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The consumption of recommended amount of dietary fiber is a challenge not only for most consumers but also for the food scientists to design fiber-enriched foods with acceptable eating quality, texture, color and flavor. The addition of psyllium husk (PS) significantly made the bread texture softer with increasing levels, producing the lowest compression force value (2.48 ± 0.37 N) at a 5% level. Addition of coarse wheat bran (at 10 and 20% levels) to white wheat flour (WWF) produced a significantly softer bread texture (4.65 ± 0.61 to 5.27 ± 0.32 N) compared with the harder texture with the fine wheat bran addition (5.04 ± 0.33 to 6.82 ± 0.57 N) for the control samples, respectively. When psyllium at 5% level was added to either the WWF or wholegrain wheat flour (WGF), it produced a significantly softer bread texture. Interestingly, the incorporation of diacetyl tartaric acid esters of mono- and diglyceride (DATEM) emulsifier (0.5%) in the WWF or WGF bread samples containing 5% psyllium did not significantly improve the textural properties of bread samples. When WWF + 5%PS (4.03 ± 0.12 N) buns were compared with WGF + 5%PS, the WGF +5%PS buns (7.37 ± 0.16 N) had a significantly harder texture. The results of compression force (N) and higher consumer acceptability values of these products clearly brought out the superior textural properties of wheat pan bread and buns made by this newer approach, than the common approach of using only the wholegrain wheat flour. Future studies on the effect of various wheat bran treatments, such as steaming or extrusion on the textural properties of pan bread and buns are recommended.

Electron paramagnetic resonance (EPR) spectroscopy has emerged as a fast, reliable, non-invasive and sensitive method to determine the distribution, localization and reactivity of labelled ingredients in micro-heterogeneous systems. However, the commercially available probe molecules are very limited. In the present work, five new nitroxide [(4-hydroxy-2, 2, 6, 6-tetramethylpiperidin-1-oxyl (TEMPOL)] derivatives (1b-5b) of diacetyl tartaric acid esters of monoglycerides (DATEM) (1a-5a), a widely used food emulsifier, were synthesized under Steglich conditions and characterized by MS (mass-spectrometry), FT-IR (Fourier-transform infrared spectroscopy), EPR, NMR (nuclear magnetic resonance spectroscopy), fluorescence spectroscopy, and DSC (differential scanning calorimetry) analysis. Phase partitioning studies proved that the new spin labels are adequately capable of describing the localizations and partitioning of the corresponding DATEM in multi-phase systems. Findings disclosed in this work will provide new knowledge on ingredient reactivity and localization in multi-phase systems; which is vital to aid the design of more efficient delivery systems for bioactive compounds.

Background Despite the associated health benefits of whole grains, consumption of whole grain products remains far below recommended levels. Whole wheat bread is often associated with many distinctive attributes such as low loaf volume, firm and gritty texture, dark and rough crust and crumb appearance, bitter flavor, and reduced shelf-life. There is a need to improve its quality and sensory characteristics so as to increase consumer appeal and, ultimately, increase the intake of whole wheat bread. The inclusion of various ingredients improves dough and bread properties. Scope and approach This review examines the effects of enzymes, emulsifiers, hydrocolloids, and oxidants on the properties of whole wheat bread and dough, with particular attention to effects on loaf volume and hardness. Wheat gluten and other plant materials are also discussed. Gaps in the research into whole wheat bread are identified, and future research needs are recommended. Key findings and conclusions Xylanase reduces the water absorption of whole wheat flour and increases loaf volume and crumb softness by hydrolyzing ararbinoxylans. α-amylase can be beneficial under certain conditions. Phytase may activate endogenous α-amylase. G4-amylase is promising but needs validation by further research on its effect on loaf volume, crumb hardness, and staling. Vital wheat gluten overcomes many of the challenges of whole wheat bread production and is found in the majority of commercial whole wheat breads. Emulsifiers DATEM and SSL can improve the volume, texture and staling profile of whole wheat bread. Several types of improvers are generally needed in combination to provide the greatest improvement to whole wheat dough and bread.

