Abstract
Plant-based meat analogues (PBMAs) have become an important category in the food industry, offering a sustainable and ethical alternative to conventional meat. The global demand for PBMAs is driven by increasing vegetarianism, health consciousness, environmental concerns, and animal welfare considerations. Among these PBMAs, plant-based (PB) meat burgers have gained popularity due to their sensory similarity to traditional meat and the familiarity of burgers in modern diets.
However, PB meat burgers face several challenges, including poor texture, flavour, and mouthfeel, lower nutritional quality, highly processed formulations, and concerns regarding clean labelling. To overcome these issues, various strategies, such as the selection of high-quality raw materials, blending different plant protein sources, and adopting innovative processing techniques, are being explored. Additionally, the final cooking method, performed by consumers, plays a crucial role in determining the texture, appearance, sensory attributes, and nutritional properties of PB meat burgers. Despite this, limited research has focused on the impact of different cooking techniques on these burgers. Understanding how cooking methods and durations influence the physicochemical properties of PB meat burgers is essential to filling this knowledge gap.
This thesis investigated the effects of four cooking methods (pan-frying, oven-baking, sous-vide, and microwave) on the physicochemical properties of beef, Beyond, and Impossible burgers. Additionally, the impact of sous-vide cooking at different durations (90, 120, and 150 minutes) was analysed.
The findings highlight that cooking methods significantly influence the appearance, texture, cooking loss, and volatile flavour profile of both beef and PB meat burgers. Among the PB burgers, Beyond Burger exhibited texture characteristics similar to beef across all cooking methods. Conversely, the volatile profile of Impossible Burger resembled to that of beef, while Beyond Burger displayed the most distinct volatile composition.
Among the tested cooking methods, oven-baking appeared to be the most effective, followed by sous-vide, for all burger types. Oven-baking enhanced the visual appeal of PB burgers. It produced a balanced texture and created favourable conditions for the Maillard reaction, contributing to flavour development. In contrast, microwaving was the least favourable cooking method, negatively affecting all physicochemical properties of the burgers. Microwaved burgers exhibited the highest cooking loss and underwent significant degradation in texture and volatile compounds.
Regarding sous-vide cooking duration, 120 minutes appeared to be the optimal time for all burger types. Beyond and Impossible burgers maintained a visual resemblance to beef at all sous-vide durations. Hardness increased with cooking time up to 120 minutes, but at 150 minutes, hardness declined for both PB burgers. A similar trend was observed in most of the volatile compounds, which peaked at 120 minutes before decreasing at 150 minutes, suggesting that prolonged sous-vide cooking may lead to the degradation or loss of key volatile compounds.
In conclusion, this research bridges a knowledge gap regarding PBMAs and their response to different cooking methods. These findings are important in selecting appropriate cooking methods to improve the overall quality of the PB burgers which increases consumer acceptance. Manufacturers can use these findings to improve PB burger formulations and provide cooking recommendations that enhance consumer satisfaction. For consumers, understanding the effects of cooking methods could guide in cooking choices to achieve a desirable eating experience.