Effects of 0–12% soy proteins (four texturized and one isolate) on a lean hybrid meat system: cooking loss, texture, dynamic rheology, microstructure, and T2 NMR
Weilun Lin, Shai Barbut
Abstract
• SPI and four TSPs were evaluated in a lean meat system. • Increasing soy protein inclusion decreased cooking loss and increased hardness. • SPI increased the final storage modulus G'. • TSPs reduced the T 2 NMR relaxation time more than SPI. • Small-size TSP caused discontinuities in the meat matrix at 12 % inclusion. Meat and plant hybrid products have recently emerged as part of the global plant-forward movement. Soy proteins have been used at low levels (2–3 %), in meat products since the 1960s, mainly to enhance yield and sensory characteristics. This study assessed the structure-function relationship in products containing 0–12 % soy protein isolate (SPI) and four texturized soy proteins (TSPs: TA, TB, TC, and TD). Soy proteins significantly reduced cooking loss and increased hardness compared to the control (CL, no soy), with these effects intensifying as inclusion levels increased. At 12 %, TD resulted in lower hardness than the other soy proteins. Dynamic rheology revealed that at 6% inclusion, SPI increased the final storage modulus (G') compared to the CL, whereas TA, TB, and TC decreased it. The TD treatment exhibited a final G' similar to CL. Micrographs showed that 12 % TB (smallest texturized soy particles) caused discontinuity in the meat matrix, while TD (largest particles) confined meat components within its structure. T 2 NMR profiles revealed that all soy proteins restricted the water mobility of the meat batters, with TSPs showing a more pronounced effect than SPI. The relative order of T 21 values of cooked meat batters aligns with the cooking loss results. Overall, TSPs showed superior water binding to SPI. In this study, the larger size of TSPs likely had a favorable effect on their binding to the meat matrix at the high inclusion level (12 %). These findings provide insights into the selection of soy proteins for hybrid meat production.