Nutritional evaluation of mixed wheat–faba bean pasta in growing rats: impact of protein source and drying temperature on protein digestibility and retention

Abstract

This study aimed to evaluate the nutritional value of pasta enriched with legume or wheat gluten proteins and dried at varying temperature. A total of four isonitrogenous experimental diets were produced using gluten powder/wheat semolina (6/94, g/g) pasta and faba bean flour/wheat semolina (35/65, g/g) pasta dried at either 55°C (GLT and FLT, respectively) or 90°C (FVHT and GVHT, respectively). Experimental diets were fed to ten 1-month-old Wistar rats (body weight=176 (sem 15) g) for 21 d. Growth and nutritional, metabolic and inflammatory markers were measured and compared with an isonitrogenous casein diet (CD). The enrichment with faba bean increased the lysine, threonine and branched amino acids by 97, 23 and 10 %, respectively. Protein utilisation also increased by 75 % (P<0·01) in FLT in comparison to GLT diet, without any effect on the corrected faecal digestibility (P>0·05). Faba bean pasta diets' corrected protein digestibility and utilisation was only 3·5 and 9 %, respectively, lower than the CD. Growth rate, blood composition and muscle weights were not generally different with faba bean pasta diets compared with CD. Corrected protein digestibility was 3 % lower in GVHT than GLT, which may be associated with greater carboxymethyllysine. This study in growing rats clearly indicates improvement in growth performance of rats fed legume-enriched pasta diet compared with rats fed gluten–wheat pasta diet, regardless of pasta drying temperature. This means faba bean flour can be used to improve the protein quality and quantity of pasta.

Anabolic Properties of Mixed Wheat-Legume Pasta Products in Old Rats: Impact on Whole-Body Protein Retention and Skeletal Muscle Protein Synthesis

“…Furthermore, contrary to what was shown with the 35% faba bean pasta [46], here we observed equivalent protein utilization between legume-enriched pasta and casein diets when the legume enrichment level in the pasta increased up to 62-79%. The essential amino acid composition of the legume-enriched pasta used here was closer to casein and to rat needs according to National Research Council [61] than for the 35% faba bean pasta [46]. However, here, the measured net protein utilization was lower in old rats fed casein or legume-enriched pasta than SMP.…”

“…Mixed wheat-legume pasta has a more balanced amino acid composition when compared to wheat protein alone, i.e., gluten-enriched pasta, which could explain the higher protein utilization [46]. Furthermore, contrary to what was shown with the 35% faba bean pasta [46], here we observed equivalent protein utilization between legume-enriched pasta and casein diets when the legume enrichment level in the pasta increased up to 62-79%. The essential amino acid composition of the legume-enriched pasta used here was closer to casein and to rat needs according to National Research Council [61] than for the 35% faba bean pasta [46].…”

“…This contrasts with Löhrke et al [60], who reported a higher urinary nitrogen excretion and increased plasma level of urea in pigs in response to dietary soybean protein isolate when compared to casein. Laleg et al [46] demonstrated that protein utilization increased by 75% in young rats fed wheat pasta enriched with 35% faba bean flour as compared to an isoproteic wheat pasta enriched with gluten, but remained 9% lower than in rats fed casein. Mixed wheat-legume pasta has a more balanced amino acid composition when compared to wheat protein alone, i.e., gluten-enriched pasta, which could explain the higher protein utilization [46].…”

“…Laleg et al [46] demonstrated that protein utilization increased by 75% in young rats fed wheat pasta enriched with 35% faba bean flour as compared to an isoproteic wheat pasta enriched with gluten, but remained 9% lower than in rats fed casein. Mixed wheat-legume pasta has a more balanced amino acid composition when compared to wheat protein alone, i.e., gluten-enriched pasta, which could explain the higher protein utilization [46]. Furthermore, contrary to what was shown with the 35% faba bean pasta [46], here we observed equivalent protein utilization between legume-enriched pasta and casein diets when the legume enrichment level in the pasta increased up to 62-79%.…”

“…Overall, they demonstrated that plant protein blends had greater effect than a single plant protein source. Torres et al [43][44][45], Laleg et al [46], and Giménez et al [47] also demonstrated the beneficial effects of incorporating 10%-35% legume flour in wheat pasta and 30% legume flour in corn pasta on protein digestibility and net protein utilization (NPU) in young rats. However, to our knowledge, the nutritional benefits of such combinations in older individuals has never yet been studied.…”