Hydrophobicity was introduced in the structure of guar gum (GG) by esterification with n-octenyl succinic anhydride (OSA), forming GG-OSA. This modification was evaluated by FTIR. Maximum degree of substitution of 0.025 was achieved by reacting GG with 0.4 mol OSA/mol of repeating unit of GG at 100 °C for 5 h using 0.5 equivalence of NaHCO3. This GG-OSA, with the introduced partial hydrophobicity, was evaluated for its effect on bread staling and glycaemic index (GI), primarily in comparison to diacetyl tartaric and fatty acid esters of glycerol (DATEM) and GG, respectively. GG-OSA demonstrated potential bread dough strengthening ability by improving its cohesiveness and hardness. On day 4, X-ray diffraction studies on bread containing GG-OSA at 2.5 g/kg (4.10%) indicated crystallinity closer to that containing DATEM at 4 g/kg (4.24%) and lower than control (6.86%) and GG (5.26%). This was corroborated with day 4 crumb firmness for breads containing GG-OSA (18.29 N) and DATEM (19.92 N). The GI of control bread was higher than experimental samples, although there was no statistically significant difference between samples containing the additives chosen in this study. Thus GG-OSA could be used as an effective anti-staling agent in bread.

The effect of amphoteric (lecithin), non-ionic (GMS) anionic (SSL and DATEM) surfactants at 0.25, 0.5 and 1% level on short biscuit dough containing multifaceted protein matrix due to the presence of multigrain and biscuit baking quality were carried out. The dough texture profile analysis (TPA), biscuits physical, textural, microstructural and sensory properties were studied to select the suitable surfactant for multigrain biscuits. Surfactants significantly (P ≤ 0.05) decreased the TPA dough hardness to varying levels from 91.63 N for control to 69.23 N (lecithin), 67.06 N (GMS), 78.93 N (SSL) and 81.13 N (DATEM) respectively at the 1% level. The springiness of the dough increased with the addition of surfactants indicating increased dough strength by interacting with protein and starch. Lecithin and GMS significantly affected all the color parameters, whereas SSL and DATEM did not show any considerable difference even at the 1% level. Biscuit weight, thickness and breaking strength decreased and diameter, spread ratio increased with the addition of surfactant. GMS showed maximum improvement in spread ratio and breaking strength even at 0.25% (10.05) and 0.5% (10.65) level compared to other surfactants at the same level. SEM studies indicated that addition of lecithin and GMS, starch granules appeared partially gelatinized, whereas SSL and DATEM improved the continuity of protein matrix and intact starch granules are embedded on it. Sensory studies indicated that among different surfactants, GMS at 0.5% level showed maximum improvement in all the sensory parameters and these biscuits had golden brown color, smooth surface, crisp texture and highest OAA.

Wheat gluten was isolated in a laboratory dough-batter flour separation process in the presence or absence of lipases differing in hydrolysis specificity. The obtained gluten was blended with wheat starch to obtain gluten-starch (GS) blends of which the water and oil binding capacities were investigated. Furthermore, GS blends were mixed into dough and processed into model breads, of which dough extensibility and loaf volume were measured, respectively. In comparison to GS blends prepared with control gluten, oil binding capacity was higher when GS blends contained gluten isolated with Lecitase Ultra (at 5.0 mg enzyme protein/kg flour), a lipase hydrolyzing both non-polar and polar lipids. Additionally, dough extensibility and total work needed for fracture were lower for dough prepared from GS blends containing gluten isolated with Lipolase (at 5.0 mg enzyme protein/kg flour), a lipase selectively degrading non-polar lipids. In GS blend bread making, this resulted in inferior loaf volumes. Comparable GS blend properties were measured when using control gluten and gluten isolated with YieldMAX, a lipase mainly degrading N-acyl phosphatidylethanolamine. In conclusion, properties of GS blend model systems are altered when gluten prepared in the presence of lipases is used to a degree which depends on lipase specificity and concentration.

