Effects of protein and transglutaminase on the preparation of gluten-free rice bread

Effects of transglutaminase (TGase) and proteins such as whey protein, caseinate, and soy protein on the preparation of gluten-free rice breads using non-waxy rice flour were investigated. Rice flour (about 12% moisture content) was prepared from dry milling of dried grain after rice got soaked. Unlike general dry milled flour, newly developed rice flour increased water binding capacity (WBC), swelling power, and peak viscosity. Soy protein increased WBC but other proteins slightly decreased with the increase of levels. Lightness decreased and yellowness increased with the addition of whey and soy protein. All pasting viscosities decreased with the addition of protein. The TGase improved the network structure of rice batter. The 2^nd proof time of rice batter with protein was shortened by 4–9 min with the addition of TGase. The specific volumes of rice breads with whey and soy protein also increased. TGase and protein additions decreased the hardness of rice bread. Sensory test showed that roasted flavor, volume, air cell homogeneity, and overall quality were significantly different (p<0.05) with protein and TGase additions.     

Characteristics and oil absorption in deep‐fat fried batter prepared from ball‐milled wheat flour

BACKGROUND: The porous structure generated during frying influences oil absorption and textural qualities. The alteration in physical properties of wheat flour is suspected to affect the structure formation. The present study investigated the effect of physicochemical changes in wheat flour by the ball‐milling process on structure formation and consequently oil absorption of a fried wheat flour batter model. RESULTS: Batter models containing 600 g kg^?1 moisture were made of 0–10 h ball‐milled wheat flour and then fried in frying oil at 150 °C for 1–7 min. The samples made of milled flour possess larger pores and exhibit lower oil absorption than sample made of 0 h milled flour. The fracture force of a fried sample prepared from 5 and 10 h milled flour is lower than that of a sample prepared from 0 h milled flour. CONCLUSION: The decrease in glass transition temperature (T_g) and melting temperature (T_m) of milled flour affect the microstructure formation in the fried wheat flour batter. The microstructure is responsible for oil absorption and fracturability in fried food. The samples made of flour of longer ball‐milling time have lower oil absorption and higher crispness. Ball‐milling may be a tool to produce mechanically modified wheat flour which can reduce oil absorption for fried batter. Copyright © 2009 Society of Chemical Industry     

Rheological properties of black gram (Phaseolus mungo) batter: characterisation of flour from native and modified rice and their effect on batter viscosity

Rheological properties of black gram batter as a function of soaking time, and effect of flour from native and thermally modified rice on black gram batter have been studied. Greater increase in hydration capacity of black gram dhal was observed during 5–15 min of soaking, a gradual increase up to 90 min and a marginal increase beyond this period. Apparent viscosity of batter showed 100% increase up to 90 min and less than 20% increase beyond 120 min, and shear‐thinning nature of batter indicated that they were pseudo‐plastic in nature. Yield stress and consistency index showed greater changes after 90 min, while flow behaviour index did not show significant change beyond 90 min of soaking. Compared with the addition of native rice flour, incorporation of flaked rice flour and expanded rice flour into black gram batter significantly increased the cold paste viscosity of the batter, probably because of their greater water‐holding capacity, compared with that from native rice. Differences in physicochemical characteristics and pasting behaviour of these flour slurries, as studied by Rapid Visco Analyser, corroborated these results by the typical profile of pregelatinised products for flaked rice and expanded rice in comparison to native rice.     

Particle Size Fractionation of High-Amylose Rice (Goami 2) Flour as an Oil Barrier in a Batter-Coated Fried System

The particle size effects of high-amylose rice (Goami 2) flour on quality attributes of frying batters were characterized in terms of physicochemical, rheological, and oil-resisting properties. High-amylose rice flours were fractionated into four fractions (70, 198, 256, and 415 μm) of which morphology was also analyzed by scanning electron microscopy. Rice flour with smaller particle size exhibited a higher degree of starch gelatinization, giving rise to increased pasting parameters. When the rice flours were incorporated into frying batters, higher steady shear viscosity was observed in the batters with finer rice flour, which could be well characterized by the power law model. In addition, the dynamic viscoelastic properties of the batters were enhanced by the use of rice flour with smaller particle size, which also caused an increase in batter pickup. When subjected to deep fat frying, the batters with finer rice flour exhibited reduced moisture loss. Furthermore, the oil uptake was found to have a positive correlation with the particle size of rice flour (R ²?=?0.88), even showing the reduction of oil uptake by 15%. It could be synergistically attributed to the formation of outer starch granular layers, high batter viscosity/pickup, and reduced moisture loss by finer rice flour.     

