RESUMEN
Due to functional and physicochemical properties, starch in its native state has limited range of applications. Simultaneously, information on effects of different sugars and their interactions with modified starch on gluten-free model dough is also limited. To better overcome these restrictions, the effects of sucrose, trehalose, maltose and xylose on rheology, water mobility and microstructure of gluten-free dough prepared with high hydrostatic pressure (HHP) treated maize (MS), potato (PS) and sweet potato starch (SS) were investigated. MS, PS and SS dough with trehalose exhibited a lower degree of dependence of G' on frequency sweep (z'), higher strength (K) and relative elastic part of maximum creep compliance (Je/Jmax), suggesting stable network structure formation. Total gas production (VT) of MS dough with maltose, PS dough with sucrose and SS dough with trehalose was increased from 588 to 1454 mL, 537 to 1498 mL and 637 to 1455 mL respectively. Higher weakly bound water (T22) was found in the dough with trehalose at 60 min of fermentation, suggesting more hydrogen bonds and stable network. Thus, trehalose might be a potential improver in HHP treated starch-based gluten-free products.
Asunto(s)
Maltosa , Trehalosa , Xilosa , Sacarosa , Agua/química , Presión Hidrostática , Almidón/química , Reología , Glútenes/química , HarinaRESUMEN
Effects of high hydrostatic pressure (HHP, 100, 300 and 500 MPa for 30 min at 25 °C) treated maize (MS), potato (PS), and sweet potato (SS) starches on thermo-mechanical, rheological, microstructural properties and water distribution of gluten-free model doughs were investigated. Significant differences were found among starch model doughs in terms of water absorption, dough development time, and dough stability at 500 MPa. Total gas production of MS, PS and SS doughs was significantly increased from 541 to 605 mL (300 MPa), 527 to 568 mL (500 MPa) and 551 to 620 mL (500 MPa) respectively as HHP increased. HHP increased storage (G') and loss (Gâ³) modulus in terms of rheological properties suggesting, the higher viscoelastic behavior of starch model doughs. The dough after 500 MPa treatment showed lower degree of dependence of G' on frequency sweep suggesting, the formation of a stable network structure. In addition, continuous abundant water distribution and uniform microstructure were found in MS (300 MPa), PS (500 MPa) and SS (500 MPa) doughs for 60 min fermentation. Thus, the starches after HHP show great application potential in gluten-free doughs with improved characteristics.
Asunto(s)
Ipomoea batatas , Solanum tuberosum , Presión Hidrostática , Ipomoea batatas/química , Reología , Solanum tuberosum/química , Almidón/química , Zea mays/químicaRESUMEN
Sweet potato leaf polyphenols (SPLPs) have shown potential health benefits in the food and pharmaceutical industries. Nowadays, consumption of SPLPs from animal feeds to foodstuff is becoming a trend worldwide. However, the application of SPLPs is limited by their low bioavailability and stability. ß-lactoglobulin (ßlg), a highly regarded whey protein, can interact with SPLPs at the molecular level to form reversible or irreversible nanocomplexes (NCs). Consequently, the functional properties and final quality of SPLPs are directly modified. In this review, the composition and structure of SPLPs and ßlg, as well as methods of molecular complexation and mechanisms of formation of SPLPsßlgNCs, are revisited. The modified functionalities of SPLPsßlgNCs, especially protein conformational structures, antioxidant activity, solubility, thermal stability, emulsifying, and gelling properties including allergenic potential, digestibility, and practical applications are discussed for SPLPs future development.
