Comparison of protein quality and digestibility between plant-based and meat-based burgers

Protein transition: focus on protein quality in sustainable alternative sources

The current consumption trends, combined with the expected demographic growth in the coming years, call for a protein transition, i.e., the partial substitution of animal protein-rich foods with foods rich in proteins produced in a more sustainable way. Here, we have discussed some of the most common and promising protein sources alternative to animal proteins, namely: legumes, insects, and microorganisms (including microalgae and fungi). The primary objective was to assess their nutritional quality through the collection of digestible indispensable amino acid score (DIAAS) values available in the scientific literature. Protein digestibility corrected amino acid score (PDCAAS) values have been used where DIAAS values were not available. The ecological impact of each protein source, its nutritional quality and the potential applications in traditional foods or novel food concepts like meat analogues are also discussed. The data collected show that DIAAS values for animal proteins are higher than all the other protein sources. Soybean proteins, mycoproteins and proteins of some insects present relatively high DIAAS (or PDCAAS) values and must be considered proteins of good quality. This review also highlights the lack of DIAAS values for many potentially promising protein sources and the variability induced by the way the proteins are processed.

Nutrition classification schemes for plant-based meat analogues: Drivers to assess nutritional quality and identity profile

Changes in dietary patterns promoted by the emergence of alternative food systems are becoming increasingly common. The decrease in the consumption of animal-derived products promoted exponential growth in plant-based product demand and, consequently, the availability of several meat analogues for this consumer market. Plant-based meat analogues (PBMAs) were developed to mimic the physical and sensory characteristics of meats and their derivatives. Therefore, the composition of these products has been studied in some countries as an attempt to evaluate their nutritional quality in comparison with that of traditional meat products. The main aim of this study was to employ different Nutrition Classification Schemes (NCSs) to assess the nutritional quality of plant-based meat and to discuss the application of one or more NCSs in defining the identity and quality profile of these foods. Five NCSs were used: three nutrient-based (Nutri-Score; Nutrient Profiling Model (NPM) from Brazil; NPM from PAHO); one food-based (NOVA classification); and one hybrid (Plant-Based Nutrient Profile Model). The nutritional composition and ingredients were collected from labels of 349 PBMAs; 117 were classified as burgers, and 182 products employed soy as the main protein ingredient. The use of different NCSs is strategic for PBMAs' nutritional quality evaluation, and the Nutri-Score was able to show the effectiveness of differentiating products as having poor nutritional quality. In this way, the employment of NPM from Brazil is recommended as a driver for PBMAs choices, especially due to the excellent agreement between the Nutri-Score and NPM from Brazil for burgers.

Formulation of new sourdough bread prototypes fortified with non-compliant chickpea and pea residues

Purpose

Nowadays, the promotion of a circular economy is fundamental to reduce food losses and waste. In this context, the possibility of using food supply chains non-compliant residues emerges. Much interest has been directed toward legume residues, in general and, in particular, to the possibility of combining different plant-matrices to improve nutritional profile, providing high-quality products.

Methods

Five different formulations of breads, with a combination of seeds and cereals, were fortified with chickpea and pea protein concentrates. Samples were analyzed and compared with their relative control recipe to determine differences in composition, actual protein quality and integrity, and protein digestibility (performed with the INFOGEST method).

Results

Samples showed a clear improvement in the nutritional profile with higher values of proteins, from averagely 12.9 (control breads) to 29.6% (fortified breads) (17.7-24.7 g/100 g of dry matter respectively), and an improvement in amino acidic profile, with a better balancing of essential amino acids (lysine and sulfur amino acid contents), without affecting protein integrity. Regarding in vitro gastro-intestinal digestibility, sample C (19% chickpea proteins) showed the best results, having a comparable protein digestibility to its control bread-48.8 ± 1.1% versus 51.7 ± 2.3%, respectively.

Conclusion

The results showed how the fortification with chickpea and/or pea protein concentrate improved the nutritional profile of bread. These prototypes seem to be a valid strategy to also increase the introduction of high biological value proteins. Furthermore, the not-expected lower digestibility suggested the possible presence of residual anti-nutritional factors in the protein concentrates interfering with protein digestibility. Therefore, it seems of fundamental importance to further investigate these aspects.

In vitro digestion of beef and vegan burgers cooked by microwave technology: Effects on protein and lipid fractions

Commercial beef burgers and vegan analogues were purchased and, after a microwave treatment, they were submitted to an in vitro digestion (INFOGEST). Vegan cooked burgers showed similar protein content (16-17 %) but lower amounts of total peptides than beef burgers. The protein digestibility was higher in beef burgers. Peptide amounts increased during in vitro digestion, reaching similar amounts in both types of products in the micellar phase (bioaccessible fraction). The fat content in cooked vegan burgers was significantly lower than in beef burgers (16.7 and 21.2 %, respectively), with a higher amount of PUFAs and being the lipolysis activity, measure by FFA, less intense both after cooking and after the gastrointestinal process. Both types of cooked samples showed high carbonyl amounts (34.18 and 25.51 nmol/mg protein in beef and vegan samples, respectively), that decreased during in vitro digestion. On the contrary, lipid oxidation increased during gastrointestinal digestion, particularly in vegan samples. The antioxidant capacity (ABTS and DPPH) showed higher values for vegan products in cooked samples, but significantly decreased during digestion, reaching similar values for both types of products.

