Waxy durum acts as a unique form of crumb softener in bread

Flour milled from waxy durum grain was incorporated into bread formulations and its effects on crumb softness and loaf volume compared to those of added fats and emulsifiers. Waxy durum had a small effect on increasing loaf volume, and little of this effect could be explained by dough height or oven spring; effects of most other additives were closely related to dough height or oven spring. For all additives, the relationship between crumb softness and loaf volume fitted a power law relationship. Waxy durum and some of the additives had a greater softening effect than predicted from their effect on volume while others produced a much firmer crumb. With only one exception, when combined with other additives waxy durum reduced compression of the crumb more than predicted on the basis of the effects on loaf volume of the additives alone. In common with some of the added lipids, during compression analysis, crumb prepared with waxy durum flour had similar levels of structural damage as crumb baked from the standard formulation; other lipids and emulsifiers produced more fragile crumb. Waxy durum flour appears to have unique effects on crumb softness.     

Waxy durum and fat differ in their actions as improvers of bread quality

Fat is commonly added to bakery products to improve eating qualities and extend shelf life. Flour milled from waxy durum grain was incorporated into bread formulations and its effects on crumb softness and loaf volume compared to those of added fat. Low levels of fat (0.1-0.3% of flour weight) softened the bread crumb and increased loaf volume. Most of the softening effects were evident in the crown of the loaves protruding above the tin and a high proportion of the reduction in compression was associated with increased volume. Loaves baked with waxy durum flour were softer than those baked with fat and the softening effects were evident both in the crown of the loaf and at its base where it had been confined within the tin. Waxy durum flour reduces compression independently of increased volume. It is suggested waxy durum flour acts by slowing the migration of water from the gluten phase to the starch phase so maintaining the level of mobile water in the gluten where it acts as a plasticiser. Independent organoleptic assessment of bread quality baked with combinations of waxy durum and fat confirmed the quality enhancing effects of waxy durum flour.     

Storage stability,micronisation, and application of nutrient-dense fraction of proso millet bran in gluten-free bread

This study aimed to valorise the underutilised by-product of proso millet decortication. Millet bran was sieved into three fractions with substantially different nutritional profile. The fraction with diameter <500 μm had the highest nutrient density (14% protein, 26% starch, 36% dietary fibre, 9% fat, and 3 mg GAE/g phenolics (d.w.)) and was analysed for oxidative stability, micronisation effect under cryogenic or ambient conditions (2, 4, 8, 12 min), and baking applicability. The bran was oxidatively stable under refrigerator conditions for 150 days. Micronisation slightly increased the antioxidant activity measured by FRAP and ABTS assays as well as the content of fibre soluble in water and 78% ethanol as the bran particle size decreased from 171 μm to 26–46 μm. Gluten-free bread containing 10% of the nutrient-dense fraction of millet bran had higher dietary fibre (76%) and phenolics content (117%), improved volume and crumb softness, regardless of the bran particle size (diameter of 50th percentile 171 vs. 26 μm).     

Quality characteristics of northern-style Chinese steamed bread prepared from soft red winter wheat flours with waxy wheat flour substitution

Quality characteristics of northern-style Chinese steamed bread (CSB) prepared from two soft red winter (SRW) wheat flours blended with 0–30% waxy wheat flour (WWF) were analyzed to estimate the influence of starch amylose content. The increased proportion of WWF in blends raised mixograph absorption with insignificant changes in protein content and dough strength-related parameters. WWF incorporation generally increased specific volume and crumb softness of CSB. The analysis of covariance revealed that CSB quality attributes were little affected by protein content and dough strength-related parameters, indicating that starch amylose content was largely responsible for the changes in CSB quality. Flour blends with 5–10% WWF, of which starch amylose content was 22.4–24.7%, produced CSB with superior crumb structure compared to other blends, but insignificant changes in surface smoothness, stress relaxation and total score compared to the respective control wheat flours. Flour blends with 15% WWF to produce a starch amylose content of 21.4–22.7% exhibited reduced staling of CSB with total scores comparable to the respective control wheat flours. CSB prepared from blends with more than 10% WWF exhibited a higher soluble starch content, indicative of reduced starch retrogradation, than that prepared from wheat flours without WWF during storage for 3 days.     