Effects of Soy and Corn Flour Addition on Batter Rheology and Quality of Deep Fat-Fried Shrimp Nuggets

In this paper, the effects of soy and corn flour (5 and 10% w/w) addition to the batter formulation on the quality of deep fat-fried shrimp nuggets were evaluated. Rheological properties of batters, coating pick-up, moisture content, and oil content of the samples were determined. Shrimp nuggets were fried at 150 °C, 170 °C, 190 °C, for 1, 2, 3, 4, and 5 min. The coating pick-up, oil and moisture content were found to be directly proportional to batter viscosity. All batters were found to show shear thinning behavior by exhibiting flow behavior index ≤ 1. The batters were modeled as power law fluids. Batter formulation, frying time, and temperature significantly (p < 0.01) affected moisture and oil content of shrimp nuggets. Soy flour added batters provided the highest consistency index, 7.595 and 10.635 Pa.sⁿ for 5% and 10% soy flour added, respectively. Soy flour was found to be an effective ingredient in decreasing oil content of fried nuggets. Batters containing 5% corn flour showed the lowest moisture content and the highest oil content among all the formulations. The mean moisture and fat content of shrimp nuggets coated with batter contained 10% soy and 5% corn flour, fried at 190 °C, for 5 min were 0.59 ± 0.022, 0.480 ± 0.029 and 0.149 ± 0.035, 0.346 ± 0.024 (g/g db), respectively.     

Food components affecting the oil absorption and crispness of fried batter

Frying batters are used to add value to a product by improving texture, flavour, weight and volume and reducing water loss during frying which, in turn, lessens oil absorption. The physical characteristics of fried batters were studied using model systems based on rice flours. Crispness was positively correlated with amylose content, while oil absorption was negatively correlated with amylose content. Addition of pregelatinised rice flour improved crispness but resulted in increased oil absorption because of the porous nature of the fried product. Amongst the proteins (egg yolk, gluten, skimmed milk, whey and ovalbumin) studied, ovalbumin was able to reduce oil absorption and improve the crispness of the fried batter. Addition of calcium chloride also reduced oil absorption and improved crispness, while a little oil reduced the oil content of the fried batter and improved its taste. Addition of ovalbumin, oil or calcium chloride beyond the optimal levels reduced crispness and increased oil absorption in a linear manner. Modified tapioca starch and diglyceride emulsifiers improved crispness but increased oil absorption. The amount of water added to the formulation affected the physical characteristics of the fried batter. The optimal formulation for a crisp frying batter with reasonably low oil absorption was an amylose/amylopectin ratio of about 18: 67; with (g kg⁻¹) 850 pregelatinised rice flour; up to 150 modified tapioca starch; 30 ovalbumin; 1 calcium chloride; 20 oil; 20 emulsifier and a water/flour ratio of 2:1. © 1998 Society of Chemical Industry.     

Effect of Hydroxypropyl Methylcellulose on Rheological Properties, Coating Pickup, and Oil Content of Rice Flour-Based Batters

Rice flour-based batter is an alternative for wheat flour-based batter for consumers with wheat allergy or wheat intolerance. Further advantage of rice flour in batter is its ability to reduce oil uptake. However, due to its low-protein content, high amylose, and small granule size, rice flour-based batter possesses poor adhesion property. The aim of this study was to investigate the effect of the addition of hydroxypropyl methylcellulose (HPMC); a hydrocolloid, on rheological properties, coating pickup, and oil absorption of HPMC-rice-based fried batter. Rheological properties of rice flour-based batters containing HPMC with different degrees of substitution (DS) and concentrations were determined. In steady-shear measurements, the addition of HPMC; E4M (DS = 1.9) and K4M (DS = 1.4), led to the increase of apparent viscosity, yield stress, and consistency index. K4M rice flour batters showed shear-thickening behavior (n > 1) with syneresis. HPMC increased the complex modulus (G*) of batters, where storage moduli (G′) were higher than loss moduli (G″). The crossover points increased with increasing HPMC concentration. HPMC addition increased the coating pickup of fresh carrot sticks and less coating loss was observed with K4M. Rice batter formulated with 0.5% E4M provided deep-fried crust with 26% lower oil content compared to the control crust.     