The effect of the addition of flaxseed oil (FO), phytosterols (PS) and polydextrose (PDX) on the physicochemical and sensory properties of milk was investigated, as they are known to impart health benefits.; Results: For incorporating PS, a hydrophobic substance, FO and milk fat (MF) as an oil source, an emulsifier (DATEM) and PDX solution as an aqueous medium were used for the preparation of emulsion. Three emulsion formulations A (8 g PS, 8 g FO, 20 g PDX, 6 g MF), B (10 g PS, 10 g FO, 20 g PDX, 4 g MF) and C (12 g PS, 12 g FO, 20 g PDX, 2 g MF) were prepared and added individually to milk at a level of 50 g kg-1 . Based on sensory evaluation, formulation B was selected for fortification of milk. The fortified milk kept well at refrigerated temperature for 1 week, and changes in sensory, physicochemical and microbiological properties were comparable to those of control milk. The level of fortificants did not decrease in the milk after 1 week of storage.; Conclusion: An emulsion containing FO, PS and PDX could successfully serve as a potential delivery system for enhancing the nutritional and therapeutic potential of milk. © 2017 Society of Chemical Industry.; © 2017 Society of Chemical Industry.

The objective of the present study was to evaluate the effect of enzymes (xylanase and amylase) and emulsifiers (SSL and DATEM) on the rheological properties of dough and physicochemical, textural, microstructural, nutritional, as well as sensory attributes of whole wheat bread (WWB). Based on the results, the combination of xylanase and emulsifiers had a synergetic influence on the dough rheology and bread attributes due to the interactions among enzyme-emulsifiers and bread ingredients. Incorporating xylanase, SSL, and DATEM into the whole wheat bread formulation significantly enhanced the stability, extensibility, total antioxidant activity, and general acceptability, while phytic acid content and hardness of the final bread were decreased. Regarding SEM analysis, a more homogeneous and uniformed texture was observed in the samples containing xylanase and emulsifiers, compared to the bread without any additives. On the other hand, amylase demonstrated no strengthening effect on whole wheat bread, this could be explained by its influence on the starch decomposition. WWB prepared with a combination of enzymes and emulsifiers was given higher scores in the organoleptic parameters. In conclusion, fortification of whole wheat bread with xylanase, amylase, SSL, and DATEM can play a positive role in the quality as well as the nutritional value of WWB.

The aim of this study was to correlate dielectric properties with quality parameters, and to optimize cake formulation and baking conditions by response surface methodology. Weight loss, color, specific volume, hardness and porosity were evaluated. The samples with different DATEM (0.4, 0.8 and 1.2%) and chickpea flour concentrations (30, 40 and 50%) were baked in microwave oven at different power (300, 350, 400 W) and baking times (2.50, 3.0, 3.50 min). It was found that microwave power showed significant effect on color, while baking time showed effect on weight loss, porosity, hardness, specific volume and dielectric properties. Emulsifier level affected porosity, specific volume and dielectric constant. Chickpea flour level affected porosity, color, hardness and dielectric properties of cakes. The optimum microwave power, baking time, DATEM level and chickpea flour level were found as 400 W, 2.84 min, 1.2% and 30%, respectively. The comparison between conventionally baked and the microwave baked cakes at optimum points showed that color difference, weight loss, specific volume and porosity values of microwave baked cakes were less than those of conventionally baked cakes, on the other hand, hardness values were higher. Moreover, a negative correlation between dielectric constant and porosity, and weight loss values were detected for microwave baked samples. A negative correlation between dielectric loss factor and porosity was observed. These correlations indicated that quality characteristics of a microwave baked cake sample can be assessed from dielectric properties. These correlations provides understanding on the behavior of food material during microwave processing.

