Fresh Bread Research Articles

Effects of trehalose, transglutaminase, and gum on rheological, fermentation, and baking properties of frozen dough

Response surface methodology was used to study the effects of trehalose, transglutaminase, and locus bean gum on maximum dough height (Hm) and amount of CO2 production (CO2) with Rheofermentometer F3 of fresh and frozen doughs (18 wk at −18 °C), and specific volume and hardness of fresh and frozen dough breads. The high R2 of regression models (0.80–0.93%) were obtained for all four dependent variables for fresh and frozen doughs and breads. TR was significantly (P ⩽ 0.05) affecting Hm and CO2 of both doughs but in opposite ways, but it did only significantly affect specific volume of fresh dough bread. TG significantly (P ⩽ 0.05) improved specific volume and hardness for frozen dough bread, but was detrimental to those of fresh bread. LBG negatively affected CO2 of fresh dough and hardness of frozen dough bread. The study suggested TG was the most beneficial ingredient for the frozen dough bread.

Effects of Laccase and Xylanase on the Chemical and Rheological Properties of Oat and Wheat Doughs

The effects of Trametes hirsuta laccase and Pentopan Mono BG xylanase and their combination on oat, wheat, and mixed oat-wheat doughs and the corresponding breads were investigated. Laccase treatment decreased the content of water-extractable arabinoxylan (WEAX) in oat dough due to oxidative cross-linking of feruloylated arabinoxylans. Laccase treatment also increased the proportion of water-soluble polysaccharides (WSNSP) apparently due to the beta-glucanase side activity present in the laccase preparation. As a result of the laccase treatment, the firmness of fresh oat bread was increased. Xylanase treatment doubled the content of WEAX in oat dough and slightly increased the amount of WSNSP. Increased stiffness of the dough and firmness of the fresh bread were detected, probably because of the increased WEAX content, which decreased the amount of water available for beta-glucan. The combination of laccase and xylanase produced slight hydrolysis of beta-glucan by the beta-glucanase side activity of laccase and enhanced the availability of AX for xylanase with concomitant reduction of the amount and molar mass of WSNSP. Subsequently, the volume of oat bread was increased. Laccase treatment tightened wheat dough, probably due to cross-linking of WEAX to higher molecular weight. In oat-wheat dough, laccase slightly increased the proportion of WSNSP between medium to low molecular weight and increased the specific volume of the bread. Xylanase increased the contents of WEAX and WSNSP between medium to low molecular weight in oat-wheat dough, which increased the softness of the dough, as well as the specific volume and softness of the bread. The results thus indicate that a combination of laccase and xylanase was beneficial for the textures of both oat and oat-wheat breads.

Rankings: A Dramatization of the Incentives Created by Ranking Law Schools

Sellers in a competitive market shift resources from attributes buyers don't care about to attributes buyers do care about. In markets in which buyers rely on imperfect signals for quality, sellers move resources away from improving the quality of their product to enhancing the illusion of quality. For example, before freshness dating, when consumers tested the freshness of bread by squeezing it, bakers reportedly added chemicals to bread to preserve its softness longer, thereby creating the illusion of freshness. Similarly, law school rankings encourage schools to shift resources away from improving the quality of the education they provide in favor of investing in improving their standings in the rankings. Consequently, under the guise of serving the market, rankings which are based on the wrong criteria are likely to subvert the market because they both fail to measure accurately the quality of a school's education and reduce the quality of legal education. This piece dramatizes some of the ideas discussed in the preceding paragraph. It takes the form of a fifteen minute-play with three characters: a law school dean, a junior law professor, and a law student. The play illustrates how the incentives created by a ranking system could affect law schools and their administrators, faculty, and students. The play format is intended to make the ideas expressed more vivid.

Glutafin gluten-free fresh bread goes brown!

Glutafin gluten-free fresh bread goes brown!

