Nutritional and Rheological Features of Lentil Protein Isolate for Yoghurt-Like Application

Abstract

The substitution of animal protein with proteins of plant origin is a viable way to decrease the negative impact caused by animal husbandry on the environment. Pulse consumption has been widely promoted as a nutritious contribution to protein supplementation. In this study, an emulsion of lentil (Lens culinaris) protein isolate is fermented with lactic acid bacteria (LAB) to manufacture a yoghurt alternative and the techno-functional properties compared to a dairy- and a soy-based product with similar protein contents. The yoghurt-like products are subjected to large and small deformation analysis, quantification of fermentable oligosaccharides, disaccharides, monosaccharides and polyols (FODMAP), water holding capacity tests, protein profile analysis and the gel structure is visualised by confocal laser scanning microscopy (CLSM). The lentil yoghurt alternative shows good water holding capacity, high firmness and consistency values in large deformation analysis, with cohesiveness and viscosity not significantly different from that of dairy yoghurt. The high gel strength and rigidity of the lentil yoghurt gels measured by small deformation analysis is well-reflected in the dense protein matrix in the CLSM graphs. FODMAP content of the lentil yoghurt is very low, making it suitable for consumption by irritable bowel syndrome (IBS) patients. Our results show that lentil protein isolate is an excellent base material for producing a plant-based yoghurt alternative.

Lentil-Based Yogurt Alternatives Fermented with Multifunctional Strains of Lactic Acid Bacteria—Techno-Functional, Microbiological, and Sensory Characteristics

“…The pH and total titratable acidity (TTA) of the samples were measured after inoculation and 12 h fermentation. TTA was measured as described by Boeck et al [ 7 ] using titration with 0.1 M NaOH to a pH of 8.5. The concentration of organic acids in the unfermented emulsions and after 12 h fermentation was evaluated by high performance liquid chromatography (HPLC) as described by Zannini et al [ 14 ].…”

“…To measure the structure formation process of the protein gels, fermentation was performed in the rheometer while small-deformational oscillation analysis was conducted using a method described by Boeck et al [ 7 ], with slight modifications. Briefly, the inoculated milk was transferred to the sanitized, pre-warmed rheometer cup (optimal fermentation temperature, see Table 2 ) and covered with a thin layer of sunflower oil to avoid evaporation.…”

“…The main objective of this research was to characterize the fermentation behavior of LAB strains that had not previously been used for the fermentation of a YA, and investigate the rheological and textural properties of the YA produced. The matrix, an emulsion containing lentil protein isolate has a carbon footprint four times smaller than that of whey protein [ 6 ], and has been previously shown to form yogurt-like gels upon acidification by fermentation with commercial starter cultures [ 7 ]. Commercial plant-based dairy alternatives are often low in protein [ 8 , 9 ]; using plant protein isolates instead of whole plant extracts allows for controlled protein contents that can be equal to or even higher than that of dairy products [ 10 ].…”

Insights into the non‐targeted metabolomic profile, rheological, functional and structural characteristics of rice bran and pulse protein isolates

“…(2021) reported the accumulation of PPs of 95, 63, 46, 28 and 15 kDa in lentil protein isolate. (Boeck et al ., 2021) also reported proteins at 40 kDa and 26–22 kDa might correspond to subunits of the 11S globulin protein primarily known as legumin, one of the storage protein of lentils. Again, GPI showed the major accumulation of PPs of 42, 33, 17 and 15 kDa.…”

LCA as decision support tool in the food and feed sector: evidence from R&D case studies

“…Normalized to the worst-case results per impact category protein isolates is the cultivation of the lentils, thus having ecological burdens, especially in the LCIA categories of Land Use and Aquatic Eutrophication. This first screening encourages to start the development of a lentil-based yogurt alternative, which could pose a viable way towards increasing human lentil consumption in Western countries, produced sustainably, regionally, or even locally (Boeck et al 2021). Considering the similarity of the production process of yogurt from different protein isolates, one could expect that yogurt derived from lentil protein isolate might have a lower ecological burden than dairy-and soy-based products.…”