The effect of brewer’s spent grain melanoidins on the formation of Maillard reaction products in food model systems

Abstract

The Maillard reaction (MR) plays a critical role in determining the final quality of foods and is a key focus in food science research. Numerous studies have explored various strategies that have the common objectives of reducing the formation of potentially toxic compounds, enhancing the formation of desired molecules, and improving sensory attributes.

This thesis introduces the use of melanoidins extracted from brewer’s spent grain, a widely available natural by-product of the brewing industry and a valuable source of functional ingredients, to control the extent of the MR in foods.

Chapter 2 addressed the effect of brewer’s spent grain melanoidins (BSGM) on α-dicarbonyl compounds (DCs) in a BSGM/DC model system. Brewer's spent grain melanoidins (4 mg/mL) quenched over 95% of glyoxal (GO) and methylglyoxal (MGO), and more than 80% of 2,3-butanedione after a 7-day incubation at 37 °C. This was attributed to the hydroxyalkylation reaction, as determined by liquid chromatography highresolution tandem mass spectrometry experiments.

In Chapter 3, BSGM were evaluated for their antiglycative effects in lactose-hydrolysed milk during simulated UHT treatment and subsequent storage at 50 °C for up to two months. Results indicated that IR-BSGM (10 mg/mL) (185 °C for 60 min) effectively reduced the formation of 3-DG, HMF furosine, CML, and MG-H1 by about 30% during UHT treatment. Additionally, the increase rate of these compounds during storage was 25-40% lower in the presence of IR-BSGM compared to the control.

In Chapter 4, The ability of BSGM to reduce the accumulation of DCs was investigated, aiming to control the formation of dietary advanced glycation end-products during accelerated shelf life at 35 °C. The results showed that brewer’s spent grain melanoidins effectively targeted the reactivity of MGO and GO, leading to reductions of CML and MG-H1 by up to 27% and 60%, respectively

These findings demonstrate that melanoidins play a crucial role in mitigating the adverse effects of DCs in different food model systems.

Date of Award	4 Nov 2024
Original language	English
Awarding Institution	Abertay University
Supervisor	Alberto Fiore (Supervisor), Keith Sturrock (Supervisor) & Sarah Cottin (Supervisor)