Development of fish analogues with algae

: innovation and characterization

Abstract

The growing need for alternatives to marine-derived products has driven the development of two fish analogues: one inspired by sardines and the other by salmon pâté. This choice was made based on their popularity in Portugal, where sardines are culturally iconic and salmon pâté is widely consumed. The primary aim was to create products that closely resemble the nutritional and sensory attributes of their conventional counterparts, with a focus on the use of algae and plant-based protein, particularly pea protein. Ingredients—such as algae and hydrocolloids—were selected based on functionality tests, and the formulations were optimised in terms of texture, flavour, and appearance. The prototypes were characterised for pH, water activity, texture, and lipid profile. The sardine analogue (SA) exhibited a firm and cohesive texture (hardness: 348 g; cohesiveness: 27%), while the salmon spread analogue (SSA) demonstrated good spreadability (adhesion work: −192 g·s). Sensory acceptance of the SA was assessed by 21 participants using a Just-About-Right (JAR) and a hedonic scale, yielding average ratings close to the ideal (3) for flavour (3.1), freshness (3.0), marine aroma (3.05), and texture (2.62). The overall appreciation scored 6.5 out of 9 points. From a nutritional standpoint, both products are eligible for nutritional claims. The SA provides 18 g of protein per 100 g and the SSA 12 g/100 g, supporting the claim "source of protein". Both are also sources of dietary fibre and iodine, and their omega-3 fatty acid contents meet the criteria for the "rich in omega-3" claim, with SA containing 591 mg and SSA 1114 mg, both well above the regulatory threshold. Life Cycle Assessment (LCA) revealed that environmental impacts varied depending on the category analysed. Both analogues showed advantages over their conventional counterparts in terms of CO₂ emissions and land use, although they exhibited higher impacts in other categories of environmental impact. It is concluded that it is feasible to develop seafood analogues that are both sensorially acceptable and nutritionally balanced. While their overall environmental footprint may not be lower than that of conventional products, these analogues contribute to more diverse diets and help avoid the direct degradation of marine ecosystems.

Date of Award	24 Jul 2025
Original language	English
Awarding Institution	Universidade Católica Portuguesa
Supervisor	Dalila da Assunção Maia Vieira (Supervisor)