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Summary: This study aimed to evaluate the thermal inactivation kinetics of polyphenol oxidase (PPO) and peroxidase (POD) in starfruit juice. It followed the Malaysia Food Regulations 1985 and CODEX STAN 247‐2005. Glucose, fructose and sucrose were the main sugars in starfruit juice. The total soluble solids, pH, titratable acidity, and total phenolics content of the starfruit juice produced were 8.13 ± 0.25 °Brix, 3.80 ± 0.05, 0.43% ± 0.02% malic acid, and 93.67 ± 4.96 mg GAEL−1, respectively. Thermal inactivation kinetics of PPO and POD followed the first‐order kinetic model. The decimal reduction time at 83.6 °C (D83.6) of PPO and POD was 198.48 and 98.4 s, respectively, while the thermal resistance constant (z value) of PPO and POD was 12.8 and 5.4 °C, respectively. In conclusion, PPO might be a suitable signal for thermal processing on starfruit juice since it has higher heat resistance than POD. [ABSTRACT FROM AUTHOR]

Summary: In this study, the effects of steaming treatments during the preparation of structurally enhanced air‐dried rice noodles were investigated. Soy protein isolate‐rice noodles (RNS) were combined (COM) with microbial transglutaminase (MTG) and glucono‐δ‐lactone (GDL), and steamed for 5 (S5) or 10 (S 10) min followed by air‐drying to yield air‐dried RNS‐COM‐S5 and RNS‐COM‐S10, respectively. Control samples were air‐dried rice flour noodles (ADRN), steamed for 5 or 10 min before air‐drying (ADRN‐S5 and ADRN‐S10). Compared to other air‐dried RNS prepared without steaming, RNS‐COM‐S5 and RNS‐COM‐S10 showed a reduction in cooking time (5.35 min) and cooking loss (7.11%) and increased cooking yield (125%), supposedly due to low gelatinisation enthalpy, while retaining textural and mechanical properties, significantly higher (P < 0.05) than the controls. The scanning electron micrographs showed that all steamed air‐dried noodles also had larger hollows, which could be responsible for the improved cooking qualities. In general, the relative order of starch crystallinity resulting from steaming treatment decreased in all steamed noodles, and RNS‐COM1‐S10 showed the highest order. The treatment of RNS with MTG and GDL yielded air‐dried noodles with a more compact structure. Steaming is necessary to improve the rehydration characteristics of the air‐dried noodles without sacrificing textural and mechanical qualities. [ABSTRACT FROM AUTHOR]

Single component gels (SCG) were formed from gelatine, gellan, maize starch or egg white, while binary composite gel (BCG) and ternary composite gel (TCG) were formed by mixing gelatine or gellan with maize starch and/or egg white. Each type of SCG exhibited distinct textural and microstructure characteristics. Gelatine-SCG was the softest to hold but has the strongest and the most elastic network compared with other SCG. The effects of gelatine or gellan proportions on the textural properties of composite gels were investigated using mixture design experiments. Gelatine and gellan yielded composite gels that showed different textural behaviours and microstructure. All BCG and TCG blends showed antagonistic effects; the composite gels were softer and weaker as compared to the SCG. Gelatine-BCG and TCG were comparatively stronger than those of gellan due to their different gelling mechanisms, in which the former had yielded a denser network structures as compared to the latter. [ABSTRACT FROM AUTHOR]

Statistical analysis of heavy metal concentrations in sediment was studied to understand the interrelationship between different parameters and also to identify probable source component in order to explain the pollution status of selected estuaries. Concentrations of heavy metals (Cu, Zn, Cd, Fe, Pb, Cr, Hg and Mn) were analyzed in sediments from Juru and Jejawi Estuaries in Malaysia with ten sampling points of each estuary. The results of multivariate statistical techniques showed that the two regions have different characteristics in terms of heavy metals selected and indicates that each region receives pollution from different sources. The results also showed that Fe, Mn, Cd, Hg, and Cu are responsible for large spatial variations explaining 51.15% of the total variance, whilst Zn and Pb explain only 18.93 of the total variance. This study illustrates the usefulness of multivariate statistical techniques for evaluation and interpretation of large complex data sets to get better information about the heavy metal concentrations and design of monitoring network. [ABSTRACT FROM AUTHOR]