Fractionation of lipase-treated wheat lipids showed that polar lipase-reaction products were responsible for their positive functional effects in breadmaking. The results allowed the conclusion that an optimal baking lipase preferably hydrolyzes monogalactosyl diglycerides and N-acyl phosphatidyl ethanolamine, but has only moderate activity towards digalactosyl diglycerides. Synergistic effects of digalactosyl diglycerides and their products digalactosyl monoglycerides (molar proportion 1:1) provide even a greater bread volume increase. Reconstitution baking (defatted flour plus lipid or lipid fraction added) partly provided contradictory results. 100% polar lipase-treated lipids were less active than untreated polar dough lipids plus polar flour lipids. Combinations of non-polar and polar lipase-treated lipids were even more active than the polar ones alone. It appears that the polar reaction products of baking lipases need the presence of unmodified lipids or non-polar lipids to provide optimal functional effects. The present data suggests that synergistic effects between different lipid classes might play a key role in the mechanism of action of baking lipases.

The objective of this study was to evaluate the effect of hydrocolloids and/or emulsifiers on the shelf-life of composite cassava-maize-wheat (ratio 40: 10: 50) reference bread during storage. Added hydrocolloids were carboxymethylcellulose (CMC) and high methoxyl pectin (HM pectin) at a 3% level (w/w) and/or the emulsifiers diacetyl tartaric acid esters of monoglycerides (DATEM), lecithin (LC), and monoglycerides (MG) at a 0.3% level (w/w). After 4 days of storage, composite breads with MG had comparatively lower crumb moisture while crumb density was similar in all breads. The reference bread crumb firmness was 33.4 N, which was reduced with an addition of DATEM (23.0 N), MG (29.8 N), CMC (24.6 N) or HM pectin (22.4 N). However, the CMC/DATEM, CMC/LC, and HM pectin/DATEM combinations further reduced crumb firmness to < 20.0 N. The melting peak temperature was increased from 52 degrees C to between 53.0 degrees C and 57.0 degrees C with added hydrocolloids and/or emulsifiers. The melting enthalpy of the retrograded amylopectin was lower in composite bread with hydrocolloids and emulsifiers, 6.7-11.0 J/g compared to 20.0 J/g for the reference bread. These results show that emulsifiers in combination with-hydrocolloids can improve the quality and extend the shelf-life of composite cassava-maize-wheat breads.

Thepla is Indian unleavened flatbread made from whole-wheat flour with added spices and vegetables. In the present study, effect of addition of various emulsifiers such as sodium stearoyl-2-lactylate (SSL), di acetyl tartaric acid ester of monoglyceride (DATEM) and glycerol mono-stearate (GMS) were studied. Further hydrocolloids (guar gum, carrageenan) and modified polysaccharides [hydroxypropyl methylcellulose (HPMC) and carboxymethyl cellulose] were added at the concentration ranging from 0.25 to 1 % on the basis of whole wheat flour to prepared the doughs. These thepla doughs were analyzed for rheology and theplas were analyzed for tear force. Additives helped in improvement of dough and thepla quality. Guar gum increased dough stickiness and strength to the highest (31.12 and 1.76 g respectively). Also, guar gum decreased tear force value of thepla to 208.4 g. Tear force was found to be increasing with the duration of storage. Highest improvement in thepla dough and quality was obtained by the addition of guar gum at 0.75 % which retained the softest texture of thepla.

The effect of three enzymes on the rheology and the baking performance of bread dough with high content of resistant starch (RS) was studied. The RS was added as an alternative to increase the fiber ingestion while the enzymes, to make up the gluten dilution. A full factorial 23 design with central point in triplicate was applied with dough formulated with partial substitution of wheat flour by RS (12.5 g/100 g) and the enzymes: transglutaminase (0–8 mg/100 g), glucose-oxidase (0–5 mg/100 g) and xylanase (0–1 mg/100 g). Dough produced without RS or enzymes was considered as regular and dough produced with RS and without enzymes was considered as control for comparison. Bread was produced from regular, control and optimum formulations and the quality was assessed concerning specific volume, firmness and preference by sensory panel. Enzymes had significant effect (p