Effect of Detarium microcarpum (Dm) and Mucuna flagellipes (Mf) gums on the quality of white bread

Incorporation of Detarium Microcarpum (Dm) and Mucuna flagellipes (Mf) water soluble polysaccharides (gums) at 0.0 to 0.5% levels in wheat flour was studied to evaluate their effect on the rheological properties of wheat flour dough and white bread quality. At all levels of incorporation, there were increases (p 0.05) in water absorption of the dough. Doughs containing gums had higher (p 0.05) mixing tolerance index than the control. Set back viscosities decreased by 4.0 RVU and 9.0 RVU with increased levels of Dm and Mf gum incorporation, respectively. Significantly (p 0.05) higher oven spring occurred in all the gum substituted white bread when compared to the control. The 0.5% gum substituted breads had a significantly (p 0.05) higher sensory score for crumb grain, texture but lower (p<0.05) crumb firmness than the control as determined instrumentally. Textural analysis after 5 days storage revealed that Dm and Mf gums improved moisture retention properties of the bread and reduced crumb firming tendency.     

Physico-chemical properties of low-fat cookies containing wheat and oat bran gels as fat replacers

Wheat and oat bran-based fat replacers in the form of gels were used for partial replacement of fat (30–50%) in a cookie formulation. Dough rheological properties, physical (cookie dimension, weight loss, moisture content and water activity), textural (hardness and fracturability), colour and sensory parameters were evaluated to characterize full-fat and fat-reduced cookies. Based on the obtained results it was concluded that the fat reduction in cookie formulation at the level of 30% maintained sensory properties of the full-fat cookies. Therefore, this level of fat replacement was chosen for further analysis: 30% WBG (wheat bran gel-containing cookies) and 30% OBG (oat bran gel-containing cookies) were examined in terms of nutritional and functional properties. It was revealed that fat replacement using bran gels at the level of 30% resulted in the fat-reduced added-value cookies in terms of dietary fibre, minerals and phenolics. 30% WBG cookies possessed higher dietary fibre, mineral and phenolic content in comparison to 30% OBG and the full-fat cookies.     

Mechanical Properties of Bread Crumb Prepared from Flours of Different Dough Strength

Bread quality depends in part on the textural properties of the crumb; softness and strength being two important textural attributes. This study examined differences between instrumentally-measured textural properties of the crumb of bread made from two flours; one possessing extra strong dough mixing characteristics and a second of moderate strength (red spring wheat). Bread crumb specimens, notched and un-notched, were subjected to tensile loading and the crumb's initial (elastic) modulus, stress at failure (crumb strength) and tear resistance were determined. The same mechanical parameters were determined on bread crumb that had been compressed approximately five-fold in order to destroy crumb structure. For un-notched specimens, stiffness and strength were of the order of 11 and 1 kN/m², respectively, whereas after compression they were 230 and 10 kN/m², respectively. For CWRS breadcrumb, toughness increased from 4·1 J/m²to 12·3 J/m²following crumb compression. Bread crumb made from a flour possessing extra strong dough properties was stronger than bread crumb made from a more conventional red spring wheat flour, and there was an indication that extra strong flour bread crumb specimens were stiffer. Compression of the bread crumb lessened the difference between the mechanical properties of the two bread types, particularly for strength and tear resistance. The results indicated that bread crumb structure plays a predominant role in the textural properties of bread crumb.     

Multivariable Analysis of Gluten-Free Pasta Elaborated with Non-Conventional Flours Based on the Phenolic Profile,Antioxidant Capacity and Color

The phenolic compounds, color and antioxidant capacity of gluten-free pasta prepared with non-conventional flours such as chickpea (CHF), unripe plantain (UPF), white maize (WMF) and blue maize (BMF) were analyzed. Fifteen phenolic compounds (five anthocyanins, five hydroxybenzoic acids, three hydroxycinnamic acids, one hydroxyphenylacetic acid and one flavonol) were identified in pasta prepared with blue maize, and 10 compounds were identified for samples prepared with white maize. The principal component analysis (PCA) led to results describing 98% of the total variance establishing a clear separation for each pasta. Both the proportion (25, 50 and 75%) and type of maize flour (white and blue) affected the color parameters (L*, C _ab *, h _ab and ΔE* _ab ) and antioxidant properties (DPPH, ABTS and FRAP methods) of samples, thus producing gluten-free products with potential health benefits intended for general consumers (including the population with celiac disease).     

