Peptide separation of commercial fermented milk during refrigerated storage

Milk is an important source of bioactive compounds. Many of these compounds are released during fermentation and refrigerated storage. The aim of this study was to determine the release of peptides by lactic acid bacteria in commercial fermented milk during refrigerated storage. The size and profile of peptides were analyzed by polyacrylamide gel electrophoresis and sizeexclusion HPLC. During electrophoresis, it was observed that the peptides were released from caseins, whereas β-lactoglobulin was the whey protein with the highest degradation. HPLC analysis confirmed the pattern of peptide formation observed in electrophoresis. Two fractions lower than 2 kDa with aromatic amino acids in their structure were separated. These results were consistent with those reported for structures of peptides with antihypertensive activity. Therefore, the presence of aromatic amino acids in the peptide fractions obtained increases the likelihood of finding peptides with such activity in refrigerated commercial fermented milk. In conclusion, during cold storage, peptides with different molecular weights are released and accumulated. This could be due to the action of proteinases and peptidases of the proteolytic system in lactic acid bacteria

Comparative Evaluation of Four Extraction Methods of Antioxidant Compounds from Decatropis bicolor in Aqueous Medium Applying Response Surface Design

The objective of this paper is to compare conventional, ultrasound, microwave, and French press methods for the extraction of antioxidant compounds from Decatropis bicolor in an aqueous medium. This plant is widely used in Mexican traditional medicine for breast cancer treatment. Despite that, there are few studies on D. bicolor. Two response surface designs were applied to establish the best conditions of the liberation of antioxidants from D. bicolor, which were determined by DPPH• and Ferric Reducing Antioxidant Power (FRAP) techniques. The total phenolic content was evaluated by the Folin-Ciocalteu method. The results showed that D. bicolor is a source of antioxidants (669–2128 mg ET/100 g and 553–1920 mg EFe2+/100 g, respectively) and phenolic compounds (2232–9929 mg EGA/100 g). Among the physical factors that were analyzed, the temperature was the determinant factor to liberate the compounds of interest by using low concentrations of the sample and short times of extraction. The French press was the most efficient method, obtaining values of antioxidant activity and phenolic compounds even higher than those reported by using extraction methods with solvents such as methanol

Propiedades fisicoquímicas y sensoriales de harinas para preparar atole de amaranto Physicochemical and sensory properties of flours ready to prepare an amaranth "atole"

El atole es una bebida prehispánica mexicana tradicionalmente preparada con maíz; sin embargo cereales como el arroz y el amaranto también han sido usados empleados. El objetivo fue caracterizar las propiedades fisicoquímicas y sensoriales de una harina para preparar una bebida (atole) a base de amaranto a fin de determinar su aporte nutricional. El análisis bromatológico del atole de amaranto y de las marcas comerciales (a base de maíz y arroz) fue realizado siguiendo las técnicas de la AOAC. El análisis de minerales se llevó a cabo mediante espectrofotometría de absorción atómica. La determinación de la viscosidad se realizó en un reómetro en un intervalo de temperatura de 25 a 90ºC. El perfil descriptivo cuantitativo (QDA) del atole de amaranto fue determinado por un panel de 10 jueces entrenados. El atole de amaranto presentó un mayor contenido de proteína y grasa que los atoles de maíz y arroz. En general, sodio y potasio fueron los macrominerales más abundantes. Los atoles de maíz y arroz presentaron una viscosidad constante de 20 a 84ºC, a partir de 85ºC se observó un incremento importante de ésta; en el atole de amaranto se detectó este incremento a 75ºC. Los descriptores definidos por los jueces entrenados para los perfiles descriptivos cuantitativos de los atoles de amaranto fueron: almidón, almendra/cereza, caramelo macizo, vainilla, fresa, nuez y chocolate. El atole de amaranto, respecto a los atoles de maíz y arroz, presentó el mejor perfil nutricional, destacando su aporte proteico.Atole is a Mexican prehispanic drink prepared traditionally with corn; however, cereals as wheat, rice and amaranth have also been used. The aim of this study was to determine the physicochemical and sensory properties of an amaranth flour to prepare a drink (atole) mentioned above, in order to determine its nutritive value. Proximate analysis of the amaranth, corn and rice drink flours was determined by means of official techniques of AOAC. Mineral content was carried out by atomic absorption spectrometry. Viscosity was measured in a reometer from 25 to 90ºC. The quantitative descriptive profile (QDA) of the amaranth drink was studied by a trained panel of 10 judges. Results showed that the amaranth drink flour presented the highest protein and fat content compared to corn and rice drink flours. Sodium and potassium were the most abundant minerals in all flours studied. Corn and rice drink flours showed a constant viscosity from 20 to 84ºC, to 85ºC an important increase in this parameter was observed. This increase was detected in the amaranth drink flour to 75ºC. Descriptors defined by trained judges for the QDA of the amaranth drink flours were: starch, almond/cherry, caramel, vanilla, strawberry, walnut and chocolate. The amaranth drink flour, compared to corn and rice drink flours, presented the best nutritional profile; it is important to emphasize its protein content

