R. A. Miller

Factors in hard wheat flour responsible for reduced cookie spread

ABSTRACT Time-lapse photography showed that, during baking, the diameter of sugar-snap cookies increased linearly then suddenly became fixed. Therefore, cookie diameter was a function of spread rate and set time. Cookies made with soft wheat flour were significantly larger in diameter (184 mm) than those made with hard wheat flour (161 mm). Cookies made with soft wheat flour set later (5.8 min) during baking than those made with hard wheat flour (5.1 min). The differences in set time within cookies made with various hard wheat flours or within cookies made with various soft wheat flours appeared to be affected by flour protein content. However, other factors also affected the difference in set time between cookies made with hard wheat and soft wheat flours. Cookies made with soft wheat flour spread at a faster rate (7.8 mm/min) than those made with hard wheat flour (4.6 mm/min). The level of soluble starch in the flour appeared to cause the difference in spread rate between cookies made with hard wheat an...

Role of Salt in Baking

The general term salt in baking formulas refers to sodium chloride. Salt is one of the four essential ingredients in bread (flour, salt, yeast, and water). The functions of salt in baking include stabilizing yeast fermentation rate, strengthening the dough, enhancing the flavor of the final product, and increasing dough mixing time. The flavor-enhancing function of salt is well known. Omitting salt from the formula results in baked products that are quite tasteless. At the level used, salt does not impart a salty taste to the product but rather brings out the other flavors in the system. It is also known to increase sweetness and mask metallic, bitter, or other off flavors. The reasons and mechanism of this function of salt are outside the expertise of the authors and will not be discussed further in this manuscript. An important function of salt in breadmaking is its stabilizing effect on fermentation. In dough made without salt, the yeast ferments excessively resulting in gassy, sour dough and baked products with open grain and poor texture (14). Salt inhibits or “controls” fermentation rate by decreasing the rate of gas production (6), which results in longer proof times (18,25). This appears to be the result of increased osmotic pressure and the action of the sodium and chloride ions on the membrane of the yeast cells (14). Salt gives the baker a tool to control the production of carbon dioxide gas and the other products of fermentation, especially in the warm summer months if temperature control is a problem in the bakery. It is well known in the baking industry that salt lengthens the mixing time of dough (Fig. 1). This has been well documented by the farinograph (7,13,17, 21,22,27,29) and in the mixograph (4, 12,24). The longer mix time slows the rate of production in large bakeries that are on tight production schedules and increases the energy cost of mixing. Therefore it is common practice to delay salt addition until the dough has reached the clean-up stage (when the dough forms into a continuous mass and no longer sticks to the sides of the mixer). At this stage the dough is essentially hydrated and the added salt does not affect the time required to finish mixing. Farinograph studies have also shown that salt decreases water absorption (7,13, 21,22,27,29). This effect was not reported in mixograph or baking studies. It is well known that salt has a strengthening effect on dough. This has been documented in the farinograph (7,13,17,22, 27,29), mixograph (4,12,24), ex t ens ig r aph (21,27), and baking studies (5,6,9). FEATURE

Effect of formula water content on the spread of sugar-snap cookies

ABSTRACT Sugar-snap cookie doughs prepared with a commercial soft wheat flour and standard formula water (25%, fwb) produced baked cookies with a mean diameter of 186 mm. Increasing the formula water to 30% resulted in cookies with a mean diameter of 187 mm and decreasing the formula water to 20% resulted in cookies with a mean diameter of 185 mm. A similar effect was seen when the formula water in cookie doughs prepared with the pure hard red spring cultivar Butte 86 or the pure soft white winter club cultivar Paha was varied. Thus, varying the formula water in cookie dough appeared to have little or no effect on final cookie diameter. Formula water content, however, did affect cookie dough spread rate and set time during baking. Increasing the formula water caused the spread rate to increase but shortened the set time. As a result, final cookie diameter was essentially unchanged.

Effects of (1→3)(1→4)-β-D-glucans of wheat flour on breadmaking

ABSTRACT Water-soluble nonstarch polysaccharides were extracted from commercial hard red winter wheat flour and separated into three fractions by graded ethanol precipitation. The three fractions, F15, F40, and F60, varied in polysaccharide composition. Fraction F15 was rich in watersoluble (1→3)(1→4)-β-d-glucans, and fractions F40 and F60 were rich in arabinoxylans. Addition of individual fractions to a bread formula did not affect bread loaf volume. Addition of fraction F15 to the formula improved bread crumb grain. Treatment of (1→3)(1→4)-β-D-glucan-rich fraction F15 with lichenase before its addition to the bread formula resulted in bread with poor crumb grain. Treatment of the F15 fraction with β-xylanase before its addition to the bread formula resulted in bread with slightly improved crumb grain. Presumably, the (1→3)(1→4)-β-D-glucans in fraction F15 improved crumb grain by stabilizing air cells in the bread dough and preventing coalescence of the cells. Addition of pentosan-rich fractions F40 and ...

