Flour Tortillas Research Articles

Fortification of All-Purpose Wheat-Flour Tortillas with Calcium Lactate, Calcium Carbonate, or Calcium Citrate Is Acceptable

Fortification helps provide adequate nutrients for individuals not meeting daily needs. Foods may be fortified with calcium to assist individuals with lactose intolerance and others preferring not to consume traditional forms of dairy. This study examined the quality of all-purpose wheat-flour tortillas fortified with calcium lactate, calcium carbonate, or calcium citrate. These tortillas were compared to similarly prepared nonfortified flour tortillas (control) and commercial nonfortified flour tortillas. Calcium-fortified tortillas contained 114 mg elemental calcium per standard serving (48 g tortilla), an 8.6-fold increase compared to nonfortified tortillas. Moisture contents and rollabilities of all tortillas were similar. Consumers (N=87) evaluated each tortilla in duplicate using a hedonic scale and reported liking the appearance, texture, flavor, aftertaste, and overall acceptability of all tortillas. However, the appearance of control tortillas was preferred over commercial tortillas ( P<0.01), whereas the aftertaste of commercial tortillas or those fortified with calcium carbonate was preferred over the control ( P<0.05). Despite these differences, consumers were equally willing to purchase both fortified and nonfortified tortillas, suggesting that appearance and aftertaste may not influence willingness to purchase. Overall, this study shows that fortification of flour tortillas with various forms of calcium is a feasible alternative calcium source.

Effect of Emulsifiers on Textural Properties of Whole Wheat Tortillas During Storage

Flour tortillas are one of the most popular and successful products in the baking industry (Hillebrand 2005). Texture and organoleptic characteristics of tortillas are major criteria that consumers use to judge the overall quality. Good quality tortillas should stay flexible and rollable without cracking and breaking when folded, and be soft without sticking together (Wang and Flores 1999). One of the major problems in tortilla quality is the deterioration of texture with time due to staling (Waniska 1999). Shelf life of tortillas can be improved through ingredients and formulation. Emulsifiers, a subset of surfactants, may impart antistaling characteristics aside from their emulsifying action (Stampfli and Nersten 1995; Seyhun et al 2003) and have been widely used by the baking industry. Sodium stearoyl lactylate (SSL), an anionic surfactant, is primarily used as a dough strengthener and a crumb softener in the baking industry. It is believed that SSL interacts with gluten during mixing, resulting in improved dough strength, and then forms a complex with amylose and amylopectin during baking. This results in crumb softening by retarding the starch staling process (DeStefanis 1977; Bernardin 1978). The strong association between SSL and gluten at the dough stage has been suggested to delay denaturation and setting of gluten during baking (Stauffer 1999). After baking, most of the SSL interacts hydrophobically with starch, which is thought to reduce the rate and extent of staling (Chung 1986). Glyceryl monostearate (GMS) is a derivative from α-monoglycerides and is known to improve texture. Similar to SSL, GMS has the ability to form complexes with amylose, hence, inhibiting the firming of baked goods due to staling (Krog and Nybu-Jensen 1970). The N-alkyl portion of GMS forms a complex with the helical regions of amylose, a phenomenon that is thought to be responsible for its effect in retarding starch crystallization, slowing the staling process. The interaction between GMS and amylose takes place at the surface of the granules, and the amylose-emulsion complex serves to stabilize the granule, retarding water penetration and swelling as the temperature is raised (Stauffer 1999). Soybean lecithin, an amphoteric surfactant, is a natural emulsifier and a mixture of phosphatides. Lecithin, unlike SSL and GMS, does not form a complex with the starch; (Stampfli and Nersten 1995). Instead, it interacts with flour gluten in baked products to extend shelf life. Lecithin is classified as a GRAS substance with a long history of safe food applications (McCormick 1986). According to dietary guidelines for Americans published by the USDA, 100 g of enriched, bleached, all-purpose white flour contains only 2.7 g of dietary fiber, whereas 100% whole wheat (WW) flour has 12.2 g of fiber/100 g of flour. Even though the importance of dietary fiber has been stressed by health organizations, including USDA, the average intake of dietary fiber of Americans is less than the recommended average by the National Cancer Institute (Hopkins Technology, LLC). Therefore, there is a noteworthy health benefit for consuming 100% WW products. Moreover, 100% WW products are rich in B and E vitamins, iron, phytochemicals, and phytoestrogens. Published research on 100% WW tortillas is scarce. Thus, the purpose of this study was to investigate the effects of three selected emulsifiers on both the objective and subjective textural properties of tortillas made from 100% WW flour.

