Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Bread”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 253 records · Page 14Linked to original sources

Developments in bread-making processes.

An introduction to the evolutionary history of wheat is followed by a description of the origin and distribution of the modern hexaploid wheat varieties in Europe. Next, the influence of cultural (the way of bread making), social and economic (i.e. the great influence of the United States and Canada) factors on wheat growing in Europe are considered (Section 1). The anatomy and chemical composition of wheat grains and the fundamental differences between hard and soft wheat are described in Section 2. The process of flour making is treated in Section 3. Section 4 contains a study of gluten proteins and wheat starches in relation to the making of bread (Section 5) and of other wheat products (Section 6). Section 7 deals with the genetic bread-wheat properties: grain hardness, milling quality, production of (unwanted) sticky doughs, alpha-amylase levels, and contains an extensive study of genetics and the role of gliadins and glutenins. A concluding section contains the description and evaluation of assay methods to identify the characteristics of bread wheats for the use of millers, arbiters, and especially for growers.

Animals↗

Bioavailability of elemental iron powder in white wheat bread.

OBJECTIVE: Iron fortification of wheat flour is widely used. In most cases, elemental iron powders are utilized as fortificants due to their lower cost and few, if any, sensory problems. However, their bioavailability is unknown. We aimed to measure the bioavailability of H(2)-reduced elemental iron powder in white wheat bread made from 72% extraction flour. DESIGN: A stable isotope of H(2)-reduced iron powder (mean particle size 15 microm) was used as fortificant in bread prepared from unfortified wheat flour. In all, 12 5- to 7-y-old children were fed bread with 4 mg of H(2)-reduced (58)Fe /100 g of flour. The next day (57)Fe ascorbate was given as reference dose. After 14 days, erythrocytes were analyzed for isotopic enrichment using mass spectrometry. RESULTS: When normalized to 40% absorption of the reference dose, the geometric mean (+/-range of 1 s.d.) bioavailability of reduced (58)Fe in wheat bread rolls was 6.5% (3.7-11.8). CONCLUSIONS: When compared to previous radioiron studies of ferrous sulfate showing 10% absorption from an identical meal in adult women, the relative bioavailability can be estimated at about 65%. However, the bioavailability of this smaller particle size (58)Fe (15 microm) is likely to be higher than that of commercial iron powder (45 microm) although the precise difference cannot be ascertained with current methods. Thus, the bioavailability of commercial elemental iron powders currently used in fortification programs is likely to be substantially lower than that of ferrous sulfate. SPONSORSHIP: This work was funded in part by Grant No 910313 by Micronutrient Initiative, IDRC, Ottawa, Canada.

Biological Availability↗

Palatability and glucose, insulin and satiety responses of chickpea flour and extruded chickpea flour bread eaten as part of a breakfast.

OBJECTIVE: To determine the effect of adding chickpea flour or extruded chickpea flour to white bread on palatability and postprandial glycaemia, insulinaemia and satiety. DESIGN: A randomised, single-blind, cross-over study of four 50 g available carbohydrate breakfasts. SETTING: School of Exercise and Nutrition Sciences, Deakin University. SUBJECTS: In all, 12 healthy subjects were recruited through posted notices. Totally, 11 (nine male, two female) completed the study (mean+/-s.e.m.; age 32+/-2 y; body mass index, 24.7+/-0.8 kg/m(2)). INTERVENTION: After overnight fasting, subjects consumed a control (white) bread (WB) breakfast twice, a chickpea bread (CHB) breakfast once and an extruded chickpea bread (EXB) breakfast once. Palatability and postprandial blood glucose, insulin and satiety responses were determined. Following this, food intakes from an ad libitum buffet and for the remainder of the day were assessed. RESULTS: A trend towards a lower incremental area under the curve (IAUC) of glucose for the CHB breakfast compared to the WB breakfast was observed (P=0.087). The IAUC of insulin and insulinaemic index (II) of the CHB breakfast were higher (P<0.05) than for the WB breakfast. No differences in glycaemic index (GI), satiety response, food intake or palatability were observed. CONCLUSIONS: CHB and EXB demonstrated acceptable palatability. CHB demonstrated some hypoglycaemic effect compared to WB, but neither CHB nor EXB demonstrated effects on satiety or food intake. The hyperinsulinaemic effect of CHB observed in this study requires further investigation.

Adult↗

Vinegar supplementation lowers glucose and insulin responses and increases satiety after a bread meal in healthy subjects.