Role of hydrogen peroxide produced by baker's yeast on dough rheology

ABSTRACT Bakers yeast, Saccharomyces cerevisiae, has a well-known effect on dough rheology during breadmaking. During a 3-hr fermentation, hydrogen peroxide (H2O2) produced by yeast (0.76%, fwb) increased from 1.09 to 2.32 μmol/g of flour. The spread test, a measure of a doughs rheological properties, showed that yeast had an effect on dough rheology similar to that of H2O2, an oxidant that makes flour-water dough more elastic. In additional experiments (spread test and H2O2 measurement), glucose oxidase, an enzyme that produces H2O2, gave results similar to those with yeast. The fact that catalase, an enzyme that destroys H2O2, reversed the rheological effect of added H2O2 but did not reverse the effect of either yeast or glucose oxidase suggested that either wheat flour contains an inhibitor to catalase or H2O2 was not the active component. A series of experiments, including use of defatted flour, remixing, and mixing dough under nitrogen, all indicated that catalase was inhibited by peroxides in the ...

Modified Wheat Starches Increase Bread Yield

The yield of bread (amount of bread produced from a given weight of flour) is important to the commercial bread baker. Adding more water into the dough formula is an effective method of increasing bread yield with essentially no increase in processing costs. Thus, increased dough absorption is important from an economic point of view. According to the United States Food and Drug Administration Code of Federal Regulations (http://www.cfsan.fda.gov), standardized white bread produced in the United States can contain up to 38% water (USDA 2003). With most flours, it is not possible to add sufficient water in the formula to obtain bread with a final moisture content of 38%. Dough that contains excess water becomes wet and sticky and cannot be processed. In general, the amount of water lost during baking is controlled by a number of factors. These include oven temperature, baking time, surface area of the bread, and water absorption of the dough. Increased water absorption leads to higher moisture in the resulting bread and increased bread yield (Tipples and Kilborn 1968; Czuchajowska et al 1989; Puhr and D’Appolonia 1992). Dough size and shape, oven temperature, and baking time are essentially fixed in a commercial bakery. Therefore, increasing water absorption is the most practical way to increase bread yield. The water absorption of flour is determined by a number of factors including the levels of protein, arabinoxylans, and damaged starch present in the flour. Tipples and Kilborn (1968) reported that increased starch damage level and the accompanying increase in dough water absorption led to an increase in bread yield. Damaged starch imbibes water and swells at room temperature. Thus, a low level (≈5% fwb) of damaged starch has a positive effect on dough by increasing water absorption. However, at high levels (>8% fwb), the damaged starch granules interact with the gluten and change the rheological properties of the dough. The dough becomes strong but loses its elastic character. The dough is unable to expand normally during proofing and oven spring, resulting in loaves with reduced loaf volume and poor crumb grain. Added αamylase can overcome this problem by degrading the damaged starch to decrease the interaction and improve oven spring. This is the major advantage of adding α-amylase to bread flour. The degradation of the damaged starch by α-amylase also releases some of the water held by the damaged granules. Therefore, if the damaged starch level is too high, the dough becomes wet and sticky during fermentation and may produce bread with a sticky crumb. Starch can be chemically or physically modified to alter its physical properties and make it more useful in certain applications. Modifications that are commonly performed and the properties of the resulting modified starches are discussed by BeMiller (2007) and Miyazaki et al (2006). Certain of the modified starches, including pregelatinized starches, imbibe water and swell at room temperature in a manner similar to that found with damaged starch. The majority of the modified starches available are produced from corn starch. Corn starch is not compatible with gluten in breadmaking; however, wheat, rye, and barley starches are compatible with gluten (Hoseney et al 1971). Thus, modified wheat starch would be preferred in breadmaking. It is possible that certain modified wheat starches and, particularly, pregelatinized modified wheat starches might increase dough absorption in a manner similar to damaged starch but without the drawbacks described above. The modified starch may be less reactive with the gluten protein and, thus, have less effect on dough rheology. It is also possible that the modified starch would be a poorer substrate for α-amylase and not be as severely degraded during fermentation. Another approach to increasing dough absorption would be the use of the enzyme glucose oxidase which has been reported to increase dough absorption (Vemulapalli et al 1998). The objectives of this study were to determine whether bread yield could be increased by adding modified wheat starch or pregelatinized modified wheat starch to the bread formula. In addition, the effect of glucose oxidase added in combination with pregelatinized modified starch was studied.

