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Introduction: Introduction: resistant starch (RS) is not completely digested in the human intestine but is fermented in the colon; intestinal pH decreases as short-chain fatty acids are produced. This is beneficial for health, and for preventing and treating rectal colon cancer. Pyrodextrinization and enzymatic hydrolysis are modifications to native starch (NS) that may increase the amount of RS. Objective: the objective of this project was to evaluate the effects of M. cavendish AAA native and both chemically and enzymatically modified starches on tumor markers in rats. Methods: modifications (chemical and enzymatic) were made to M. cavendish AAA NS, and were evaluated in rats with 1,2-DMH. Male Sprague Dawley rats (25) were used, divided into five experimental groups: PC, NC, NS, PI, and ERM. During 4 weeks they received the experimental diet assigned to each group. The PC, NS, PI and ERM groups received 2 weekly s.c. (subcutaneous) injections of 1,2-DMH (40 mg/kg) (third and fourth week). In feces, pH, β-glucuronidase enzyme, and short-chain fatty acids were evaluated, and a histopathological study was performed of the intestine to detect microscopic lesions. Results: the activity of β-glucuronidase decreased (p < 0.05) for NS, PI and ERM vs. PC. The highest proportion of butyric acid was observed in the NS (p < 0.05) vs. NC group. Sixty percent of enteritides were severe in grade in the PC group, and 40 % in the experimental groups. Conclusions: native starch granules resisted pyrodextrinization, but treatment with α-amylase broke the structure of the pyrodextrin granule. According to the treatments given to the rats, as the amount of RS present in the diet increases (NS), the neoplastic cells do not advance beyond the basement membrane, suggesting a possible cell-protective or anticancer effect.

Introduction: insulin resistance (IR) is the preliminary stage of diseases such as diabetes and hypertension. These diseases can be controlled through medication, yet the consumption of functional foods (FF) may be one complementary treatment option. Ingredients for these FF could be the pyrodextrin and enzymatically resistant maltodextrin (ERM) obtained from the native starch (NS) of M. cavendishin this study., Objective: to evaluate the effects of modified banana starch on glycemic control and blood pressure in rats with high sucrose diet (HSD)., Methods: we utilized 25 male Wistar rats 20 of which received a HSD and five were fed a normal diet and purified water (PW) for 12 weeks. At the end of week 8, the rats fed a HSD were divided into four groups: positive control (PC), native starch (NS), pyrodextrin (PI), and enzymatically resistant maltodextrin (ERM). The negative control (NC) comprised the five rats fed PW. We evaluated the glucose tolerance test, blood pressure (BP), insulin levels, total cholesterol (TC), high-density lipoproteins (HDL), and triglycerides., Results: differential scanning calorimetry and scanning electron microscopy of the modified starches demonstrated that the pyroconversion treatment did not visibly affect the NS granules, while ERM was modified by the action of α-amylase. Starch treatments reduced glucose, insulin, HOMA-IR, and BP in comparison with PC (p < 0.05). Glucose AUC (0-120 min) was also decreased after starch treatments with respect to PC (p < 0.05)., Conclusion: NS and its modified products exerted beneficial effects on glycemic control, lipid metabolism, and BP in obese rats fed a HSD. Although the modified starches presented lower resistance to digestion than NS, their expected properties were maintained.

Cassava (Manihot esculenta Crantz) native starch was treated with pyroconversion and enzymatic hydrolysis to produce a pyrodextrin and an enzyme-resistant maltodextrin. Some nutritional characteristics were quantified for both compounds. Pyroconversion was done using a 160:1 (p/v) starch:HCl ratio, 90 °C temperature and 3 h reaction time. The resulting pyrodextrin contained 46.21% indigestible starch and 78.86% dietary fiber. Thermostable α-amylase (0.01%) was used to hydrolyze the pyrodextrin at 95 °C for 5 min. The resulting resistant maltodextrin contained 24.45% dextrose equivalents, 56.06% indigestible starch and 86.62% dietary fiber. Compared to the cassava native starch, the pyrodextrin exhibited 56% solubility at room temperature and the resistant maltodextrin 100%. The glycemic index value for the resistant maltodextrin was 59% in healthy persons. Its high indigestible starch and dietary fiber contents, as well as its complete solubility, make the resistant maltodextrin a promising ingredient for raising dietary fiber content in a wide range of foods, especially in drinks, dairy products, creams and soups.