Effects of Microcrystalline Cellulose and Hydroxypropylmethyl Cellulose on the Properties of Dough and Flat Bread (Iranian Barbari Bread)

There are many reports on the application of different hydrocolloids in the production of leavened breads; most of which show positive effects on bread quality. However, there is little information to prove such effect on flat breads. The main aim of this study was to improve the quality of Barbari dough and bread (Iranian flat bread) in terms of texture, taste and general acceptability of fresh bread. This was achieved by using two types of hydrocolloids; microcrystalline cellulose and hydroxypropylmethyl cellulose at 0.5% wheat flour basis. The results indicated that addition of either of the two cited hydrocolloids could improve dough and bread quality. However the latter had more positive effects on dough and bread properties mainly due to its more hydrophilic molecular property. Higher water absorption, improved dough stability time, softer bread texture and higher volume, as well as greater acceptability were all observed when hydroxypropylmethyl cellulose was added in bread recipe.

Pilot Study to Assess Isoflavone Intake in Middle-Aged Italian Subjects

Knowledge of isoflavone (IF) intake in Western populations is scarce, primarily because data about the content of these compounds in non-soy derived foods are incomplete or unavailable. The aims of this study were 1) to enrich the data available in literature about the IF content in traditional Italian foods, 2) to estimate daidzein (D) and genistein (G) intake in an Italian population sample. Eighteen Italian foods have been selected and analysed for IF content by GC-MS; the assessment of IF intake was performed in sixty healthy middle-aged Italian subjects after investigation of their dietary habits by food frequency questionnaire (FFQ). The mean IF intake was 171 ± 261 μg/die (26-1415 μg/die). The mean G intake was greater than D (98 ± 131 μg/die vs 76 ± 131 μg/die). As expected, soy products, even though poorly consumed (27%), resulted the main contributor to IF intake (IF intake was 473.4 ± 440 μg/die vs 75 ± 38 μg/die in soy consumers and non soy consumers respectively p<0.001). Among Mediterranean foods, the main contributor resulted fresh bread that is widely consumed (97%). The percentage contribution of the cereal group to mean IF intake was 91%; the legume, fruit and vegetables groups brought a low contribution (3%, 2% and 4% respectively). The total daily IF intake found was low and probably not sufficient to produce biological effects. However more studies are necessary to investigate whether low exposure to IF for a long time could have positive effects on human health.

Marriage: Royal and Edith

Marriage: Royal and Edith Royal's Story Like the small rabbits whose blood stained the swathes of hay I could not see the nests woven round hollow docks Below rusty seed heads, speckled eggs still nestled inside the rounded edge After the sliding blades cut. The horses stopped, Betty and Nell, chains quiet, Heads bent, lathered bodies welcoming a rest, as I carried a mother's treasure To the house as carefully as I cradled my daughter when her blood plashed my shoes, The crescent cut in her forehead matching the curve of the plowshare that almost killed her, but turned up treasure, too: Arrowheads, shaped white flint, sharp black, glinting in sunlight against spring furrows. I brought those treasures, too, for her, for you. She exclaimed. You Looked without remark, turned back to your distraction, never fully there. What else was there for me but work, or, failing that, the ring of stakes and shoes? Our lives hold empty air, words that circle feeling. My treasures were not yours. You shared none with me. Together in the same bed, we slept apart. So I, to pass the time, carried treasures stolen from another life. Arrowheads in white boxes on cotton beds stacked in the dining room cupboard drawer. Birds nests hooked above the freezer beside the snap-jawed traps and chains I now do not use. Worn horseshoes saved to, bell-like, clang against iron stakes. 50 Edith's Story They said Yd be an old maid, no boyfriend by twenty. When you bought my pie at the grange social, We sat together while you ate, talked, and smiled. I was too shy to make words. When you pulled into our driveway in your Model A. I could hardly believe my luck. The tongues, of course, said you married me because you must, but I was vindicated when the first Baby was four years coming. The first two years we played in father's second house. I dressed in your suit for Hallowe'en, we farmed, danced our Newlywed dance, until you and father argued, and sister Mary Claimed the farm, our house, our happiness. In your mother's house, I would not cut mold from week old bread. I baked fresh bread three times a week, watched as your body grew. With her, I cooked and cleaned, a servant still, careful of her orders, And told my daughters they could get used to anything. I had. I wanted time to read, to think, to write: to teach. I quoted bits of poems learned in school before I had to leave, needed To cook for mother, clean, feed stock. That poetry kept me sane, but How could you know my need? I watched out windows as you worked the fields, worried, but claiming my solitude, too. The accidental gifts you brought my day, Birds' nests, arrowheads, a flower from the woods, were poems of Your life, but I needed my own words, time to think. I was your partner, but your life was not all, so I claimed time stolen, And we grew apart. It was not all my fault, nor yours. No fault, truth be told. We stole, each from the other, to grow this chasm between our lives. —Patti Capel Swartz 51 ...