Use of elongational viscosity to estimate cookie diameter

ABSTRACT Cookie diameter is a function of spread rate and set time during baking. Dough viscosity appears to control cookie spread rate and, thus, will affect final cookie diameter. The technique of lubricated uniaxial compression was used to measure the elongational viscosity of cookie dough. Full-formula cookie doughs made with a commercial hard wheat flour had a significantly higher elongational viscosity (5.88 × 106 ± 9.17 × 104 Pa·S) than cookie doughs made with a commercial soft wheat flour (2.17 × 106 ± 1.05 × 104 Pa·S). Elongational viscosity correlated significantly (P < 0.05) with the diameter (r = -0.796) of cookies made with flours from various soft wheat cultivars. Using a simplified cookie formula decreased the testing time without greatly changing the correlation coefficient (r = -0.738). Thus, lubricated uniaxial compression appears to be an appropriate technique to measure the viscosity of cookie doughs and may be useful for predicting the cookie baking quality of soft wheat flours.

Effect of RS4 Resistant Starch on Extruded Ready-to-Eat (RTE) Breakfast Cereal Quality

ABSTRACT A phosphorylated cross-linked type 4 resistant wheat starch (RS4) containing 85.5% total dietary fiber (TDF) replaced 5–20% of the whole corn flour in an extruded ring-shaped ready-to-eat breakfast cereal formulation. TDF content of the dry ingredient blend increased by roughly 3.6% for every 5% of added RS4. TDF loss during extrusion processing increased as RS4 level increased; however, a high percentage (78–89%) of the TDF content was retained in the final product. Product density increased as level of RS4 increased, but no effect on the specific mechanical energy was observed. X-ray microtomography showed that RS4 addition did not affect internal air-cell wall thickness, air-cell size, or porosity. Moreover, addition of 5 or 10% RS4 did not affect expansion, physical appearance, initial crispness, or bowl life of the cereal rings. High levels of RS4 (15 and 20%) decreased cereal ring diameter but increased initial (dry) product crispness and extended bowl life. In general, RS4 addition level d...

Consumer Sensory Analysis of High Flavonoid Transgenic Tomatoes

UNLABELLED Tomatoes have ameliorative effects on cardiovascular disease and cancer. In this study, metabolic engineering of flavonoids was utilized to improve the nutritional value of tomatoes by increasing flavonol and anthocyanin content. Total flavonol content was significantly increased in both the peel and flesh using the onion chalcone isomerase (CHI) gene. The Delila (Del) and Rosea1 (Ros1) genes from the snapdragon Antirrhinum majus were concomitantly expressed to produce an anthocyanin-rich tomato which was purple in color. Sensory evaluation by a panel of 81 untrained consumers revealed no significant difference in liking of color or texture between CHI, Del/Ros1, and wild-type tomatoes. Consumers reported marginal but significantly higher preference for the flavor and overall liking of CHI tomatoes over Del/Ros1 and wild-type tomatoes. This study is the first to report the results of sensory tests of transgenic tomatoes by a consumer panel representing the general consuming public. PRACTICAL APPLICATION Transgenic procedures were used to increase the flavonol and anthocyanin contents of tomatoes. An untrained consumer panel scored flavor and overall liking of the 2 transgenic tomatoes higher than wild-type tomatoes and reported no difference in liking of texture or color between the 3 tomatoes. After participating in the sensory study, 14% of the panelists changed their attitudes positively toward transgenic vegetables and 96% of the consumers on the panel reported that they would buy transgenic food if they believed that it would promote health.

Sodium Reduction in Bread Using Low-Sodium Sea Salt

ABSTRACT Yeast bread is a major contributor of sodium in the American diet. Because of its functional impact on dough rheology and the quality of the final baked product, simply reducing the level of sodium chloride (salt) in the formula or replacing it with salt substitutes has found minimal success. The objective of this study was to determine the effect of sea salt containing 57 or 64% less sodium than common sea salt on the breadmaking properties and consumer acceptability of bread. The sodium content of the salt had no effect on dough strength, mixing time, gas production, loaf volume, or crumb grain. The flavor and overall liking of breads containing sea salt with 57 and 64% less sodium content were scored only slightly lower than bread containing the control salt by an untrained panel of 118 consumers. No difference in texture and no unacceptable flavor notes in the bread made with reduced-sodium salts were reported. Thus, it appears that use of reduced-sodium sea salt is a satisfactory alternative...