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Cereal products are consumed daily by the majority of the population. Popular belief is that these cereal products, rich in carbohydrates, produce a high glycaemic response and may not be a contributing factor to the obesity epidemic throughout the world. Recently the food industry has investigated ways of improving the overall nutritional balance of carbohydrate rich foods and focused on increasing their dietary fibre (DF) contents at the expense of readily digestible carbohydrates. It is well documented that dietary fibre is involved in disease prevention and enhanced health of consumers. Moreover, the food industry can take advantage of the physicochemical properties of fibre to improve the viscosity, texture, sensory characteristics and shelf-life of their products. The focus of this review paper is on the influence of DFs (inulin, fructo-oligofructose, β-glucans, arabinoxylans and resistant starch) supplementation on the quality and nutritional aspects of common foods containing cereals- pasta, bread, muffins/cakes and extruded snacks. This review reports on the evidence regarding fibre enrichment of cereal foods and looks at the advances and future trends in enriched dietary fibre cereal products.

Scanning electron microscopy (SEM) was used to examine a number of good and poor malting quality barley cultivars of both spring- and winter-sown type. Mature grains were frozen and fractured, and the endosperm surfaces were examined, with particular attention given to the sub-aleurone and starchy endosperm regions. All of the cultivars showed similar patterns of endosperm cell size, distribution and packing. However, variation in the patterns of fracture through the endosperm, and in the extent of starch–protein adhesion, were observed. Poor malting quality cultivars had fracture planes that traversed the starch granule—protein matrix interface, indicating a high degree of starch–protein association similar to that exhibited by hard wheat cultivars. In contrast, good malting quality cultivars had fracture planes around the starch granules, indicating a low degree of starch–protein binding similar to that exhibited by soft wheat cultivars. The possible role of starch–protein binding in malting performance is discussed.

Microscopy and in vitro digestibility methods were used to obtain information about the putative inhibitory effect of guar gum, an endospermic seed extract, on the rate of digestion of wheat bread starch. Guar seed endosperm was examined by bright field microscopy after staining with toluidine blue or ruthenium red, by epifluorescence microscopy after labelling with two fluorescein-labelled lectins specific for α- D -galactose and D -mannose residues, respectively, and by scanning electron microscopy (SEM). These methods showed that guar galactomannan, the main component of guar gum, was located both within the plant cell walls and as amorphous deposits within the cell vacuole. SEM examination showed that the latter persisted in the milled guar flour. Examination of wheat bread containing guar gum by SEM and by fluorescence microscopy using the labelled lectins revealed that the starch granules and surrounding bread matrix were coated with a layer of galactomannan mucilage. After guar bread was ingested by pigs, the close association of galactomannan with the wheat starch persisted during the early post-prandial period (0–90 min), but this was greatly reduced at later post-prandial times (≥180 min). The in vitro hydrolysis of starch in guar bread was found to be attenuated significantly compared with normal wheat bread. The results are consistent, therefore, with the concept that guar galactomannan acts as a physical ‘barrier’ to alpha -amylase–starch interactions and/or subsequent release of hydrolysed products (e.g. maltose). Such a process, in addition to the effect of guar gum on digesta viscosity, may be significant in reducing the rise in post-prandial glycaemia caused by guar gum in humans.

β-glucan is a commonly researched plant cell wall component that when incorporated into food products has been associated with cholesterol and glycaemic response reductions. This study focusses on β-glucan rich fractions from barley and mushroom used in the production of extruded ready to eat snacks. Inclusion of barley β-glucan rich fractions and mushroom β-glucan fractions at 10 % levels increased the total dietary fibre content of extrudates compared to the control (P

Esterification is one of the most important methods to alter the structure of starch granules and improve its applications. Conventionally, starch esters are prepared by conventional or dual modification techniques, which have the disadvantages of being expensive, have regent overdoses, and are time-consuming. In addition, the degree of substitution (DS) is often considered as the primary factor in view of its contribution to estimate substituted groups of starch esters. In order to improve the detection accuracy and production efficiency, different detection techniques, including titration, nuclear magnetic resonance (NMR), Fourier transform infrared spectroscopy (FT-IR), thermal gravimetric analysis/infrared spectroscopy (TGA/IR) and headspace gas chromatography (HS-GC), have been developed for DS. This paper gives a comprehensive overview on the recent advances in DS analysis and starch esterification techniques. Additionally, the advantages, limitations, some perspectives on future trends of these techniques and the applications of their derivatives in the food industry are also presented.

