Alternativas alimentares de origem vegetal

: desenvolvimento de um análogo vegetal ao ovo líquido

Abstract

Vegetarian diets are a viable alternative to ensure a sustainable future, as they use fewer natural resources and have a lower environmental impact than those based on animal products. The aim of this project was to develop a vegetable alternative to liquid egg based on a sugar-free organic soy drink. Specific ingredients were added so that the final formulation respected the original as much as possible the most relevant nutritional component, the organoleptic profile. The functional behaviour of eggs scrambled in a skillet was also mimicked. Methylcellulose and k-carrageenan were used as gelling agents, starch as a texturizing agent, nigari for the coagulation of heat-denatured soy proteins and soy lecithin to allow for emulsion. Also, by adding sunflower oil to the matrix, a lipid component similar to that found in chicken eggs was achieved. The seasoning mix contained Himalayan black salt, nutritional yeast, onion powder, garlic powder and sweet pepper, elevating the flavour profile of the product. In order to test the effect of HPP (High-pressure processing) processing by submitting the analogue to 550 MPa for 3 min at approximately 20 ºC. The microbiological quality and shelf life of the analogue when stored at 4ºC for 45 and 15 days was evaluated in two different experiments, respectively. Considering the total mesophilic count, which reached values > 7.0 Log (cfu/mL) at 30 days of storage, the shelf life of the liquid egg analogue in the first experiment was estimated between 15 and 30 days, however in the second experiment this was reduced to approximately 7 to 15 days. The nutritional profile of the analogue was detailed by proximate analysis, with a final estimated energy value of 85 kcal per 100 g of product, total fat content of 6.2%, containing 1.0% of saturated fatty acids, hydrates content of total carbon 3.5%, of which 0.8% correspond to simple sugars and a protein content of 4.0%. Rheological tests revealed that the viscosity of the vegetable analogue to the liquid egg increased between 7 and 15 days of storage, up to a maximum of about 150% of complex viscosity and 200% of instantaneous viscosity. In summary, the developed analogue has an organoleptic profile resembling that of chicken eggs, however barriers such as low protein content and reduced microbiological stability will have to be overcome to achieve a capable vegetarian alternative.

Date of Award	24 Jan 2022
Original language	Portuguese
Awarding Institution	Universidade Católica Portuguesa
Supervisor	Ana Maria Gomes (Supervisor) & João Diogo André Peça (Supervisor)