Seven different in vitro methods to determine the protein digestibility for chickpea proteins were considered and also the application of these methodologies for calculating PDCAAS (protein digestibility-corrected amino acid score), seeking their correlations with the in vivo methodology. In vitro digestibility of raw and heated samples were determined using pepsin-pancreatin hydrolysis, considering soluble nitrogen via Kjeldahl (ppKJ) and hydrolysed peptide linkages using trinitrobenzenesulfonic acid and o-phthaldialdehyde. In vitro digestibility was also determined using trypsin, chymotrypsin and peptidase (3-Enz) or trypsin, chymotrypsin, peptidase and pronase solution (4-Enz). None of the correlations between in vitro and in vivo digestibilities were significant (at p<0.0500), but, strong correlations were observed between PDCAAS calculated by in vitro and in vivo results. PDCAAS-ppKJ, PDCAAS-3-Enz and PDCAAS-4-Enz presented the highest correlations with in vivo method, r=0.9316, 0.9442 and 0.9649 (p<0.0500), respectively. The use of in vitro methods for calculating PDCAAS may be promising and deserves more discussions.

La proteína aislada de arveja es una nueva alternativa de proteína vegetal, libre de alérgenos, lactosa y gluten por lo cual está siendo utilizada como sustituto de otras ingredientes proteicos. El objetivo de esta investigación fue caracterizar física, química, funcional, sensorial y microbiológicamente tres lotes de proteína aislada de arveja (20, 21 y 22), elaborados en dos fases de escalamiento antes de llegar a la fase industrial. Los resultados de proteína (81%), fibra dietética (3.8%), grasa (2.5%) y minerales no presentaron diferencias. Humedad (4.5%) y cenizas mostraron mínimas diferencias pero dentro del rango de variabilidad productiva. La proteína de arveja mostro una calidad proteica media (PDCAAS= 0.61), un perfil de aminoácidos y ácidos grasos diferentes y bajo en omegas 3 y 6 que la proteína de soya. La firmeza y elasticidad en geles (1:3 y 1:4) fueron diferentes significativamente entre lotes 20 y 21. Los lotes 20 y 22 no cumplieron los estándares internos microbiológicos de la compañía pero si los del FDA. La aceptabilidad y preferencia del perfil de sabor del aislado de arveja fue menor al del aislado de soya evaluado en un prototipo de sopa alta en proteína (6g/porción). Las diferentes etapas del proceso de escalamiento no presentaron diferencias significativas químico-funcionales lo cual refleja un buen proceso de escalamiento, sin embargo, se requiere más investigación para mejorar el perfil de sabor y asegurar la calidad microbiológica del ingrediente.

