Numerous reactive oxygen species (ROS) entities exist, and hydrogen peroxide (H2O2) is very key among them as it is well known to possess a stable but poor reactivity capable of generating free radicals. Considered among reactive atoms, molecules, and compounds with electron-rich sites, free radicals emerging from metabolic reactions during cellular respirations can induce oxidative stress and cause cellular structure damage, resulting in diverse life-threatening diseases when produced in excess. Therefore, an antioxidant is needed to curb the overproduction of free radicals especially in biological systems (in vivo and in vitro). Despite the inherent properties limiting its bioactivities, polysaccharides from natural sources increasingly gain research attention given their position as a functional ingredient. Improving the functionality and bioactivity of polysaccharides have been established through degradation of their molecular integrity. In this critical synopsis; we articulate the effects of H2O2 on the degradation of polysaccharides from natural sources. Specifically, the synopsis focused on free radical formation/production, polysaccharide degradation processes with H2O2, the effects of polysaccharide degradation on the structural characteristics; physicochemical properties; and bioactivities; in addition to the antioxidant capability. The degradation mechanisms involving polysaccharide’s antioxidative property; with some examples and their respective sources are briefly summarised.

A process for enhancing textural and cooking properties of fresh rice flour‐soy protein isolate noodles (RNS) to match those of yellow alkaline noodles (YAN) was developed by incorporating microbial transglutaminase (RNS‐MTG), glucono‐δ‐lactone (RNS‐GDL), and both MTG and GDL into the RNS noodles (RNS‐COM). The formation of γ‐glutamyl‐lysine bonds in RNS‐COM and RNS‐MTG was shown by sodium dodecyl sulfate polyacrylamide gel electrophoresis. Scanning electron microscope showed that compared to others, the structure of RNS‐COM was denser, smoother with extensive apparent interconnectivity of aggregates. The optimum cooking time was in the order: YAN > RNS‐COM > RNS‐MTG > RNS‐GDL > RN (rice flour noodles); tensile strength was in the order: YAN > RNS‐COM > RNS‐MTG > RNS‐GDL > RN; and elasticity were in the order: YAN > RNS‐COM > RNS‐MTG, RNS‐GDL > RN. Overall, RNS‐COM showed similar textural and structural breakdown parameters as compared to those of YAN. Changes in microstructures and improvement of RNS‐COM in certain properties were likely due to enhanced crosslinking of proteins attributed to MTG‐ and GDL‐induced cold gelation of proteins at reduced pH value. It is possible to use the combination of MTG and GDL to improve textural and mechanical properties of RNS comparable to those of YAN. Practical Application Combined MTG and GDL yield rice flour noodles with improved textural properties. The restructured rice flour noodles have the potential to replace yellow alkaline noodles.

The colour of rice syrup produced from flours of malted and unmalted rice of different varieties treated with a combination of starch hydrolyzing enzymes were analysed using CIE-LAB Spectrophotometric colorimeter after being filtered and/or centrifuged. The resulting syrups were processed as filtered unmalted hydrolyzed rice (FUHR), filtered malted hydrolyzed rice (FMHR), centrifuged unmalted hydrolyzed rice (CUHR) and centrifuged malted hydrolyzed rice (CMHR). Results showed that L* ranged from 60.16 to 68.57, a* ranged from 10.49 to 11.13 and b* ranged from 55.34 to 64.56. The magnitude of the colour values was an indication of the intensity of the rice syrup colour. Hue angle (oH*) ranged from 79.08o to 80.36o indicating less yellow in the CIE-LAB colour space and brown colour spectrum in the visible region of opponent colour chart. Total colour difference (ΔE) of syrups ranged from 0.50 to 1.72 for ΔEunmalted while ΔEmalted ranged from 0.49 to 1.76. However, the ΔEfiltered ranged from 5.89 to 11.19 while ΔEcentrifuged ranged from 5.54 to 9.47 indicating that filtration and centrifugation contributed to non-significant difference (p>0.05) in colour attributes (ΔE) of the rice syrup, whereas very distinct colour difference (ΔE) was observed between rice syrups from malted and unmalted samples.