Seeds from avocado (Persea americana Miller) fruit are a waste byproduct of fruit processing. Starch from avocado seed is a potential alternative starch source. Two different extraction solvents were used to isolate starch from avocado seeds, functional and rheological characteristics measured for these starches, and comparisons made to maize starch. Avocado seed powder was suspended in a solution containing 2 mM Tris, 7.5 mM NaCl and 80 mM NaHSO3 (solvent A) or sodium bisulphite solution (1500 ppm SO2, solvent B). Solvent type had no influence (p>0.05) on starch properties. Amylose content was 15-16%. Gelatinization temperature range was 56-74 °C, peak temperature was 65.7 °C, and transition enthalpy was 11.4-11.6J/g. At 90 °C, solubility was 19-20%, swelling power 28-30 g water/g starch, and water absorption capacity was 22-24 g water/g starch. Pasting properties were initial temperature 72 °C; maximum viscosity 380-390 BU; breakdown -2 BU; consistency 200 BU; and setback 198 BU. Avocado seed starch dispersions (5% w/v) were characterized as viscoelastic systems, with G'>G″. Avocado seed starch has potential applications as a thickening and gelling agent in food systems, as a vehicle in pharmaceutical systems and an ingredient in biodegradable polymers for food packaging., (Copyright © 2016. Published by Elsevier B.V.)

In this paper, the Ramon starch was isolated and its chemical composition and physical and microscopic characteristics were determined. Corn starch was used as reference. In general, the proximal composition was similar between starches studied. Ramon starch granules were oval-spherical and rounded with sizes between 6.5 and 15 μm. Starch purity was high (92.57%) with amylose content of 25.36%. The gelatinization temperature was 83.05°C and transition enthalpy was 21.423 J/g. At 90°C, solubility was 20.42%, swelling power 17.64 g water/gstarch and water absorption capacity was 13 gwater/gstarch. The pH, clarity and color (Hue angle) of Ramon starch were higher to those reported for corn starch. The results achieved suggest that Ramon starch has potential for application in food systems requiring high processing temperatures and it is also a promising option for use in the manufacture of biodegradable materials., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

Extrusion is used to produce crunchy expanded foods, such as snacks. The nutritional impact of this process has not been studied sufficiently. In this study, in vitro and in vivo protein and starch bioavailability was evaluated in both raw and extruded corn (Zea mays)(C) and lima bean (Phaseolus lunatus)(B) flour blends, prepared in 75C/25B and 50C/ 50B (p/p) proportions. These were processed with a Brabender extruder at 160 degrees C, 100 rpm and 15.5% moisture content. Proximate composition showed that in the extruded products protein and ash contents increased whereas the fat level decreased. In vitro protein digestibility was higher in the extrudates (82%) than in the raw flours (77%). Potentially available starch and resistant starch contents decreased with extrusion. The in vitro assays indicated that extrusion improved protein and starch availability in the studied blends. In vivo bioavailability was evaluated using the rice weevil (Sithophilus oryzae) as a biological model. The most descriptive biomarkers of the changes suggested by the in vivo tests were body protein content (increased by extrusion) and intestinal a-amylase activity (decreased by processing). Overall, results suggest that extrusion notably increases the nutritional quality of corn and lima bean flour blends.

