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1.
Nutrition ; 121: 112264, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38458145

RESUMEN

OBJECTIVES: The lipid fraction, fatty acid profile, and diameter of fat globules of infant formulas show great differences from human milk. These characteristics influence fat digestion and, consequently, the development and health of infants. The aim of this study was to evaluate the diameter of fat globules in infant formulas and compare them with those in human milk. METHODS: The diameter of fat globules of 10 infant formulas and human milk samples was determined using scanning electron microscopy. RESULTS: The starter infant formula was the only one that showed a mean diameter value (3.52 ± 2.17 µm) similar to that obtained for human milk (3.44 ± 1.68 µm). The starter infant formula showed the highest values of volume-surface D3,2 (6.13 µm) and volume-weighted D4,3, (7.05 µm) mean diameters among the infant formulas analyzed, and close to those obtained for the human milk sample (5.16 and 5.98 µm, respectively). The infant formulas whey protein partially hydrolyzed, soy protein isolate-based, whey protein extensively hydrolyzed, and thickened with pregelatinized starch had the lowest mean diameters of fat globules 0.64 ± 0.22, 0.70 ± 0.19, 1.06 ± 0.34, and 1.22 ± 0.48 µm, respectively. CONCLUSION: The analysis of principal components showed that none of the analyzed infant formulas had similarity with the diameter of fat globules and the fatty acid profile of human milk.


Asunto(s)
Fórmulas Infantiles , Leche Humana , Lactante , Humanos , Proteína de Suero de Leche , Leche Humana/química , Ácidos Grasos/metabolismo , Glicoproteínas
2.
Braz J Microbiol ; 54(4): 3051-3060, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37910305

RESUMEN

Ozone has been studied to control microorganisms in food, as well as to control biofilm. In this context, the goals of this work were to determine the effect of ozonated water in the removal of Pseudomonas paracarnis biofilm and the effect of ozone gas and ozonated water on inactivating P. paracarnis in deboned chicken breast meat and its effect on product color. AISI 304 coupons were used as a surface for biofilm formation. The coupons were immerged into minimal medium for Pseudomonas inoculated with the P. paracarnis overnight culture (1% w/v) followed by incubation at 25 °C for 7 days. To obtain ozonized water, two different systems were used: system with microbubble generator (MB) and system with porous stone diffuser (PSD). The inlet ozone concentration was 19 mg/L and flow rate of 1 L/min. The coupons were subjected to ozonized water for 10 and 20 min. The chicken breast meat was exposed to gaseous ozone and ozonized water for 40 min. After the ozonation process, chicken meat samples were stored at 8 °C, for 5 days. More expressive removals of biofilm were obtained when using ozonized water obtained in the system with microbubble generator (MB for 20 min-reduction of 2.3 log cycles) and system with porous stone diffuser (PSD for 10 min-reduction of 2.7 log cycles; PSD for 20 min-reduction of 2.6 log cycles). The treatment of chicken meat with ozone gas resulted in lower counting of Pseudomonas, when compared with the control treatments and with ozonized water, both immediately after ozonation (day 1) and after 5 days of storage. The luminosity in the chicken meat samples treated with ozonized water was higher than that verified in the control treatments and with ozone gas, immediately after ozonation (day 1). A similar trend was observed in hue angle and color difference, in which the highest values were obtained for treatment with ozonized water. Based on the results obtained in this study, it was concluded that ozonated water can be used to remove P. paracarnis biofilm from stainless steel under static conditions and gaseous ozone is more efficient in the inactivation of P. paracarnis from chicken breast meat, when compared to ozonated water.


Asunto(s)
Ozono , Pseudomonas , Animales , Pollos , Ozono/farmacología , Biopelículas , Agua
3.
J Sci Food Agric ; 103(13): 6373-6382, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37205787

