Perla Osorio-Díaz

Effect of Storage Time on In Vitro Digestibility and Resistant Starch Content of Nixtamal, Masa, and Tortilla

ABSTRACT Nixtamal, masa, and tortilla samples were stored for 24–96 hr and their chemical composition, retrogradation, and in vitro starch digestibility features were evaluated. Ash and fat contents in the three products were smaller than in the original corn sample, but protein levels were higher, all in accordance with previous studies. In general, a minor decrease in available starch (AS) content was observed with storage time. Masa showed the greatest AS values, followed by tortilla and nixtamal. Tortilla presented slightly higher retrograded resistant starch (RS3) values (1.1–1.8%, dmb) than masa (0.7–0.9%) and nixtamal (0.7–0.8%) and only minor increases were observed after 24 hr of storage, suggesting that retrogradation phenomenon in these samples takes place very rapidly and is more pronounced in the final product (tortilla). The development of RS3 explains the observed decrease in AS. Higher total resistant starch values were found in all samples at a range of 2.1–2.6% for nixtamal and masa, and...

Physicochemical and Digestibility Properties of Double-Modified Banana (Musa paradisiaca L.) Starches

Banana starch was chemically modified using single (esterification or cross-linking) and dual modification (esterification-cross-linking and cross-linking-esterification), with the objective to increase the slowly digestible starch (SDS) and resistant starch (RS) concentrations. Physicochemical properties and in vitro digestibility were analyzed. The degree of substitution of the esterified samples ranged from 0.006 to 0.020. The X-ray diffraction pattern of the modified samples did not show change; however, an increase in crystallinity level was determined (from 23.79 to 32.76%). The ungelatinized samples had low rapidly digestible starch (RDS) (4.23-9.19%), whereas the modified starches showed an increase in SDS (from 10.79 to 16.79%) and had high RS content (74.07-85.07%). In the cooked samples, the esterified starch increased the SDS content (21.32%), followed by cross-linked starch (15.13%). Dual modified starch (cross-linked-esterified) had the lowest SDS content, but the highest RS amount. The esterified and cross-linked-esterified samples had higher peak viscosity than cross-linked and esterified-cross-linked. This characteristic is due to the fact that in dual modification, the groups introduced in the first modification are replaced by the functional group of the second modification. Temperature and enthalpy of gelatinization decreased in modified starches (from 75.37 to 74.02 °C and from 10.42 to 8.68 J/g, respectively), compared with their unmodified starch (76.15 °C and 11.05 J/g). Cross-linked-esterified starch showed the lowest enthalpy of gelatinization (8.68 J/g). Retrogradation temperature decreased in modified starches compared with unmodified (59.04-57.47 °C), but no significant differences were found among the modified samples.

Development and Characterization of Spaghetti with High Resistant Starch Content Supplemented with Banana Starch

Spaghetti developed by substituting semolina with 5, 10, 15, and 20% (w/w) banana starch were evaluated by specific physical and chemical parameters such as chemical composition, resistant starch (RS) content, diameter, bulk density, color, cooked weight, cooking loss, and firmness. They were also evaluated by their sensory attributes. In general, the addition of banana starch promoted a dilution effect on protein, lipid, and ash content, while moisture content was not affected. On the other hand, the content of RS significantly increased ( p50.05) with an increase of banana starch in the spaghetti. Spaghetti containing 5 and 10% of banana starch had similar diameter than the control spaghetti, but the diameter of spaghetti with 15 and 20% banana starch were significantly lower ( p50.05). The bulk density values of spaghetti with banana starch were all similar and not different from the control spaghetti. The values of ΔL* indicated that the color of spaghetti containing banana starch was darker than the control at all levels of substitution, while the values of ΔC* indicated that only spaghetti containing banana starch in the range of 10—20% was less saturated than the control. The evaluation of cooking quality demonstrated that the cooked weight of spaghetti containing banana starch was similar to the control, but their cooking loss was significantly higher and their firmness significantly lower ( p50.05) than the control. However, the values of cooking loss and firmness were in the acceptable range for good quality pasta. Sensory evaluation of the product showed that the addition of banana starch improved the acceptability of the spaghetti. The overall result of this study shows that spaghetti with up to 15% of banana starch addition could have great potential for commercial acceptability as a functional food with high levels of healthy RS.

