Analytical Characterisation of Oat-Enriched Binary Composites of Wheat Flour and Their Processing Behaviour in Bread Making

Soluble and Insoluble Dietary Fiber Contents of Various Breads, Pastas, and Rye Flours on the Finnish Market, 1990–1991

Influence of nutritional and antinutritional components on dough rheology and in vitro protein & starch digestibility of minor millets

One of the requirements for proper nutrition and maintenance of good health is to supply the body, through diet, with an appropriately increased quantity of bioactive compounds. With this in mind, modern milling and baking industries keep introducing new types of products. The use of such additives as wholegrain flours and bran in baked products provided the basis for research in this paper. The aim of the study was to conduct a qualitative and quantitative evaluation of marketable wheat, barley and oat grain, used as raw materials to produce dehulled kernels, ground grain, wholemeal flour and wheat flour type 550 (all-purpose or plain flour), as well as wheat bran. Additionally, analyses were performed to determine the chemical composition and contents of nutrients, selected bioactive compounds and antioxidant activity. The studied raw materials in commercial cereal differ in their chemical composition. Dehulling of wheat, barley and oat grains significantly contributed to the reduction of minerals, protein and total dietary fiber (TDF) contents, except for the amount of protein in dehulled wheat and oat grains. Oat bran, in contrast to other oat products, was characterized by the highest contents of minerals, protein, TDF, and the smallest amounts of saccharides and total starch. The lowest content of minerals was recorded in wheat flour type 550. Thermal processes affect the concentration of tocochromanols in the grain, with tocotrienols being more resistant to hydrothermal treatment than tocopherols. Grain dehulling also significantly decreased the total amount of tocochromanols in relation to the original grains. Wheat products differ in the contents of their individual components. They are characterized by high contents of tocochromanols, phenolic compounds and water-extractable arabinoxylans, with the exception of white refined wheat flour, which is mainly a source of saccharides. In the case of barley and oat products, the analysis showed no differences between these product groups. It was also shown that dehulling of barley and oat grain causes statistically significant differences in the contents of nutrients and natural antioxidants.

Soluble Oat Fiber Tends to Normalize Lipoprotein Composition in Cholesterol-Fed Rats

Insoluble fiber fractions from raw and extruded oat, rice and wheat brans were isolated and phytate removed. In vitro mineral binding studies were performed utilizing copper (Cu2+), calcium (Ca2+) and zinc (Zn2+) ions, which were added individually to enzymatically treated (Prosky et al., 1985), acid washed insoluble fiber residues from oat, rice and wheat brans. The enzymatic digestion step with alpha-amylase, protease and amyloglucosidase served to remove protein and starch from the samples. Mineral binding studies were performed on the insoluble fiber residue. Mineral content was determined by flame atomic absorption spectroscopy. Raw brans served as controls. A twin-screw extruder Model DNDG-62/20D, manufactured by Bühlerag (CH-9240, Uzwil, Switzerland) was utilized. The objectives of the study were to determine the total Cu2+, Ca2+ and Zn2+ binding capacity of the dephytinized insoluble fiber from each bran; and to determine if extrusion screw speed affected the brans' insoluble fiber mineral binding capacity. Although dephytinized, the brans' insoluble fiber fraction bound Cu2+, Ca2+ and Zn2+ ions. Oat bran bound more Cu2+, Ca2+ and Zn2+ than wheat bran, which bound more than rice bran. Extrusion processing did not affect the brans' insoluble fiber binding capacity to bind Cu2+. However, it increased the binding capacity of Ca2+ and Zn2+ of the insoluble fiber fraction from rice and oat brans.