RESUMEN

BACKGROUND: The application of allyl isothiocyanate (AITC) has been proposed as an alternative to control stored-grain insects. However, AITC is a compound with a low diffusion coefficient, making its distribution throughout the grain mass difficult. Therefore, the objective of the present study was to evaluate the effectiveness of AITC applied in systems with or without recirculation for controlling Sitophilus zeamais (Mots. 1855) (Coleoptera: Curculionidae), Rhyzopertha dominica (Fabr.) (Coleoptera: Bostrichidae), and Tribolium castaneum (Herbst) (Coleoptera: Tenebrionidae) infesting a corn grain mass. The assays used a polyvinyl chloride (PVC) prototype, dimensioned 1.60 m in length, 0.30 m in diameter, and a static capacity of 60 kg of grains. AITC toxicity to insects was evaluated at the base, 0.5 m from the base, and top of the grain column (1.0 m). Different concentrations of AITC were tested for an exposure period of 48 h. RESULTS: In the system without AITC recirculation, insect mortality was verified only at the base of the grain column. However, insect mortality was considered uniform at the different positions of the column when the AITC recirculation system was adopted. In this system, there was also a marked reduction in the instantaneous population growth rate of S. zeamais, T. castaneum, and R. dominica, and a decrease in the dry matter loss of the grains, when the AITC concentrations were increased. CONCLUSION: AITC recirculation proved to be a viable strategy for protecting grains against the species S. zeamais, R. dominica, and T. castaneum. AITC fumigation ultimately did not cause changes in grain quality. © 2023 Society of Chemical Industry.


Asunto(s)
Escarabajos , Insecticidas , Tribolium , Gorgojos , Animales , Zea mays , Control de Insectos , Insectos , Grano Comestible
4.
J Sci Food Agric ; 103(3): 1183-1193, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36085570

RESUMEN

BACKGROUND: The ozonation of grains in a closed system at low pressure is a strategy with the potential for treating packaged products. Research is necessary to characterize the reaction kinetics of ozone in this type of injection system so that it is possible to design chambers and determine the ozone concentrations suitable for commercial-scale applications. The objective of this study was therefore to characterize the low-pressure ozone injection system in relation to the physical properties of the grains and determine possible changes in their quality. Samples (5 kg each) of common beans, cowpea beans, corn, popcorn kernels, paddy rice, and polished rice were exposed to ozone in a 70 L hypobaric chamber. Initially, the internal pressure of the chamber was reduced to 500 hPa. Then, ozone was injected at a concentration of 32.10 g m-3 at a volumetric flow rate of 1 L min-1 until reaching a pressure of 1000 hPa. To relate the decomposition of ozone to the grains that were being evaluated, different physical properties were determined, and quality analysis was conducted. RESULTS: Ozone gas half-life outside and inside the package depended on the grain type. Ozone decomposition was quickest in polished rice and slowest in common beans. The half-life of the different grains ranged from 17.8 to 52.9 and 16.4 to 52.9 min, outside and inside the package, respectively. Considering the physical properties, specific surface (Ss), surface area (SA), and sphericity (φ) exhibited a significant correlation with the decomposition rate constant (k) of ozone. However, the variables volume (V), permeability (K), porosity (ε), and specific mass (ρ) showed no correlation with k. CONCLUSION: The physical properties of grain influenced the reaction kinetics of ozone gas during the low-pressure injection process. Ozone gas injection at low pressures did not alter the quality attributes of the grains under study. © 2022 Society of Chemical Industry.


Asunto(s)
Fabaceae , Oryza , Ozono , Vigna , Ozono/química , Cinética , Semivida
5.
Anim Reprod Sci ; 240: 106974, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35439682

RESUMEN

Livestock production is considered an important factor influencing global warming; however, climate change has also been considered one of the major factors affecting livestock production and reproduction. The present study was carried out in the Southern region of Brazil and aimed to assess the seasonal influence of climatic factors and external morphology of the animals on the semen quality. Three ejaculates were obtained from each bull (Crioulo Lageano and Angus) in summer and winter seasons. Motile cells, sperm vigor, sperm concentration, sperm membrane status, and sperm abnormalities were analyzed in fresh and post-thawed semen. In addition, the sperm kinetics using CASA was assessed on post-thawed semen. Environmental data such as air temperature (AT), relative humidity (RH), mean radiant temperature (MRT) and temperature-humidity index (THI) were measured. Furthermore, body and testicular metrics, as well as hair coat characteristics, were recorded in each season on all bulls. Environmental traits differed significantly between seasons. Results of the PLS regression and Spearman's correlations confirmed a negative relationship between climatic variables and sperm traits in both seasons. Semen quality between breeds and seasons was similar, satisfactory, and heat stress was not sufficient to impair spermatozoa viability. External morphological traits were considered non-important in the final model. The findings of this study suggest that AT, MRT, and THI were the most important factors that could affect seminal characteristics of bulls raised in a subtropical climate.