International audience; Three non‐traditional pseudo‐cereal flours (amaranth, buckwheat and millet) were used in the manufacture of extruded breakfast cereal products as a replacement for wheat and maize flour. The use of these flours altered the physical and nutritional quality of extruded breakfast cereals. Extruded products made using the flours exhibited an increased product and bulk density. However the extruded products were not significantly different compared to the control sample in terms of expansion ratio (excepting Amaranth at the 65% inclusion rate). All of the extruded products made with the inclusion of pseudo‐cereals showed a significant reduction in readily digestible carbohydrates and slowly digestible carbohydrates compared to the control product during predictive in vitro glycaemic profiling. The results illustrate the potential use of these non‐traditional cereal flours in lowering the glycaemic response to the ingestion of extruded breakfast cereals.

The iron-rich bread (2.2 mg iron per 50 g slice) used in the study was developed using Eragrostis tef flour, naturally rich in iron. Iron deficiency is prevalent in pregnancy and compliance with supplements can be low. In this double-blind, randomized trial 34 Caucasian, primiparous antenatal patients were randomized to receive intervention bread or a placebo for 6 weeks. Women consumed on an average of 2.3 slices per day, providing a total of 5.0 mg iron. Using World Health Organisation (2001) haemoglobin cut-offs, 12% of participants eating the iron-rich bread were iron deficient by the end of the study compared with 27% in the control group. For other markers of iron status, these were improved in the placebo versus the treatment group. For example, a significant decline in serum iron and transferrin saturation was not observed in this group. Findings demonstrate that other modes of delivery, i.e. food fortification, may be needed to generate 'physiological effects', or further measures are taken to improve intervention compliance.

The effects of Celluclast 1.5L concentration on the physicochemical characterization of gold kiwifruit pectin was evaluated. Varying the enzyme concentration affected the pectin yield and pectin physicochemical properties. The viscosity of extracted pectin was largely dependent on the enzyme concentration. Celluclast 1.5L with medium concentration exhibited the highest viscosity. Varying the enzyme concentration also influenced the molecular weight distribution. High molecular weight (M(w)) pectin (1.65 × 10(6) g/mol) was obtained when the medium concentration was used. Overall, the study clearly reflects the importance of taking into consideration the amount of cellulytic enzyme added in order to determine the final quality of pectin.

Material was produced from Crown pumpkin (Cucurbita maxima) processed from fractions of the fruit which are regarded as waste stream products (peel, flesh and seed). The flour from the three different fractions (peel, flesh and seed) of Crown pumpkin flour was incorporated into an extruded snack product formulation at levels 10%, 30% and 50% (w/w with corn grit) and processed in a twin-screw extruder to make 10 expanded snack products. Proximate analysis was carried out to determine the nutritional value of the raw pumpkin and pumpkin flour. A physical analysis of the product was used to determine its color, the expansion ratio, bulk density and texture. Inclusion of waste stream material (peel and seed) at 10%, yielded extruded products with similar expansion and density characteristics to the control sample; however, an inclusion of greater than 10% yielded significant challenges to product quality (hardness of the product).

This chapter explains nonstarch polysaccharides (NSPs), which are the major part of dietary fiber (DF) and includes cellulose, pectins, glucans, gums, mucilages, inulin, and chitin. NSPs are the principal components of the plant cell wall and constitute a major source of fiber in the diet. They are classified into soluble and insoluble fractions. The insoluble fraction of NSP is normally found on the outer protective layer of plants, whereas soluble NSP is normally found in the inner parts of plants The key aspect of NSPs is that they are plant materials that are not digested by the enzymes of the human digestive tract but remain fermentable in the large intestine. NSPs are the principal components of dietary fiber and the lack of small intestinal digestibility explains the majority of their principal physiological properties. The physicochemical properties of NSPs result in a number of physiological effects that are related to certain health benefits. They are claimed to modulate blood glucose and insulin responses to foods to lower blood cholesterol and to have beneficial effects on the prevention and treatment of certain diseases like gallstones, diverticular disease, obesity, constipation, or colon cancer.

