03640ntm a2200325 i 4500 MY-KuUP 20260526121343.0 t||||fr|||| 000 0 ta 260526t20262026my a|||fr|||| 000 0 eng d THE0010533 (Local) Hardback UMPSA eng UMPSA rda FIST .A33 2026 r Thesis Chan, Ai Chee, author. Influence of glucosamine caramel addition on physicochemical characteristics, and sensory attributes of soy sauce / Chan AI Chee Kuantan, Pahang : UMPSA, 2026 © 2026 xvi, 168 pages : illustrations ; 30 cm. + 1 CD-ROM. rdacontent text rdamedia unmediated rdacarrier volume rda text file PDF Faculty of Industrial Science and Technology Thesis (Master of Science) -- Universiti Malaysia Pahang - 2026 Include bibliographical reference and index Caramel is generally added to soy sauce to enhance its colour, flavour, and antioxidant properties, but it also increases the MRPs which are detrimental to health. Glucosamine caramel offers functional benefits including flavour enhancement, antioxidant activity and reduces formation of harmful compounds compared to conventional caramel. However, most previous glucosamine caramel studies used temperatures less than 70 ºC, leaving higher temperatures unexplored. This research addresses the gap to optimize antioxidant and volatile carbonyl compounds for food applications. Glucosamine caramel was prepared in water, sodium phosphate or sodium acetate solutions at elevated temperatures (80–120 ºC) for 1 and 2 hours. Its physicochemical properties, including pH, browning intensity measured by UV-spectrophotometer, and colour determined using a colourimeter, were evaluated. The antioxidant activity of glucosamine caramel was assessed using ABTS and DPPH assays and reported as Trolox equivalent. The volatile carbonyl compounds were measured using Headspace Solid-phase Microextraction coupled with Gas Chromatography-Mass Spectrometry (HS-SPME GC-MS). Acetate-based caramel prepared at 120 °C for 1 hour was exhibited favorable properties, such as a greenish-blue hue, higher pH, high antioxidant activity (ABTS: 185.79 ± 17.89, DPPH: 124.31 ± 5.74 mM TE/ L), and comparable levels of volatile carbonyl compounds. This caramel was added to soy sauce to make glucosamine caramel soy sauce. It was then compared with commercial soy sauce (control) and glucosamine soy sauce (control) for volatile carbonyls, antioxidant activity and sensory evaluation. For the sensory evaluation, the result demonstrated that glucosamine caramel soy sauce had comparable acceptance to commercial soy sauce (p>0.05) in terms of saltiness, sweetness and overall acceptance. For antioxidant properties, glucosamine caramel soy sauce showed strong antioxidant capacity (DPPH: 262.35 ± 8.66 mM TE/mL, which was comparable to that of commercial soy sauce: 285.20 ± 39.87 mM TE/mL, p>0.05). Analysis of volatile compounds showed a higher level of diacetyl (74.53 ± 4.27 ppb, p<0.05) in glucosamine caramel soy sauce, which is related to enhance buttery notes. This research introduced glucosamine caramel as a functional alternative ingredient for soy sauce products, potentially improving antioxidant properties, flavour and comparable sensory attributes in soy sauce. Faculty of Industrial Science and Technology Dissertations Universities and colleges Dissertations lcc THESIS 0 0 lcc 0 0 10000 10000 2026-05-26 0 FIST .A33 2026 r Thesis T000005025 2026-05-26 12:14:08 2026-05-26 RESTRICT 0 0 lcc 0 1 6 10000 10000 2026-05-26 0 CD14014 T000005026 2026-05-26 12:15:02 2026-05-26 RESTRICT 104897 104903