Asunto(s)
Análisis de Semen , Preservación de Semen , Animales , Bovinos , Masculino , Fitomejoramiento , Estaciones del Año , Semen , Análisis de Semen/veterinaria , Preservación de Semen/veterinaria , Recuento de Espermatozoides/veterinaria , Motilidad Espermática , Espermatozoides
6.
Artículo en Inglés | MEDLINE | ID: mdl-35010860

RESUMEN

Meat is a source of protein widely consumed by the population in many countries due mainly to the nutritional aspects, sensory characteristics, and cultural aspects. The meat cooking preparation can promote significant changes in the meat's chemical composition and physical characteristics. Such transformations can impact both the acceptance of the product and consumers' health. Due to the different thermal processes altering the physical-chemical characteristics of meat, the present study aimed to evaluate the physicochemical characteristics of fillet steak submitted to different cooking methods: pan-frying with and without oil and air fryer. We performed the analysis to evaluate the physicochemical characteristics considering moisture, lipid, protein, ash, sodium, and potassium content, cooking loss index and colorimetry in three degrees of doneness of the meat, rare, medium, and well done. The fillet steak prepared by pan-frying with oil lost higher moisture and weight than the other samples. The air fryer method presented the highest moisture content. There was a significant difference in lipid content in which the pan-frying with oil fillet steak showed the highest amount of lipids. The pan-frying with oil steak fillet also presented more changes in the colorimetric parameters evaluated compared to the other samples. The pan-frying with oil cooking method promoted more pronounced changes in the steak fillet, and the cooking air fryer, the changes in meat quality are less pronounced. Therefore, the air fryer can be considered a good alternative for cooking meat.


Asunto(s)
Culinaria , Carne , Carne/análisis
7.
Foods ; 10(8)2021 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-34441559

RESUMEN

Vegetable consumption is associated with increased health benefits, and vegetables are consumed both in cooked form and raw form in salads. All cooking techniques cause changes in a vegetable's the nutrient content. Consumers are increasingly health-conscious and have less time to prepare meals, and they do not know which cooking times and cooking methods are best suited to preserve the nutrients. This study aimed to determine the best method of cooking vegetables to maintain minerals (potassium and sodium) and carotenoids. The studied vegetables were broccoli (Brassica oleracea, var. Italica), carrots (Daucus carota), and zucchini (Cucurbita moschata). The cooking methods were: boiling, steaming, combined oven, microwave steaming, and microwave cooking. Samples of organic and conventionally grown vegetables were prepared in triplicate. Samples were analyzed to determine the availability of target minerals and carotenoids in the raw food and in each recommended cooking situation according to technical standards. Only the carrot showed a higher concentration in organic cultivation for carotenoids in raw vegetables, with both zucchini and broccoli having higher concentrations when grown by conventional cultivation. The zucchini from organic cultivation presented a reduction of potassium and sodium, almost consistently, in all cooking techniques. Regarding the conventionally cultivated zucchini, potassium remained stable in boiling. Broccoli from organic and conventional cultivation showed similar potassium levels for boiling and traditional steam cooking. Organic carrots showed easier sodium extraction compared with conventional cultivation. Heat treatment, in general, improves the accessibility of carotenoids.

8.
Probiotics Antimicrob Proteins ; 13(1): 173-186, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-32601953

RESUMEN

The objective of this study was to isolate and characterize lactic acid bacteria with probiotic potential in silages of different species of forage plants, cocoa beans, and artisanal salami. The obtained isolates were submitted to the following evaluations: (i) screening for tolerance to pH 2 and bile salts, (ii) genotypic identification of isolates, (iii) survival in simulated gastric and pancreatic conditions, (iv) antimicrobial activity, (v) antibiotic susceptibility and safety, and (vi) properties associated with adhesion capacity. A total of 82 isolates were obtained and were screened for pH 2.0 tolerance and capacity to growth in the presence of bile salts (1.0 and 2.0%). Only 19 strains simultaneously presented tolerance to pH 2.0 and bile salts. These 19 strains were evaluated for genetic profile by Box-PCR. Subsequently, the selected strains were subjected to partial sequencing of the 16S rRNA gene. The species Lactobacillus plantarum was prevalent. The identified strains were evaluated for survival under simulated gastric and pancreatic conditions. Some strains have shown tolerance in both conditions. Different strains showed variations in antimicrobial activity, susceptibility to antibiotics, and properties associated with adhesion (hydrophobicity, autoaggregation, coaggregation, and adhesion to CaCo2 cells). All strains were negative for hemolysis, DNase, gelatinase, and biogenic amine synthesis activity. The L. plantarum SBR64.7 strain can be considered the most promising for it presented the lowest viability reduction when exposed to gastric and pancreatic juices.