Multiple Outbreaks of Gastrointestinal Illness Among School Children Associated with Consumption of Flour Tortillas—Massachusetts, 2003-2004

Multiple Outbreaks of Gastrointestinal Illness Among School Children Associated with Consumption of Flour Tortillas—Massachusetts, 2003-2004

Effect of nutritionally fortified tortillas on growth and physical development in the pig

The physical development of muscle, bone, and blood in pigs fed diets containing different forms of tortillas was evaluated. The tortilla products included corn tortillas (TN), TN with a mixture of 0.15% vitamins and minerals (TNV), TN with 4% (as is) defatted soy paste (TNS), corn flour tortillas (TH), TH with vitamins (THV), and TH with soy paste (THS). The femur weight of pigs fed the TNS and THS diets was higher ( P > .05) than those of pigs fed TN, TNV, TH, and THV diets. Calcium in femurs was lower for the TN and TH diets compared with TNV, THV, TNS, and THS diets. Blood analysis showed that the hematocrit, hemoglobin, and erythrocytes values were optimal in pigs fed TNS and THS. Tortilla fortification with soy may have important nutritional benefits based on the evaluation in the pig growth and development model.

Rheological and Sensory Evaluation of Wheat Flour Tortillas During Storage

ABSTRACTTexture of wheat flour tortillas over 15 days at room temperature was evaluated using an expert sensory panel, consumer panels, subjective rollability test, large deformation rheological methods (i.e., bending, extensibility [1‐D and 2‐D], and puncture tests), and stress relaxation method. Most of the changes in texture occurred during the initial 8 days of storage, while texture of tortillas changed slowly thereafter. Differences in texture between fresh and 1‐day‐old tortillas were detected by many objective rheological methods but not by either sensory panel. The expert sensory panel observed a rapid decrease in tortilla extensibility and an increase in staleness between 1 and 8 days of storage and smaller changes in sensory scores after 8 days of storage. Most objective rheological parameters changed rapidly between 0 and 5 days, and slowly after 5 days of storage. Significant correlations and factor analysis reveal that changes occurring in flour tortillas during staling are estimated better by subjective rollability, sensory evaluation (expert and consumer panels), and 2‐dimensional extensibility test than by other methods. Hence, some rheological methods are useful to estimate sensory properties of flour tortillas.

Elimination of Listeria monocytogenes from Ready-to-Eat Turkey and Cheese Tortilla Wraps Using Ionizing Radiation

Listeria monocytogenes is a common postprocess contaminant on ready-to-eat foods including premade ready-to-eat sandwiches. One popular type of sandwich product is the tortilla wrap, which contains sliced luncheon meats and cheeses rolled within a flour tortilla. This study determined the radiation resistance of L. monocytogenes surface inoculated onto two types of commercially available wheat flour tortillas, processed cheese slices, and deli turkey meat. The D10-values for L. monocytogenes (the radiation dose required to inactivate 1 log of the pathogen) were 0.27 kGy when inoculated onto two flour tortilla types, 0.28 and 0.30 kGy when inoculated onto two types of sliced processed cheeses, and 0.58 and 0.65 kGy when inoculated onto two types of sliced deli turkey meat. When two types of tortilla wraps were assembled from the individual components and L. monocytogenes was inoculated into the interfaces between the individual components, the D10-values were 0.27 to 0.37 kGy in the tortilla and cheese interfaces, 0.33 to 0.41 kGy in the cheese and turkey interfaces, and 0.25 to 0.33 kGy in the turkey and tortilla interfaces. The ability of ionizing radiation to reduce pathogen levels on the complex tortilla, cheese, and luncheon meat product was limited by the higher radiation resistance of L. monocytogenes when inoculated onto the ready-to-eat turkey-meat component.