Physical properties of breads containing hydrocolloids stored at low temperature: II—Effect of freezing

Bread types such as dough samples (DB), semi-baked (SB) and full-baked (FB) breads were frozen stored for a week and further baked (DB or SB). Structure stabilizers such as xanthan (X), hydroxypropylmethylcellulose (HPMC), guar gum (GG) or locust bean gum (LB) were also added to the dough. Baking stage is important for bread quality after storage; additionally hydrocolloids provide stability in many frozen foods. Fresh bread samples were prepared for comparison. Yield in baked product, dough characteristics, specific volume, porosity, textural properties of both crumb/crust, moisture content of crumb/crust and finally crust thickness and colour were measured. Data grouping was performed using PCA analysis and correlations among the properties measured were found. X and LB addition resulted in the most stable dough, since strength and dough extensibility change during storage was low. Hydrocolloid stabilizers’ (HS) influence on final bread characteristics was more pronounced in DB and SB breads. Crust moisture content was higher in SB breads, and it reached values 11–19% higher in control and galactomannan-containing breads than in DB respective samples. Bread specific volume was highly correlated to the crumb moisture content, to the crumb/crust textural characteristics and to the yield in the baked product. It was not correlated to crust moisture content and thickness. Porosity and bread colour were not correlated to any of the other properties. Bread type and HS selection are important factors for improving stability during storage.

The dynamics of water in hydrated white bread investigated using quasielastic neutronscattering

The dynamics of water in fresh and in rehydrated white bread is studied using quasielasticneutron scattering (QENS). A diffusion constant for water in fresh bread, withouttemperature gradients and with the use of a non-destructive technique, is presented herefor the first time. The self-diffusion constant for fresh bread is estimated to beDs = 3.8 × 10−10 m2 s−1 and the result agrees well with previous findings for similar systems. It is also suggestedthat water exhibits a faster dynamics than previously reported in the literature usingequilibration of a hydration-level gradient monitored by vibrational spectroscopy. Thetemperature dependence of the dynamics of low hydration bread is also investigated forT = 280–350 K. The average relaxation time at constant momentum transfer(Q) shows an Arrhenius behavior in the temperature range investigated.

Comparison of chemical, physical, micro-structural, and microbial properties of breads supplemented with sweetpotato flour and high-gluten dough enhancers

Abstract The objective of this study was to compare the chemical, physical, micro-structural, and microbial properties of breads supplemented with sweetpotato flour and high-gluten dough enhancers. Six breads, with and without dough enhancers (DE) and varying percentages of sweetpotato flour (SPF) were processed. Breads were stored at 22±2 °C, and samples were measured on Days 0, 2, 4, 6, and 8. Moisture, ash, fat, a w , color, loaf volume, specific volume, density, texture, and weight loss were analyzed on Day 0, and β -carotene on the Days 0 and 8. The micro-structural and microbial properties of the sweetpotato breads were also compared. The fresh breads (Day 0) had moisture contents ranging from 36.66 to 41.56. β -Carotene was highest in breads containing 65% SPF. All breads were significantly ( P

Characterization of water distribution in bread during storage using magnetic resonance imaging