Tese de Doutoramento em Nutrição Clínica, apresentada à Faculdade de Ciências da Nutrição e Alimentação da Universidade do Porto, 2016 | Coorientador Isabel Castanheira - Departamento Alimentação e Nutrição do Instituto Nacional de Saúde Doutor Ricardo Jorge. | O uso de compostos de origem natural no fabrico alimentos destinados a uma alimentação destinada a fins medicinais específicos, otimizando ao máximo as propriedades nutricionais dos alimentos pode constituir uma forma de aumentar a acessibilidade e a palatabilidade destas fórmulas. Neste sentido, os pseudocereais como a quinoa, o amaranto e o trigo-sarraceno, pelo seu valor nutricional e ausência de glúten, são ingredientes a considerar. O principal objetivo desta tese foi avaliar o efeito da maltagem e da confeção (cozedura e cozedura a vapor) no valor nutricional e na bioacessibilidade de nutrientes dos pseudocereais amaranto, quinoa e trigo-sarraceno, com vista à incorporação destes ingredientes em produtos alimentares destinados a fins alimentares específicos. Como termo de comparação foi avaliado o efeito da cozedura no valor nutricional na bioacessibilidade de nutrientes do arroz branco polido (agulha e carolino). Avaliou-se ainda a evolução dos teores em acrilamida na quinoa quando sujeita ao processo de torragem com vista ao desenvolvimento de aromas potencialmente mais apreciados pelos consumidores; e o efeito da granulometria de farinhas de quinoa crua na bioacessibilidade dos seus nutrientes foi também avaliado. Para tal, após um processo de amostragem seletivo das diferentes amostras de arroz e pseudocereais, foram realizados diferentes processamentos culinários e de maltagem. As amostras cruas e sujeitas a processamento foram avaliadas nutricionalmente através da determinação de macronutrientes, aminoácidos, folatos, minerais, oligoelementos e elementos traço e quanto à presença de contaminantes. A retenção dos nutrientes foi maior no amaranto cozido e maltado para os aminoácidos e folatos, respetivamente. Para quinoa foi a cozedura que induziu menores perdas nutricionais, com exceção do aminoácido cisteína e dos folatos. Para o trigo-sarraceno foi a maltagem o processo que produziu menores perdas de aminoácidos e folatos, induzindo, no entanto, maiores perdas de minerais e oligoelementos. Os pseudocereais constituem uma importante reserva de aminoácidos, com PDCAAS próximos de 1,00 e significativamente mais elevados que o arroz polido. Os PDCAAS das proteínas puderam ser ordenados de forma decrescente da seguinte forma: quinoa > trigo sarraceno > amaranto > arroz. Observou-se contudo um decréscimo da qualidade proteica durante a confeção relativamente ao alimento cru. A maltagem preservou a qualidade proteica dos pseudocereais. Os pseudocereais, com destaque para a quinoa, constituem uma fonte importante de folatos altamente bioacessíveis. Nas sementes de amaranto, os valores de ferro, cálcio, potássio e magnésio são geralmente mais elevados do que os encontrados noutros grãos sendo que o seu uso como ingrediente na elaboração de formulações pode ajudará a melhorar o perfil mineral destes produtos. A fibra dietética é outra componente de relevância fisiológica encontrada em quantidades abundantes nas sementes dos pseudocereais. Verificou-se ainda que durante a torragem da quinoa ocorre a síntese de acrilamida atingindo altos teores indesejáveis No que diz respeito à bioacessibilidade no amaranto foi a cozedura tradicional que induz o maior aumento da bioacessibilidade para todos os nutrientes estudados. Na quinoa foi a maltagem que produz esse efeito em maior percentagem. No trigo-sarraceno, a cozedura, quer tradicional quer a vapor são as formas de processamento mais eficazes para aumentar a bioacessibilidade das proteínas, folatos e minerais. De acordo com os resultados obtidos os pseudocereais constituem uma fonte de muitos aminoácidos, folatos e minerais altamente bioacessíveis, contendo teores substancialmente mais elevados do que o arroz. Verificou-se ainda que uma menor granulometria das farinhas de quinoa aumentou significativamente a bioacessibilidade dos seus nutrientes. O elevado valor e bioacessibilidade dos nutrientes dos pseudocereais, em especial após os processamentos, fazem com que estes produtos representem uma importante opção como ingredientes integrados em produtos dietéticos destinados a fins medicinais específicos, incluindo as fórmulas entéricas ricas em fibra e produtos isentos de glúten. | The use of naturally occurring compounds in the manufacture of medical foods, by optimizing the nutritional properties of food, can be a way to increase the accessibility and palatability of these formulas. The use of pseudocereals such as quinoa, amaranth, buckwheat and rice may be, for their nutritional value, and gluten free properties, a valid alternative. The main objective of this thesis was to evaluate the effect of malting and confection (boiling and steaming) on the nutritional value and bioaccessibility of nutrients from pseudocereals amaranth, quinoa and buckwheat, in order to incorporating these ingredients in foods for specific dietary purposes. For comparative purposes, the effects of cooking on the nutritional value in the bioaccessibility in nutrients of polished white rice (Indica and Japonica) were also evaluated. Levels of acrylamide in the quinoa when subjected to roasting process, for the development of potentially more appreciated aromas; and the effect of particle size of raw quinoa flour in the bioaccessibility of nutrients was also evaluated. After a selective sampling plan of samples, rice and pseudocereals were submitted to various culinary and malting processes. The raw and processed samples were nutritionally evaluated through the determination of macronutrients, amino acids, folates, minerals and trace elements as also for the presence of contaminants. The nutrient retention was higher in baked amaranth and malted for amino acids and folate, respectively. For quinoa, is the cooking method that induced lower nutrient losses, with the exception of cysteine and folates. For buckwheat was malting process that produced the lowest losses of amino acids and folates, inducing, however, greater losses of minerals and trace elements. The pseudocereals constitute an important reserve of amino acids, with PDCAAS close to 1.00 and significantly higher than the polished rice. The PDCAAS of proteins could be sorted in descending order as follows: quinoa> buckwheat> Amaranth> rice. There was however a decrease in protein quality during quilting relative to the raw food. The malting preserved the protein quality of pseudocereals. The pseudocereals, especially quinoa are an important source of highly bioacessible folates. In amaranth seeds, iron values, calcium, potassium and magnesium are generally higher than those found in other grains and their use as an ingredient in the preparation of formulations can help improve the mineral profile of these products. Dietary fiber is another physiological relevance component found in abundant quantities in the seeds of pseudocereals. It was also found that during the roasting of quinoa occurs acrylamide synthesis reaching undesirable high levels. Regarding the bioaccessibility in amaranth was the traditional cooking that induces a greater increase in bioaccessibility for all nutrients studied. On the malting was quinoa which produces this effect at higher percentage. In buckwheat, cooking, both using traditional and steam are the most effective ways to increase processing bioaccessibility of proteins, folates and minerals. According to the results obtained pseudocereals are a source of many amino acids, folates and highly bioaccessible minerals containing substantially higher levels than rice. It was also found that a smaller particle size of the quinoa flour significantly increased their bioaccessibility of nutrients. The high value and bioaccessibility of nutrients from pseudocereals, especially after processing, make these products an important option as ingredients in dietary products for special medical purposes, including enteral formulas fiber containing and gluten-free products. | N/A