OBJECTIVE: To investigate the potential of acetic acid supplementation as a means of lowering the glycaemic index (GI) of a bread meal, and to evaluate the possible dose-response effect on postprandial glycaemia, insulinaemia and satiety. SUBJECTS AND SETTING: In all, 12 healthy volunteers participated and the tests were performed at Applied Nutrition and Food Chemistry, Lund University, Sweden. INTERVENTION: Three levels of vinegar (18, 23 and 28 mmol acetic acid) were served with a portion of white wheat bread containing 50 g available carbohydrates as breakfast in randomized order after an overnight fast. Bread served without vinegar was used as a reference meal. Blood samples were taken during 120 min for analysis of glucose and insulin. Satiety was measured with a subjective rating scale. RESULTS: A significant dose-response relation was seen at 30 min for blood glucose and serum insulin responses; the higher the acetic acid level, the lower the metabolic responses. Furthermore, the rating of satiety was directly related to the acetic acid level. Compared with the reference meal, the highest level of vinegar significantly lowered the blood glucose response at 30 and 45 min, the insulin response at 15 and 30 min as well as increased the satiety score at 30, 90 and 120 min postprandially. The low and intermediate levels of vinegar also lowered the 30 min glucose and the 15 min insulin responses significantly compared with the reference meal. When GI and II (insulinaemic indices) were calculated using the 90 min incremental area, a significant lowering was found for the highest amount of acetic acid, although the corresponding values calculated at 120 min did not differ from the reference meal. CONCLUSION: Supplementation of a meal based on white wheat bread with vinegar reduced postprandial responses of blood glucose and insulin, and increased the subjective rating of satiety. There was an inverse dose-response relation between the level of acetic acid and glucose and insulin responses and a linear dose-response relation between acetic acid and satiety rating. The results indicate an interesting potential of fermented and pickled products containing acetic acid.

Acetic Acid↗

Interactions between forms of fat consumption and restaurant bread consumption.

How does fat consumption influence the consumption of companion foods such as bread? Adult restaurant goers who were randomly given olive oil for their bread used 26% more oil on each piece of bread compared to those who were given block butter, but they ended up eating 23% less bread in total. This finding illustrates one way in which fat intake can interact with the consumption of companion foods.

Adult↗

Bread enriched with microencapsulated tuna oil increases plasma docosahexaenoic acid and total omega-3 fatty acids in humans.

The aim of this study was to determine the acute and chronic effects of low doses of long chain (LC) n-3 polyunsaturated fatty acids (PUFA) (<100 mg per day) on plasma LC n-3 PUFA levels using a novel delivery form; bread containing microencapsulated tuna oil (MTO). Six omnivores (three men and three women) participated in the acute study, which involved ingesting a prototype MTO bread containing approximately 80 mg of LC n-3 PUFA/four slices. Plasma triacylglycerol fatty acid compositions were measured after an overnight fast and postprandially at 2 and 4 h. In the chronic study, 10 vegetarian subjects (nine men and one woman) consumed MTO bread at six to eight slices/day (comprising 60 mg of LC n-3 PUFA) as the only dietary source of these PUFA for three weeks. Fasting plasma total and phospholipid fatty acid compositions were measured at baseline and endpoint. In the acute study, the proportions of 22:6 n-3 and total n-3 PUFA in plasma triacylglycerol were significantly increased (P < 0.05). In the chronic study, the proportions of 20:5 n-3, 22:5 n-3, 22:6 n-3, total n-3 PUFA in plasma, and 22:6 n-3 and total n-3 PUFA in plasma phospholipid fractions were significantly increased (P < 0.05) at the endpoint compared with the baseline. This study showed that a low dose of LC n-3 PUFA, consumed as MTO-enriched bread, was bioavailable, as measured by an increase in LC n-3 PUFA levels in the plasma of human subjects.

Adult↗

Complex carbohydrate digestion and large bowel fermentation in rats given wholemeal bread and cooked haricot beans (Phaseolus vulgaris) fed in mixed diets.

The digestion of non-starch polysaccharides (NSP) and of resistant starch (RS) by rats fed on wholemeal-bread-based diets containing 0-450 g cooked, freeze-dried haricot beans (Phaseolus vulgaris)/kg diet was measured over the final 14 d of a 21 d feeding experiment. The bread and beans provided all the dietary polysaccharide. RS could not be detected consistently in faeces and it was assumed that this fraction was entirely fermented in the large bowel (LB). NSP digestibilities were 0.56 and 0.86 for wholemeal bread and beans respectively with no evidence that the dietary presence of beans affected digestibility of bread NSP. Bean non-cellulosic polysaccharides were highly digestible with values of 0.98, 0.88 and 0.99 for arabinose, xylose and uronic acids components respectively. There were large increases in organic matter flow to the LB when beans were fed which was associated with marked caecal hypertrophy and alterations in caecal volatile fatty acids (VFA) pattern. Calculated VFA absorption from the LB was 5-fold higher with the highest level of beans and this was reflected in higher concentrations of VFA in portal and heart blood.