A Preliminary Evaluation of the Effect of Glove Use by Food Handlers in Fast Food Restaurants

A study was conducted to determine whether the levels of selected microorganisms differed on foods handled by gloved and bare hands at fast food restaurants. Three hundred seventy-one plain flour tortillas were purchased from fast food restaurants and analyzed for Staphylococcus aureus, Escherichia coli, Klebsiella sp., coliform bacteria, and heterotrophic plate count bacteria. Approximately 46% of the samples were handled by workers wearing gloves compared with 52% of samples with bare hand contact. Coliform bacteria were found in 9.6% of samples handled by gloved workers and 4.4% of samples handled by bare hands, although this difference was not statistically significant. The distribution of heterotrophic plate count bacteria, a general measure of hygiene, was also higher in samples handled by gloved workers in one restaurant chain. The presence of E. coli, Klebsiella sp., and S. aureus was detected in one, two, and eight samples, respectively, and there were no significant differences between samples handled by gloved or bare hands. Neither direct contact of the tortilla with the food preparation surface nor gender of the worker affected the level of any organism tested. The observed tendency of food workers to wear the same pair of gloves for extended periods and complacency might account for the apparent failure of gloves to reduce or prevent bacterial contamination. The results further suggest that glove use might be counterproductive because workers might wash their hands less frequently when gloved.

Calcium-fortified flour tortillas: evaluation of physical and sensory properties

Calcium-fortified flour tortillas: evaluation of physical and sensory properties

Potential of Triticale as a Substitute for Wheat in Flour Tortilla Production

ABSTRACTThe potential of triticale as a partial or total substitute for wheat in flour tortilla production was evaluated. Different mixtures of triticale and wheat flours were tested in a typical hot‐press formulation. Both grains yielded similar amounts of flour. Wheat flour contained 1.5% more crude protein, 1.6× more gluten, and produced stronger dough than triticale. Triticale flour significantly reduced optimum water absorption and mix time of blends. Flour tortillas with 100% triticale absorbed 8% less water and required 25% of the mix time of the control wheat flour tortilla. The yield of triticale tortillas was lower than the rest of the tortillas due to lower moisture content and water absorption. Triticale dough balls required less proofing and ruptured during hot pressing, thus producing defective tortillas. The 50:50 flour mixture produced doughs with acceptable rheological properties and good quality tortillas. Addition of 1% vital gluten to the 75:25 triticale‐wheat flour mix or 2% to the 100% triticale flour significantly increased water absorption and mix time and improved dough properties and tortilla yields. Textural studies indicated that increasing levels of triticale flour reduced the force required to rupture tortillas. For all tortilla systems, rupture force gradually increased, and extensibility decreased during seven days of storage at room temperature; the highest rate of change occurred during the first day. Sensory evaluation tests indicated that triticale could substitute for 50% of wheat flour without affecting texture, color, flavor, and overall acceptability of tortillas. For production of 100% triticale flour tortillas, at least 2% vital gluten had to be added to the formulation.