La proteína aislada de arveja es una nueva alternativa de proteína vegetal, libre de alérgenos, lactosa y gluten por lo cual está siendo utilizada como sustituto de otras ingredientes proteicos. El objetivo de esta investigación fue caracterizar física, química, funcional, sensorial y microbiológicamente tres lotes de proteína aislada de arveja (20, 21 y 22), elaborados en dos fases de escalamiento antes de llegar a la fase industrial. Los resultados de proteína (81%), fibra dietética (3.8%), grasa (2.5%) y minerales no presentaron diferencias. Humedad (4.5%) y cenizas mostraron mínimas diferencias pero dentro del rango de variabilidad productiva. La proteína de arveja mostro una calidad proteica media (PDCAAS= 0.61), un perfil de aminoácidos y ácidos grasos diferentes y bajo en omegas 3 y 6 que la proteína de soya. La firmeza y elasticidad en geles (1:3 y 1:4) fueron diferentes significativamente entre lotes 20 y 21. Los lotes 20 y 22 no cumplieron los estándares internos microbiológicos de la compañía pero si los del FDA. La aceptabilidad y preferencia del perfil de sabor del aislado de arveja fue menor al del aislado de soya evaluado en un prototipo de sopa alta en proteína (6g/porción). Las diferentes etapas del proceso de escalamiento no presentaron diferencias significativas químico-funcionales lo cual refleja un buen proceso de escalamiento, sin embargo, se requiere más investigación para mejorar el perfil de sabor y asegurar la calidad microbiológica del ingrediente.

Better assessment of the quality of dietary protein sources allows their better use. The FAO has recommended replacing the protein digestibility–corrected amino acid score (PDCAAS) with the digestible indispensable amino acid score (DIAAS) in which ileal amino acid digestibility values obtained in pigs are used. A study on growing pigs was conducted to determine true fecal protein digestibility and standardized ileal amino acid digestibility of rice, rye and barley. Using these values the PDCAAS and DIAAS were calculated and compared. A total of 18 gilts with a T-cannula inserted in the terminal ileum were allotted to 3 diets - six replicate pigs per diet. Three semi-purified diets were formulated to contain the tested cereal grains (rice, rye, barley) as the sole nitrogen source and with an indigestible marker (chromic oxide). Each experimental period comprised of a 7-d adaptation followed by 1-d (24 h) collection of feces and ileal digesta. All tested parameters were greatest in rice. Significant differences (P < 0.05) in both protein and amino acids digestibility among the rice and other cereals (rye and barley) were found. True fecal protein digestibility was significantly greater than the mean ileal amino acids digestibility for all tested samples, thus suggesting an overestimation of protein quality determined by means of PDCAAS. Calculated PDCAAS values for rice, rye and barley (81, 65 and 61%) were generally higher than a DIAAS values (79, 56 and 55%), especially for the poorer quality proteins - rye and barley in comparison with rice.

