Application of statistical modelling of mixtures in the development of gluten-free bread with maca, potato, sweet and sour manioc / Aplicación de planificación de mezclar en el desarrollo de un pan sin gluten con maca, patata, yuca dulce y agria

ABSTRACT This study describes the development of mixed flour added of maca for gluten-free bread (GFB) employing a Simplex Centroid Design. Four pseudo-components were evaluated in order to improve the GFB specific volume and texture profile analysis: maca (MC; 0.25 to 0.75), potato starch (PS; 0.25 to 0.75), sweet manioc flour (SEM; 0 to 0.25), and sour manioc flour (SOM; 0 to 0.25). The best GFB formulation - by desirability results - was evaluated regarding physio-chemical, microbiological aspects, and sensory acceptance. The responses specific volume and hardness were adjusted with a special cubic model (R2= 0.973 and 0.913), while cohesiveness, springiness and chewiness was adjusted with a linear model. The significant contribution of maca into GFB dough was evident in the models, and the desirability results indicated an appropriate mixed flour composed by MC (0.25), PS (0.5), and SEM (0.25). The GFB elaborated with this mixed flour generated a product well accepted (acceptability index higher than 73.9%) for attributes of aroma, colour, texture, flavour, and overall acceptance. The values of physio-chemical parameters obtained in the present article was in the range described for GFB in the literature. In addition, the processing method applied allowed for obtaining a GFB that was microbiologically stable.

RESUMEN Este estudio describe el desarrollo de la harina mezclada (MF) agregada de maca para la elaboración de pan sin gluten (GFB) empleando un Diseño Centroide Simplex. Se evaluaron cuatro pseudo-componentes para mejorar el volumen específico y el perfil de textura de GFB: maca (MC; 0,25 a 0,75), almidón de patata (PS; 0,25 a 0,75), harina de yuca dulce (SEM; 0 a 0,25), y harina de yuca agrio (SOM; 0 a 0,25). La mejor formulación de GFB - por la deseabilidad - se evaluó en relación con los aspectos fisicoquímicos, microbiológicos, y sensoriales. El volumen específico y la dureza se ajustaron a un modelo cúbico especial (R2= 0,975 y 0,913). La cohesión, elasticidad y masticabilidad se ajustaron a un modelo lineal. La contribución de la maca a la masa de GFB fue evidente en los modelos, y los resultados indican una MF apropiada compuesta por MC (0,25), PS (0.5) y SEM (0,25). El GFB elaborado con esta MF genera un producto aceptado (índice de aceptabilidad mayor que 73,9%) para aroma, color, textura, sabor y aceptación general. Los parámetros físico-químicos obtenidos estaban en el rango descrito para GFB en la literatura y GFB se mostró microbiológicamente estable.

Obtainment, quantification and use of lactulose as a functional food - a review

Abstract Whey (milk serum) is produced by the dairy industry during the manufacture of cheese. In addition to being a valuable source of functional and nutritional proteins, whey also presents almost all the lactose from the original whole milk. However, many industries still consider the whey as an effluent, which can cause serious environmental problems when not properly treated. Therefore, it is important to develop alternatives for the adequate use of whey. The lactose obtained from whey permeate can be converted into lactulose, a prebiotic which may be metabolized in the intestine by probiotic bacteria, such as Lactobacillus sp. and Bifidobacterium sp., through enzymatic isomerization or by using alkaline catalysts, with minimal secondary reactions and high yield. This manuscript provides information about various techniques used to produce lactulose, its purification and analysis, as well as its mechanisms of action and alternative applications in food products and medicines.

Microbiological, physical, chemical and sensory characteristics of milk fermented with Lactobacillus plantarum / Caracterização microbiológica, físico-química e sensorial de leite fermentado com Lactobacillus plantarum

This study developed a fermented milk with Lactobacillus plantarum and evaluated its microbiological, physical-chemical and sensory characteristics during 70 days of storage at 10ºC. The study analyzed the counts of total viable cells, total and thermotolerant coliforms, yeast and mold; acidity, pH, ash, fat and total solids; sensory evaluation and purchase intention of the final product by consumers. Nutrition information was compared with seven commercial brands of fermented dairy products. The final formula contained 10% sugar, 6% milk powder and 4% microbial inoculum. The final product was fat-free. Acidity, ash content and total solids were stable during storage, unlike pH. No total or thermotolerant coliforms, yeast or mold were detected. L. plantarum counts ranged from 10.1 Log10 CFU mL-1 at the beginning to 8.9 Log10 CFU mL-1 at the end of the storage period. The product had good acceptance and high purchase intent. The nutrition information of fermented milk was similar to those of commercial brands evaluated. L. plantarum demonstrated good viability in fermented milk, and although not considered a probiotic food in Brazil, it is promising for the production of foods with functional properties and/or health claims.

Desenvolveu-se uma formulação de leite fermentado com Lactobacillus plantarum e avaliou-se seu comportamento microbiológico, físico -químico e sensorial durante 70 dias de armazenamento em refrigeração. Foi analisada a contagem total de células viáveis de Lactobacillus plantarum, coliformes totais e termotolerantes, e bolores e leveduras; acidez titulável, pH, teor de cinzas, gordura e extrato seco total; análise sensorial e intenção de compra do produto final. A informação nutricional do produto foi elaborada e comparada a sete leites fermentados. A formulação final conteve 10% de açúcar, 6% de leite em pó e 4% de inóculo microbiano. O produto final foi isento de gordura. A acidez, os teores de cinzas e o extrato seco total foram estáveis durante a estocagem, diferentemente do pH. Não foi detectada a presença de coliformes totais e termotolerantes, bolores e leveduras. A contagem do L. plantarum variou de 10,1 a 8,9 Log10 UFC mL-1, no início e final da estocagem. Obteve-se boa aceitação e intenção de compra do produto final. A informação nutricional do leite fermentado foi semelhante às marcas comerciais avaliadas. L. plantarum apresentou boa viabilidade em leite fermentado, e, embora não seja considerado um alimento probiótico no Brasil, o mesmo é promissor na produção de alimentos com propriedades funcionais e/ou de saúde.