The Poor Bioavailability of Elemental Iron in Corn Masa Flour Is Not Affected by Disodium EDTA

The most sustainable way to eradicate iron deficiency is through food fortification. Elemental iron powders are commonly utilized as fortificants due to their low cost and few sensory problems. However, their bioavailability is unknown. Our goals were to measure the bioavailability of elemental iron in Mexican style corn masa flour tortillas and to evaluate the effects of Na(2)EDTA. We used a stable isotope of H(2)-reduced iron powder, with and without Na(2)EDTA in tortillas prepared with corn masa flour. Two groups of 5- to 7-y-old children (n = 12/group) were fed tortillas to which was added 3 mg/100 g of H(2)-reduced (58)Fe with a mean particle size of 15 micro m. In one group, Na(2)EDTA was incorporated at a ratio of 1:2 mol/mol. The next day, (57)Fe ascorbate was given as a reference dose. After 14 d, blood samples were analyzed for isotopic enrichment. When normalized to 40% absorption of the reference dose, the geometric mean (+/-range 1 SD) bioavailability of reduced iron in tortilla was 3.8% (2.7-5.3). The addition of Na(2)EDTA, tended to increase it (P = 0.18) to 5.1% (2.8-9.2). This observed low absorption was compounded by the use of iron isotopes with smaller particle size (mean diameter 15 micro m) than typical of commercial elemental iron powder (<45 micro m). We conclude that H(2)-reduced iron powder is an ineffective fortificant in corn tortillas.

Effects of Wheat Protein Fractions on Flour Tortilla Quality

ABSTRACTCommercial wheat protein fractions (10) were evaluated during processing for quality of tortillas prepared using pastry, tortilla, and bread flours. Protein fractions that separately modify dough resistance and extensibility were evaluated in tortillas to determine whether the proteins could increase diameter, opacity, and shelf stability. Tortillas were prepared using laboratory‐scale, commercial equipment with fixed processing parameters. Dough and tortilla properties were evaluated using analytical methods, a texture analyzer, and subjective methods. Tortillas were stored in plastic bags at 22°C for up to 20 days. Adjustments in water absorption and level of reducing agent were made to normalize differences in functionality of 3% added proteins on dough properties. Tortilla weight, moisture, pH, opacity, and specific volume were not affected by added proteins, except for glutenin and vital wheat gluten treatments, which had decreased opacity in tortillas prepared from pastry flour. Increased insoluble polymeric protein content corresponded to decreased tortilla diameter and improved shelf stability. Treatments yielding tortillas with improved shelf stability and similar tortilla properties were produced when commercially processed vital wheat gluten products, FP600, FP6000, FP5000, or gliadin were added to pastry or tortilla flour. These wheat protein fractions improved processing and tortilla quality of wheat flours, especially pastry flour, by modifying protein content and quality.

In vitro starch digestibility changes during storage of maize flour tortillas.

Nixtamalized maize flours elaborated by four factories in Mexico were used for tortilla preparation. Samples were stored at 4 degrees C for up to 72 h and their in vitro starch digestibility features were evaluated. Moisture content was different between flour and tortilla but no evident relation could be established. Protein and lipid levels were lower in tortillas than in flour but ash content was not different in both samples. A decrease in available starch content was observed upon 48 h cold storage (4 degrees C), changes that were concomitant with increased total resistant starch (RS) levels. These changes were due mainly to retrogradation, as suggested by the increased retrograded resistant starch (RRS) levels recorded in stored tortillas; in some samples, RRS represented up to 100% of total RS. The digestion (alpha-amylolysis) rate (DR) of freshly prepared tortillas differed for the various samples. Although the amylolysis patterns for fresh and 72 h-stored tortillas were similar, lower DR values were shown for the stored materials. The differences found among the various tortilla samples may be due to variations in processing conditions during commercial maize flour preparation, and to the use of different maize varieties.

The Effects of Storage Temperature on the Staling of Wheat Flour Tortillas

Abstract Wheat flour tortillas (31·9% moisture) were stored at −60, −12, 0, 4, 22, and 35 °C to evaluate textural changes during staling. Subjective rollability and two-dimensional extensibility tests revealed that tortillas stored at ≥0 °C had increasing force, work and modulus of deformation values during storage. Tortillas stored at ≤−12 °C retained their fresh attributes over 25 days. Tortillas staled more as defined by rheological changes when stored at 22 °C than at 0, 4, or 35 °C. Optimum storage temperatures of wheat flour tortillas are ≤−12 °C while optimum staling temperatures are between 4 and 35 °C.