A soy bread of fully acceptable quality and containing 49% soy ingredients (with or without 5% almond powder) has been recently developed in our laboratory. An investigation on water distribution and mobility, as probed by proton signal intensity and T2 magnetic resonance images, during storage was designed to examine possible relations between water states and hindered staling rate upon soy or soy-almond addition. Water proton distribution throughout soy-containing loaves was found to be very homogeneous in fresh breads with and without almond, with minimal water migration occurring during prolonged storage. In contrast, traditional wheat bread displayed an inhomogeneous water proton population that tended to change (with higher moisture migration towards the outer perimeter of the slice) during storage. Similar results were found for water mobility throughout the loaves, as depicted in T2 images. On intensity images of all considered bread varieties, the outer perimeter corresponding to the crust exhibited lower signal intensity due to decreased water content. Higher T2 values were found in the crust of soy breads with and without almond, which were attributed to lipids. The results indicated that the addition of soy to bread improved the homogeneous distribution of water molecules, which may hinder the staling rate of soy-containing breads. However, incorporation of almond had little effect on the water proton distribution or mobility of soy breads.

Effect of Trehalose on Fresh Bread and Bread Staling

Effect of Trehalose on Fresh Bread and Bread Staling

Effects of Linalyl Oleate on Soybean Oil Flavor and Quality in a Frying Application

AbstractBread pieces were fried at 180 °C in soybean oil (SBO) containing no additives (control), 0.1% linalyl oleate (LO), or 10 ppm methyl silicone (MS). After 2 h of heating, the MS‐containing oil was the most stable, followed by the oil with LO and the control, based on conjugated dienoic acid percentage (CD) and the ratio of linoleate%/palmitate%. Oil extracted from the fresh fried bread showed similar, but not significant, trends for CD and PV. Fresh and stored (60 °C, 2 days) bread fried in LO‐containing oil had less hexanal than the other two treatments, and the stored LO bread had less t,c‐ and t,t‐2,4‐heptadienal than the control. Fresh bread fried in LO‐containing oil had a less rancid flavor than did the other two treatments, and the LO treatment had less fishy flavor than the control. In stored bread, the MS treatment was less rancid than the control. In oil extracted from the stored bread, the amounts of t,c‐2,4‐heptadienal and 2‐decenal correlated (p ≤ 0.05) with the amounts of individual unsaturated fatty acids and with CD, but only t,c‐2,4‐heptadienal correlated with the PV. The t,c‐2,4‐heptadienal correlated with individual Polyunsaturated fatty acids (PUFA) in freshly fried bread. In general, oil and fried bread had improved flavor quality and/or oil stability when they contained MS or LO.

Crystallinity changes in wheat starch during the bread-making process: Starch crystallinity in the bread crust

The crystallinity of starch in crispy bread crust was quantified using several different techniques. Confocal scanning laser microscopy (CSLM) demonstrated the presence of granular starch in the crust and remnants of granules when moving towards the crumb. Differential scanning calorimetry (DSC) showed an endothermic transition at 70 °C associated with the melting of crystalline amylopectin. The relative starch crystallinity, as determined by X-ray and DSC, from different types of breads was found to lie between 36% and 41% (X-ray) and between 32% and 43% (DSC) for fresh bread crust. Storage of breads in a closed box (22 °C) for up to 20 days showed an increase in crust crystallinity due to amylopectin retrogradation both by X-ray and DSC. However, DSC thermograms of 1-day old bread crust showed no amylopectin retrogradation and after 2 days storage, amylopectin retrogradation in the crust was hardly detectable. 13C CP MAS NMR was used to characterize the physical state of starch in flour and bread crumb and crust. The intensity of the peaks showed a dependence on the degree of starch gelatinization. Comparison of the results for two different types of bread showed that the baking process influenced the extent of starch crystallinity in the bread crust. Amylopectin retrogradation, which is the main process responsible for the staling of bread crumb, cannot be responsible for crispness deterioration of the crust as amylopectin retrogradation upon storage of breads could only be measured in the crust after 2 days storage. Under the same conditions loss of bread crust crispness proceeds over shorter times.

