The compositional, physicochemical and functional properties of germinated mung bean flour and its addition on quality of wheat flour noodle.

Despite sprouted grains have high nutritional and functional properties, their exploration in mung bean and application in traditional foods are limited. The effects of germination of mung bean for 12, 24, 36, 48, 60 and 72 h on compositional, physicochemical and functional properties of its flour were investigated. The effects of incorporation of germinated mung bean flour at different levels (0, 10, 20 and 30%) on noodles making properties of wheat flour were evaluated 0. The protein content increased while the amylose increased initially and then decreased with increase in germination time. Water absorption index, oil binding capacity and water retention capacity increased, while water soluble index initially increased and then decreased. The germinated mung bean flour became darker with increase in germination time. The protein bound to starch in noodlesed to increase in hardness, cohesiveness, gumminess, chewiness, resilience and cooking time of noodles. Additionally, the water absorption, cooking loss, adhesiveness and springiness of raw noodles and springiness, cohesiveness and chewiness of cooked noodles decreased with the addition of germinated flour.

The phenolic compounds profile, quantitative analysis and antioxidant activity of four naked barley grains with different color.

In the present study, the profile of phenolic compounds in colored (white, yellow, black and blue) naked barley was detected and their content and antioxidant abilities were investigated. The results showed that there were 156 phenolic substances identified, including monophenol, phenolic acids, flavonoids and other polyphenols. The black sample had the most types of phenolic. The content of phenolic varies depending on color of naked barley and the highest values of total phenolic acid and total flavonoids were observed in black and white samples. Furthermore, the strongest ferric reducing antioxidant power and the free radical scavenging ability of DPPH, ABTS, and superoxide anion showed in white, white, yellow and black naked barley. While white and yellow samples had the strongest scavenging ability of hydroxyl radical. There was significant correlation between phenolic components and anti-oxidation. This study suggests that colored naked barley grains are rich in phenolic compounds with antioxidant capacity.

Molecular, crystal and physicochemical properties of granular waxy corn starch after repeated freeze-thaw cycles at different freezing temperatures.

The study was undertaken to reveal the effects of freeze-thaw cycles at different freeze temperature (-20 °C, -40 °C and -80 °C) and the number of freeze-thaw cycles (3, 6, 12, 18, 24 times) on physicochemical and structural properties of waxy corn starch. The number of pores on the surface of starch granules increased, but there was no significant (P < 0.05) effect on molecular weight, transparency, freeze-thaw stability and the crystal structure of starch after repeated freeze-thaw cycle. But the crystallinity intensity decreased after freeze-thaw cycles treatment and a tiny decrease in onset, peak, conclusion temperature and gelatinization enthalpy were found. The RVA analysis exhibited an increase in gelatinization temperatures and a decrease in breakdown and setback value after freeze-thaw treatment, which manifested an increase in the aging and heat resistance of waxy corn starch paste. However, there was no statistical (P < 0.05) difference between different freeze temperatures at the same number of freeze-thaw cycle on physicochemical and structural properties of starch. The obtained data could be helpful in evaluation of the repeated freeze-thaw treatment of waxy corn starch-based foodstuffs and providing the theoretical basic for revealing the effect of repeated freeze-thaw processes in manufacture applications.

The Comparison of Structural, Physicochemical, and Digestibility Properties of Repeatedly and Continuously Annealed Sweet Potato Starch.

In order to investigate the varied effects of repeated annealing treatment (RANN) and continuous annealing treatment (CANN) on the structural, physicochemical, and digestibility properties of the sweet potato. The 75% starch-water suspensions were prepared and incubated at 65 °C for 8 cycles and 96 hr. The results exhibited that RANN and CANN did not influence the starch granules and polarization cross obviously. The crystal type of RANN and CANN starches still maintained A-type, while the relative crystallinity increased. The solubility, swelling power, peak viscosity and breakdown of RANN and CANN starches decreased, but the gelatinization transition temperatures, trough viscosity, final viscosity, setback, and pasting temperatures of starches increased after annealing treatments. Furthermore, RANN and CANN decreased the RS and RS + SDS contents with the increase of annealing cycles and time. The RANN was more effective in modification of the crystallinity, solubility, swelling power, pasting, gelatinization transition temperatures and enthalpy, and digestibility of starch before four times compared with the CANN ones. By and large, RANN may be a potential way for modification of structural, physicochemical and digestibility properties. PRACTICAL APPLICATION: The described RANN and CANN starch provide new ideas for the study of modified starch. Furthermore, this study revealed the mechanism of annealing treatment and it was concluded that the repeated annealing treatment could provide a new potential way for the modification of starch.

Effects of repeated and continuous dry heat treatments on properties of sweet potato starch.

The influence of repeated and continuous dry heat treatments on structural, physicochemical, and digestive properties of sweet potato starch was investigated. The results showed that the original A-type crystallinity of sweet potato starch remained unchanged after dry heat treatments. The light transmittance, gelatinization temperature, and pasting temperature of sweet potato starch increased; while the pasting viscosities, swelling power, and solubility decreased after dry heat treatments. Relative crystallinity, solubility, swelling power, light transmittance, and thermal parameter values (To, Tp, Tc, ΔT) were found to be significantly higher for the continuous dry heat (CDH) treated starch than those of the repeated dry heat (RDH) treated starch after treatment for the same duration. However, CDH treated starch samples showed lower paste viscosity and digestibility than those of RDH treated samples after treatment for the same duration. In addition, the CDH treatment highly influenced the structure of starch granule surface compared with the RDH treatment. Generally, it can be concluded that RDH treatment highly influenced structural, physicochemical, and digestive properties of sweet potato starch compared with CDH treatment.

The effect of repeated versus continuous annealing on structural, physicochemical, and digestive properties of potato starch.

Native potato starch was suspended in distilled water at starch: water ratio of 1:3 (w/v). The starch-water suspensions were then subjected to repeated annealing treatments (RANN) at 55 °C for 12 h, repeated for 8 cycles or continuous annealing treatments (CANN) at 55 °C for 24, 48, 72 and 96 h. The structural, physiochemical and digestive properties of the annealed starch samples were studied and compared with those of the native starch. The scanning electron microscopy and light microscopy analysis showed that the repeated and continuous annealing treatments could keep the integrity and surface perfection of the starch granules. The growth rings of the annealed starch granules were more distinct than those of the native starch granules as revealed by confocal laser scanning microscopy. The crystallinity degree increased and the crystalline retained the B-type pattern after the annealing treatments. There were no chemical bonds and functional groups produced or disappeared during the applied annealing treatments. Infrared absorption peak intensity of starch decreased and short-range ordered structures increased after treatments. The swelling power and solubility decreased at low temperature (50 to 60 °C) and increased at relatively high temperature (70 to 90 °C). The rapid visco-analyzer and differential scanning calorimeter analysis revealed an increase in the setback, final viscosity, pasting temperature and gelatinization transition temperature, and a decrease in breakdown value of the starch after the annealing treatments. On the other hand, the repeated and continuous annealing treatments resulted in starch with low in vitro digestibility degree, indicating formation of resistant starch. Generally, the repeated annealing treatment resulted in starch with high improved properties compared with the starch resulted from the continuous annealing treatments. Therefore, the repeated annealing treatments can be suggested as an effective method for producing of modified starch for food industrial applications.