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Whole grain consumption has been linked to a lower risk of metabolic syndrome, which is normally associated with a low-grade chronic inflammation. The benefits of whole grain are in part related to the inclusion of the bran, rich in phenolic acids and fiber. However, the phenols are poorly bioaccessible from the cereal matrix. The aim of the present study was to investigate the effect of bioprocessing of the bran in whole wheat bread on the bioavailability of phenolic acids, the postprandial plasma antioxidant capacity, and ex vivo antiinflammatory properties. After consumption of a low phenolic acid diet for 3 d and overnight fasting, 8 healthy men consumed 300 g of whole wheat bread containing native bran (control bread) or bioprocessed bran (bioprocessed bread) in a cross-over design. Urine and blood samples were collected for 24 h to analyze the phenolic acids and metabolites. Trolox equivalent antioxidant capacity was measured in plasma. Cytokines were measured in blood after ex vivo stimulation with LPS. The bioavailabilities of ferulic acid, vanillic acid, sinapic acid, and 3,4-dimethoxybenzoic acid from the bioprocessed bread were 2- to 3-fold those from the control bread. Phenylpropionic acid and 3-hydroxyphenylpropionic acid were the main colonic metabolites of the nonbioaccessible phenols. The ratios of pro-:antiinflammatory cytokines were significantly lower in LPS-stimulated blood after the consumption of the bioprocessed bread. In conclusion, bioprocessing can remarkably increase the bioavailability of phenolic acids and their circulating metabolites, compounds which have immunomodulatory effects ex vivo. [ABSTRACT FROM AUTHOR]

Background and aims: Whole-grain cereals and diets with a low glycemic index may protect against the development of type 2 diabetes and heart disease, but the mechanisms are poorly understood. We studied the effect of carbohydrate modification on serum metabolic profiles, including lipids and branched chain amino acids, and dependencies between these and specific gene expression pathways in adipose tissue. Methods and results: Twenty subjects with metabolic syndrome were selected from the larger FUNGENUT study population, randomized either to a diet high in oat and wheat bread and potato (OWP) or rye bread and pasta (RP). Serum metabolomics analyses were performed using ultra-performance liquid chromatography coupled to electrospray ionization mass spectrometry (UPLC/MS), gas chromatography (GC) and UPLC. In the OWP group multiple proinflammatory lysophosphatidylcholines increased, while in the RP group docosahexaenoic acid (DHA 22:6n-3) increased and isoleucine decreased. mRNA expression of stress reactions- and adipose tissue differentiation-related genes were up-regulated in adipose tissue in the OWP group. In the RP group, however, pathways related to stress reactions and insulin signaling and energy metabolism were down-regulated. The lipid profiles had the strongest association with the changes in the adipose tissue differentiation pathway when using the elastic net regression model of the lipidomic profiles on selected pathways. Conclusion: Our results suggest that the dietary carbohydrate modification alters the serum metabolic profile, especially in lysoPC species, and may, thus, contribute to proinflammatory processes which in turn promote adverse changes in insulin and glucose metabolism. [Copyright &y& Elsevier]

Cereal fiber may reduce the risk of colorectal cancer by diluting colonic contents due to increased fecal output, by accelerating intestinal transit, by increasing fecal frequency and by altering bacterial metabolism. The effects of whole-meal rye bread on some putative colon cancer risk markers were investigated in 17 healthy Finnish subjects using a randomized crossover trial with two 4-wk bread consumption periods and a 4-wk washout period between the bread periods. White wheat bread was used as a control. Test breads covered a minimum of 20% of the daily energy intake (range, 4330-14, 033 kJ/d). Intestinal transit time, stool weight, fecal bacterial enzyme activities and short-chain fatty acid, ammonia, diacylglycerol (DAG) and bile acid concentrations in feces (expressed per gram wet feces) were measured. Whole-meal rye bread significantly increased fecal output and fecal frequency and shortened mean intestinal transit time compared with wheat bread in both women and men. Activities of beta-glucuronidase and beta-glucosidase (expressed per gram wet feces) were significantly lower in men and urease activity significantly higher in women during the rye bread period (RBP). Fecal butyrate concentration was higher during the RBP in men. Fecal ammonia and DAG concentrations did not differ between bread periods. Fecal total and secondary bile acid concentrations were significantly lower during RBP in both women and men. This study shows that whole-meal rye bread significantly improves bowel function in healthy adults and may decrease the concentration of some compounds that are putative colon cancer risk markers. [ABSTRACT FROM AUTHOR]