Asunto(s)
Ipomoea batatas , Polifenoles , Animales , Antioxidantes , Lactoglobulinas , Extractos Vegetales , Hojas de la PlantaRESUMEN
Milk proteins and polyphenols are increasingly being studied as functional ingredients due to the epidemiologically-proved health benefits. In this study, composite ß-lactoglobulin (ß-lg) or ß-lactoglobulin nanoparticles (ß-lgNPs)-3,5-di-O-caffeoylquinic acid (3,5diCQA) with superior physicochemical and antioxidant activity (AA) were produced using ß-lg and 3,5-di-O-caffeoylquinic acid. The main interactions between ß-lg or ß-lgNPs with 3,5diCQA were hydrogen bonding and hydrophobic effects. The 3,5diCQA caused a decrease in α-helix and ß-sheet structure with a corresponding increase in unordered structure. Compared to ß-lg alone, composite ß-lg or ß-lgNPs-3,5diCQA slightly decreased the particle size but increased their negative surface potentials especially for ß-lg or ß-lgNPs at a molar ratio of 5:1. The addition of 3,5diCQA appreciably improved the AA in a dose-dependent manner. These results shed light on the structural, physicochemical, and AA of composite ß-lg or ß-lgNPs-3,5diCQA non-covalent complexes, important for application as functional ingredients in food solutions as well as in the pharmaceutical industry.
Asunto(s)
Antioxidantes/química , Ácido Clorogénico/análogos & derivados , Lactoglobulinas/química , Nanopartículas/química , Animales , Ácido Clorogénico/química , Ácido Clorogénico/metabolismo , Enlace de Hidrógeno , Interacciones Hidrofóbicas e Hidrofílicas , Lactoglobulinas/metabolismo , Tamaño de la Partícula , Conformación Proteica en Hélice alfa , Conformación Proteica en Lámina betaRESUMEN
The effect of high hydrostatic pressure (HHP) on the susceptibility of potato starch (25%, w/v) suspended in water to degradation by exposure to bacterial α-amylase (0.02%, 0.04% and 0.06%, w/v) for 40 min at 25°C was investigated. Significant differences (p < 0.05) in the structure, morphology and physicochemical properties were observed. HHP-treated potato starch (PS) exposed to α-amylase (0.06%, w/v) showed a significantly greater degree of hydrolysis and amount of reducing sugar released compared to α-amylase at a concentration of 0.04% (w/v) or 0.02% (w/v). Native PS (NPS) granules have a spherical and elliptical form with a smooth surface, whereas the hydrolyzed NPS (hNPS) and hydrolyzed HHP-treated PS granules showed irregular and ruptured forms with several cracks and holes on the surface. Hydrolysis of HHP-treated PS by α-amylase could decrease the average granule size significantly (p <0.05) from 29.43 to 20.03 µm. Swelling power decreased and solubility increased with increasing enzyme concentration and increasing pressure from 200-600 MPa, with the exception of the solubility of HHP-treated PS at 600 MPa (HHP600 PS). Fourier transform infrared spectroscopy (FTIR) showed extensive degradation of the starch in both the ordered and the amorphous structure, especially in hydrolyzed HHP600 PS. The B-type of hydrolyzed HHP600 PS with α-amylase at a concentration 0.06% (w/v) changed to a B+V type with an additional peak at 2θ = 19.36°. The HHP600 starch with 0.06% (w/v) α-amylase displayed the lowest value of To (onset temperature), Tc (conclusion temperature) and ΔHgel (enthalpies of gelatinization). These results indicate the pre-HHP treatment of NPS leads to increased susceptibility of the granules to enzymatic degradation and eventually changes of both the amorphous and the crystalline structures.
Asunto(s)
Presión Hidrostática , Solanum tuberosum/enzimología , Almidón/metabolismo , alfa-Amilasas/metabolismo , Rastreo Diferencial de Calorimetría , Microscopía Electrónica de Rastreo , Proteolisis , Espectroscopía Infrarroja por Transformada de FourierRESUMEN
The effects of high hydrostatic pressure (HHP) on emulsifying properties of sweet potato protein (SPP) in presence of 0.1%, 0.3% and 0.5% (w/v) of guar gum (GG) and glycerol monostearate (GMS) were investigated. Emulsifying stability index (ESI) of the SPP with GG revealed significant increase (P<0.05) in ESI value at 600MPa treatment, while the stability of SPP-GMS emulsions significantly decreased with increase in GMS concentrations and HHP treatments (200-600MPa). HHP treatment considerably reduced the creaming rate for SPP-GG model while such case was not observed for SPP-GMS model. The flow index for SPP-GG emulsion model was found to decrease with increase in HHP treatment and had non-Newtonian behaviour. The SPP-GMS emulsion models with HHP treatments showed comparatively lower viscosities but had more Newtonian flow character.