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1.
Carbohydr Polym ; 175: 603-609, 2017 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-28917907

RESUMO

The objective of this work was to microencapsulate pitanga (Eugenia uniflora L.) juice by spray drying, using High Performance Agave Fructans (HPAF) and High Degree of Polymerisation Agave Fructans (HDPAF) and maltodextrin (MD), respectively, as the wall materials. The physicochemical and antioxidant properties of the capsules during storage at various temperatures were evaluated. The microparticles developed using fructans HPAF and HDPAF, exhibited similar physicochemical and flow properties to those presented by the microparticles prepared with MD. The highest yield and concentration of anthocyanins after drying and during storage were found for a 1:6 core:wall material ratio. The total color change was a good indicator of the microcapsule stability. This study showed that both fructans fraction possess similar encapsulating properties to MD and that the HDPAF were more efficacious than MD at protecting the antioxidants during drying and storage.


Assuntos
Antocianinas/análise , Eugenia , Frutanos/química , Sucos de Frutas e Vegetais , Antioxidantes/química , Dessecação , Composição de Medicamentos
2.
Ultrason Sonochem ; 24: 204-13, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25572417

RESUMO

Bioactive compounds such as ω-3 fatty acids and terpenes, have been associated with beneficial health effects; however, their solubility in the gastrointestinal tract and its bioavailability in the body are low. Nanoemulsions offer a viable alternative to disperse lipophilic compounds and improve their dissolution, permeation, absorption and bioavailability. Enzyme modified phosphatidylcholine (PC) with ω-3 fatty acids was used as emulsifier to stabilize oil-in-water nanoemulsions generated using ultrasound device. These systems were used as carriers of betulinic acid, which has reported anti-carcinogenic activity. Phospholipase-catalyzed modification of PC allowed the incorporation of 50 mol% of ω-3 fatty acids. Formation variables such as oil type and ultrasound amplitude had effects on nanoemulsion characteristics. Incorporation of betulinic acid affected globule size; however, betulinic acid nanoemulsions below 200 nm could be prepared. The conditions under which betulinic acid nanoemulsions were obtained using the modified phosphatidylcholine with the smaller globule size (91 nm) were 10% PC, 25% glycerol, medium chain oil and 30% amplitude for 12 min in the sonicator. Storage temperature had an effect on the stability of the nanoemulsions, at 5°C we observed the smallest growth in globule size. The use of olive oil decreased the globule size growth during storage of the nanoemulsion stabilized with modified phosphatidylcholine, although globule size obtained was greater than 200 nm. Medium pH had a significant effect on the nanoemulsions; alkaline pH values improved storage stability. These results provide useful information for using this type of carrier system on the formulation of products in the pharmaceutical or food industry.


Assuntos
Ácidos Graxos Ômega-3/química , Nanoestruturas/química , Fosfatidilcolinas/química , Triterpenos/química , Emulsões , Concentração de Íons de Hidrogênio , Triterpenos Pentacíclicos , Sonicação , Substâncias Reativas com Ácido Tiobarbitúrico/química , Ondas Ultrassônicas
3.
Plant Foods Hum Nutr ; 67(1): 57-63, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22318745

RESUMO

Porophyllum tagetoides is an annual warm-weather herb that has an intense typical smell. Its leaves are commonly used in soup preparation and traditional medicine for treatment of inflammatory diseases. Its volatile compounds and antioxidant properties were evaluated in crude, aqueous and ethanol leaf extract and an oil emulsion using different antioxidant assays in vitro, such as: DPPH radical scavenging activity, redox potential, polyphenol content, reducing power and optical density. A high antioxidative activity was found when comparing leaves with stems. The crude extract from leaves showed a very high reducing power (2.88 ± 0.20 O.D.) and DPPH radical-scavenging activity (54.63 ± 4.80%), in concordance with a major concentration of vitamin C (23.97 ± 0.36 mg/100 g). Instead, the highest polyphenol content (264.54 ± 2.17 mg GAE/g of sample) and redox potential (561.23 ± 0.15 mV) were found by the ethanol and aqueous extract, respectively. Aldehydes and terpenes such as nonanal, decanal, trans-pineno, ß-myrcene and D-limonene were the major volatiles found. This study suggests that Porophyllum tagetoides extracts could be used as antioxidants.