Asunto(s)
Antibacterianos/aislamiento & purificación , Lactobacillus plantarum , Productos de la Carne/microbiología , Probióticos/aislamiento & purificación , Ensilaje/microbiología , Ácidos y Sales Biliares/metabolismo , Células CACO-2 , Humanos , Lactobacillus plantarum/clasificación , Lactobacillus plantarum/aislamiento & purificación
9.
Food Chem X ; 6: 100084, 2020 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-32373788

RESUMEN

Passiflora setacea is a wild species of passion fruit with interesting functional properties. Fruit seasonality demands conservation methods to enable its consumption throughout the year. We evaluated High Temperature Short Time (HTST) and Low Temperature Long Time (LTLT) binomials on physical, chemical, antioxidant and sensory characteristics of Passiflora setacea pulps. In natura (IN) and pasteurized pulps were analysed for DPPH, FRAP, ORAC, total phenolic content (TPC), vitamin C, bioactive amines, flavonoids, color, remaining enzymatic activity (REA), microbiological analyzes, sensory evaluation and physical stability. All binomials reached microbiological standards. Binomials 82 °C/20 s and 82 °C/40 s were selected for providing higher total antioxidant activity (TAA), TPC and lower REA. The highest levels of antioxidant activity, flavonoids, vitamin C were kept by 82 °C/20 s, without difference from IN pulp. LTLT binomial showed higher retention of bioactive amines, but also higher REA. Sensory acceptance was not affected by the binomials but pasteurized-cooked flavor was more checked for 82 °C 40 s than IN pulp.

10.
Probiotics Antimicrob Proteins ; 12(1): 320-324, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-30850942

RESUMEN

This study evaluated the in vitro effect of 3.0, 6.0, and 9.0% of green banana pulp (GBP) incorporation in fermented milk on the survival of Lactobacillus paracasei subsp. paracasei LBC 81 subjected to acid stress conditions and in the presence of bile salts. Tolerance to acid stress in pH 2.0 and in the presence of 0.30% of bile salts was evaluated right after the incorporation of the fermented milk in each of these conditions, and also during 3 and 4 h of exposure, respectively. The addition of GBP (3.0%) gives a protective effect on L. paracasei LBC 81 when exposed to stress conditions evaluated, while of 9.0% there is a marked decrease of L. paracasei LBC 81. In the absence of GBP, a decrease of L. paracasei LBC 81 is observed, but lower in the presence of GBP (9.0%).


Asunto(s)
Ácidos y Sales Biliares , Medios de Cultivo/metabolismo , Productos Lácteos Cultivados , Fermentación , Lactobacillus , Probióticos , Ácidos y Sales Biliares/metabolismo , Productos Lácteos Cultivados/análisis , Concentración de Iones de Hidrógeno , Lactobacillus/crecimiento & desarrollo , Lactobacillus/metabolismo , Musa
11.
Braz J Microbiol ; 50(1): 247-253, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30637637

RESUMEN

Ozone has a broad antimicrobial spectrum and each microorganism species has inherent sensitivity to the gas. The objective of this study was to evaluate the effect of ozone gas on Escherichia coli O157:H7 inoculated on an organic substrate, and the efficacy of ozonated water in controlling the pathogen. For the first experiment, E. coli O157:H7 (ATCC® 43890™) was inoculated in milk with different compositions and in water, which was ozonated at concentrations of 35 and 45 mg L-1 for 0, 5, 15, and 25 min. In the second experiment, water was ozonated at 45 mg L-1 for 15 min. E. coli O157:H7 was exposed for 5 min to the ozonated water immediately after ozonation, and after storage for 0.5, 1.0, 1.5, 3.0, and 24 h at 8 °C. The results showed that the composition of the organic substrate interfered with the action of ozone on E. coli O157:H7. In lactose-free homogenized skim milk, reductions of 1.5 log cycles were obtained for ozonation periods of 25 min at the concentrations tested. Ozonated water was effective in inactivating of E. coli O157:H7 in all treatments. The efficiency of ozone on E. coli O157:H7 is influenced by the composition of the organic substrates, reinforcing the need for adequate removal of organic matter before sanitization. Furthermore, refrigerated ozonated water stored for up to 24 h is effective in the control of E. coli O157:H7.