Improvement of the quality of gluten‐free sponge cake using different levels and particle sizes of carrot pomace powder

In this study, carrot pomace powder (CPP) with particle sizes of 210 μm (CPP210) and 500 μm (CPP500) was added in the gluten‐free sponge cake recipe. Flour (rice and corn flour, 1:1, w/w) was replaced with 0, 10, 20 and 30% CPP. With increasing the level and particle size of CPP, batter density, viscosity, consistency and firmness increased. The control cake had a dense, hard texture, irregular shape and low sensory scores. These properties improved with addition of CPP so that the cake density, hardness and cohesiveness reduced, while symmetry index and sensory scores increased. Varying the particle size of CPP had no considerable effects on most of the batter and cake properties, while increasing the level of CPP had great positive effects on the quality of batter and cake. Overall, addition of 30% CPP with either of the particle sizes resulted in an acceptable gluten‐free cake.     

Effects of pre-heating temperature and formulation on porosity,moisture content,and fat content of fried batters

The effect of pre-heating temperatures on moisture and fat contents, and porosity of fried batters was studied. Batter pre-heated at 60 °C showed higher moisture content, lower fat content and lower porosity than non-pre-heated batter and batters pre-heated at 70 and 80 °C. Moisture content, fat content, and porosity at 4 min frying for batters with different pre-heating treatments ranged from 35.08 to 39.37, 3.92 to 5.16, and 13.14 to 45.31 %, respectively. Because of significant reduction in fat content, 60 °C pre-heating temperature was chosen to study the effect of batter formulations on moisture and fat contents, and porosity. Different wheat to rice flour ratios were prepared, and then each batter was pre-heated at 60 °C. Batters with higher wheat flour content showed higher moisture content, and lower fat content and porosity than batters with higher rice flour.     

Effect of extrusion conditions on the physicochemical properties of a snack made from purple rice (Hom Nil) and soybean flour blend

Soy flour was added at levels of 5%, 10%, and 15% of Hom Nil rice flour for extrusion at 190 °C barrel temperature and 350 rpm screw speed. The extruded snack qualities decreased inversely with soy flour. However, product qualities were considered to be optimised when soy flour at 5% was added. The effect of feed moisture content (15, 17, 19 g (100 g)^?1 wb), barrel temperature (150, 170, 190 °C) and screw speed (350, 400, 450 rpm) on physicochemical properties of the snack were then investigated. The physicochemical properties of the product including expansion ratio, density, water absorption index (WAI), water solubility index (WSI) and hardness were evaluated. All properties were related, as linear equations, in terms of feed moisture content, barrel temperature, screw speed with relative correlation (R²) at 0.83–0.94. The snack properties along with consumer acceptance were all highest when the extruded condition were 15 g (100 g)^?1 wb feed moisture content, 170 °C of barrel temperature and 450 rpm of screw speed.     

PROPERTIES OF IDLI BATTER DURING ITS FERMENTATION TIME

Idli is a traditional fermented rice and black gram‐based breakfast food of South India. Idli batter was prepared from soaking polished parboiled rice and decorticated black gram for 4 h at 30 ± 1C in water. The soaked mass was ground to 0.5‐ to 0.7‐mm particle size batter using wet grinder with adequate amount of water. The blend ratios of 2:1, 3:1 and 4:1 (v/v) batter were allowed for fermentation (0, 6, 12, 18 and 24 h) adding 2% of salt. The idli batter parameters viz. bulk density, pH, percent total acidity, flow behavior index and consistency coefficient were studied for different fermentation times and blend ratios. The bulk density, pH and percentage total acidity of batter during different fermentation times and blend ratios ranged between 0.94 and 0.59 g/cm³, 5.9 and 4.1 and 0.443 and 0.910%, respectively. The consistency coefficient at any fermentation time shows increasing trend as the rice to black gram ratio increased. The flow behavior index indicated strong non‐Newtonian fluid behavior (pseudoplastic) of idli batter at different fermentation times and blend ratios.     