Ozone is an effective fumigant for insect killing, mycotoxin destruction and microbial inactivation which has a minimal or no effect on grain quality. Studies have demonstrated that ozone which is a natural agent, may offer unique advantages for grain processing along with addressing growing concerns over the use of harmful pesticides. This paper focuses on the efficacy of ozone for preservation of food grains and discusses the possible effects on product quality. Inactivation mechanisms for micro-organisms and mycotoxins are detailed. Critical intrinsic and extrinsic factors governing inactivation are discussed along with potential grain applications.

Publisher Summary The convenience of pasta in terms of consumer preparation and the relatively uncomplicated ingredient formulation and processing conditions required for the manufacture of pasta, mean that pasta is an excellent model food system and vehicle for the inclusion of Dietary Fibers (DF). Although this inclusion is associated with problems in relation to cooking characteristics and the texture of pasta, it provides a tangible opportunity to develop nutritious, fiber-rich, carbohydrate-rich but Glycaemic Index (GI)-low food products, suitable for the health-conscious consumer. This chapter explores some of the work conducted on fiber addition to pasta and its implications in terms of food structure and function. The specific relationship between fiber ingredients and the reduction in GI has to be established on a fiber by fiber basis as generalizations can be made that may not necessarily hold true when further verification is attempted. However, the incorporation of fiber into pasta can enhance its appeal as a food product rich in slowly digestible carbohydrates. It is possible, therefore, to use fiber enrichment of pasta to manipulate energy intake and weight gain and possibly to have an effect on the perception of satiety. Dietary fiber is just one such ingredient that has the potential to alter the water-holding capacity of a product and compete for water with protein and starch during dough development. Thus, much attention has been focused recently on the incorporation of dietary fiber ingredients into pasta.

Regulation of dietary carbohydrates is used in the control of glycaemia and hence diabetes. An individuals glycaemic response varies depending on food source. To address the differences between foods in their effect on postprandial glycaemia, the concept of glycaemic index (GI) was introduced as a tool for classifying foods based on their blood glucose raising potential. High fibre foods have been suggested as important in modulating GI. Mechanisms suggested range from, reduction of alpha amylase accessibility, to modification of intestinal events such as gastric emptying and intestinal absorption. This study focused on how a range of dietary fibres (varying in degrees of solubility) affects the structure of cereal products (breads, biscuits and pastas) and hence their nutritional characteristics. In vitro and in vivo digestion procedures were used to determine the potential and posprandial glycaemic responses. The results obtained suggest that by dietary fibre inclusion, the digestibility of the cereal products can be decreased. The percentage of GI decrease depended upon the type of dietary fibre used in the recipe and also on the level of addition. In vitro results were closely correlated to in vivo determinations.

There is one commodity the world over that unites mankind—food. In 2011 the United Nations claimed that the world’s population had reached the seven billion mark, a number which is set to increase dramatically in the decades to come. Food security, supply and sustainability are of paramount concern to the future economic and social progress of humanity. It is the responsibility of the food industry, together with food scientists and technologists, to shoulder the burden of ensuring an adequate supply of nutritious, safe and sensorially acceptable foods for a range of demanding consumers. In responding to this challenge, we need to understand the link between agriculture, engineering, food processing, molecular biosciences, human nutrition, commercialisation and innovation. Access to information concerning the composition and quality of foods has never been so easy for consumers and technologists alike. A plethora of research publications are made available each month to scientists and associated interested parties. The outcomes of these research manuscripts are often distilled and disseminated into messages available to everyone through bulletin boards, forums and the popular press. Newspapers and new agencies constantly report on the latest pharma-medical finding, or news regarding food safety and security concerns. We live in an age where information is so readily available to everyone that the task of finding credible and reputable data can be difficult at times. Providing sound evidenced based research is where a peer-reviewed journal can provide clarity. [...]

Winter- and spring-sown barley cultivars of good- and poor-malting quality were micro-malted and samples taken at different stages of the process. Histochemical and biochemical techniques were used to examine changes in total protein, cell walls, carbohydrate reserves and the patterns and extent of grain modification. No differences were observed in the general patterns of protein distribution between mature grains of the various cultivars. In all cases the initial utilisation of the protein reserves was first observed in the sub-aleurone layer of the endosperm, with subsequent modification gradually progressing further into the grain. Differences in the patterns of grain modification were observed, with good-malting cultivars demonstrating faster and more uniform breakdown of cell walls and digestion of endosperm reserves than poor-malting cultivars. These differences cannot be explained by variation in levels of alpha- amylase or β- glucanase; the good and poor quality cultivars examined showed similar levels of extractable activity from malted grains.