Optimization of Quality Properties of Gluten-Free Bread by a Mixture Design of Xanthan, Guar, and Hydroxypropyl Methyl Cellulose Gums
The objective of this study was to investigate, by means of a D-optimal mixture design, the combined effects of hydroxypropyl methyl cellulose (HPMC), xanthan (XG), and guar (GG) gums on physicochemical, rheological, and textural properties of gluten-free batter and bread. For each of the quality properties measured, a two-factor interaction model was fitted, and the significance of its terms was assessed by analysis of variance. Sticky batters were produced with a combination of high dose of GG (0.60%), high-intermediate dose of HPMC (3.36%), and low dose of XG (0.04%). Combinations of high XG dose (0.60%) and intermediate doses of HPMC (3.08%) and GG (0.32%) rendered GF breads of greater specific volume, while lower bread crust luminosity was obtained with combinations of high GG dose (0.60%), low XG dose (0.04%), and high-intermediate HPMC dose (3.36%). Combinations of high-intermediate HPMC dose (3.36%), high GG dose (0.60%), and low XG dose (0.04%) produced both softer crumbs and bread slices of more open visual texture. By using a desirability function that maximized specific volume while minimizing crust luminosity, crumb hardness, and mean cell density, the optimization of hydrocolloids mixture rendered a value of 0.54, for a combination of 0.24% XG, 0.60% GG, and 3.16% HPMC.
Optimization of rheological properties of gluten-free pasta dough using mixture design
Abstract The rising demand of gluten-free products for celiac people has led to important technological research on the replacement of the gluten matrix in the production of high quality gluten-free foods. The objective of this work was to evaluate the effect of composition (hydrocolloids, water, and proteins) on the rheological and textural properties of gluten-free dough used for producing pasta based on corn-starch and corn flour. Extensibility and rheological properties of gluten-free pasta dough were studied. Rising protein or gum contents produced a marked increase of deformation at break. However protein content was negatively correlated with breaking force. The increase in gums content produced an increase in storage and loss moduli (G′, G″). G′ was always larger than G″ with a small increase of both moduli with frequency. The mechanical relaxation spectrum was predicted from dynamic oscillatory data using the broadened Baumgaertel–Schausberger–Winter model. Application of a mixture design allowed finding the optimal composition to achieve the desirable textural properties using response surface methodology. A formulation containing 35.5% water, 2.5% gums, 4.7% proteins, 42.8% corn-starch, 10.7% corn flour, 1% NaCl, and 2.8% sunflower oil led to the highest values of G′, breaking force, and extensibility according to the optimization analysis performed.
Labeling and regulatory issues
Publisher Summary Studies have shown that 1 in 100 people worldwide have celiac disease, making it one of the most common food intolerances. The only treatment for celiac disease is the total avoidance of gluten from wheat and the related proteins from barley, rye, oats, or any Triticum species or their crossbred varieties. The total exclusion of gluten-containing foods and ingredients in foodstuffs is very important to avoid health hazards, this was extremely difficult to realize in the past because of inadequate labeling directives regarding, (a) compound ingredients, (b) class names, and (c) the usage of wheat gluten for technological reasons. Improvement in the worldwide Codex Standard on Food Labeling and national food labeling legislations has resolved the health hazard posed by unknown gluten intake. It is caused by insufficient declaration of gluten-containing ingredients and food additives in foodstuffs. The labeling exemption of derivatives, in which the gluten content has been removed, contributes to a better understanding when reading the label of the food, whether or not gluten-containing ingredients and additives have been used. Efforts are made to exclude contamination by adequately cleaning of shared processing equipment in foods prepared for normal consumption. The improvement of several Codex Standards and Guidelines has contributed to the safety and large variety of gluten-free foods and, as a consequence, guarantee a better quality of life for the gluten-intolerant population.