Fiber Concentrate from Orange (Citrus sinensis L.) Bagase: Characterization and Application as Bakery Product Ingredient

Orange is a tropical fruit used in the juice industry, yielding important quantities of by products. The objective of this work was to obtain a dietary fiber-rich orange bagasse product (DFROBP), evaluate its chemical composition and its use in the preparation of a bakery product (muffin). Muffins containing two different levels of DFROBP were studied regarding chemical composition, in vitro starch digestibility, predicted glyceamic index and acceptability in a sensory test. DFROBP showed low fat and high dietary fiber contents. The soluble and insoluble dietary fiber fractions were balanced, which is of importance for the health beneficial effects of fiber sources. DFROBP-containing muffins showed the same rapidly digestible starch content as the reference muffin, whilst the slowly digestible starch level increased with the addition of DFROBP. However, the resistant starch content decreased when DFROBP increased in the muffin. The addition of DFROBP to muffin decreased the predicted glyceamic index, but no difference was found between the muffins prepared with the two DFROBP levels. The sensory score did not show difference between control muffin and that added with 10% of DFROBP. The addition of DFROBP to bakery products can be an alternative for people requiring low glyceamic response.

In vitro fermentability and antioxidant capacity of the indigestible fraction of cooked black beans (Phaseolus vulgaris L.), lentils (Lens culinaris L.) and chickpeas (Cicer arietinum L.).

BACKGROUND Pulses represent an important source of protein, as well as digestible and indigestible carbohydrates. Little information is available on the indigestible carbohydrates and antioxidant capacity of legume seeds. The cooked seeds of three pulses (black bean, chickpea and lentil) were evaluated for their indigestible fraction (IF), polyphenols content, antioxidant capacity and in vitro fermentability, including short-chain fatty acid production. RESULTS The insoluble indigestible fraction (IIF) was higher than the soluble counterpart (soluble indigestible fraction, SIF). The SIF value was highest in black beans, while no difference was observed between chickpeas and lentils. Black beans and lentils had higher polyphenols content than chickpeas. The IF of black beans exhibited the lowest and chickpeas the highest associated polyphenols content. Condensed tannins were retained to some extent in the IF that exhibited significant antioxidant capacity. The total IF of the three pulses produced short chain fatty acids (SCFA) after 24 h of in vitro fermentation by human colonic microflora. IF from black bean and lentil were best substrates for the fermentative production of butyric acid. CONCLUSIONS It is concluded that the IF of pulses might be an important source of bioactive compounds.

Effect of the cooking on physicochemical and starch digestibility properties of two varieties of common bean (Phaseolus vulgaris L.) grown under different water regimes

Growing and cooking conditions influence the quality and nutritional value of beans. The objective of this research was to determine the effect of cooking on digestibility and physicochemical properties of two varieties of bean grown under different water regimes. Black 8025 and Pinto Durango varieties were grown in irrigated and temporal (rain fed) conditions in two locations of Guanajuato, Mexico. The pasting profiles of the cooked beans showed a significant decrease in viscosity. The enthalpy of the raw and cooked beans ranged from 2.75 to 3.95 and 0.62 to 0.97J/g, respectively. The percentage of rapidly digestible starch and slowly digestible starch increased, while the percentage of resistant starch was lower in cooked samples. Black 8025 beans had lower glycemic index than Pinto Durango, but no significant difference (P<0.05) was noted between water regimes. The variety of bean had a more pronounced effect on digestibility properties than the water regime.

In vitro digestibility and resistant starch content of some industrialized commercial beans (Phaseolus vulgaris L.)

Commercial bean products were studied in terms of chemical composition and starch digestibility. In general, commercial cooked flours did not show differences in protein and ash contents. Canned beans also did not show statistical differences (α=0.05) in protein, but they were different in ash, perhaps due to botanical variety. Lipid content varied in the different flours, due to the formulation used in their preparation, whereas the canned bean samples had similar lipid values. Canned samples had the highest available starch (AS) values. These results suggest that the drying of samples decreases AS. Canned beans had the lowest total resistant starch (RS) values, and the flours obtained from canned seeds had the highest. These results agree with AS content in the samples. Retrograded resistant starch (RS type 3) showed the same pattern as RS (type 2+type 3), but with lower absolute values. The in vitro α-amylolysis rate for canned beans and commercial flours was lower than for samples dried in the laboratory. Thus, the additional drying step increased the hydrolysis rate of the samples. Therefore, depending on the specific dietetic use of beans, appropriate processing methods and formulations are needed.