Expansion capacity of doughs: methodology and applications

An instrument for measuring the expansion capacity of dough was developed based on the application of a known negative pressure and measurement of the height reached by the dough using a dough height tracker. At a negative pressure of 74 cm of Hg, the same maximum heights were reached after expansion at all stages of processing from after mixing to end of proof. For this negative pressure (74 cm Hg), the expanded dough heights measured immediately after mixing for doughs from 9 hard and 10 soft wheat flours coincided closely with the heights reached by corresponding baked loaves (r=0.99). Pizza doughs were also found to give a good correlation with baked pizza height (r=0.78, significant at 1% level). The method was used to obtain information about the timing of the effects of bromate addition and flour lipid extraction during processing. An increase in dough expansion capacity from bromate addition was observed only after the final proofing stage. Gas cell fineness of the bread crumb, measured by CrumbScan software, was decreased by bromate addition but gas cell elongation was increased. Effects of lipid removal were different. An increase in expansion capacity occurred at all processing stages and gas cell fineness of the bread crumb was increased. Expansion capacity appears to be an inherent property of a dough and may have potential as a rapid measurement to predict baking performance.     

Wheat products as acceptable substitutes for rice

The objective of the study was to compare the acceptability to semi-trained US American and Asian palatability panelist, of four wheat products processed to be possible replacers of rice in human diets. Products evaluated using rice as the control standard of excellence were steamed whole wheat, couscous (steamed, extracted wheat flour semolina), rosamarina (rice shaped, extracted wheat flour pasta), and bulgur (steamed, pre-cooked partly debranned, cracked wheat). Using a ten point hedonic rating scale, both groups of panelists gave rosamarina closely followed by couscous, most favorable ratings although these ratings were somewhat lower than that of the positive control, steamed polished rice. Bulgur wheat was given the lowest evaluation and was, in general, found to be an unacceptable replacement for rice by both American and Asian judges because of its dark, greasy color and distinctive flavor. In their personal dietaries, judges included rice from 0.25 to 18 times per week with the Asian judges consuming rice significantly more times per week than did the American judges (10.8±4.71 vs 1.75±1.65,p<0.01). However, rice consumption patterns, nationality, race, or sex of the judges was not demonstrated to affect scoring of the wheat products as rice replacers.Published as University of Nebraska Agricultural Research Division Journal Series No. 9826. Supported by University of Nebraska Agricultural Research Division Project 91-031.     

Oat malt as a baking ingredient – A comparative study of the impact of oat,barley and wheat malts on bread and dough properties

Oat malt is a nutritionally rich ingredient mainly used in a small number of speciality products. The aim of this study was to evaluate the suitability of oat malt in wheat baking. The effect of oat malt on bread and dough properties at levels ranging from 0.5% to 5% was studied and compared with barley and wheat malts. The addition of all malts increased loaf specific volumes. Barley and wheat malts at levels above 2.5% led to a sticky and coarse crumb, but the effect of oat malt on the crumb grain was negligible. Rheological characterisation could not explain the superior baking performance of oat malt, as it increased extensibility and decreased resistance extensively indicating weakening of the extensional properties of the gluten network. The high lipolytic activity may have compensated for the loss of dough strength by improving the surface properties of gas cells. The results show that oat malt can be used in wheat baking to improve the loaf volume and nutritional quality without the detrimental effects associated with the excess amylolytic activity of barley and wheat malts.     