Porosity determination of deep‐fat‐fried coatings using pycnometer (Fried batter porosity determination by pycnometer)

The effect of processing conditions such as frying time and temperature, and batter formulation on pore development in deep‐fat fried chicken nuggets coatings were studied using helium pycnometer method. Chicken nuggets with preformed and laboratory prepared batter coatings were fried at temperatures between 170 and 190 °C for a time range between 0 and 240 s. There was significant (P < 0.05) effect of frying temperature and batter formulation on porosity. Porosity increased with frying time and temperature, and ranged between 2.15 and 47.92% for the preformed batter and 9.96 and 54.76% for the formulated batters. Apparent and bulk densities of the preformed batters increased and decreased with frying time, respectively, but both declined gradually with increasing frying temperature. As the level of rice flour in the formulation increased, apparent and bulk densities also increased. Batter formulation and frying temperature significantly (P < 0.05) influenced the variation in moisture and fat content of the fried batter. Porosity demonstrated positive and negative correlation with fat uptake and moisture loss, respectively, for all the batter coatings.     

Effects of Rice Batter on Oil Uptake and Sensory Quality of Coated Fried Okra

ABSTRACT: Okra was coated and deep-fat fried with batters of flour sources including rice flour, a mixture of rice flour and small amounts of pregelatinized rice flour (PGRF), and, as a control, traditional wheat flour. The addition of PGRF, up to 8%, enhanced batter viscosity and the coating properties of the rice batter. Oil uptake of the fried batter decreased with the addition of up to 5% PGRF. Rice flour fried batters, with and without PGRF, were found to absorb substantially lower oil, by as much as 51 %, compared with the wheat batter. The fried okra coated with the rice batter containing 5% PGRF, when evaluated for sensory properties on appearance and surface attributes, was found to be superior or equal to those with the wheat batter and rice batter without PGRF. Particularly, its golden brown color is considered more desirable than the lighter yellow color of the other 2 entities. Similarly, most of its 1st-bite and after-chew properties were slightly better and were in the normal range of commercially available products. Specifically, its distinctive crispiness is considered a positive attribute, whereas its slightly higher tooth packing properties, while remaining in the range of commercial products, may be noticeable to some consumers.     

Production of acrylamide in agricultural products by cooking

Some model studies were performed using various agricultural Products, to clarify the relation between cooking conditions and production of acrylamide (AA). Disc chips made from dried mashed potato, corn meal, wheat flour, rice flour (jyohshin-ko) and glutinous rice flour (shiratama-ko), and dried sesame (arai-goma) and dried almond were baked at 120-200 degrees C for 5-20 min, and the samples were analyzed for the levels of AA. When the samples were baked for 10 min, the highest production of AA was observed at 180-200 degrees C. When the samples were baked at 180 degrees C, AA levels in agricultural products except sesame were highest after baking for 10 min. Vegetables and fruit were baked at 220 degrees C for 5 min with a oven, high AA concentrations were found in baked potato, asparagus, pumpkin, eggplant and green gram sprouts. Concentrations of AA in potato, asparagus and green gram sprouts baked after being pre-cooked by microwave irradiation were higher than those in the products baked without being precooked. On the other hand, the precooking by boiling reduced the production of AA by baking to 1/10-1/4. Acrylamide was not found in microwaved or boiled vegetables. High free asparagine concentrations in crops tended to result in high concentrations of AA being produced by heating the agricultural products.     

Effects of particle size distributions of rice flour on the quality of gluten-free rice cupcakes

The particle size distributions (PSD) of rice flour and milling processes are important in making gluten-free products. The dry rice flour was prepared by grinding dried rice grains after soaking. Effects of PSD on the quality of rice cupcakes were investigated using the newly-developed rice flour. The flour properties passed through 80, 120, 160, and 200 (<180, <125, <95, and <75 μm) meshsieves, and batters and cupcakes prepared from their flours were analyzed. The PSD patterns showed two peaks containing cells and free starch fractions, in which the starch fraction peak intensity increased as a particle size decreased. While damaged starch, water binding capacity, solubility and lightness increased, crude protein and yellowness decreased as a particle size decreased. The final and setback viscosities increased as a particle size decreased. The specific volume of cupcakes was the highest in the cupcakes made with rice flour passed through under 95 μm. Hardness and springiness decreased as a particle size decreased. The air cell sizes decreased as a particle size decreased with homogeneity. Air cell homogeneity, volume, hardness, and softness of cakes determined by the different test, and appearance, texture, and overall quality determined by the preference test were all significantly different (p < 0.05).     