Assuntos
Antioxidantes/análise , Asteraceae/química , Sequestradores de Radicais Livres/análise , Óleos Voláteis/análise , Extratos Vegetais/química , Polifenóis/análise , México , Oxirredução , Folhas de Planta/química , Caules de Planta/química
4.
Cryo Letters ; 25(6): 405-14, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15660167

RESUMO

Several modifications to the cryogenic protocols previously described for pineapple apices were performed using vitrification and encapsulation-vitrification. Pregrowth of apices in sucrose-proline before loading significantly reduced the exposure duration to PVS2 and PVS3 required for successful cryopreservation. Encapsulation and treatments with PVS3 at 0 degree C gave the highest survival before and after cooling. Optimal conditions involved the encapsulation of pineapple apices in calcium alginate (3 percent) followed by a 2-d preculture in liquid medium with 0.16 M sucrose + 0.3 M proline for 24 h and then transfer to 0.3 M sucrose + 0.3 M proline for an additional 24 h. After preculture, samples were loaded in 0.75 M sucrose + 1 M glycerol solution at room temperature (25 min) and dehydrated with PVS3 at 0 degree C for 60 min before immersion into liquid nitrogen. Following this procedure 54 percent and 83 percent of apices from MD-2 and Puerto Rico varieties respectively survived.


Assuntos
Ananas , Criopreservação/métodos , Brotos de Planta , Desidratação
5.
Arch Latinoam Nutr ; 48(3): 247-9, 1998 Sep.
Artigo em Espanhol | MEDLINE | ID: mdl-9951539

RESUMO

A sucrose syrup of 70 degrees Brix was concentrated until a concentration greater than 95 degrees Brix was attained. It was studied the effect of concentration (20, 25 and 35 degrees Brix) on the physical properties of the cucumber (Cucumis sativa L.) granules. Moisture content, solubility, and density were determined. The best results were found for the concentrated at 30 degrees Brix. Lemon juice was added to the concentrated to decrease pH from 5.5 to 4.0 to improve flavor and to avoid growth of molds and yeast. No significant differences in the higroscopicity were found between both pH (s). Sensory evaluation shows that 30 judges of 45 preferred the sample made with the co-crystallizate containing lemon juice.


Assuntos
Cristalização , Cucumis sativus/química , Sacarose
6.
Arch Latinoam Nutr ; 41(2): 238-45, 1991 Jun.
Artigo em Espanhol | MEDLINE | ID: mdl-1811453

RESUMO

The foam-mat production and stability using pineapple juice concentrate (25, 30 and 40 degrees Brix), adding a surfactants mixture and maltodextrin (DE 10) as co-adjuvant, stirred in a commercial mixer, was studied. Adequate foam formation conditions were as follows: concentrate of 25 degrees Brix using surface active agents (Sorbac 60-Polisorbac 80) 0.285% surface active agent/total solids, HLB = 6, and stirring time, 7 min. The foam was dehydrated in an oven dried with a horizontal air flow circulation set at 60, 70 and 80 degrees C using 3, 5 and 10 mm bed depths. The best conditions were obtained at 60 degrees C and 5 mm bed depth. The product had a particle size of sieve 40-80, and a moisture content of 3%. It was then packaged in multilayer plastic film and stored at environmental conditions. No brown color formation or mold growth was detected during storage. Pineapple juice and a refreshing drink were prepared. The general acceptability in a community indicated that 95% of the population involved accepted the product.


Assuntos
Bebidas , Tecnologia de Alimentos , Frutas
7.
Arch. latinoam. nutr ; 41(2): 238-45, jun. 1991. tab
Artigo em Espanhol | LILACS | ID: lil-103084

RESUMO

Se estudió la formación y estabilidad de las espumas a partir de jugo de piña concentrado a 25, 30 y 40- Brix, al cual se le adicionó una mexcla de agentes surfactantes y, como coadyuvante, de secado maltodextrina DE=10. Agitándose en una batidora comercial, se obtuvieron espumas adecuadas con el jugo a 25- Brix en las condiciones siguientes: concentración de agentes sufactantes (Sorbac 60-Polisorbac 80), 0.285% de surfactantes/sólidos totales; balance lipofílico-hidrofílico (HLB) 6 y tiepo de agitación 7 min. La espuma se deshidrató en un horno secador con flujo de aire horizontal a 60-C y un espesor de cama de 5mm. El producto con un tamaño de partícula 40-80 y contenido de humedad de 3% se almacenó por seis meses en un empaque flexible de cinco colaminados a las condiciones ambientales. No hubo oscurecimiento de hongos y bacterias durante el tiempo observado. El producto se evaluó sensorialmente preparando jugo de piña y una bebida refrescante, y tuvo una aceptacíon superior al 95% a nivel de comunidad


Assuntos
Bebidas , Frutas , Manipulação de Alimentos/métodos
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