The aim of this study was to evaluate the effects of two emulsifiers, sodium stearoyl-2-lactylate (SSL) and diacetyl tartaric acid esters of mono and diglycerides (DATEM) on the physical and textural characteristics of gluten-free (GF) cheese bread and the influence they have during storage. DATEM and SSL in percentages of 0.5 and 1.0 were added based on the amount of cheese in the formula. The dough behaved as a viscoelastic solid, adjusting itself to a model consisting of three Maxwell elements with a spring in parallel. The results indicate that emulsifiers had no significant effect on dough rheology. The emulsifiers affected the physical and textural characteristics of GF cheese bread. The height, diameter and specific volume of the samples decreased with higher concentrations of emulsifiers in the formula, while the yield and crumb hardness increased. Crust fracture and crumb hardness of samples increased during storage, thus the emulsifiers did not control product aging. Practical Applications Large-scale production and the rise in consumers that demand good-quality GF products have brought about the need to use food additives, such as emulsifiers, which are used as antiaging agents in bakery products by increasing their shelf life. Few studies have been carried out into the use of emulsifiers in GF products. For this reason, it is considered of great importance to evaluate the effect that these additives have on GF cheese bread, which is made by blending mainly sour cassava starch, water or milk, cheese, salt, sugar and fat. This product has a large market in South America and could be an alternative for celiac patients in that region.

While endogenous wheat lipids exert a major effect on bread quality, little is known on the way they impact on bread loaf volume (LV). Here we altered wheat flour lipid composition during bread making using lipases in situ. Lipopan F, Lecitase Ultra, and surfactants increased LV to similar extents. The increases in bread LV as a result of these enzymes were related to decreased levels of galactolipids and phospholipids and concomitant increased 'lyso'-lipid as well as free fatty acid (FFA) levels. The FFA formed were transferred to the free lipid fraction, while the 'lyso'-lipids remained in the bound lipid fraction. For optimal gas cell stabilisation, an equilibrium between the lipid classes present and hence, the type of mesophase formed, is essential. Sufficient levels of lipids forming lamellar mesophases and lipids forming hexagonal I mesophases, which respectively form condensed monolayers or emulsify (deleterious) non-polar lipids in dough liquor, are needed.

Effects of some enzymes (transglutaminase; TG and glucosoxidase; GO), emulsifiers (sodium stearoyl-2-lactylate; SSL, diacetyl tartaric acid esters of mono and diglycerides; DATEM, and SSL+DATEM combination) and oxidant (ascorbic acid; AA) on the properties of dough and bread made of a wheat flour (WF) and lupin flour (LF) blend were determined. LF replaced with WF at a 15% level in all dough formulation. All additives except TG increased development time and stability of dough containing 15% LF. While the highest dough energy obtained with AA addition, maximum resistance value increased from 217 BU up to 434 BU with TG usage in dough formulation. SSL+DATEM combination gave highest bread volume and lowest crumb hardness at 24 and 72 h. Generally, SSL+DATEM and AA had a more positive effect on symmetry, pore structure and crumb texture of the bread than the other additives. For improvement of the properties bread prepared with WF-LF blend, SSL+DATEM combination as emulsifier and AA as oxidant can be recomme...

The effect of selected monoglycerides on droplet morphology and rheology of palm kernel oil emulsions was studied. Combination of lactic acid ester of monoglycerides (LACTEM) and unsaturated monoglycerides (GMU) yielded highly viscous emulsions caused by partial coalescence. LACTEM combined with saturated monoglycerides (GMS) or diacetyl tartaric acid ester of monoglycerides (DATEM) gave low-viscous emulsions. The rheological behavior was found not to be related to polymorphic transformations of fat in the emulsions. A possible relationship between structural changes of emulsions and the effect of monoglyceride crystallization behavior of PKO was examined by studying the monoglycerides' influence on crystallization of bulk PKO. Polymorphic transformation, crystallization kinetics and melting/crystallization profile of bulk PKO were analyzed. The monoglycerides had minor effect on crystallization behavior of bulk PKO compared to the major impact on emulsion stability. This indicates that emulsifiers act differently in bulk and dispersed fat. For PKO the structural changes of the emulsions were independent of the effects of monoglycerides on the crystallization of bulk fat.

