Assessment of Nutritional Value and Maillard Reaction in Different Gluten-Free Pasta.

Evaluating the nutritional quality and thermal damage effects of gluten-free foods is essential to ensure that people with gluten intolerance or celiac disease can safely meet their needs. In this work, fifteen different commercial gluten-free pasta samples made from cereals, pseudocereals, and pulses, alone or in mixed combinations, were analyzed to assess their nutritional value, essential amino acids composition, and protein chemical score. The occurrence of the Maillard reaction was investigated, and the levels of heat treatment markers (furosine, maltulose, hydroxymethylfurfural, and glucosylisomaltol) were determined. Analysis of the furosine values showed that pasta made with the same raw materials can have different degrees of thermal damage. There was no evidence of the Maillard reaction progressing in the advanced phase in any of the samples tested. Finally, the correlation between maltulose and furosine levels demonstrated the usefulness of combining the two markers to assess the extent of thermal damage.

The Nutritional Value and Biological Activity of Concentrated Protein Fraction of Potato Juice.

Potato protein is recognized as one of the most valuable nonanimal proteins due to the high content of essential amino acids. So far, it has not been used in human nutrition on a large scale due to technological limitations regarding its acquisition. In this study, the protein fraction of potato juice was concentrated with the use of membrane separation. The obtained potato juice protein concentrate (PJPC) was characterized in terms of nutritional value and biological activity, and the amino acid composition, mineral content, and antioxidant properties were determined. Moreover, in vitro cytotoxic activity against cancer cells of the gastrointestinal tract was investigated. The results of the present study indicate that PJPC is an excellent source of lysine and threonine, while leucine is its limiting amino acid, with an amino acid score (AAS) of 65%. Moreover, PJPC contains substantial amounts of Fe, Mn, K, and Cu. As demonstrated experimentally, PJPC is also characterized by higher antioxidant potential than potato itself. Biological activity, however, is not limited to antioxidant activity alone. Cytotoxicity studies using a gastric cancer cell line (Hs 746T), a colon cancer cell line (HT-29), and human colon normal cells (CCD 841 CoN) proved that PJPC is characterized by selective activity against cancer cells. It can thus be concluded that the developed method of producing protein concentrate from potato juice affords a product with moderate nutritional value and interesting biological activity.

Modificação da composição química de farinhas integrais de grãos de amaranto após a aplicação de diferentes tratamentos térmicos / Changes in chemical composition of whole flours from grains amaranth a fter different thermal treatments

O emprego do calor é uma alternativa utilizada com a finalidade de garantir a inocuidade, melhorar características sensoriais e aumentar a digestibilidade dos vegetais, tornando-os aptos ao consumo de crianças. No entanto, condições severas de calor podem alterar a sua composição nutricional. O objetivo deste trabalho foi avaliar o efeito do calor seco ou úmido, antes da moagem, na composição química de farinhas integrais de grãos de amaranto (Amaranthus cruentus). As farinhas foram produzidas de grãos integrais in natura (FIAI), tostados (FIAT), cozidos e secos (FIAC) e pipocados (FIAP). Os tratamentos térmicos aplicados aos grãos não afetaram os teores de minerais das farinhas, com exceção do Ca e Cu, mas elevaram os teores de lipídios (12 a 19%) e de fibra solúvel (18 a 35%) e reduziram de fibra insolúvel (5,8 a 8,5%) em comparação com à in natura. Os aminoácidos sulfurados foram os primeiros limitantes na FIAI, para idades de 1 a 10 anos e o pipocamento reduziu a qualidade aminoacídica do grão, que passou a ser limitante, também, em lisina para todas as idades. A tostagem e a cocção melhoraram o balanço aminoacídico das farinhas e os aminoácidos sulfurados deixaram de ser limitantes para maiores de três anos.

The use of heat is an alternative to ensure the safety, improve sensory characteristics and increase digestibility of vegetables, making them suitable for children consumption. However, severe heat conditions may alter its nutritional composition. The objective of this study was to evaluate the effect of dry or humid heat before milling in chemical composition of whole amaranth (Amaranthus cruentus) grain flours. The flours were produced from in nature whole grains (UGF), toasted (PGF), cooking and dried (CDF) and popping (PGF). The heat treatments applied to grains did not affect the mineral contents of the flour, with the exception of Cu and Ca. However, the treatment elevated the levels of lipids (12-19%) and soluble fiber (18-35%) and reduced the insoluble fiber (5.8-8.5%) of the flour when compared to in nature. The sulfur amino acids were first limiting in UGF, for 1-10 years old and the popping reduced the quality of the amino acids which has become limiting, too, in lysine, for all ages. The toasting and cooking improved the balance of amino acids of flours obtained and the sulfur amino acids ceased to be the limiting for children over three years.

Use of fungal proteases and selected sourdough lactic acid bacteria for making wheat bread with an intermediate content of gluten.

This study was aimed at combining the highest degradation of gluten during wheat flour fermentation with good structural and sensory features of the related bread. As estimated by R5-ELISA, the degree of degradation of immune reactive gluten was ca. 28%. Two-dimensional electrophoresis and RP-FPLC analyses showed marked variations of the protein fractions compared to the untreated flour. The comparison was also extended to in vitro effect of the peptic/tryptic-digests towards K562 and T84 cells. The flour with the intermediate content of gluten (ICG) was used for bread making, and compared to whole gluten (WG) bread. The chemical, structural and sensory features of the ICG bread approached those of the bread made with WG flour. The protein digestibility of the ICG bread was higher than that from WG flour. Also the nutritional quality, as estimated by different indexes, was the highest for ICG bread.