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1.
Int J Vitam Nutr Res ; 93(4): 298-307, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34542320

RESUMO

In ASEAN countries, small freshwater fish species contribute to the nutritional needs of people with few livelihoods by providing them with significant amounts of protein, fat, vitamins and minerals. Some species are eaten whole (with their organs, skin, bones, head and eyes). To estimate the vitamin A content of these foods, conventional saponification has been applied but has not been able to fully release the retinol. Our objective was to optimise the conditions of vitamin A saponification in whole fish to have a reliable estimate of their contribution to intakes. The effects of temperature and saponification time on the retinol quantification of whole fish were evaluated using a two-factor experimental design. Reaction time had a significant effect on the saponification of standard retinyl palmitate and whole fish (p≤0.05). For whole fish, the best conditions for the saponification were to heat the samples to 80 °C for 43 minutes. Under these conditions, the retinol is well liberated from the matrix and protected from degradation and isomerisation reactions. The time-temperature couple used is more intense than that recommended for quantifying vitamin A in milk or enriched margarines. The protective effect of the food matrix against the release of retinol is evident. Vitamin A2 alcohol (3,4-didehydroretinol) was detected in five species and the overall vitamin A contents ranged from 9.6 to 737.5 µg RE/100 g in species frequently consumed in Cambodia. The two species of small fish consumed whole were the ones that contained significantly more vitamin A among the ten tested (p≤0.05). Highlights: Vitamin A2 alcohol was quantified in five fish species. The official saponification partially released retinol in whole fish. The optimised reaction required heating the sample to 80 °C for 43 min.


Assuntos
Vitamina A , Vitaminas , Animais , Projetos de Pesquisa , Vitamina K
2.
Int J Vitam Nutr Res ; 91(5-6): 439-450, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34134516

RESUMO

Vegetables rich in vitamin K consumption could prevent bleeding and maintain bone status. The aims of the present work were to investigate i) the effect of household cooking (i.e., boiling for 5 min at 100 °C in distilled water and stir-frying for 3 min at 180 °C in hot canola oil) on phylloquinone bioaccessibility of five rich phylloquinone leafy vegetables, namely Water spinach (Ipomoea aquatic Forssk), Amaranth (Amaranthus blitum subsp. oleraceus L.), Chinese broccoli (Brassica alboglabra), Pak choi (Brassica rapa L.) and Drumstick (Moringa oleifera Lam.), and ii) the structural changes of these leaves before and after in vitro gastro-intestinal digestion. All the experiments were realized in triplicate for each vegetable. The amounts of phylloquinone in leafy vegetables were noticeable in almost all species and ranged from 94 to 182 µg/100 g DM. Their cell wall polysaccharide contents greatly varied from 4.3 to 8.4 g for 100 g. The content in bioaccessible phylloquinone was low in raw leaves (<25 µg/100 g DM) as well as its bioaccessibility (<15%). Leaf pectin content impaired phylloquinone bioaccessibility using principal component analysis. Boiling and stir-frying significantly improved the bioaccessibility of phylloquinone in leaves by a factor of three to twelve and two to seven respectively (p<0.05). These variations were associated with changes in leaf structure. Palisade and spongy cells appeared ruptured and disorganized after stir-frying. Given the estimated bioaccessibility of phylloquinones, the consumption of 500 g of cooked wet leaves per day would cover phylloquinone needs of an individual adult average body weight.


Assuntos
Verduras , Vitamina K 1 , Disponibilidade Biológica , Parede Celular , Culinária , Digestão
3.
Food Nutr Bull ; 35(4): 449-57, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25639130

RESUMO

BACKGROUND: Simple-to-use quantitative methods are needed to check the adequacy of vitamin A fortification levels. OBJECTIVE: To assess the capacity of a portable fluorometer (iCheck FLUORO) and its test kit vials (iEx Mila) to quantify retinyl palmitate in fortified milks, flours (wheat, maize), and sugar. METHODS: The portable fluorometer was assessed in a three-step procedure to determine its working range and linearity, intra-assay precision, and interperson precision. Measurements were compared with the results obtained by high-performance liquid chromatography (HPLC), commonly regarded as the standard method for vitamin A analysis. RESULTS: The portable fluorometer (iCheck FLUORO) and its test kit vials (iEx Mila) precisely determined the vitamin A contents in fortifed flours, sugar, and milks. Its working range was 1 to 10, 0.5 to 3.0, and 5 to 15 mg retinol equivalents (RE) kg(-1) for flours (wheat and corn), milks, and sugar, respectively; these values are in accordance with the World Health Organization recommendations for food fortification in least developed countries. The limits of detection are higher than those of HPLC but are all satisfactory (< 1.46 mg RE kg(-1)). The coefficients of variation within and between observers were satisfactory, especially for sugar and milk. CONCLUSIONS: The linear relationship between the data from the portable fluorometer and the HPLC data confirms that the portable fluorometer provides a good determination of the vitamin A content of the fortified products in the tested range.