Animals↗

Assessment of the risk of physical contamination of bread packaged in perforated oriented polypropylene films: measurements, procedures and results.

Perforated films used for wrapping factory-manufactured bread must permit a very rapid and intense moisture exchange because the packaging operation is carried out while the bread is still warm (about 80 degrees C) and releasing a high quantity of moisture. The open surface of the wrapping of those products sold in self-service retail outlets generates suspicion about possible contamination of bread not properly handled by the consumers and a better knowledge of the performance of these materials seems appropriate. Using two different approaches, the geometrical characteristics and perforation pattern of 13 different oriented polypropylene (OPP) films representative of the whole European market were assessed objectively. All the measured parameters (density of perforation, hole dimension, open surface, etc.) showed asymmetric distributions, i.e. with averages close to the lowest figures. Similar asymmetric distribution was shown from the 'risk of contamination' by artificial sweat and saliva: an empirical parameter which was measured by procedures developed to simulate the worst possible case of inappropriate manipulation of the packed bread. Good correlation was found between the 'risk of contamination' and both the 'hole surface' (mm(2)) and the 'open surface' (percentage holes surface/film surface), leading to the conclusion that the proposed procedures could represent useful methodologies for assessment of such a particular case of possible food contamination.

Bread↗

Fate of ochratoxin A in the processing of whole wheat grains during milling and bread production.

Batches of whole wheat contaminated with ochratoxin A were produced by inoculation with Penicillium verrucosum under controlled conditions in the laboratory. The fate of ochratoxin was followed through initial cleaning, abrasive scouring of the outer grain coat, milling into wholemeal wheat or into 10 milled fractions. Bread was baked from both wholemeal flour and straight-run white flour. Concentrations of ochratoxin A in the cleanings, scourings, and the bran and offal fractions were increased, but reduced in the white flour. Scouring removed up to 44% of the ochratoxin A present, but only a small further loss occurred in the bread-making process. An overall reduction of about 75% could be achieved in white bread using a combination of cleaning scouring and removal of the bran and offal fractions. Maximum overall reduction in producing wholemeal bread was about 40%. The reduction in ochratoxin A that can be achieved must be considered in relation to economic constraints concerning the disposal of wasted grain. Appropriate strategies for the use or disposal of potentially highly contaminated cleanings, scourings, bran or offal must be established.

Bread↗

Analytical methods for the determination of sterigmatocystin in cheese, bread and corn products using HPLC with atmospheric pressure ionization mass spectrometric detection.

Methods have been developed for the determination of sterigmatocystin in bread, maize and cheese using HPLC linked to mass spectrometry (MS) atmospheric pressure chemical ionization for detection and concurrent confirmation of sterigmatocystin at levels down to less than 5 micrograms/kg. Candidate extraction methods were initially checked for recovery and reproducibility by spiking commodities at a level of 200 micrograms/kg of sterigmatocystin and using HPLC with post-column derivatization. Recovery was found to be greater than 90% for bread and maize, and 75% for cheese. Mass spectrometer conditions for detecting sterigmatocystin were established by injecting solutions directly into the mass spectrometer. Extracts of bread, maize grits and cheese prepared by the candidate extraction methods were examined using HPLC/MS using samples spiked at a level of 20 micrograms/kg of sterigmatocystin. Results for bread and maize samples showed that the extraction procedure recovered more than 90% of added sterigmatocystin and produced extracts free of interference from co-extractives, with limits of detection of less than 2 micrograms/kg for both commodities. The HPLC/MS results for cheese extracts gave lower average recoveries of 55%. These results were also more variable. However, the apparent limit of detection for sterigmatocystin in cheese was still about 4 micrograms/kg.

Bread↗

Staling white pan bread: fundamental causes.

Staling, as it is applied to bakery foods, is a generic term covering a number of changes that occur in the products during normal storage. Consumers judge staleness by direct perception, which provides a subjective estimate that represents an unconscious integration of many factors. This review will discuss the main components of staling: (1) physicochemical changes of bread and related products (firming and texture deterioration of crumb and loss of crispness of crust) and (2) flavor changes. Section I will cover current theories of changes of firming and textural changes. The starch component of flour is generally considered to be responsible for these staling reactions. Consequently, the physicochemical involvement of amylose, amylopectin in these reactions will be fully discussed and current evidence supporting these theories (rheological, chemical, X-rays) will be given. Interactions of starch and surface active agents and other complexing compounds will be presented in Section II. In Section III, contribution of minor flour components and bakery food ingredients will be evaluated. Section IV will focus on organoleptic deterioration of products, presenting flavor changes that were observed during staling bread. Section V will discuss structural changes of breads caused by enzymolysis during bread production and storage as related to staling. Following the theoretical section (Sections I to V), Section VI will focus on practical control of staling. This discussion will cover the following factors: formulation, surfactants, enzymes, storage, freezing, and packaging.