PurposeThe purpose of this paper is to compare and evaluate for quality characteristics and β‐glucan analysis during different stages of the oat flour and/or oat bran based bread baking process.Design/methodology/approachA 100 per cent wheat flour (WF) formulation was substituted with 30, 50 and 70 per cent oat flour (OF) or oat bran (OB) to improve its nutritional quality characteristics of bread. The flour blends were evaluated for quality characteristics (loaf volume, texture profile analysis) and β‐glucan analysis during different stages of the bread baking process.FindingsA significant decrease in specific volume, number of cells and crumb brightness was observed with increasing WF substitution levels with OF or OB. The crumb hardness was observed to be negatively correlated with specific volume of OF (r =−0.90, p<0.0001) and OB (r =−0.84, p<0.0001) bread. The level of β‐glucan was significantly reduced by 37.8 −42.9 per cent in dough during 45 min fermentation time, which indicating the enzymatic action. The β‐glucan content of OF and OB bread was found to increase from 0.13 g/100 g bread (db) (control) to 1.35 and 3.61 g β‐glucan/100 g bread (db) for 70 per cent WF substitution with OF and OB, respectively. Results show that a bread of acceptable quality can be prepared by substituting WF by up to 50 per cent for OF and up to 30 per cent by OB.Practical implicationsReplacing white bread with oat flour/bran containing β‐glucan facilitates human consumption of soluble dietary fibre.Originality/valueThe paper provides a comparative evaluation of the oat flour and/or bran based bread and its critical factors influencing the level of β‐glucan during baking process, which attributes to improve the nutritional quality.

To determine total dietary fiber (TDF) composition of feline diets used for management of obesity and diabetes mellitus. Cross-sectional survey. Dry veterinary (n = 10), canned veterinary (12), and canned over-the-counter (3) feline diets. Percentage of TDF as insoluble dietary fiber (IDF), high-molecular-weight soluble dietary fiber (HMWSDF), and low-molecular-weight soluble dietary fiber (LMWSDF) was determined. Median measured TDF concentration was greater than reported maximum crude fiber content in dry and canned diets. Median TDF (dry-matter) concentration in dry and canned diets was 12.2% (range, 8.11% to 27.16%) and 13.8% (range, 4.7% to 27.9%), respectively. Dry and canned diets, and diets with and without a source of oligosaccharides in the ingredient list, were not different in energy density or concentrations of TDF, IDF, HMWSDF, or LMWSDF. Similarly, loaf-type (n = 11) and gravy-type (4) canned diets differed only in LMWSDF concentration. Disparities in TDF concentrations among products existed despite a lack of differences among groups. Limited differences in TDF concentration and dietary fiber composition were detected when diets were compared on the basis of carbohydrate concentration. Diets labeled for management of obesity were higher in TDF concentration and lower in energy density than diets for management of diabetes mellitus. Diets provided a range of TDF concentrations with variable concentrations of IDF, HMWSDF, and LMWSDF. Crude fiber concentration was not a reliable indicator of TDF concentration or dietary fiber composition. Because carbohydrate content is calculated as a difference, results suggested that use of crude fiber content would cause overestimation of both carbohydrate and energy content of diets.

The health benefits associated with dietary fiber have resulted in it now being used in virtually all food product categories, including many products which are manufactured using extrusion processing. The objective of the present study was to determine if extrusion processing affected phytic acid, and soluble and insoluble fiber contents. The effect of screw speeds of 50, 70, and 100% of maximum rotations per minute (% MRPM) on these components was investigated. A BI-EX Model DNDG-62/20D co-rotating intermeshing self-cleaning twin-screw extruder, manufactured by Bühlerag, CH-9240, Uzwil, Switzerland, was used to process wheat, oat and rice brans. It was found that extrusion did not affect the insoluble fiber content of wheat bran; however, a decrease in this component was observed in rice and oat brans. The effect on rice bran insoluble fiber was greatest at screw speeds of 50 and 70% MRPM. This occurred in oat bran at 50% MRPM. Soluble fiber content increased in all brans after extrusion, except ER100. For oat and rice bran soluble fibers, the greatest increase occurred at 50 and 70% MRPM, while for wheat bran this occurred at 70 and 100% MRPM. Extrusion did not affect the phytate content of the cereal brans.