Formulation and characterization of hypo allergic weaning foods containing potato and sprouted green gram

Potato flour, green gram flour (sprouted as well as unsprouted), were blended in different proportions with apple pulp (10 %), sugar (10 %), milk and water for formulation of 12 hypo allergic diets. Diets were studied for physico-chemical properties, antinutrient content (phytate and oxalate) and invitro protein digestibility. Blending and sprouting significantly affected all the studied parameters. Sprouting significantly (P ≤ 0.05) improved protein content and invitro protein digestibility while carbohydrate content and antinutrients decreased significantly. Nutrition profile of water-based diets met RDA guidelines only after addition of sprouted green gram flour and were comparable to control (commercial weaning food). Water based formulation showed lower sensory score than milk based diets however; addition of sprouted green gram flour significantly (P ≤ 0.05) improved their overall acceptability. It could be concluded that by incorporating sprouted green gram flour, milk could be replaced with water for production of hypo allergic weaning foods without affecting the nutritional and sensory attributes of formulations and thereby making the production more economical especially for under developed countries.     

Effects of batters containing different gum types on the quality of deep‐fat fried chicken nuggets

The effects of various gum types [hydroxypropylmethylcellulose (HPMC), guar gum, xanthan gum, gum arabic] on the quality of deep‐fat fried chicken nuggets were studied. Chicken samples, 0.04 m in diameter and 0.015 m in thickness taken from the breast portion, were coated with batters composed of a 3:5 solid to water ratio by immersion. The solid content of batter formulations contained equal amounts of corn and wheat flours, 1.0% gum, 1.0% salt and 0.5% leavening agent. As control, batter without gum addition was used. Samples were fried at 180 °C for 3, 6, 9 and 12 min. The hardness and oil content of the chicken nuggets increased whereas the moisture content decreased during frying. HPMC and xanthan gums reduced oil absorption significantly compared with other gums and the control. When gum arabic was added to the batter formulation, a product with the highest oil content and porosity was obtained. Copyright © 2005 Society of Chemical Industry     

Functional Properties of Extruded Rice Flours

The functional properties of a long‐grain and a short‐grain rice flour extruded at 70 to 120°C and 22% moisture are reported. The bulk densities essentially stayed unchanged. Both water absorption and water solubility indices increased with an increase in extrusion temperature. The fat absorption indices decreased only at 55°C. The cold‐paste viscosities progressively increased, whereas the peak, breakdown, setback, and final viscosities decreased with an increase in extrusion temperature. A substitution of 25% of unextruded or 70°C extruded long‐grain rice flour into a wheat flour‐based fried snack decreased its fat absorption by 35% to 50% without affecting the overall texture.     

Oil Absorption and Sensory Properties of a Snack Food from Chickpea Genotypes

Among the commonly consumed grain legumes the score on general acceptability of a snack food (seviya) was the highest for that from chickpea (Cicer arietinum L.) followed by lentil, pigeonpea and green gram, whereas the oil absorption by the product was highest for lentil followed by black gram, chickpea, and green gram. Different methods of dehulling did not cause any notable effects on oil absorption of chickpea seviya. The flour particle size, starch, and protein contents significantly influenced oil absorption of seviya. The oil absorption of the product differed significantly among genotypes, but clear cut differences were not found between desi and kabuli groups of chickpea genotypes.     

Okara flours from chickpea and soy are thickeners: increased dough viscosity and moisture content in gluten-free bread

The by-product of plant-based beverages, okara, can be dried in a nutritious flour, but it generates dense bakery products due to high water absorption. Gluten-free bread often tastes dry, so the objective of this work was evaluating okara flour as thickener for mouthfeel enhancement. Proximate analysis revealed that chickpea okara contained more starch than soy (35.3 vs. 3.41 g/100 g), less insoluble fibre (43.3 vs. 57.0 g/100 g) and protein (9.51 vs. 18.1 g/100 g). Water absorption capacity was higher in okara than flour and for soy (8.29 vs. 6.01 g g⁻¹, respectively). When added to a gluten-free batter, both okara flours significantly increased viscosity. Upon addition of either okara to gluten-free bread (2% w/w) moisture content increased from 31.6 to 33.5 and 36.5 g/100 g, while crumb hardness increased by up to 45% and specific loaf volume decreased by up to 42%. Soy okara flour enhanced moistness of gluten-free bread.