• Water kefir fermentation improves the digestibility efficacy of casein proteins (CPs). • Added non-nutritive compounds boost the nutritional value of fermented CPs. • Protein quality of CPs can be altered by fermenting microorganisms and their enzymes. • Kefir grains is suitable for natural fermentation due their diverse microorganisms. This study aimed to assess the technique of natural fermentation by applying water kefir to the casein protein. The diverse microorganisms and their enzymes found naturally in the water kefir can influence casein's characteristics. The fermented casein's protein quality (digestibility and secondary protein structure) and composition (total soluble solids and nutritive and non-nutritive substances) were investigated. Our findings revealed that the fermented casein's protein digestibility and total phenolic content increased from 82.46 to 88.60 % and 7.6 to 8.0 mg gallic acid equivalent/100 g, respectively. In addition, their surface charge and hydrophobicity changed from −30.06 to −34.93 mV and 286.9 to 213.7, respectively. Furthermore, the fermented casein's secondary protein components, α-helix (decreased from 13.66 to 8.21 %) and random coil (increased from 16.88 to 19.61 %), were also altered during the fermentation. Based on these findings, the water kefir fermentation approach could be an effective, practical, non-thermal approach for improving casein's protein quality and composition. [ABSTRACT FROM AUTHOR]

• Yellow alkaline noodles were prepared with Hylon VIITM and SemperfrehTM coatings containing salt range 10–30% (w/v). • Increasing salt application reduced optimum cooking time and cooking loss but increased cooking yield. • Increasing salt concentration exhibited higher L* values. • Salt-coatings with 10% salt showed the highest textural, mechanical parameters and sensory evaluation values. • The properties of noodles were influenced by salt from the coatings and, to a lesser extent, the type of coatings used. Zero-salted yellow alkaline noodles (YAN) were immersed in solutions of resistant starch HYLON™ VII (HC) or fruit coating Semperfresh™ (SC) containing a range of salt (NaCl) between 10 and 30% (w/v). The objective was to evaluate the effect of salt-coatings on the textural, handling, cooking, and sensory properties of YAN. Increasing salt in the coatings caused a reduction in optimum cooking time, cooking loss and increase in cooking yield. The mechanical and textural parameters, sensory hardness, springiness and overall sensory acceptability of the salt-coated noodles however decreased with increasing salt application. HC-Na10 and SC-Na10 showed the highest textural and mechanical parameters, sensory hardness and springiness. The differences in the parameters were attributed mainly to the water absorption properties of starch that was affected by salt application. Thus, the quality of salt-coated noodles was dependent mainly on the amounts of salt applied in the coatings rather than on the types of coatings used. [ABSTRACT FROM AUTHOR]

The influences of four types of brewing waters including tap water (TAP), alkaline ionized water (ALK), magnetized water (MAG) and mineral water (MIN), and two brands of commercial green tea (L and T) on quality characteristics of tea infusions were studied. The Oxidation Reduction Potential (ORP) values of the brewing waters was TAP > MAG, MIN > ALK. After brewing, all infusions showed a significant drop (p < 0.05) in pH values. The pH of original brewing waters of ALK (8.64) was the highest as compared to other waters, whereas L-MIN (pH 6.63) and T-MIN (pH 5.82) showed the highest pH values after brewing. Overall, the quality characteristics of green tea infusions were influenced by the brands of tea and the types of brewing water used. MAG was the most superior brewing water in extracting the green tea. Evidenced by total phenolic and flavonoids contents, both L-MAG and T-MAG infusions were superior in extracting antioxidative compounds as compared to other tea infusions. In addition, T-MAG infusion was the least astringent (P < 0.05) and scored the highest (P < 0.05) overall acceptability ( 5.40 ) by sensory panelists., Competing Interests: The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Azhar Mat Easa reports financial support was provided by 10.13039/501100003093Ministry of Higher Education Malaysia. Tan Hui Ling reports financial support was provided by 10.13039/501100004595Universiti Sains Malaysia., (© 2022 The Author(s).)