Wheat germ (coarse and fine) was replaced with wheat flour at levels of 0, 10, 20 and 30% for cake making. Sodium stearoyl-2 lactylate (SSL) and diacetyl tartaric acid esters of mono (and di) glyceride (DATEM) were used as emulsifier at 0.5% level. The effects of wheat germ particle size, emulsifier type and wheat germ level on batter and cake quality were investigated. Coarse wheat germ (CWG) usage in cake formulation gave better cake physical properties than fine wheat germ (FWG). SSL provided higher cake volume, texture and pore structure score, and lower hardness to cake samples compared with DATEM. Wheat germ addition (CWG/FWG) increased the ash, protein, fat and mineral contents (Ca, Cu, Fe, Mg, Mn, P, K and Zn) of the samples. Crust and crumb color of the cake samples were significantly (P

In order to improve processing performance and functionality of wheat flour dough, the influence of emulsifiers including distilled mono-glycerides (DMGs), polysorbate-60 (P60), and diacetyl tartaric esters of mono-glycerides (DATEM) on dough rheological properties and quality of fried instant noodles have been investigated. Farinograph, extensograph, and scanning electron microscopy analysis were conducted to characterize the dough rheological property. The addition of P60 and DATEM in dough strengthened its rheological properties, being indicated by high stability, low degree of softening within 12 min, increase in resistance to extension, and enhancement of extensibility in comparison with the control. The quality of noodle including sensory, water content, degree of gelatinization, and oil content was evaluated. As compared to the control, the oil content in fried instant noodle with the addition of 0.2 g P60/100 g and 0.2 g DATEM/100 g flour reduced 18.3% and 9.9%, respectively; the time of rehydration decreased 25.0% and 12.5%, respectively; and the degree of gelatinization increased 10.2% and 8.1%, respectively. Both P60 and DATEM showed a significant impact on springiness, firmness, and overall acceptability in noodles. The results clearly indicate that dough rheological characteristics and quality of noodles improved with the addition of certain emulsifiers.

Bread baking from wheat and millet flours in different ratios was investigated. Optimisation of bread quality produced from a wheat/millet composite flour in the ratio 50:50 was pursued by adding emulsifiers and enzymes. Higher millet addition (30 g/100 g and up) asked for higher dough moisture. Addition of emulsifiers (combination of DATEM and distilled monoglycerides) had significant effects on volume, crumb firmness, relative elasticity and number of pores in the crumb. Emulsifier addition allowed increasing the share of millet within the wheat/millet composite flour. Xylanase exerted a crumb softening effect, which was adversely affected by transglutaminase addition, but transglutaminase improved crumb pore structure and both enzymes increased bread volume. Combined addition of xylanase and transglutaminase significantly increased volume of a 50:50 wheat/millet bread by 25%. Overall, by the addition of emulsifier and enzymes bread could be produced from 50:50 wheat/millet flour, which was of acceptable quality.

Changes in the secondary structure of gluten proteins due to emulsifiers were analyzed by Raman Spectroscopy. The protein folding induced by 0.25% SSL (Sodium Stearoyl Lactylate) (GS0.25, Gluten + 0.25% SSL) included an increase in alfa-helix conformation and a decrease in beta-sheet, turns and random coil. The same behavior, although in a less degree, was observed for 0.5% gluten?DATEM (Diacetyl Tartaric Acid Esters of Monoglycerides) system. The low burial of Tryptophan residues to a more hydrophobic environment and the low percentage area of the C?H stretching band for GS0.25 (Gluten + 0.25% SSL), could be related to the increased in a-helix conformation. This behavior was also confirmed by changes in stretching vibrational modes of disulfide bridges (S?S) and the low exposure of Tyrosine residues. High levels of SSL (0.5% and 1.0%) and DATEM (1.0%) led to more disordered protein structures, with different gluten networks. SSL (1.0%) formed a more disordered and opened gluten matrix than DATEM, the last one being laminar and homogeneous. Fil: Gómez, Analía Verónica. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Universidad Nacional de la Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Agrarias y Forestales; Argentina Fil: Ferrer, Evelina Gloria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Química Inorgánica "Dr. Pedro J. Aymonino". Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Centro de Química Inorgánica "Dr. Pedro J. Aymonino"; Argentina Fil: Añon, Maria Cristina. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Universidad Nacional de la Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos; Argentina Fil: Puppo, Maria Cecilia. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Universidad Nacional de la Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Agrarias y Forestales; Argentina