Chemical composition, carbohydrate digestibility, and antioxidant capacity of cooked black bean, chickpea, and lentil Mexican varieties Composición química, digestibilidad de carbohidratos, y capacidad antioxidante de variedades mexicanas cocidas de frijol negro, garbanzo, y lenteja

The consumption of legume seeds in developing countries is very important because of their low cost and valuable nutritional characteristics (high protein, digestible and indigestible carbohydrates, and polyphenols content). However, limited information is available on the indigestible carbohydrates and the antioxidant capacity of legumes growing in Mexico. The cooked seeds of three Mexican pulses (black bean, chickpea, and lentil) were evaluated regarding their chemical composition, in vitro starch digestibility, polyphenols content and antioxidant capacity. The highest protein contents were recorded in chickpeas and lentils with no difference between them. Black bean presented the highest dietary fiber, resistant starch, and total indigestible fraction contents. The highest polyphenols and anthocyanins contents were shown by lentil and black bean, respectively. However, black bean exhibited the highest antioxidant capacity, which suggess an important role for anthocyanins in this effect. Present data confirm these legumes as a good source of indigestible carbohydrates and natural antioxidants; their consumption might have a role in preventing diabetes and other chronic-degenerative diseases.

Pasta with unripe banana flour: physical, texture, and preference study.

Banana is a starchy food that contains a high proportion of undigestible compounds such as resistant starch and nonstarch polysaccharides. Products with low glycemic response such as pasta are considered favorable to health. The objective of this study was to use unripe banana flour to make spaghetti with low-carbohydrates digestibility and evaluate its physical and texture characteristics, as well as consumer preference. Formulations with 100% durum wheat semolina (control) and formulations with 3 semolina: banana flour ratios (85: 15, 70: 30, and 55: 45) were prepared for spaghetti processing. The use of banana flour decreased the lightness and diameter of cooked spaghetti, and increased the water absorption of the product. Hardness and elasticity of spaghetti were not affected by banana flour, but adhesiveness and chewiness increased as the banana flour level in the blend rose. Spaghettis prepared in the laboratory (control and those with banana flour) did not show differences in preference by consumers. In general, the preference of spaghettis with different banana flour level was similar. The addition of a source of undigestible carbohydrates (banana flour) to spaghetti is possible without affecting the consumer preference.

PASTA ADDED WITH CHICKPEA FLOUR: CHEMICAL COMPOSITION, IN VITRO STARCH DIGESTIBILITY AND PREDICTED GLYCEMIC INDEX PASTA ADICIONADA CON HARINA DE GARBANZO: COMPOSICIÓN QUÍMICA, DIGESTIBILIDAD IN VITRO DEL ALMIDÓNY PREDICCIÓN DEL ÍNDICE GLUCÉMICO

Abstract Pasta was prepared with of durum wheat flour mixed with chickpea flour at two different levels and its chemical composition, in vitro starch digestibility and predicted glycemic index were assessed. Protein, ash, lipid, and dietary fiber content increased while total starch decreased with the chickpea flour level in the composite pasta, all in accordance to the composition of the legume flour. Potentially available starch decreased and resistant starch (RS) increased by adding chickpea flour to the pasta. The main indigestible starch component in composite spaghetti was the fiber-associated RS, representing up to 50 % of total RS levels. The starch hydrolysis index (HI) decreased as chickpea flour in the pasta increased, reflecting the slow and low digestion of the starch in the leguminous ingredient. Predicted glycemic index was lower in spaghetti added with chickpea flour than in durum wheat-control pasta. Pasta added with chickpea flour might be a dietetic alternative for people with low-calorie requirements. Resumen Se elaboró pasta mezclando sémola de trigo con harina de garbanzo a dos niveles y se evaluó su composición química, digestibilidad del almidón in vitro y se predijo el índice glucémico. El contenido de proteína, ceniza, lípidos y fibra dietética incrementó mientras que el almidón total disminuyó con el contenido de harina de garbanzo en la pasta, esto debido a la composición de la harina de la leguminosa. El contenido de almidón disponible disminuyó y el almidón resistente (AR) incrementó con la adición de la harina de garbanzo a la pasta. El principal componente del almidón no digestible en el espagueti con harina de garbanzo fue el AR asociado a fibra, que representó más del 50 % del AR total. El índice de hidrólisis (IH) del almidón disminuyó con el incrementó del nivel de harina de garbanzo en la pasta, reflejando la baja y lenta digestión del almidón de la leguminosa. La predicción del índice glucémico fue menor en el espagueti adicionado con harina de garbanzo que la muestra control. La pasta adicionada con harina de garbanzo puede ser una alternativa dietética para personas con bajos requerimientos calóricos. Palabras clave: Índice glucémico, composición química, pasta, garbanzo, almidón resistente, fibra dietética