Assuntos
Sacarose Alimentar/análise , Farinha/análise , Análise de Alimentos/instrumentação , Alimentos Fortificados/análise , Leite/química , Vitamina A/análise , Animais , Cromatografia Líquida de Alta Pressão , Diterpenos , Fluorometria/instrumentação , Controle de Qualidade , Ésteres de Retinil , Triticum , Vitamina A/análogos & derivados , Zea mays
4.
Int J Vitam Nutr Res ; 83(2): 122-8, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24491885

RESUMO

Vitamin A deficiency is still one of the major public health problems in least developed countries. Fortification of vegetable oils is a strategy implemented worldwide to prevent this deficiency. For a fortification program to be effective, regular monitoring is necessary to control food quality in the producing units. The reference methods for vitamin A quantification are expensive and time-consuming. A rapid method should be useful for regular assessment of vitamin A in the oil industry. A portable device was compared to high-performance liquid chromatography (HPLC) for three plant oils (rapeseed, groundnut, and soya). The device presented a good linearity from 3 to 30 mg retinol equivalents per kg (mg RE.kg- 1). Its limits of detection and quantification were 3 mg RE.kg- 1 for groundnut and rapeseed oils and 4 mg RE.kg- 1 for soya oil. The intra-assay precision ranged from 1.48 % to 3.98 %, considered satisfactory. Accuracy estimated by the root mean squares error ranged from 3.99 to 5.49 and revealed a lower precision than HPLC (0.4 to 2.25). Although it offers less precision than HPLC, the device estimates quickly the vitamin A content of the tested oils from 3 or 4 to 15 mg RE.kg- 1.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Óleos de Plantas/análise , Óleo de Soja/análise , Vitamina A/análise , Calibragem , Ácidos Graxos Monoinsaturados , Alimentos Fortificados/análise , Limite de Detecção , Óleo de Amendoim , Óleo de Brassica napus , Kit de Reagentes para Diagnóstico , Sementes/química
5.
Curr Res Food Sci ; 6: 100489, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37095831

RESUMO

The potential of drying to preserve the nutritional quality of a small freshwater fish Henicorhynchus siamensis was assessed. Drying time to reach moisture content and water activity of 10 g/100g and 0.65 ranged from 55 h at 50 °C to 20 h at 80 °C, respectively. Dried fish powder is rich in macronutrients (protein, lipid and ash) and essential minerals (calcium, phosphorus, iron and zinc) due to water removal and despite lipid loss. It is still rich in polyunsaturated fatty acids although docosahexaenoic acid was reduced except at 60°C. Vitamin A was rapidly degraded and manganese was concentrated at high level. However, mean score for the nutritional adequacy of the 15 nutrients (SAIN) and score of nutrients to limit (LIM) show that the fish powder can be used as a food ingredient for example in the formulation of fish snack or instant soup. With the abundance of Henicorhynchus siamensis, dried fish powder from this species could contribute to food security in Cambodia, especially vulnerable people in rural areas.

6.
BMJ Glob Health ; 8(12)2023 12 18.
Artigo em Inglês | MEDLINE | ID: mdl-38114237

RESUMO

Public policies often aim to improve welfare, economic injustice and reduce inequality, particularly in the social protection, labour, health and education sectors. While these policies frequently operate in silos, the education sphere can operate as a cross-sectoral link. Schools represent a unique locus, with globally hundreds of millions of children attending class every day. A high-profile policy example is school feeding, with over 400 million students worldwide receiving meals in schools. The benefits of harmonising interventions across sectors with a common delivery platform include economies of scale. Moreover, economic evaluation frameworks commonly used to assess policies rarely account for impact across sectors besides their primary intent. For example, school meals are often evaluated for their impact on nutrition, but they also have educational benefits, including increasing attendance and learning and incorporating smallholder farmers into corporate value chains. To address these gaps, we propose the introduction of a comprehensive value-for-money framework for investments toward school systems that acknowledges the return to a common delivery platform-schools-and the multisectoral returns (eg, education, health and nutrition, labour, social protection) emerging from the rollout of school-based programmes. Directly building on benefit-cost analysis methods, this framework could help identify interventions that yield the highest gains in human capital per budget expenditure, with direct implications for finance ministries. Given the detrimental impact of COVID-19 on schoolchildren and human capital, it is urgent to build back stronger and more sustainable welfare systems.


