Exploring the Potential of Lupin (Lupinus angustifolius) Flour-Based Ingredients in Developing High Moisture Meat Analogues

Abstract

The rising demand for sustainably and ethically produced alternatives to animal protein-rich foods has driven interest in plant-based meat analogues. This study evaluated the potential of lupin flour (LF), protein isolate (LPI), and their blends with soy protein isolate (SPI) to produce high-moisture meat analogues (HMMAs) through extrusion cooking. Six SPI-LF-LPI blends, with protein contents ranging from 64.5% to 80.5%, were extruded under three feed moisture contents (FMC) of 60%, 65%, and 70%. Increasing LF content affected the textural attributes of the HMMAs, reducing their hardness, chewiness, and gumminess. The peak force to cut the HMMAs in longitudinal and transverse directions ranged from 3.3 to 10 N, with the softest textures observed for blends containing relatively higher LF and LPI and at the higher FMC level of 70%. In vitro protein digestibility of the HMMAs improved with increasing FMC, reaching a maximum proteolysis degree of 51.5% for the blend containing 55% SPI and 45% LF produced at 70% FMC. Although extrusion reduced the antioxidant capacity of the HMMAs compared to their raw counterparts, the antioxidant capacity of the HMMAs increased as the FMC level increased. These findings highlight the feasibility of using lupin ingredients to produce nutritionally rich and texturally appealing plant-based meat analogues when extrusion conditions are fine-tuned.

Keywords: extrusion cooking; lupin protein; meat alternatives; protein digestibility; soy protein; sustainable food systems.

FIGURE 1

Particle size distribution of the raw materials. SPI: soy protein isolate, LPI: lupin protein isolate, LF: lupin flour.

FIGURE 2

Cutting force on (a) longitudinal cutting force, (b) transverse cutting force, and (c) degree of texturization of extrudates produced by different formulas, and different moisture contents treatments. Errors bars represent ± standard deviation (n = 9). Different letters on bars in each sub‐figure reflect significant differences (p < 0.05).

FIGURE 3

Visual appearance of SPI‐LF and SPI‐LF‐LPI high‐moisture meat analogues. SPI: soy protein isolate, LF: lupin flour, LPI: lupin protein isolate.

FIGURE 4

Antioxidant capacity of raw blends (a and b) and HMMAs (c and d) before () and after () digestion assessed by ABTS•+ and ORAC‐FL assay. Error bars represent ± standard deviation (n = 3). Values assigned with different letters are significantly different (p < 0.05).