Hyped‐up for Hox in Hyderabad

The EMBO Workshop on Upstream and Downstream of Hox Genes took place in Hyderabad, India, between 14 and 17 December 2005, and was organized by R. Mishra and F. Karch. ![][1] For many years, EMBO workshops dealing with new insights into the regulation and function of Hox genes have been held in Switzerland. However, last year, the EMBO World Programme, together with the Centre for Cellular and Molecular Biology (CCMB), held a workshop entitled Upstream and Downstream of Hox Genes in the CCMB's hometown of Hyderabad, India. Imagine beautiful gardens full of butterflies and palm trees, a delightful guest house neighbouring a state‐of‐the‐art research centre, all in a peaceful oasis surrounded by a pulsating and crowded Indian city. The question at the beginning of the meeting was whether the talks and discussions would match the stunning environment; it was answered rapidly and affirmatively. Hox genes have had an illustrious and curious history. Perhaps one of the most famous images in biology from the past century is the four‐winged mutant of the fruit fly Drosophila melanogaster caused by mutations in the Hox gene Ultrabithorax ( Ubx ). This fascinating mutant fly, discovered and characterized by Edward B. Lewis, has motivated many investigators to join the field to understand how these genes are responsible for such complex changes in morphology. Another highlight of Hox history was Matthew Scott's, William McGinnis's and Walter Gehring's discovery of the homeodomain—a 60‐amino‐acid DNA‐binding motif now known to be a key domain in hundreds of genes throughout the animal, fungal and plant kingdoms. Although a lot has been learned through experiments stemming from these important discoveries, there are still many open questions. Among the questions being debated in the field and at the meeting are: How is the regulation of the Hox genes initiated and maintained? How do Hox proteins … [1]: /embed/graphic-1.gif

Morning Ritual, and: Knowing, and: Body Reading

Morning Ritual Every morning, after the roosters Crow back whatever prayers were passed Down to them that dawn From the keeper of their order up in heaven, I drink my coffee To the sound of squealing pigs Being bled to death In the market up the road – the same market Where I buy my fresh bread For my peanut butter and jam. The pigs are bled through an axillary wound. You can see it coming throughout the day before, Hogs tied sideways to the backs of bicycles, Tight as a spine, going as far as the border Where the price is right. You will pass them On the asphalt to the city I get My peanut butter and jam from. They know The bikeways out of nowhere And suddenly they're alongside your jeep. I lie: only goats are taken to the border. The goats are bled differently, And skinning is harmless after slaughter: All you do is a vertical skin-slit Between the shinbone and Achilles' tendon, [End Page 30] Stick a thin metal rod Through it, up the thigh, pull it out Then blow, mouth to wound, Until your breath dehisces Fascia and dermis, reaching the belly: Your hands Should even out the trapped air. Between blowing and tapping The animal is tight as a drum. Now the knife that slits the throat. Who knows What you'll need skin for. Knowing Tell me where you'd like to be buried When you die And I'll tell you your flag's colors And what I never Told my father when I saw A pregnant pomegranate tree For the first time In the evening square Alone with other trees I never knew To ask their name In a Mediterranean island town Whose name I forget now And whose history stains As only pomegranate seeds can [End Page 31] When he loosens them by hand In a bowl with coconut Sprinkled on top You and I in love The drunk bar owner clapping For a thousand bat wings That burst into song Out of trees I never knew And the more he clapped he laughed And the singing grew And our standing in the middle Of departure grew You knowing where You'd want to be buried When you die Body Reading The scent is a molecular Memory, a hexagon, And the body is drowned Head down in phenolated cloth. Between truce and abeyance This is neither. I thought my cadaver was a man But when the back was done with blade . . . I'll come out and say it: The heart is a cavity with thin walls And within the skull hides a butterfly bone. Sometimes truth isn't everything. Sometimes the memory grows [End Page 32] Like silver hair and an accessory spleen. Like a left-handed bullet And the colonel on table nineteen Who signed his donor card Then shot himself through the temple, Parallel to the eyes. This is the body and everything in it. This is Marcia's Bach on cello And Jennifer's Moonlight Sonata, And readings about light upon light And an incandescent olive tree That wasn't really on fire. This is a story I love. I love its furious form And I love its hours. It has hours held back in the body Word for word like a prophet Of a scream. It has a man in a bed, His wife in a chair In a corner of the room sewing Nothing, it has a man in a bed Singing. And the song Has a sea and a sailboat, The daylight coming And going, his wife in a chair In a corner of the room listening For things that incubate To fingershut the eyes of the dead.