WOS:000375349500001 | International audience | The Protein Digestibility Corrected Amino Acid Score (PDCAAS) has been adopted for assessing protein quality in human foods since 1991, and the shortcomings of using the PDCAAS have been recognized since its adoption. The 2011 FAO Expert Consultation recognized that the Digestible Indispensable Amino Acid Score (DIAAS) was superior to the PDCAAS for determining protein quality. However, there were insufficient human data on amino acid digestibility before adopting the DIAAS. More human data were needed before DIAAS could be implemented. In 2014, FAO convened an expert working group to propose and agree on research protocols using both human-based assays and animal models to study ileal amino acid digestibility (metabolic availability) of human foods. The working group identified 5 research protocols for further research and development. A robust database of protein digestibility of foods commonly consumed worldwide, including those consumed in low-income countries, is needed for an informed decision on adopting the DIAAS. A review on the impacts of using the DIAAS on public health policies is necessary. It would be advantageous to have a global coordinating effort to advance research and data collection. Collaboration with international and national agriculture institutes is desirable. Opportunities should be provided for young researchers, particularly those from developing countries, to engage in protein-quality research for sustainable implementation of DIAAS. To conclude, the DIAAS is a conceptually preferable method competed with the PDCAAS for protein and amino acid quality evaluation. However, the complete value of the DIAAS and its impact on public health nutrition cannot be realized until there are sufficient accumulated ileal amino acid digestibility data on human foods that are consumed in different nutritional and environmental conditions, measured by competent authorities. A future meeting may be needed to evaluate the size and quality of the data set and to determine the timeline for full adoption and implementation of the DIAAS.

Protein quality refers to the amounts and ratios of essential amino acids in a food. Two methods most commonly used for determining protein quality are the protein digestibility-corrected amino acid score (PDCAAS) and the digestible indispensible amino acid score (DIAAS). To use existing literature to compare different amino acid profiles and PDCAAS and DIAAS scores in individuals with acute inflammation and to assess their relationship with weight gain in children with severe acute malnourished (SAM). A series stable isotope studies were previously conducted in children with SAM and acute infection, and these data were reviewed with respect to protein synthesis. Eleven published treatment trials for SAM with different therapeutic foods were analyzed to examine the relationship between protein quality scores with weight gain (g/kg/d). Protein scores were calculated with the PDCAAS and DIAAS amino acid reference patterns. A DIAAS score adjusted for the higher weight gain expected in malnourished children was also used. Bivariate correlation analysis was used to examine this relationship. The protein kinetic data supported the hypothesis that a balance of amino acids that matches the composition of acute-phase proteins maximizes amino acid synthesis. Protein quality scores were highly correlated with the rate of weight gain in recovery from SAM, and the DIAAS scoring system adjusted for the higher expected weight gain had the strongest correlation with the observed weight gain. Protein quality scores must account for physiologic status so that they better match with needs and thus better promote health.

In this study, the nutritional quality of pasta-like product (spaghetti-type), made with corn (Zea mays) flour enriched with 30% broad bean (Vicia faba) flour and 20% of quinoa (Chenopodium quinoa) flour, was determined. Proximate chemical composition and iron, zinc and dietary fiber were determined. A biological assay was performed to assess the protein value using net protein utilization (NPU), true digestibility (TD) and protein digestibility-corrected amino acid score (PDCAAS). Iron and zinc availability were estimated by measuring dialyzable mineral fraction (%Da) resulting from in vitro gastrointestinal digestion. Nutritionally improved, gluten-free spaghetti (NIS) showed significantly increased NPU and decreased TD compared with a non-enriched control sample. One NIS-portion supplied 10–20% of recommended fiber daily intake. Addition of quinoa flour had a positive effect on the FeDa% as did broad bean flour on ZnDa%. EDTA increased Fe- and ZnDa% in all NIS-products, but it also impaired sensorial quality.