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The Maillard reaction during the production of brown sugar is critical to the color, flavor and functional characteristics of brown sugar, but it also produces substances potentially harmful to human health such as glyoxal (GO), methylglyoxal (MGO), 3-deoxyglucosone (3-DG), 5-hydroxymethylfurfural (5-HMF), and acrylamide. This paper introduces the Maillard reaction at the key stages of the brown sugar production process, its influential factors, its possible harmful products and their effects on human health, and it puts forward some suggestions for controlling the production of harmful products from Maillard reaction during brown sugar production in order to provide a theoretical reference for improving the safety of brown sugar for consumption.

BACKGROUND: The present study investigates the physical, chemical, and antibacterial properties of water‐soluble chitosan derivatives. Preparation of the water‐soluble chitosan derivatives was performed by the Maillard reaction (MR) between chitosan [with the degree of deacetylation (DD) being 50%, 70%, and 90%] and mannose. No organic reagent was used in the process. Systematic evaluations of the effects of chitosan DD on the reaction extent, the structure, the composition, as well as the physicochemical properties, antioxidant properties, and bacterial inhibitory properties of the finished chitosan–mannose MR products (Mc‐mrps), were carried out. RESULTS: Based on the experimental data obtained from Fourier transform infrared spectroscopy, thermogravimetric analysis, X‐ray diffraction, Pyrolysis‐gas chromatography‐mass spectrometry analysis, and 1H‐NMR, the Mc‐mrps formed from chitosan with different DDs had different structures and components. An increase in the DD of chitosan led to a significant increase in the degree of reaction, color difference (△E), and solubility (P < 0.05). The zeta potential and particle size of the Mc‐mrps were also influenced by the DD of chitosan. Additionally, the antimicrobial action against Gram‐positive (Staphylococcus aureus and Bacillus subtilis) and Gram‐negative bacteria (Escherichia coli and Salmonella typhimurium), as well as antioxidant activity, were enhanced by the incorporation of mannose. This was also achieved by the increase of the DD of chitosan. CONCLUSION: The results of the present study suggest that chitosan was derived with mannose to yield a novel, water‐soluble polysaccharide with better antioxidant and antimicrobial activities. The DD of chitosan had a significant effect on the properties of the Mc‐mrp, which can serve as a reference point for the subsequent preparation and application of such derivatives. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

With the development of the market for flavoured foods and functional beverages in China, flavoured syrup with specific nutrition and health benefits are being used to meet the demand for flavored beverages. However, at present, flavored syrups are mainly produced by thermal concentration technologies, which can easily lead to the loss of heat-sensitive aromatic substances. Accordingly, in this study, jasmine flowers and yellow rock sugar were used as the raw materials to prepare jasmine flower flavor syrup via ultrasonic-assisted low-temperature solid osmotic dehydration (USOD). The optimum conditions obtained by single-factor experiments were: the amount of yellow rock sugar was 120% of that of jasmine (m/m), sugar size as 6~20 mesh, osmosis time as 168 h and ultrasonic time as 120 min. Under these conditions, the yield of the flavoured syrup was 41.40%, the contents of total phenolics and total flavonoids were 175.18 mg GAE/kg dw and 187.92 mg RE/kg dw, respectively, and the DPPH radical scavenging capacity of the flavored syrup was 313.55 mg Trolox/kg dw;Most flavour compounds of jasmine flower were effectively extracted, especially the alcohols, with linalool being 37.94%~46.06%, followed by benzyl alcohol (20.80%~23.90%), indicating that the SOD process had a significant effect on the extraction of flavor compounds. Therefore, the yield of flavored syrup was effectively improved and the flavor components and nutrients of jasmine flowers were retained in this study. This study lays a theoretical foundation for the development and utilization of flavored syrup. [ABSTRACT FROM AUTHOR]

In this study, a novel polyethyleneimine (PEI) modified MOF-derived carbon adsorbent (PEI@MDC) was proposed, which exhibited significant adsorption capacity for Congo Red (CR) in aqueous solutions. FT-IR and XPS results showed that PEI was successfully grafted onto MDC, increasing the content of amine groups on the surface of MDC. The adsorption process conformed to the Langmuir isotherm adsorption model and pseudo-second-order kinetic equation, indicating that the adsorption of CR on PEI@MDC was covered by a single layer, and the adsorption process was controlled by chemical processes. According to the Langmuir model, the maximum adsorption capacity at 30 °C was 1723.86 mg g -1 . Hydrogen bonding and electrostatic interactions between CR and PEI@MDC surface functional groups were the main mechanisms controlling the adsorption process. After five adsorption-desorption cycles, PEI@MDC still showed a high adsorption capacity for CR, indicating that the adsorbent had an excellent regeneration ability., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (This journal is © The Royal Society of Chemistry.)