The present study investigated the effect of emulsifiers on complexation, pasting, and gelling properties of native and chemically modified white sorghum starches. Chemically modified starches demonstrated better capability to complex with glyceryl monostearate (GMS) compared to diacetyl tartaric acid ester of mono- and diglycerides (DATEM) and sodium stearoyl lactylate (SSL) due to its non-ionic and hydrophobic nature. The results revealed that addition of emulsifiers to native and modified starches altered both the textural properties and ageing characteristics of starch gels during cold storage. Firmness rate enhanced on addition of emulsifiers to native white sorghum starch (NWSS) whereas it reduced when added to acetylated white sorghum starch (AWSS) and dual modified acetylated-oxidized white sorghum starch (AOWSS). Cold paste viscosities of NWSS, AWSS, and AOWSS were also found to be higher in the presence of emulsifiers. The decline in paste clarity on refrigerated storage was significantly curtailed on incorporation of emulsifiers to NWSS, AWSS, and acid-thinned white sorghum starch (ATWSS) which implies reduction in the rate of retrogradation.

The effect of addition of three commonly used emulsifiers namely GMS (glycerol monostearate), SSL (sodium stearoyl lactylate) and DATEM (diacetyl tartaric acid esters of monoglycerides) on complexation, thermal, pasting and textural properties of OWSS (oxidized white sorghum starch) was studied. The study is of interest as both oxidized starches and emulsifiers are present as co-ingredients in different food products and thus their complexation could affect the textural characteristics of foods. The complexation index (CI) reduced on oxidation of sorghum starch. The CI for native white sorghum starch (NWSS) was in the order GMS > SSL > DATEM whereas for OWSS, CI was in the order GMS > SSL > DATEM. Presence of emulsifiers significantly reduced gelatinization enthalpies of starches. Types I and II amylose–lipid complexes were observed in NWSS and OWSS on addition of GMS. Pasting temperature of NWSS increased while peak viscosity reduced on addition of SSL and GMS. Cold paste and setback viscosities of OWSS increased significantly (p ≤ 0.05) on addition of emulsifiers. Emulsifiers reduced firmness and rupture strength of NWSS and OWSS gels. Increase in firmness of gels on storage increased in NWSS and decreased in OWSS on addition of emulsifiers. Elasticity of OWSS on cold storage was higher in the presence of SSL and GMS.

Mixed colloidal dispersions, consisting of starch granules and lipid droplets, were used as model systems to represent commercial food products, such as sauces, desserts, and soups. Colloidal dispersions were prepared by mixing unheated modified starch (3.5 or 5.0 wt%) and lipid droplets (2.5, 5.0 or 8.0 wt% oil) together and then heating (90 °C for 5 min) to promote starch gelatinization. The lipid droplets were stabilized by a food-grade surfactant consisting of a mixture of diacetyl tartaric acid ester of mono-diglycerides (DATEM) and mono-diglycerides. The influence of thermal processing and composition (starch, lipid, surfactant content) on the particle size, microstructure, lightness, and shear viscosity of the model sauces was examined. There was a pronounced increase in shear viscosity upon heating, which was attributed to the swelling of the starch granules leading to a close-packed particle suspension. The shear viscosity and lightness of the colloidal dispersions increased with increasing starch and fat content, with fat droplets dominating lightness and starch granules dominating viscosity. The amount of surfactant present also influenced the rheology of the mixed colloidal dispersions, which was attributed to its ability to modify starch granule interactions. Overall, these results have important implications for designing high quality emulsion-based food products, such as soups, sauces, desserts, and beverages.