The Role of Dextrins in the Stickiness of Bread Crumb made from Pre-Harvest Sprouted Wheat or Flour Containing ExogenousAlpha-Amylase

Dextrins were extracted in water from bread made from pre-harvest sprouted wheat or standard flour supplemented with exogenousalpha-amylases. The dextrins were separated by gel permeation chromatography and the dextrin content (% of crumb weight) determined for different degree of polymerisation (DP) size classes; DP 1–2, DP 3–10, DP 11–50, DP 51–200 and DP >200. There were significant correlations between the dextrin content in each size class and crumb stickiness (r=0·84–0·91, 22 df ). The most significant correlation (r=0·96) was between total dextrin content and crumb stickiness. Addition of dextrins of various DP ranges from various sources to standard flour produced bread with sticky crumb. Again, the degree of stickiness was generally related to the amount of total dextrin in the crumb and not to size distribution of dextrins. In this instance, extensive enzymic hydrolysis of starch was not necessary to produce sticky crumb; the dextrins caused crumb stickiness directly. Addition of dextrins to reconstituted gluten–starch flour produced bread with unexpectedly low dextrin levels and correspondingly low stickiness scores. It is concluded that, to produce sticky crumb, high levels of dextrin of any size are necessary in the crumb; a sticky mass is produced when dextrins dissolve in the excess «free» water that is normally «bound» to starch, gluten and other insoluble components of bread crumb.     

Effect of temperature on the starch content of potato callus tissue

Starch content was determined in Lemhi Russet callus grown on MS medium for 2 and 4 weeks at 25, 15, and 5°C with 50 μM 2,4-D or 10 μM picloram as the only plant growth regulator. A treatment of 5°C for 4 weeks followed by 25°C for 2 and 4 weeks was included to simulate reconditioning. Callus starch content ranged from 0.01 to 0.08% on a wet weight basis and 0.5 to 4.0% on a dry weight basis. Starch content was highest after 2 weeks at 25 and 15°C and decreased with time in a similar manner at both 25 and 15°C. Starch content decreased at 5°C, then increased significantly during simulated reconditioning at 25°C. Starch content was higher in callus grown with 50 μM 2,4-D than in callus grown with 10 μM picloram. After staining the callus with I₂-KI solution, starch granule formation was observed in the callus grown with 50 μM 2,4-D, while little granule formation was observed in the callus grown with 10 μM picloram.     

Effect of barley flour addition on the physico-chemical properties of dough and structure of bread

The effects of different percentages of barley flour (i.e. 0–25%) in wheat flours on the physico-chemical properties and structure of dough and bread were investigated. As the percentage of barley flour in mixed flour was increased, its protein and gluten contents decreased whereas the ash content and enzyme activity increased. The rheological characteristics of the four dough mixes were studied using Farinograph, Extensograph and Alveograph. The water absorption (p < 0.01) and stability (p < 0.05) decreased significantly as the percentage of barley flour increased, while no changes were observed in the extensibility and maximum heights. Significant differences were observed in the structural and physical properties as well as in the image analysis of breads. With the increase in the percentage of barley flour, the crumb apparent density decreased (p < 0.1) whereas the porosity (i.e., fraction to total volume) increased (p < 0.1). Overall, the shape and pore structure at 10% barley flour (W90B10) were similar to the pure wheat flour bread, while addition at 15 and 25% of barley flour (W85B15 and W75B25) showed more non-uniform and larger pores.     

Oat malt as a baking ingredient – A comparative study of the impact of oat,barley and wheat malts on bread and dough properties

Oat malt is a nutritionally rich ingredient mainly used in a small number of speciality products. The aim of this study was to evaluate the suitability of oat malt in wheat baking. The effect of oat malt on bread and dough properties at levels ranging from 0.5% to 5% was studied and compared with barley and wheat malts. The addition of all malts increased loaf specific volumes. Barley and wheat malts at levels above 2.5% led to a sticky and coarse crumb, but the effect of oat malt on the crumb grain was negligible. Rheological characterisation could not explain the superior baking performance of oat malt, as it increased extensibility and decreased resistance extensively indicating weakening of the extensional properties of the gluten network. The high lipolytic activity may have compensated for the loss of dough strength by improving the surface properties of gas cells. The results show that oat malt can be used in wheat baking to improve the loaf volume and nutritional quality without the detrimental effects associated with the excess amylolytic activity of barley and wheat malts.     