Amylases↗

Bioavailability of starch in various wheat-based bread products: evaluation of metabolic responses in healthy subjects and rate and extent of in vitro starch digestion.

Glucose and insulin responses to bread products were evaluated in healthy subjects. Also studied were the rate of in vitro starch digestion and the content of in vitro resistant starch (RS). Three white-wheat-bread (WWB) products varying in crust-crumb ratio and monoglyceride addition, three bread products with a high soluble fiber content (HSFB), and two coarse-wheat breads (CB) were included. The metabolic responses to WWBs were in general higher than those to CB and HSFB products. The most prominent reduction in metabolic responses was noted with the CBs with intact kernels and the HSFBs with oat bran. The starch in these products was also more slowly released from a dialysis tubing after enzyme incubation of chewed samples. The RS content ranged from 0 to 1.7 g/100 g starch. HSFBs and the CB with intact kernels showed a higher satiety score than did the WWBs immediately after the test meal.

Adult↗

Folic acid enrichment of bread does not appear to affect zinc absorption in young women.

BACKGROUND: In several countries cereals are now enriched with folic acid to reduce the risk of neural tube defects. Human studies suggest that folic acid interferes with zinc absorption. This raises concerns about the zinc status of high-risk groups such as infants, pregnant women, and older persons. OBJECTIVE: We sought to determine the effect of added folic acid on zinc absorption from white bread with high and low zinc contents. DESIGN: Zinc absorption was measured in 15 healthy women (22-33 y), each of whom consumed 4 single meals spaced 2 wk apart in a randomized crossover design. The servings of bread (100 g) differed in zinc and folic acid contents as follows: A, 1.2 mg Zn and 17 microg folic acid; B, 1.2 mg Zn and 144 microg folic acid; C, 3.0 mg Zn and 17 microg folic acid; and D, 2.9 mg Zn and 144 microg folic acid. Meals were extrinsically labeled with 65Zn and absorption was estimated from whole-body retention measurements. Folate status was assessed by measuring plasma and erythrocyte folate and plasma homocysteine concentrations. RESULTS: Mean (+/-SD) zinc absorption did not differ significantly in relation to the folate content of the breads at either the low zinc content (38.8 +/- 13.5% and 40.6 +/- 16.5% for A and B, respectively; P = 0.74) or the high zinc content (26.7 +/- 9.3% and 22.7 +/- 6.6% for C and D, respectively; P = 0.16). There was no significant correlation between folate status and zinc absorption (r < 0.3, P > 0.1). CONCLUSION: Fortification of white bread with a commonly used amount of folic acid did not appear to influence zinc absorption at either a high or a low zinc content.

Adult↗

Phytic acid added to white-wheat bread inhibits fractional apparent magnesium absorption in humans.

BACKGROUND: Phytic acid has been reported to impair the absorption of minerals and trace elements such as calcium, zinc, and iron in humans. However, limited information is available on the effect of phytic acid on magnesium absorption. OBJECTIVE: The objective was to evaluate the effect of phytic acid on fractional apparent magnesium absorption in humans. DESIGN: Two stable-isotope studies were performed with 8-9 healthy adults per study. Test meals were based on 200 g phytic acid-free wheat bread; test meals with and without added phytic acid were served on days 1 and 3 according to a crossover design. Phytic acid was added in amounts similar to those naturally present in whole-meal (1.49 mmol) and in brown bread (0.75 mmol). Each test meal was labeled with 0.7 mmol (25)Mg or 1.1 mmol (26)Mg. The total magnesium content was standardized to 3.6 mmol in all test meals. Apparent magnesium absorption was based on fecal monitoring. RESULTS: The addition of phytic acid lowered fractional apparent magnesium absorption from 32.5 +/- 6.9% (no added phytic acid) to 13.0 +/- 6.9% (1.49 mmol added phytic acid; P < 0.0005) and from 32.2 +/- 12.0% (no added phytic acid) to 24.0 +/- 12.9% (0.75 mmol added phytic acid; P < 0.01). The inhibiting effect of phytic acid was dose dependent (P < 0.005). CONCLUSION: The results show that fractional magnesium absorption from white-wheat bread is significantly impaired by the addition of phytic acid, in a dose-dependent manner, at amounts similar to those naturally present in whole-meal and brown bread.