Objective Texture Measurements of Commercial Wheat Flour Tortillas

ABSTRACTTexture is a property of major importance in the evaluation of baked products. To determine a sample of commercial ranges for stretchability, rollability, firmness, and Kramer shear cell measurements for wheat flour tortillas using the TA‐XT2 texture analyzer, three separate sets of five tortilla brands purchased from stores in Manhattan, KS, were evaluated. Two brands had two formulations, regular and fat‐free. Significant differences (P &lt; 0.05) in stretchability, firmness, and Kramer shear cell occurred between regular and fat‐free tortillas of one tortilla brand. Significant differences (P &lt; 0.05) also were found among the sets of some tortilla brands. Kramer shear cell and stretchability measurements are recommended because Kramer shear cell measures the force combined with compression, shearing, and extrusion. Stretchability measurements were repeatable and are an important textural property of wheat flour tortillas. Ranges for textural properties for commercial wheat flour tortillas were determined, as well as the variability of the textural methods used.

Effect of Partial Waxy Wheat on Processing and Quality of Wheat Flour Tortillas

ABSTRACTThe processing and quality of wheat flour tortillas prepared with partial waxy and normal flour were evaluated. Control procedures and formula were utilized with water absorption varied to obtain machineable doughs. Amylose content was lower in most partial waxy compared with normal wheats. The type of wheat starch did not affect most dough properties or tortilla diameter. Tortilla height and opacity were adversely affected by the decreased amount of amylose in partial waxy wheats. Sufficient leavening reactions occurred early in baking (after 10 sec) to yield an opaque disk, but some baked tortillas lost opacity and become partially transparent after baking. Starch gelatinizes, disperses, and retrogrades concurrently with the leavening reaction during the short (&lt;30 sec) baking time. Amylose functionality during baking and cooling appears to be involved in the retention of air bubbles in tortillas.

Characteristics of maize flour tortilla supplemented with ground Tenebrio molitor larvae.

The larva of the Tenebrio molitor, known as the yellow meal worm, is a plague of wheat and flours. Consumption of the raw insects is not well accepted because of their appearance. The objective of the present work was to grow T. molitor larvae under standard conditions, to analyze the chemical composition of the larvae powder, and to prepare supplemented maize tortillas. Protein and fat contents were performed with standard methods. Tenebrio larvae powder had a 58.4% protein content; this protein was rich in essential amino acids such as phenylalanine, tyrosine, and tryptophan; the found values satisfied those recommended by the Food and Agriculture Organization. Fatty acid composition was determined by GC-MS showing high contents of oleic acid and linoleic acid (19.8 and 8.51%, respectively). A large proportion of unsaturated fatty acids of longer chains was detected. Long-chain fatty acids having two or three double bonds have been claimed as highly beneficial to health. Tortillas supplemented with larvae powder had excellent consumer acceptance, and tortilla protein content increased by 2% as well as the amount of essential amino acids. These results show new ways to consume insects and at the same time increase the nutritional value of the original food products.

Mechanical Starch Damage Effects on Wheat Flour Tortilla Texture

ABSTRACTTo investigate the effects of mechanically damaged starch and flour particle size on the texture of fresh and stored flour tortillas, two commercial hard red winter wheat flour samples were reground four times using decreasing roll gaps. Tortillas were made with a modified hot‐press procedure. Texture characteristics were measured after tortillas were stored 2 hr (fresh tortilla), 2 days, and 4 days. Damaged starch and particle size significantly affected (P &lt; 0.05) flour water absorption, dough extensibility and resistance, and dough viscosity. As damaged starch increased and particle size decreased, the flour tortillas became less stretchable, the maximum force of Kramer shear decreased, and firmness and rollability increased. The effects of damaged starch and particle size on stretchability and Kramer shear were greater in fresh tortillas than in stored tortillas and became smaller as the storage time increased. However, the effects of damaged starch and particle size on rollability and firmness were smaller in fresh tortillas than in stored tortillas but became greater as the storage time increased.