Formulation and sensory evaluation of Prosopis alba (Algarrobo) pulp cookies with increased iron and calcium dialyzabilities

Prosopis alba (algarrobo) is an important indigenous specie, which fruits are used as food and feed since ancient times. Cookies containing algarrobo pulp (AP) with increased iron and calcium availabilities were formulated and sensory evaluated. AP is preferred as food ingredient because of its high sugar content and pleasant flavour. Formulated cookies mean proximal composition was 8.9 g/100 g protein, 7.2 g/100 g dietary fiber, 25 g/100 g total sugar, and 18.5 g/100 g crude fat with iron and calcium contents 30 ppm and 340 ppm, respectively. Ascorbic (AA) and citric (CA) acids at different mM acid: mM Fe were added in order to increase mineral availabilities being evaluated by an in vitro method. Those ratios were 5:1 and 10:1 for AA:Fe whereas for CA:Fe were 50:1 and 100:1 and combinations of them. After chosen the best AA:Fe and CA:Fe ratios (5:1 and 50:1, respectively), sensory evaluation with trained sensory panel and a consumer acceptability test with one hundred and seventy untrained judges were carried out. Acceptability test showed that 77.65% of the people (< 25 years old 41.76%, 25-50 years old 20.00% and > 50 years old 15.89%) tasting final formulated cookies indicated that they "like very much" or "moderately like" and there were not consumers rejecting them.     

In Vitro Digestibility of Banana Starch Cookies

Banana starch was isolated and used for preparation of two types of cookies. Chemical composition and digestibility tests were carried out on banana starch and the food products, and these results were compared with corn starch. Ash, protein, and fat levels in banana starch were higher than in corn starch. The high ash amount in banana starch could be due to the potassium content present in this fruit. Proximal analysis was similar between products prepared with banana starch and those based on corn starch. The available starch content of the banana starch preparation was 60% (dmb). The cookies had lower available starch than the starches while banana starch had lower susceptibility to the in vitro -amylolysis reaction. Banana starch and its products had higher resistant starch levels than those made with corn starch.     

Dose response to soluble fiber in barley in lowering blood lipids in hamster

Diets containing 0, 25, 50, or 75% finely ground barley (high in soluble fiber and soluble -glucans) were fed to groups of hamsters. After four weeks, serum total cholesterol (CH) levels in these animals were most elevated in the group fed the barley-free (0% barley) diet. Compared to animals eating this diet, the 25% barley diet lowered CH by 16.4%. However, the 50% barley diet lowered CH further by only 4.1% while the 75% barley diet caused virtually no further lowering of CH. Thus, the CH-lowering response to barley cannot be viewed as a dose dependent response. The lowering pattern for serum triglycerides, however, suggested a dose dependent response. Serum total-CH: high-density-lipoprotein (HDL)-CH or low-density-lipoprotein (LDL)-CH:HDL-CH ratios were not significantly affected by barley level in the diets.     

Effects of processing on protein nutritive quality of coconut Cocos nucifera products

Pared, comminuted and blanched coconut meat was freeze-dried at25 ^°C for 24 hours and pulverized. Whole coconut meal wassolvent extracted with n-hexane to yield a defatted meal while full-fatcoconut protein concentrate (FFC-PC) containing 27.60% protein wasprepared by alkali extraction of undefatted meal followed by isoelectricprecipitation. Defatted coconut meal had a significantly (p 0.05)lower crude fat but higher protein content than whole coconut meal.Similarly, FFC-PC had a significantly (p 0.05) higher proteinbut lower carbohydrate content than whole coconut meal and defattedcoconut meal. Whole coconut meal, defatted coconut meal and FFC-PChad PERs of 1.98, 2.18 and 2.48 respectively, with NPRs of 2.86, 3.28and 3.92, respectively. Protein digestibility values of 88.75%, 89.30%and 94.02% were obtained for whole coconut meal, defatted coconutmeal and full-fat coconut protein concentrate, respectively. Growthresponse of animals showed that FPC-PC was superior to all other testdiets.