Substitution of One Meat-Based Meal With Vegetarian and Vegan Alternatives Generates Lower Ammonia and Alters Metabolites in Cirrhosis: A Randomized Clinical Trial

INTRODUCTION

Diet can affect ammoniagenesis in cirrhosis and hepatic encephalopathy (HE), but the impact of dietary preferences on metabolomics in cirrhosis is unclear. As most Western populations follow meat-based diets, we aimed to determine the impact of substituting a single meat-based meal with an equal protein-containing vegan/vegetarian alternative on ammonia and metabolomics in outpatients with cirrhosis on a meat-based diet.

METHODS

Outpatients with cirrhosis with and without prior HE on a stable Western meat-based diet were randomized 1:1:1 into 3 groups. Patients were given a burger with 20 g protein of meat, vegan, or vegetarian. Blood for metabolomics via liquid chromatography-mass spectrometry and ammonia was drawn at baseline and hourly for 3 hours after meal while patients under observation. Stool microbiome characteristics, changes in ammonia, and metabolomics were compared between/within groups.

RESULTS

Stool microbiome composition was similar at baseline. Serum ammonia increased from baseline in the meat group but not the vegetarian or vegan group. Metabolites of branched chain and acylcarnitines decreased in the meat group compared with the non-meat groups. Alterations in lipid profile (higher sphingomyelins and lower lysophospholipids) were noted in the meat group when compared with the vegan and vegetarian groups.

DISCUSSION

Substitution of a single meat-based meal with a non-meat alternatives results in lower ammoniagenesis and altered serum metabolomics centered on branched-chain amino acids, acylcarnitines, lysophospholipids, and sphingomyelins in patients with cirrhosis regardless of HE or stool microbiome. Intermittent meat substitution with vegan or vegetarian alternatives could be helpful in reducing ammonia generation in cirrhosis.

Assessment of Protein Quality and Digestibility in Plant-Based Meat Analogues

In this first work, commercial steak-like (n = 3) and cured meat (n = 3) analogues with different legume and cereal formulations were studied and compared to their animal-based (n = 3) counterparts. Plant-based products showed lower protein content than meat controls but a good amino acidic profile even though the sum of essential amino acids of plant-cured meats does not fulfill the requirements set by the Food and Agriculture Organization for children. A comparable release of soluble proteins and peptides in the digestates after in vitro digestion was observed in meat analogues as meat products, whereas the digestibility of proteins was lower in plant-based steaks and higher in plant-based cured meats than their counterparts. The overall protein quality and digestibility of products are related to both the use of good blending of protein sources and processes applied to produce them. An adequate substitution of meat with its analogues depends mostly on the quality of raw materials used, which should be communicated to consumers.

Does livestock ownership predict animal-source food consumption frequency among children aged 6-24 months and their mothers in the rural Dale district, southern Ethiopia?

Background

Animal-source foods are food items that come from animals. Animal-source foods provide a variety of micronutrients that plant-source foods cannot provide to the same extent and without extra precaution. Milk, eggs, poultry, flesh meat and fish are animal-source foods mainly used in Ethiopia. Low animal-source food consumption among children and mothers is a great concern in many low-income settings. This study aimed to describe animal-source food consumption frequencies among children aged 6-24 months and their mothers in rural southern Ethiopia where livestock farming is very common. We also analysed the association between livestock ownership and animal-source food consumption among children and mothers.

Methods

A community-based cross-sectional study was conducted among 851 randomly selected households with child-mother pairs from August to November 2018. The study was conducted in the rural Dale District, southern Ethiopia. Structured and pre-tested questionnaires were used to collect data on mother and child information, livestock ownership, and animal-source foods consumption frequencies. Ordinal logistic regression analysis was used to describe associations between animal-source foods consumption and livestock ownership.

Result

Nearly, three-quarters (74.1%) of the households owned cows, and a quarter (25%) had goats or sheep. Dairy, egg and meat consumption among children during the past month was 91.8%, 83.0% and 26.2%, respectively. Likewise, the consumption of dairy, eggs and meat among mothers was 96.0%, 49.5% and 34.0%, respectively. The percentage of children who had not consumed any animal-source foods during the month prior to our survey was 6.6%, and the figure was 2.2% for the mothers. Dairy consumption was 1.8 times higher among children (aOR = 1.8, 95% CI [1.3-2.5]) and 3.0 times higher among mothers (aOR = 3.0, 95% CI [2.2-4.2]) in households that kept cows than in households without cows. The egg consumption frequency was positively associated with hen and goat/sheep ownership for both children and mothers. Meat consumption frequency among children was negatively associated with cow ownership (aOR = 0.66, 95% CI [0.45-0.95]); however, cow ownership was not associated with meat consumption among mothers.

Conclusion

Dairy products were common animal-source foods consumed by young children and mothers in the study area. However, meat consumption was low among children and mothers. Strategies like promoting the keeping of goats/sheep and hens to improve complementary feeding and mothers' nutrition are warranted in the study area.