Effects of Leavening Acids and Dough Temperature in Wheat Flour Tortillas

ABSTRACTFunctionality of four leavening acids (sodium aluminum phosphate [SALP], sodium aluminum sulfate [SAS], monocalcium phosphate [MCP] and sodium acid pyrophosphate [SAPP‐28]) was evaluated during processing of wheat flour tortillas. Formulas were optimized to yield opaque, large‐diameter tortillas with pH 5.9–6.1. Each leavening acid and sodium bicarbonate was first evaluated at 38°C and then evaluated in combination with fumaric acid at 34 and 38°C. Ionic and pH interactions of leavening salts adversely affected dough properties and resting time. Opacity and pH of tortillas prepared with MCP was lower than for other treatments. Higher dough temperature required more leavening acid and base to compensate for some of the loss of CO2 incurred during dough mixing and resting at 38°C. The addition of fumaric acid decreased the amount of leavening acid, the dough‐resting time and tortilla pH, and improved storage stability. Combinations of MCP, SALP (or SAS), and fumaric acid produced dough and tortillas with good qualities. Tortillas prepared using SALP (or SAS) and fumaric acid tended to be of better quality.

Effects of Flour Particle Size on the Textural Properties of Flour Tortillas

Three wheat flours, hard red winter (HRW), hard white winter (HWW) and soft red winter (SRW), were fractionated by sieving into four different particle size fractions, <38, 38–53, 53–75, and >75 μm. The medium fractions, 38–53 and 53–75 μm, of the HRW and HWW wheat had higher protein contents than the finest and coarsest fractions. The finest fractions had the highest levels of damaged starch. Tortillas made from the medium fractions of HRW and HWW, especially the 53–75 μm fraction, had longer rupture distance and better foldability. The finest fraction yielded tortillas with shorter rupture distance and worse foldability. Fractionation by flour particle size slightly affected protein composition of the flour. Size exclusion-high performance liquid chromatography (SE-HPLC) analyses showed that the compositions of SRW wheat proteins were significantly different from those of HRW and HWW wheat proteins. SRW had more low molecular weight (LMW) and less high molecular weight (HMW) protein than HRW and HWW had. The <38 μm fractions of HRW and HWW had more LMW proteins than other fractions. The amount of LMW proteins of flours correlated negatively with the rupture distance and foldability of tortillas. Particle size of the flours was the major factor affecting the tortilla texture.

Functionality of Rice and Sorghum Flours in Baked Tortilla and Corn Chips

ABSTRACTThe effects of raw and gelatinized sorghum and rice flours on the structure and texture of baked corn and tortilla chips were evaluated. Dry masa flour was hydrated into masa, sheeted, and cut. Corn chips were baked in an air‐impingement oven, and tortilla chips were baked first in a three‐tier oven and then in an air‐impingement oven. Baked tortilla chips required significantly greater force to break and were less susceptible to breakage during handling than baked corn chips. Raw and gelatinized, normal and waxy rice and sorghum flours significantly changed the texture and structure of baked chips. Waxy rice and sorghum flours reduced peak force and work, increased chip thickness, and improved overall acceptability (as assessed by a taste panel), but waxy rice and sorghum chips were more fragile and had a greater number of large central air cells. Waxy rice was more beneficial than waxy sorghum flour. Gelatinization of waxy flours increased thickness of baked chips, whereas gelatinization of nonwaxy flours had no improvement over waxy flours alone. Gelatinization of sorghum flour significantly decreased the peak force and work values for baked tortilla chips when compared with the control chips. Gelatinized rice flour tortilla chips were not significantly different than the control chips but were significantly harder than the other baked tortilla chips. The complex interactions that occur in baked corn and baked tortilla chips suggest that each ingredient acts differently in the two products. Thus, each ingredient must be evaluated for specific products and processes.