Analysis of Volatile Bread Aroma for Evaluation of Bread Freshness Using an Electronic Nose (E-Nose)

ABSTRACT This paper presents the use of a tin-oxide sensor array and self-organized map (SOM)-based E-nose for analysis of volatile bread aroma and explores its ability to cluster bread odor data according to the freshness of bread. A low cost tin-oxide sensor array based electronic nose system has been used for the classification of state of freshness of bread. The sensor data was acquired for a period of 3 weeks, and an unsupervised self-organizing map (SOM) model was trained using this data to correlate the sensor response to classify the bread as fresh and stale. A comparative evaluation of 3 week' of bread data was carried out using the SOM. The results suggest that the system developed is able to predict the state of bread as fresh and stale up to 98% accuracy if the test bread data sets are of the same week. The classification accuracy reduces to 75–85% if test bread data sets are from different weeks. The model is also applied on three different brands of bread and similar classification results are obtained.

Trading Roles: Gender, Ethnicity, and the Urban Economy in Colonial Potosí

Trading Roles: Gender, Ethnicity, and the Urban Economy in Colonial Potosí

Starch Retrogradation and Firming of Bread Containing Hydroxypropylated, Acetylated, and Phosphorylated Cross‐Linked Tapioca Starches for Wheat Flour

ABSTRACTThe present investigation aims at understanding the role of chemically modified starch on the firmness of fresh or stale bread. Bread was prepared from wheat flour or substituted wheat flour that contained 18% chemically modified tapioca starch and 2% vital gluten. Hydroxypropylated tapioca starch (HTS), acetylated tapioca starch (ATS), phosphorylated cross‐linked tapioca starch (PTS), and native tapioca starch (NTS) were tested. Bread prepared from the substituted flour with PTS showed a firmer texture on the day of baking compared with bread prepared from NTS, HTS, and ATS. PTS retained its granular structure in the gluten network after baking and seemed to play the role of filler particles in the gluten matrix, thereby increasing firmness of fresh bread crumb. Bread prepared from the substituted flour with HTS or ATS firmed at a lower rate and showed a lower endothermic melting enthalpy of amylopectin after three days of storage compared with NTS or PTS. These findings suggest that the staling of bread containing chemically modified tapioca starch involves recrystallization of amylopectin.

Glucose oxidase effect on dough rheology and bread quality: A study from macroscopic to molecular level

Enzymes are used in baking to improve dough handling properties and the quality of baked products. Glucose oxidase (GO) is an enzyme with oxidizing effect due to the hydrogen peroxide released from its catalytic reaction. In this study, the macroscopic effect of increasing glucose oxidase concentrations on wheat dough rheology, fresh bread characteristics and its shelf life during storage was determined. A reinforcement or strengthening of wheat dough and an improvement of bread quality can be obtained with the addition of GO, although inverse effects were obtained when excessive enzyme levels were added. The analysis of the gluten proteins at molecular level by high performance capillary electrophoresis and at supramolecular level by cryo-scanning electron microscopy revealed that the GO treatment modified gluten proteins (gliadins and glutenins) through the formation of disulfide and non-disulfide crosslinks. The high molecular weight glutenin subunits showed to be the most susceptible glutenin fraction to the oxidation action of GO. Excessive addition of GO produced an excessive crosslinking in the gluten network, responsible of the negative effect on the breadmaking properties.