Antithrombotic Activity of Milk Protein Hydrolysates by Lactic Acid Bacteria Isolated from Commercial Fermented Milks

ABSTRACT In the last decade, thrombosis has been one of the pathologies with high incidence creating great concern in Health Institutes all around the world. Considering this, the aim of this research was to determine the antithrombotic activity of peptides released during lactic fermentation. Reconstituted skim milk powder was fermented by Lactobacillus casei Shirota and Lactobacillus johnsonii LA1 isolated from commercial fermented milks. The hydrolysis degree and proteolytic profile were analyzed by trinitrobenzenesulfonic acid spectrophotometry method and by peptide polyacrylamide electrophoresis gel separation. The milk fermented by Lactobacillus casei Shirota exhibited a higher concentration of free amino groups than that fermented by Lactobacillus johnsonii LA1. Additionally, in both fermentation systems peptides with molecular weights lower than 1.4 kDa were observed. The highest inhibition of thrombin (31.67±2.35%) was observed in milk fermented by Lactobacillus johnsonii LA1 at 10 hours of fermentation. Finally, no relationship was found between the antithrombotic capacity and the proteolytic profile

Propiedades fisicoquímicas y sensoriales de harinas para preparar atole de amaranto

El atole es una bebida prehispánica mexicana tradicionalmente preparada con maíz; sin embargo cereales como el arroz y el amaranto también han sido usados empleados. El objetivo fue caracterizar las propiedades fisicoquímicas y sensoriales de una harina para preparar una bebida (atole) a base de amaranto a fin de determinar su aporte nutricional. El análisis bromatológico del atole de amaranto y de las marcas comerciales (a base de maíz y arroz) fue realizado siguiendo las técnicas de la AOAC. El análisis de minerales se llevó a cabo mediante espectrofotometría de absorción atómica. La determinación de la viscosidad se realizó en un reómetro en un intervalo de temperatura de 25 a 90ºC. El perfil descriptivo cuantitativo (QDA) del atole de amaranto fue determinado por un panel de 10 jueces entrenados. El atole de amaranto presentó un mayor contenido de proteína y grasa que los atoles de maíz y arroz. En general, sodio y potasio fueron los macrominerales más abundantes. Los atoles de maíz y arroz presentaron una viscosidad constante de 20 a 84ºC, a partir de 85ºC se observó un incremento importante de ésta; en el atole de amaranto se detectó este incremento a 75ºC. Los descriptores definidos por los jueces entrenados para los perfiles descriptivos cuantitativos de los atoles de amaranto fueron: almidón, almendra/cereza, caramelo macizo, vainilla, fresa, nuez y chocolate. El atole de amaranto, respecto a los atoles de maíz y arroz, presentó el mejor perfil nutricional, destacando su aporte proteico

Propiedades fisicoquímicas y sensoriales de harinas para preparar atole de amaranto

El atole es una bebida prehispánica mexicana tradicionalmente preparada con maíz; sin embargo cereales como el arroz y el amaranto también han sido usados empleados. El objetivo fue caracterizar las propiedades fisicoquímicas y sensoriales de una harina para preparar una bebida (atole) a base de amaranto a fin de determinar su aporte nutricional. El análisis bromatológico del atole de amaranto y de las marcas comerciales (a base de maíz y arroz) fue realizado siguiendo las técnicas de la AOAC. El análisis de minerales se llevó a cabo mediante espectrofotometría de absorción atómica. La determinación de la viscosidad se realizó en un reómetro en un intervalo de temperatura de 25 a 90ºC. El perfil descriptivo cuantitativo (QDA) del atole de amaranto fue determinado por un panel de 10 jueces entrenados. El atole de amaranto presentó un mayor contenido de proteína y grasa que los atoles de maíz y arroz. En general, sodio y potasio fueron los macrominerales más abundantes. Los atoles de maíz y arroz presentaron una viscosidad constante de 20 a 84ºC, a partir de 85ºC se observó un incremento importante de ésta; en el atole de amaranto se detectó este incremento a 75ºC. Los descriptores definidos por los jueces entrenados para los perfiles descriptivos cuantitativos de los atoles de amaranto fueron: almidón, almendra/cereza, caramelo macizo, vainilla, fresa, nuez y chocolate. El atole de amaranto, respecto a los atoles de maíz y arroz, presentó el mejor perfil nutricional, destacando su aporte proteico.Atole is a Mexican prehispanic drink prepared traditionally with corn; however, cereals as wheat, rice and amaranth have also been used. The aim of this study was to determine the physicochemical and sensory properties of an amaranth flour to prepare a drink (atole) mentioned above, in order to determine its nutritive value. Proximate analysis of the amaranth, corn and rice drink flours was determined by means of official techniques of AOAC. Mineral content was carried out by atomic absorption spectrometry. Viscosity was measured in a reometer from 25 to 90ºC. The quantitative descriptive profile (QDA) of the amaranth drink was studied by a trained panel of 10 judges. Results showed that the amaranth drink flour presented the highest protein and fat content compared to corn and rice drink flours. Sodium and potassium were the most abundant minerals in all flours studied. Corn and rice drink flours showed a constant viscosity from 20 to 84ºC, to 85ºC an important increase in this parameter was observed. This increase was detected in the amaranth drink flour to 75ºC. Descriptors defined by trained judges for the QDA of the amaranth drink flours were: starch, almond/cherry, caramel, vanilla, strawberry, walnut and chocolate. The amaranth drink flour, compared to corn and rice drink flours, presented the best nutritional profile; it is important to emphasize its protein content