The objective of this study was to determine the hypocholesterolemic effects of whole meal rye and white wheat breads in healthy humans with elevated serum cholesterol concentrations, and the changes in plasma glucose and insulin concentrations during rye and wheat bread periods. The subjects were 18 men and 22 women with baseline serum cholesterol concentration of 6.4+/-0.2 mmol/L. The study design was a 2x4-wk crossover trial during which each subject randomly consumed rye and wheat breads (20% of daily energy) as part of their usual diet for 4 wk. The bread periods were separated by a 4-wk washout period. Blood samples (after fasting) were collected on two consecutive days at the beginning and end of the bread periods. Serum total cholesterol decreased by 8% (P = 0.002) in men but was not significantly altered in women during the rye bread period. The wheat bread period did not affect any of the variables studied. Analysis of the serum lipids in tertiles of rye bread consumption confirmed the reduction in total cholesterol (P = 0.048) in men and revealed the reduction in LDL cholesterol (P = 0.032); both were dependent on the amount of rye bread consumed (-2, -14 and -10% in total cholesterol and 0, -12 and -12% in LDL cholesterol). Neither rye nor wheat bread influenced the concentrations of glucose and insulin. In conclusion, rye bread is effective in reducing serum total and LDL cholesterol concentrations in men with elevated serum cholesterol. Good compliance with consuming a relatively large amount of rye bread in the usual diet indicates that rye bread offers a practical dietary means of reducing serum cholesterol in men. [ABSTRACT FROM AUTHOR]

Background Wholegrain foods are known to be health-beneficial but their sensory characteristics may be a limiting factor for consumption. The scientific literature of factors influencing sensory quality of wholegrain foods is rather scarce. Scope and approach Many cereals like rye, oats, barley and sorghum are actually used mainly as wholegrain, whereas for wheat the situation is the opposite. This review deals with factors that differentiate the sensory properties of wholegrain and bran-rich foods from those of refined cereal foods. Key findings and conclusions Wholegrain and bran contain flavour-active compounds, flavour precursors and resistant cell wall structures causing changes in flavour and texture during processing. In wholegrain foods, different chemical constituents contribute to bitterness. Increased knowledge on flavour formation has led to the possibility to not only measure but actually also design the flavour. Structure and texture are also important determinants underlying eating quality and stability of cereal foods. Hitherto established means of modulating sensory quality and thus improving acceptability of wholegrain foods are presented. [ABSTRACT FROM AUTHOR]

Electrostatic separation was studied in a dry fractionation diagram to obtain β-glucan-enriched fractions from oat bran preparations. Ultra-fine grinding at ambient or cryogenic temperature was needed to achieve good dissociation between the macronutrients of oat bran particles. Particles rich in β-glucan and starch were by electrostatic separation separated from particles rich in arabinoxylan. β-Glucan was only little enriched in the non-defatted bran fractions from 19.6 to 25.0%. In contrast, preliminary defatting by super critical carbon dioxide significantly improved the dissociation of particles during grinding and allowed enrichment of β-glucan to 42.2 or 48.4% after one or two successive electrostatic separation steps. The twice separated positive fraction, containing 48.4% β-glucan, was further fractionated by a combination of jet-milling and air classification, yielding up to 56.2% β-glucan concentration. The results point out the good potential of using electrostatic separation as a bran-fractionation method to produce nutritionally interesting food ingredients. Industrial relevance Oat β-glucan has a widely accepted health claim related to cholesterol lowering, and has a great industrial applicability in functional foods and nutraceuticals. The high concentrations of β-glucan obtained with defatted material are of major interest from an industrial point of view, since this kind of ingredients can be used in applications where normal oat bran preparations cannot provide β-glucan at high enough concentration. In addition, the obtained β-glucan fractions retained their original molecular weight. The high β-glucan fractions had an appealing white colour and were well solubilised in hot water and in 0.1 M NaOH compared to their low β-glucan counter-fractions. Supercritical carbon dioxide extraction is a relatively costly method due to the long processing time (several hours per batch), but there are existing factories offering contract manufacturing. Lipid extraction and fractionation process can be economically feasible, especially when the fractions obtained are used in high-value applications. Ultra-fine grinding and electrostatic separation are energy intensive methods, but they enable enrichment of components without any liquids or solvents. These methods can be used to produce unique fractions which are not possible to obtain with conventional fractionation methods such as sieving and air classification. [ABSTRACT FROM AUTHOR]