Asunto(s)
Escherichia coli O157/efectos de los fármacos , Viabilidad Microbiana/efectos de los fármacos , Ozono/farmacología , Animales , Bovinos , Recuento de Colonia Microbiana , Escherichia coli O157/crecimiento & desarrollo , Microbiología de Alimentos , Leche/microbiología
12.
J Food Sci Technol ; 55(12): 4851-4858, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30482980

RESUMEN

The objective of this study was to evaluate the characteristics of kefir beverages made from yam, sesame and bean extracts after fermentation of the extracts with water kefir grains. Formulations were prepared with raw and boiled yams. To the yam extract, sesame and different percentages of white bean extract were added. The fermentation kinetics, the chemical composition and color of the extracts were analyzed. To determine the fermentation kinetic parameters, pH and titratable acidity were evaluated. The chemical composition and color of all extracts were determined before and after fermentation process. The decrease in pH and increase in titratable acidity were affected both by raw or boiler yam. The addition of bean extract favored the decrease in pH of formulations containing extracts of raw or boiled yams. Chemical composition and color of the beverages were altered after fermentation. The kefir beverage made from yam and sesame enriched with 50% beans proved to be an excellent fermentation substrate. In addition, it is a new way of consuming vegetable products, especially fermented products, which have limited diversity to serve vegan consumers and also people with certain allergies to dairy products.

13.
Nutrients ; 10(4)2018 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-29596319

RESUMEN

The aims of this study were (i) to evaluate the growth kinetic of L. paracasei LBC 81 in fermented milks enriched with green banana pulp (GBP); (ii) to evaluate the effect of the incorporation of GBP on the chemical composition and the sensory acceptance; and (iii) to study the viability of the probiotic and technological properties during refrigerated storage. The amount of GBP used were 3.0, 6.0 and 9.0 g/100 g. The results show that the higher the concentration of GBP added, the shorter the time taken to reach pH 4.6. It was observed that the incorporation of GBP did not affect negatively the viability of L. paracasei LBC 81 during storage. The fermented milk elaborated with 6.0 g/100 g of GBP was the most accepted. The present study indicates that the enrichment of fermented milk with GBP favors the stability of the probiotic strain, L. paracasei LBC 81 during storage.


Asunto(s)
Productos Lácteos Cultivados , Frutas , Lacticaseibacillus paracasei/fisiología , Musa , Probióticos , Adolescente , Adulto , Bebidas , Comportamiento del Consumidor , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven
14.
J Sci Food Agric ; 92(4): 899-905, 2012 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-22095762

RESUMEN

BACKGROUND: Peanut contamination by fungi is a concern of processors and consumers owing to the association of these micro-organisms with quality deterioration and aflatoxin production. In this study the fungicidal and detoxifying effects of ozone on aflatoxins in peanuts was investigated. Peanut kernels were ozonated at concentrations of 13 and 21 mg L⁻¹ for periods of 0, 24, 48, 72 and 96 h. RESULTS: Ozone was effective in controlling total fungi and potentially aflatoxigenic species in peanuts, with a reduction in colony-forming units per gram greater than 3 log cycles at the concentration of 21 mg L⁻¹ after 96 h of exposure. A reduction in the percentage of peanuts with internal fungal populations was also observed, particularly after exposure to ozone at 21 mg L⁻¹. A reduction in the concentrations of total aflatoxins and aflatoxin B1 of approximately 30 and 25% respectively was observed for kernels exposed to ozone at 21 mg L⁻¹ for 96 h. CONCLUSION: It was concluded that ozone is an important alternative for peanut detoxification because it is effective in controlling potentially aflatoxigenic fungi and also acts in the reduction of aflatoxin levels in kernels.


Asunto(s)
Aflatoxinas/análisis , Arachis/microbiología , Aspergillus/efectos de los fármacos , Contaminación de Alimentos/prevención & control , Conservación de Alimentos/métodos , Fungicidas Industriales/farmacología , Ozono/farmacología , Aflatoxina B1/análisis , Arachis/química , Aspergillus/crecimiento & desarrollo , Aspergillus/aislamiento & purificación , Aspergillus/metabolismo , Aspergillus flavus/efectos de los fármacos , Aspergillus flavus/crecimiento & desarrollo , Aspergillus flavus/aislamiento & purificación , Aspergillus flavus/metabolismo , Brasil , Recuento de Colonia Microbiana , Enfermedades Transmitidas por los Alimentos/prevención & control , Hongos/efectos de los fármacos , Hongos/crecimiento & desarrollo , Hongos/aislamiento & purificación , Hongos/metabolismo , Viabilidad Microbiana/efectos de los fármacos , Semillas/química , Semillas/microbiología , Factores de Tiempo
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