The objective of the research study was to determine the effect of wholemeal oat flour storage on changes in a content of total (TDF), soluble (SDF), and insoluble (IDF) dietary fibre and in rheological properties of wholemeal oat flour. The analysis included the flours milled from naked oat grain in a laboratory. Those oat flours were stored for 3 months at temperatures of 20 ºC, 4 ºC and -20 ºC. The apparent viscosity (initial, maximal, final, setback) was determined in 5 % (w/w) water-based suspensions. Regardless of the storage temperature, an increase was reported in the content of IDF as was a decrease in the content of SDF during the 3-month period of storing flour. The widest range of changes in the individual dietary fibre fractions was reported during storage at 20 ºC. The changes in the rheological properties depended on the time and temperature of oat flour storage. The largest changes were reported in the case of the setback value during storage at 20 ºC and 4 ºC. The smallest range of changes in all the rheological properties was found in the flours stored at -20 ºC. During the 3-month period of storing flour the range of changes in the rheological properties was inconsiderable and it did not depend on the contents of individual dietary fibre fractions, therefore it should not have any significant effect on the changes in the technological properties of flours. No unequivocal dependences were reported between the changes in the content of dietary fibre fractions and the rheological properties. During the entire 3-month storage period, the smallest changes occurred in the dietary fibre composition and rheological properties of oat flour during storage at the -20 ºC temperature.

The digestibility of polysaccharides and other major components and the metabolic response of the microflora in the small and large intestines to oat diets varying in mixed linked beta(1-->3; 1-->4)-D-glucan (beta-glucan) were studied in experiments with ileum-cannulated pigs. The oat fractions for diets were prepared in a dry milling process in which oat groats were milled into two endosperm fractions (oat flour 1 and oat flour 2) and oat bran. The digestibility of polysaccharides and the metabolic response of the microflora were followed for the two contrasting diets, oat flour 1 and oat bran, from ingestion to excretion while the digestibility of oat groats and oat flour 2 were estimated only at the ileum and in faeces. There was no degradation of beta-glucan from either oat flour 1 or bran in the stomach and the first, middle and distal thirds of the small intestine (average digestibility approximately 0), while in the terminal ileum digestibility increased to 0.30 to 0.17 respectively. The digestion of starch in the first third of the small intestine was lower for the high-beta-glucan oat-bran diet (0.49) than for the low-beta-glucan flour diet (0.64). However, digestibility differences between the two diets levelled out as the digesta moved aborally in the small intestine and the digestibility at the terminal ileum was almost complete (0.970-0.995) for all diets. Oat non-starch polysaccharides (NSP) were an easily digestible energy source for the microflora in the large intestine less than 13% of dietary NSP being recovered in faeces. The bulk of beta-glucan which survived the small intestine was degraded in the caecum and proximal colon while arabinoxylan was more slowly degraded. The amount of residues passing the ileo-caecal junction has little impact on the density of micro-organisms in the large intestine, which on the flour and bran diets were in the range of 10(10)-10(11) viable counts/g digesta, but a high impact on the activity of the flora in colon. Oat bran resulted in a higher proportion of butyric acid in large intestinal content compared with the flour diet. The faecal bulking effect of oat bran was mainly caused by an increased excretion of protein and fat, presumably of bacterial origin. Of all the diets tested the oat-bran diets had the lowest digestibilities of protein and fat at the terminal ileum and in the faeces.

Total dietary fiber content of polished, brown and bran types of Japonica and Indica rice in Taiwan: Resulting physiological effects of consumption

Abstract. Widyawan MB, Hasanah A, Taryono, Alam T, Sayekti RS, Pramana AAC, Wulandari RA. 2020. Multivariate analysis unravels genetic diversity and relationship between agronomic traits, protein, and dietary fiber in yardlong bean (Vigna unguiculata subsp. sesquipedalis Verdc.). Biodiversitas 21: 5662-5671. Yardlong bean (Vigna unguiculata subsp. sesquipedalis Verdc.) is a vegetable legume that possesses the highest amount of protein and total dietary fiber (TDF) content among other vegetables. However, protein and TDF content diversity are found among yardlong bean genotypes. Genetic improvement to produce cultivars with high yield and improved nutritional content is required. This study aimed to analyze genetic diversity and identify the relationship between important agronomic traits from 21 yardlong bean genotypes assessed by multivariate statistical analysis. The experiment was arranged in alpha design with three replicates, each consist of six blocks. Six pod-related important agronomic traits, protein, and TDF content were observed in this study. Total pod weight, pod weight, and pod length were found to be negatively correlated with protein and TDF content based on correlation and principal component analysis (PCA). Although negatively correlated, several variables possess a large and positive direct effect on protein and TDF content, such as the number of pod, pod weight, and days to flower. D2 analysis and Tocher’s method classify genotypes used in this study into five clusters with diverse traits value. Information from this study laid a foundation for the improvement of important agronomic traits as well as nutritional content in yardlong bean.