Abstract: Caffeic acid and its esters, chlorogenic and caftaric acids, are major dietary polyphenols present in various foods and beverages. Although caffeic acid is easily absorbed in the small intestine, its esterification with quinic acid, as in chlorogenic acid, decreases its gut absorption and increases the quantities reaching the colon and its microbiota. The microbial conversion of caftaric acid, the tartaric acid ester of caffeic acid, has not been studied earlier. In this work we compared the direct action of a human faecal microbiota on the metabolism of caffeic, chlorogenic and caftaric acids in an in vitro fermentation model. All substrates disappeared quickly and none of the free acids (caffeic, quinic or tartaric acids) were detected after 2 hours of incubation. Two major microbial metabolites were identified by HPLC–ESI–MS–MS as 3-hydroxyphenylpropionic (3-HPP) and benzoic acids (BA). Maximal levels of 3-HPP were reached after 2 h of fermentation and accounted for 9–24% of the dose of caffeic acid and its esters. BA was formed steadily throughout the incubation, accounting for 4–5% of the initial dose of the substrates after 24 h of incubation. The similarities in the metabolic patterns observed for caffeic, chlorogenic and caftaric acids suggest that esterification does not influence the metabolism of caffeic acid by the gut microbiota. [Copyright &y& Elsevier]

Sourdough fermentation has a well-established role in improving flavour and structure of bread. However, the significant potential of sourdough fermentation to improve the nutritional properties of rye, oat and wheat products has gained much less attention, although the interest is at present increasing. Sourdough fermentation can modify healthiness of cereals in a number of ways: it can improve texture and palatability of whole grain, fibre-rich or gluten-free products, stabilise or increase levels of various bioactive compounds, retard starch bioavailability (low glyceamic index products) and improve mineral bioavailability. Many new interesting applications for sourdough remain still to be explored, such as the use of prebiotic starter cultures or production of totally new types of bioactive compounds. [Copyright &y& Elsevier]

Microbial reactions in the gut have an essential role not only in gut health, but in general human health. The gut is the site of active fermentation of non-digestible diet components, as well as bioconversions and absorption of plant-derived compounds, such as phenolics. When developing nutritionally designed foods that promote health through gut microbial reactions, three different types of food ingredients can be used: living micro-organisms (probiotics), non-digestible carbohydrates (dietary fiber and prebiotics) and bioactive plant secondary metabolites (e.g. phenolics). [Copyright &y& Elsevier]

The potential to reduce GHG emissions and land use of the diet by replacing animal-based protein sources with foods containing oat protein concentrate (OPC) was analysed by life cycle assessment (LCA) of six different scenarios of daily food intake of one adult. The OPC was used in the preparation of bread and pasta and as a substitute for milk in yoghurt resulting in a higher protein content of these foods. The present study showed, that dietary-related GHG emissions and land use can be reduced by substituting animal-based proteins by foods containing oat protein. If the oat protein (OPC) enriched food items substitute animal based protein sources in the diet proportionally, GHG emission from the diet could be reduced by 8% and land use by 14%. However, if the OPC enriched food items are used specifically to replace intake of all beef and some pork, GHG emissions from the diet could be reduced by 13% and land use by 26%. Thereby, use of new plant-based protein ingredients in diets has a considerable potential to mitigate climate change and reduce land use. Even though the presented scenarios are extreme, they clearly demonstrate the potential that OPC food products made it possible to replace some of the animal-based protein with this plant-based protein source. • Oat protein concentrate (OPC) can be used to increase protein content of e.g. bread, pasta and to make oat yogurt. • Foods containing OPC provide extra protein to diets, and intake of animal-based foods can be reduced. • If intake of all beef and some pork are replaced by foods containing OPC, GHG emissions from the diet could be reduced by 13% and land use by 26%. • If 24% of animal-based food is replaced by OPC food, GHG emission from the diet could be reduced by 8% and land use by 14%. [ABSTRACT FROM AUTHOR]