Enhancement of antioxidant properties of Triticum durum obtained by traditional spontaneous fermentation in underground silos

Fermented foods have made important contributions to human diets for thousands of years and continue to do so. Their health-promoting benefits are attracting increasingly attention. The present study was conducted to evaluate the impact of natural fermentation on antioxidant properties of traditionally fermented wheat (Triticum durum) compared to unfermented samples. Initially, the samples were submitted to traditional spontaneous fermentation. Subsequently, an aqueous extract was obtained and used to determine polyphenolic and flavonoid contents. Moreover, the antioxidant potential was also measured through the determination of the scavenging ability against 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals, reducing power and hydrogen peroxide scavenging activity. The results showed that the total phenolic and total flavonoid contents were significantly increased in fermented wheat. Moreover, the antioxidant activity was more effective in fermented than in unfermented wheat. Thus, natural fermentation can enhance natural antioxidants in wheat and transform it into a healthy food or ingredient with multi-functional properties which can be used in the food industry.

Avaliação sensorial de pães de fermentação natural a partir de culturas starters inovadoras / Sensory evaluation of natural fermentation breads with innovative starter cultures

A fermentação sourdough para a produção de pães é fortemente motivada por seus efeitos benéficos quanto ao sabor, textura, vida de prateleira e pelas propriedades nutricionais dos produtos obtidos. Nesta pesquisa, estudou-se a aplicação dos micro-organismos Kluyveromyces marxianus, Dekkera bruxellensis e Lactobacillus plantarum como culturas starters alternativas na produção de pães. A partir de sete ensaios resultantes de um delineamento de mistura simplex-centroide, foram realizadas nos pães análises sensorial e instrumental. Observou-se que pães produzidos com L. plantarum apresentaram menor volume específico, enquanto que a mistura entre K. marxianus e L. plantarum exerceu influência positiva, possibilitando obter produtos de maior volume específico. A análise sensorial demonstrou a boa aceitabilidade para os pães produzidos com a mistura entre D. bruxellensis e K. marxianus e para a mistura entre os três micro-organismos. Os resultados deste trabalho demonstram a possibilidade do uso de culturas starters definidas para a fermentação sourdough, que é tradicionalmente obtida sem controle de processo.

The sourdough fermentation in bread making is strongly motivated due to its beneficial aspects on flavor, texture, shelf life, and the nutritional properties of the obtained products. In this research, the yeasts Kluyveromyces marxianus and Dekkera bruxellensis, and the bacterium Lactobacillus plantarum were used as alternative starter cultures in bread making. Experimental designs generated from simplex-centroid mixture were used in the sensorial analyses of breads. Results have shown that bread obtained with pure cultures of L. plantarum presented the smallest specific volume, while the mixture of K. marxianus and L. plantarum positively influenced the formation of good specific volume of products. Sensorial analysis showed good acceptability for breads obtained with D. bruxellensis and K. marxianus mixture, as well as for the mixture of the three microorganisms. The results obtained in this research suggest the possibility of using defined starter cultures for sourdough fermentation, which is traditionally carried out without any process controls.