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The aim of this work is to reinforce particulate porous SiC samples by the in situ synthesis of β-Si3N4 nanofibers within the porous samples by the chemical vapor infiltration method without catalytic metallic precursors. The experiment considered the variation of the reaction time (1, 2, 3, and 4 h) and the N2 flow rate (3, 5, and 9 cm3/min); while the inner pressure (10 mbar), the thermal decomposition of the solid precursor Na2SiF6 (400°C), and the temperature of the SiC sample (1300°C) remained constant. The mechanical properties of the composites revealed a non-linear behavior due to the arrangement of the particles during the loading process and to the plastic properties of the β-Si3N4 nanofibers. The stress and strain energy density magnitudes for different times had a rising behavior up to 3 h (σ = 15.65 MPa and u = 2.41 MJ/m3) due to the increasing diameter (100 to 200 nm) and quantity of β-Si3N4 nanofibers; while, at 4 h were significantly decreased (σ = 8.83 MPa and u = 1.44 MJ/m3) based on the reduction of the β-Si3N4 nanofiber diameter (30 to 100 nm) and to the presence of a new phase (Si2N2O). [ABSTRACT FROM AUTHOR]

It is well known that using retrograded starches confers many technological advantages, as well as health benefits when consumed in adequate doses; however, these properties are closely related to the type of starch and/or the treatment applied, therefore, it is of interest to add retrograded starch to popular products such as Greek yogurt. The aim of this work was to investigate the effect of adding two types of retrograded corn starch with different amylose content to a non-strained type of Greek-style yogurt. Retrograded starch from starch containing 27 % (RNS) or 70 % (RHS) amylose was added to yogurt at 0, 10, 12.5, or 15 g/100 g before storage at 4 °C for 14 d. The resistant starch (RS) content, pH, syneresis, flow behavior index, and consistency index, were measured every week. A sensory test was carried out in yogurt added with 12.5 g/100 g of retrograded starches to evaluate acceptance. Adding retrograded starch significantly reduced syneresis while increased the consistency, firmness, and resistant starch content of the yogurt. No significant differences in general acceptance were observed in samples added with RNS when compared to the control. Although a significant difference was observed after adding RHS, the acceptance of the product is still convenient. Adding a high concentration of retrograded starch could help to ensure doses enough for a prebiotic effect of RS with concentrations of 1.74 ± 0.37 to 2.32 ± 0.09 g/100 g and from 3.5 ± 0.08 to 4.21 ± 0.08 g/100 g when RNS or RHS is added respectively, while maintaining the quality characteristics of Greek-style yogurt during storage without compromising the acceptability., Competing Interests: Declaration of competing interest We state that there is no actual or potential conflict of interest related to the document titled “Effect of adding high concentrations of retrograded starch with different amylose content on the physicochemical properties and sensory attributes of Greek-style yogurt”. This project was financially supported by Instituto Politecnico Nacional through SIP20196083, SIP20200568 and SIP20211175 grants., (Copyright © 2023 Elsevier B.V. All rights reserved.)

The aim of this study was to evaluate the effect of acid hydrolysis and succination upon single and a combination of both of them as a dual modification on the morphological, structural, thermal, and pasting profile of the achira starch in order to expand its potential food applications. The surface of achira starch granules was eroded with acid hydrolysis, while the succination resulted in the formation of pores or cavities, having a slight impact on the crystallinity and the gelatinization enthalpy. Succinated starch presented the lowest transition temperatures (To = 60.29 °C, Tp = 65.03 °C and Te = 69.86 °C) compared to other starches in this study. The succination increased the final viscosity (3808 cp) when compared with the native starch (3114 cp), while acid hydrolysis resulted in a decreased value (735 cp). These are desirable properties for its possible use as an additive in bakery industry processes., (© Association of Food Scientists & Technologists (India) 2020.)

Banana starch was isolated and used for preparation of two types of cookies. Chemical composition and digestibility tests were carried out on banana starch and the food products, and these results were compared with corn starch. Ash, protein, and fat levels in banana starch were higher than in corn starch. The high ash amount in banana starch could be due to the potassium content present in this fruit. Proximal analysis was similar between products prepared with banana starch and those based on corn starch. The available starch content of the banana starch preparation was 60% (dmb). The cookies had lower available starch than the starches while banana starch had lower susceptibility to the in vitro alpha-amylolysis reaction. Banana starch and its products had higher resistant starch levels than those made with corn starch.