Adult↗

Amino acid fortification of bread fed at varying levels during gestation and lactation in rats.

The effects of protein quality improvement of white bread fed to female rats during pregnancy and lactation, under varying degrees of adequacy in food energy, on growth and brain development of the offspring have been studied. Weaning weight and the weight, protein and DNA of whole brain and major regions of the brain at weaning were determined. Lysine addition significantly increased all parameters, and threonine addition gave additional significant increments. Restricting energy intake decreased most parameters independent of protein quality. Brain cellularity was significantly higher in offspring of dams fed lysine and threonine fortified bread than in offspring of dams fed casein. All parameters measured in the offspring of dams fed lysine and threonine fortified bread at 70% ad libitum consumption were significantly increased over the values obtained in the offspring of dams fed unfortified bread ad libitum even though they had consumed 13% less protein and dietary energy during the pregnancy and lactation period. The implications of these findings for practical problems in human nutrition are considered.

Animals↗

Bread (white and whole wheat) and nonfat dry milk as sources of bioavailable calcium for rats.

These studies examined the bioavailability of calcium in bread (white and whole wheat) and nonfat dry milk. Most of the calcium in breads originated from nonwheat sources such as yeast food, milk replacer (a whey-soy blend) and calcium propionate. Bioavailabilities were calculated by the slope ratio technique. Slopes were determined using increases (over calcium-free diet) in femur calcium content of rats fed calcium-containing diets plotted against their actual calcium intakes as the test criterion. Compared to calcium in calcium sulfate (considered as 100%), the bioavailability of calcium in milk was 113.3%, and that in white and whole wheat bread 99.4% and 104.4% respectively. Thus, calcium in bread appears readily available, but still somewhat less than that in milk.

Animals↗

Starch and dietary fiber components are excreted and degraded to variable extents in ileostomy subjects consuming mixed diets with wheat- or oat-bran bread.

The study was conducted to determine if the excretion of starch and dietary fiber components varies in ileostomy subjects consuming diets high or low in dietary fiber. Excretion of starch, enzyme-resistant starch and dietary fiber components was studied in nine human subjects with ileostomies, who consumed (in a crossover design) a wheat bread-based diet (daily intake 274 g starch, 2.4 g enzyme-resistant starch and 14.4 g total dietary fiber) and a high fiber diet based on oat-bran bread (daily intake 243 g starch, 2.7 g enzyme-resistant starch and 40.2 g total dietary fiber). Food and excreta were collected on d 3 and 17. No significant differences in excretion of starch, enzyme-resistant starch or dietary fiber components were found on these 2 d in each dietary period. When subjects consumed the wheat bread-based diet they excreted (mean +/- SD) 3.3 +/- 1.7 g starch and 2.4 +/- 0.4 g enzyme-resistant starch daily, whereas when consuming the oat bran-based diet they excreted 4.5 +/- 3.1 g starch and 2.5 +/- 0.4 g enzyme-resistant starch. During both dietary periods subjects excreted significantly greater amounts of certain dietary fiber polysaccharide residues (fucose, galactose and uronic acid) than they ingested. This indicates a contribution of endogenous and/or microbial material to the dietary fiber value in ileostomy effluents. However, significantly less excretion of some dietary fiber polysaccharide residues, especially glucose residues, during the oat-bran bread-based dietary period was also noted. This was presumably caused by a degradation of mixed-linked (1,3),(1,4)-beta-D-glucans.

Adult↗

Older men and women efficiently absorb vitamin B-12 from milk and fortified bread.

Nothing is directly known about the bioavailability of vitamin B-12 from dairy products or fortified grain products. We directly studied vitamin B-12 absorption from water, milk and fortified bread in adult subjects using (58)Co-labeled vitamin B-12 and a whole body gamma-ray counter/spectrophotometer. Sixteen healthy men and women over the age of 60 y with normal serum levels of vitamin B-12 and normal basal gastric acid secretion were studied. (58)Co vitamin B-12 (0.25 microg) was administered in water, milk or fortified bread to each subject along with 185 kBq (5.0 microCi) (51)Cr as a stool marker. Whole body counting was performed 30 min after ingestion of the radioactive dose and at 7 and 14 d after dosing. Mean absorptions from water, milk and fortified bread were 55, 65 and 55%, respectively, and did not differ. The high body retention of the extrinsic vitamin B-12 label from milk and bread may warrant a greater use of such fortified products in the elderly to ensure vitamin B-12 adequacy.

Aged↗