesli/granola bar	40	Wheat and oats	30	12	49a
Popcorn	100	Corn	30	30	0
Refined wheat cracker	85	Wheat	14	0	16
Whole grain wheat cracker	85	Wheat	14	12	340a

^a Average based on products with the same designation but different amounts of cereal ingredients.

^b Alkylresorcinols only, not including methyl and branched chain alkylresorcinols.

In some countries, it is common practice to add syrup or caramel coloring to give bread a darker appearance, or to add bran, intact grains or seeds in bread dough made from largely white flour to get a bread with good loaf volume and soft texture, but with the appearance of “wholesomeness” (Figure 5.1). This makes it very difficult to judge the whole grain content of bread based on appearances alone. Information on‐pack, or from manufacturers, is necessary to get an accurate measure of the whole grain content of individual breads. In some countries, such as the Netherlands and Germany, there are clear guidelines for labeling bread as whole grain, requiring 90–100% of flour to be whole grain flour,⁽¹⁾ though in other countries, it may be difficult or impossible to determine whole grain content for “dark bread.”

Due to the highly variable nature of bread, and the fact that the use of whole grain flour may be highly specific for different countries or regions, it is necessary to carry out on‐the‐ground surveys of both pre‐packaged bread and bread bought directly from local bakeries to get an idea of whole grain content.