The effect of emulsifiers on complexation and retrogradation characteristics of native and chemically modified white sorghum starches was studied. Complex forming tendency of white sorghum starch with commercially available emulsifiers GMS and DATEM improved after acetylation. Presence of emulsifiers reduced λ max (wavelength of maximum absorbance) both for native and modified sorghum starches suggesting lower availability of amylose chains to complex with iodine. In native white sorghum starch (NWSS) and oxidized white sorghum starch (OWSS), both Type I and Type II starch–lipid complexes were observed on addition of 1.0% GMS prior to gelatinization. Acetylated-oxidized white sorghum starch (AOWSS) formed weakest complexes among all the modified starches. The results revealed that antistaling characteristics of modified sorghum starches were enhanced when used in combination with emulsifiers. The most prominent decline in reassociative capability among modified starches was observed for acetylated starches.

The aim of this work is to investigate the simultaneous adsorption of a globular protein, ovalbumin, and two different types of food emulsifiers, non-ionic Tween 60 and anionic Admul DATEM, at the air–water and sunflower oil–water interfaces. A commercial non-purified oil was used, aiming at investigating the behaviour of interfaces close to real systems. A pendant drop tensiometer was used to carry out transient interfacial tension measurements and small amplitude oscillations. A constant protein concentration (0.1 g/l) and different emulsifier/protein ratios (ranging between 0 and 0.6) were used during the tests. Experimental results evidenced that the non-ionic emulsifier replaces the protein on the interface (only a partial replacement was observed in the tested conditions) whereas the anionic molecule interacts with the protein forming complexes which can be almost completely replaced by the single emulsifier. The interfacial layers are characterised by a prevalent solid-like behaviour, which proved to be similar to 3D weakly structured systems. The rheological properties are strongly dependent on the nature of both the emulsifier and the interface, nevertheless it was observed that ovalbumin yields a more structured and stronger layer than Admul and Tween. In mixed systems, increasing the emulsifier concentration, the extension of this 2D network decreases whereas the strength seems to be less dependent and evidences only a slight reduction for Admul addition at the A/W interface.

The use of sourdough, even in combination with cryoprotectant (skim milk, sucrose and trehalose), conventional additives (guar gum, diacetyl tartaric acid esters of monoglycerides, ascorbic acid), honey or fructose and glucose, in frozen dough technology was investigated. After frozen storage, the leavening performance of doughs, and the hardness and texture of breads were compared to those of an unfrozen dough, and to those of a conventional frozen dough. All frozen doughs showed a longer fermentation time and a lower volume increase, with respect to unfrozen dough. When sourdough was combined with cryoprotectant, honey or both, the leavening performance improved compared to the use of sourdough alone. Compared to the conventional frozen dough, higher leavening performance was reached combining sourdough with cryoprotectant alone or together with honey. Sourdough combined with honey, fructose and glucose, honey and cryoprotectant, or conventional additives decreased bread hardness compared to the unfrozen dough bread and to the conventional frozen dough bread. Independently from the use of sourdough, conventional additives allowed to reach a specific volume not significantly different from that of unfrozen dough bread, and breads containing honey were characterized by low values of hardness and by high values of red index.

In this study, gluten-free bread formulations using chestnut and rice flours at different ratios (0/100, 10/90, 20/80, 30/70, 40/60, 50/50 and 100/0) were tested. In addition, the influence of hydrocolloid blend (xanthan–locustbean gum (LBG), xanthan–guar gum blend) and emulsifier DATEM on the rheological properties of dough formulations and quality parameters of breads were also investigated for the samples having chestnut/rice flour ratio of 10/90, 20/80, 30/70 and 40/60. Herschel–Bulkley model was found to explain the flow behavior of all dough formulations. The power-law index ( n ) of dough samples at 25 °C ranged from 0.52 to 0.87, the consistency index ( K ) of the samples ranged from 3.6 to 79 Pa s n and the yield stress of the samples ranged from 4.8 to 85.9 Pa. The breads prepared with chestnut/rice flour ratio of 30/70 and containing xanthan–guar blend and emulsifier, had higher quality in terms of hardness, specific volume, color and sensory values. However, elevated levels of chestnut flour led to some deterioration in quality parameters (low volume, harder texture and darker color) regardless of gum blend and emulsifier addition.