Wistar rats (ten per group) were fed either an oat-free control diet or a dietary fibre-rich test diet containing 500 g oat-based products/kg for 6 weeks. The oat-based products, containing 4-128 g/kg resistant starch, 30-92 g/kg beta-glucan and 122-304 g/kg total dietary fibre, were oat flour extrudate, flour/Novelose (commercial resistant starch) extrudate (80:20 w/w), oat bran, bran/Novelose extrudate (80:20 w/w) and autoclaved oat flour. Serum total cholesterol decreased in the groups fed flour, flour/Novelose and bran/Novelose (P<0.05). In most of the test groups, count numbers of bifidobacteria were higher (P<0.001) and of coliforms were lower (P<0.05). The mass of the caecum walls and contents was greater in groups fed Novelose- and bran-containing diets (P<0.005). In all the test groups, pH values were lower in the intestinal contents (P<0.001), and caecal concentrations of acetate (P<0.001), propionate (P<0.05), butyrate (P<0.005) and total SCFA (P<0.001) were higher. The lowest concentrations of steroids were found in rats fed the autoclaved flour. In the other test groups, more bile acids appeared in the caecal (P<0.001) and colonic contents (P<0.005), as well as in the faeces, at week 6 (P<0.001). The highest bile acid excretion was found after feeding bran-containing diets. In the intestinal contents of all the test groups, more primary bile acids (P<0.001) appeared than in the control group. The excretion of steroids increased within the experimental period. Using extrusion technology, dietary fibre-rich oat-based products, which have beneficial physiological effects in rats, can be produced. Oat flour and bran are excellent sources for the preparation of directly edible oat products. Their nutritional properties can be further improved by the addition of resistant starch.

Dietary fibres from cereals are much more used than dietary fibres from fruits; however, dietary fibres from fruits have better quality. In recent years, for economic and environmental reasons, there has been a growing pressure to recover and exploit food wastes. Grape fibre is used to fortify baked goods, because the fibre can lower blood sugar, cut cholesterol and may even prevent colon cancer. Grape pomace is a functional ingredient in bakery goods to increase total phenolic content and dietary fibre in nourishment. The aim of this study was to determine the chemical composition of commercial fibres, obtained from different Grape sources concerning their chemical properties such as moisture, ash, fat, protein, total dietary fibre. The chemical composition of Grape fibre is known to vary depending on the Grape cultivar, growth climates, and processing conditions. The obliged characteristics of the fibre product are: total dietary fibre content above 50%, moisture lower than 9%, low content of lipids, a low energy value and neutral flavour and taste. Grape pomace represents a rich source of various high-value products such as ethanol, tartrates and malates, citric acid, Grape seed oil, hydrocolloids and dietary fibre. Used commercial Grape fibres have as a main characteristic, the high content of total dietary fibre. Amount of total dietary fibre depends on the variety of Grapes. Total dietary fibre content (TDF) in our samples of Grape fibre varied from 56.8% to 83.6%. There were also determined low contents of moisture (below 9%). In the samples of Grape fibre were determined higher amount of protein (8.6 - 10.8%), mineral (1.3 - 3.8%) and fat (2.8 - 8.6%). This fact opens the possibility of using both initial by-products as ingredients in the food industry, due to the effects associated with the high total dietary fibre content.

Dietary fiber rich chicken meat patties were developed by incorporating wheat and oat bran to chicken meat at 5, 10 and 15% levels. Oat bran contained higher amount of soluble dietary fiber (SDF) and unsaturated fatty acids (USFA) than wheat bran, whereas total dietary fiber (TDF), insoluble dietary fiber (IDF) and saturated fatty acids (SFA) were higher in wheat bran. Incorporation of bran significantly increased the water holding capacity (WHC) and emulsion stability (ES). Oat bran showed better effect on WHC and ES than wheat bran. Addition of bran resulted in significant increase in cooking yield, firmness, TDF, USFA and reduction in sensory attributes, moisture, protein, fat and cholesterol content. IDF was higher in wheat bran added patties and SDF and SFA/USFA ratio in oat bran added patties. It is concluded that oat and wheat bran can be incorporated up to 10 and 15% level, respectively for preparation of baked and steamed chicken patties.