Kinetic parameters of lipid oxidation in third generation (3G) snacks and its influence on shelf-life

Abstract In food systems, lipid oxidation is one of the most important factors affecting food quality, nutrition, safety, color and consumer acceptance. The objective of this study was to determine the kinetic parameters of lipid oxidation and its influence in the shelf life of third generation (3G) snacks stored in three types of packaging (polyethylene, polypropylene + Kraft paper, and polyethylene + polypropylene) at 25 °C and 40 °C. The peroxide value was the quality parameter selected and monitored for a 60 day period using a spectrophotometric technique. Based on the Arrhenius equation and activated complex theory, reaction rate constants (k), activation energies (Ea), Q10 factors, activation enthalpies (∆H‡), and activation entropies (∆S‡ ) for oxidative stability in 3G snacks were calculated. Results showed that oxidation phenomena can occur in the 3G snacks and affect its shelf-life. Packaging C (polyethylene + polypropylene) was the most appropriate for the storage of this kind of product. Finally, the shelf life of the analyzed pellets was longer than one year at 25 °C and it may be extended with the appropriate mix of packaging materials

The Activity of Prebiotics and Probiotics in Hepatogastrointestinal Disorders and Diseases Associated with Metabolic Syndrome

The components of metabolic syndrome (MetS) and hepatogastrointestinal diseases are widespread worldwide, since many factors associated with lifestyle and diet influence their development and correlation. Due to these growing health problems, it is necessary to search for effective alternatives for prevention or adjuvants in treating them. The positive impact of regulated microbiota on health is known; however, states of dysbiosis are closely related to the development of the conditions mentioned above. Therefore, the role of prebiotics, probiotics, or symbiotic complexes has been extensively evaluated; the results are favorable, showing that they play a crucial role in the regulation of the immune system, the metabolism of carbohydrates and lipids, and the biotransformation of bile acids, as well as the modulation of their central receptors FXR and TGR-5, which also have essential immunomodulatory and metabolic activities. It has also been observed that they can benefit the host by displacing pathogenic species, improving the dysbiosis state in MetS. Current studies have reported that paraprobiotics (dead or inactive probiotics) or postbiotics (metabolites generated by active probiotics) also benefit hepatogastrointestinal health

Nutritional Characterization of the Functional and Antioxidant Activity of Cactus Flowers from Hidalgo, Mexico

Flowers have traditionally been used in the production of various dishes to improve the sensory aspects of food. In this study, the nutritional and functional composition of cactus flowers was evaluated for their possible use in the food industry. The objective of this research was also to identify the main secondary metabolites of flowers by HPLC/ESI/MS analyses. The findings indicated that the most abundant components of the flowers were carbohydrates, followed by ash and proteins. The highest antioxidant capacity, assessed by DPPH• and ABTS•+ assays, was observed in Echinocereus cinerascens, with values of 255.08 and 392.65 µM Trolox equivalents (TE)/g, respectively. These values were also correlated with a high content of phenolic compounds. Forty-four secondary metabolites were detected in total, of which the most predominant corresponded to compounds such as quercetin and isorhamnetin, as well as their derivatives, protocatechuic acid and apigenin. This study indicates that Cactaceae flowers could be a source of nutrients; in addition, the diversity of compounds and their good antioxidant properties suggest that they should be considered as new sources of natural antioxidant compounds in the elaboration of functional products

Organic Acids, Antioxidants, and Dietary Fiber of Mexican Blackberry (Rubus fruticosus) Residues cv. Tupy

Blackberry fruit processing generates residues comprised of peel, seeds, and pulp that are abundant in flavonoids, colorants, and organic acids. The objective of this study was to determine the organic acids, antioxidants, and dietary fiber content of blackberry residues and compare antioxidants and dietary fiber content of a prune-based commercial product. The ABTS, DPPH, and FRAP methodologies were used for antioxidant capacity. The blackberry residues exhibited a high amount of malic acid (5706.37 mg/100 g db), phenols (4016.43 mg GAE/100 g db), and anthocyanins content (364.53 mg/100 g db) compared with the commercial product. These compounds contributed to the antioxidant capacity (by ABTS) of both products but were 20 times higher in blackberry residues. The fruit residues were able to reduce iron (by FRAP) 4.4 times compared to the prune-based product. Total dietary fiber (44.26%) and functional properties as water retention capacity (2.94 g/g), swelling capacity (5.00 mL/g), and fat absorption capacity (1.98 mL/g) of blackberry residues were significantly higher than those of the commercial sample. The results demonstrated that, due to its antioxidant compounds and functional properties, the blackberry residue can be considered a source of components with potential benefit to human health