Incorporation into cookies of prime and tailing starches isolated from Phaseolus lunatus and Canavalia ensiformis seeds was carried out and compared with those elaborated with conventional corn starch (Maizena), which were sensory evaluated and assessed for total dietary fiber (TDF), insoluble dietary fiber (IDF) and soluble dietary fiber (SDF) contents. Sensory evaluation was carried out using an incomplete block design by a non-trained panel of judges. The analysis of variance indicated a significant difference (p < 0.05), in the level of acceptation, among the different formulations; cookies elaborated with prime starches were preferred. Cookies elaborated with the tailing starches and the control cookie had similar acceptance. The cookies prepared with tailing starches presented TDF, IDF and SDF contents of 9.3, 4.86 and 4.87%, respectively for C. ensiformis and of 9.85, 8.75 and 1.10%, for P. lunatus. These contents were higher than those found in other cookies. The use of prime and tailing starches of Canavalia ensiformis and Phaseolus lunatus may represent an effective alternative in manufacturing of fiber-rich bakery products.

Abstract: Phaseolus lunatus starch was modified by esterification with octenyl succinic anhydride (OSA) and reaction effect evaluated in terms of chemical composition, gelatinization, pasting and emulsification properties. Succinylation was done using a 23 factorial design with four replicates of the central treatment. Evaluated factors and levels were OSA concentration (1% and 3%), pH (7 and 9) and reaction time (30 and 60min). Succinyl group percentage was the response variable. The optimum treatment was a reaction with 3% OSA at pH 7 for 30min, which produced 0.5083% succinyl groups and 0.0083° of substitution. No significant changes were observed in proximate composition between the native and derivative starches. Apparent amylose level decreased notably from 32.4% to 23.6% due to OSA inclusion. Succinylation decreased starch gelatinization temperature (75.3–64.6°C), decreased enthalpy (10.7–9.7J/g), increased viscosity (700–1000BU), increased emulsifying capacity (0.47–0.53ml oil/ml sample), and made emulsions more stable over time. Starch modification did not, however, improve stability in heating–cooling processes. [Copyright &y& Elsevier]

The properties of starch from parota ( Enterolobium cyclocarpum ) isolated by three methods, sodium bisulfite (M1), distilled water (M2) and acid steeping (M3), were assessed. The properties studied included: proximal composition, physicochemical characteristics, morphology of starch granules, swelling power and solubility, fourier transform infrared spectroscopy (FTIR) and thermal behavior. Results showed that the starch isolation method induced changes in most of these properties. The highest starch yield was obtained with method M1, with an average purity of 84%. In addition, a greater quantity of protein was removed (a similar behavior was observed with method M3), larger granules were obtained and the starch was whiter in comparison with the other methods. However, method M1 also presented the lowest quantity of amylose (17.5%), poorer starch paste clarity and required more energy for gelatinization. With the use of method M2, it was possible to observe the formation of cracks in the starch granule. The starches extracted with methods M2 and M3 showed greater swelling power and solubility. The method of isolation employed had no influence on the FTIR spectra. In conclusion, the starch isolated with M1 presented the best properties for use in the food industry. [ABSTRACT FROM AUTHOR]

Endosperm of nixtamalized corn was analyzed using X-ray diffraction. Relative crystallinity changed with lime concentration and steeping. Diffractograms showed peaks corresponding to V-type crystalline structures, indicating formation of complexes during cooking and steeping. Diffraction patterns of the soluble fraction showed that complexed amylose can be leached out during solubilization. While diffraction patterns of the insoluble fraction suggested that some of the formed complexes remain in this fraction. During alkali steeping, release of amylose is strongly inhibited as indicated by the pronounced decrease in the starch–I2 absorbance of the lime treated samples compared to the lime-free treated sample. This decrease is interpreted as evidence of starch cross-linking during the nixtamalization process. Differences in starch–I2 absorbance and in X-ray diffraction patterns of the soluble fractions suggested that lime treatment could also modified formation of amylose complexes with lipids. [Copyright &y& Elsevier]