Assuntos
Instituições Acadêmicas , Estudantes , Criança , Humanos , Escolaridade , Política Pública , Análise Custo-Benefício
7.
Antioxidants (Basel) ; 11(4)2022 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-35453425

RESUMO

This review paper gives an insight into the effective delivery mechanisms for health-promoting substances and highlights the challenges of using antioxidants and bioactives in foods. The selection criteria for choosing bioactives and their extraction in bioavailable form with their adequate incorporation techniques and delivery mechanisms are covered. Moreover, an overview of existing methods for determination of bioactivity is given. The importance of scientifically evaluating the effects of foods or food components on consumer health before making claims about the healthiness is aligned. Finally, a scientific perspective on how to respond to the booming demand for health-promoting products is given, and we acknowledge that despite the work done, there are still many challenges that need to be overcome.

8.
Food Chem ; 365: 130638, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34329876

RESUMO

Crude palm oil (CPO) is extracted from the mesocarp of oil palm (Elaeis guineensis) fruits. CPO is widely consumed in many African countries. Due to its high provitamin A carotenoid content, it is also widely used in programmes designed to prevent vitamin A deficiency. Elaeis guineensis occurs naturally across a wide geographical range in Africa. We investigated the carotene, tocochromanol (vitamin E) and fatty acid composition of a large set of genotypes representative of this genetic and geographic diversity. We found considerable intraspecific diversity in most lipid traits. Populations from Côte d'Ivoire were distinguished from other origins by their very low palmitate content and high tocochromanol content. Genotypes from Benin, Côte d'Ivoire and Nigeria were characterized by high carotene contents. Finally, hybrids of crosses between genotypes from Côte d'Ivoire and Nigeria produce CPO with exceptionally high provitamin A and vitamin E contents together with low palmitate content.


Assuntos
Arecaceae , Petróleo , Arecaceae/genética , Carotenoides , Ácidos Graxos , Nigéria , Óleo de Palmeira
9.
Int J Food Sci Nutr ; 61(4): 404-16, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20113188

RESUMO

The recipes of 50 multi-ingredient dishes consumed by the population in an urban district were noted down. The nutritional value was determined as well as the cook value of the dishes in order to evaluate the severity of the thermal treatment. The recipes were simple and involved steps such as boiling, mixing, and cutting. Fibre contents were rather low except when the leaf stems were included. All the dishes had very high beta-carotene content (15.8-25.0 mg/100 g dry matter) and retinol activity equivalent (RAE) (1.3-2.3 mg RAE/100 g dry matter) because of the high proportion of fresh leafy vegetables (from 41.2% to 58.8% of the total dry matter of the ingredients). When meat was added to the preparation, the micronutrient content (iron, zinc, and retinol) was not increased significantly. In three dishes, a positive correlation was found between the thermal treatment severity and the 13-cis-beta-carotene amount.


Assuntos
Culinária , Dieta , Valor Nutritivo , Folhas de Planta/química , Verduras/química , beta Caroteno/análise , Pré-Escolar , Fibras na Dieta , Humanos , Lactente , Madagáscar , Carne , Micronutrientes , População Urbana , Vitamina A
10.
Food Chem X ; 5: 100076, 2020 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-31891158

RESUMO

Flour fortification with folic acid (FA) is implemented in many countries, and the fortification of flour with vitamin B12 has been planned. However, vitamins losses can occur during storage. In this study, fortified wheat flour was packaged either in paper bags or multilayer aluminum/PET bags, and stored in controlled conditions of temperature (25 °C or 40 °C) and relative humidity (65% or 85% RH) for 6 months. FA content, cyanocobalamin content, and microbial quality were regularly assessed. In flours packed in multilayer bags (non-permeable to oxygen and humidity), no significant FA and cyanocobalamin losses were observed, irrespective of temperature and RH. In flours packed in permeable paper bags, the microbial quality deteriorated in flours stored at 85% RH, FA loss reached 22-53% after 6 months at 85% RH, whereas cyanocobalamin loss reached 49-63% after 6 months at 65% RH. This shows that, depending on environmental conditions, packaging choice is of critical importance.

11.
Food Chem ; 240: 43-50, 2018 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-28946293

RESUMO

Micronutrient deficiencies result in irreversible physical and cognitive consequences. Fortification of flour is widely applied to address micronutrient deficiencies, but vitamin losses can occur during the storage of fortified products. This work aimed at assessing the combined influence of different factors on vitamin A retention and the oxidative status of wheat flours: storage duration (up to 6months), temperature during storage, relative humidity within storage facilities, type of packaging (oxygen-permeable or not), and premix composition (with or without ferrous sulphate). Vitamin A degradation was high and occurred rapidly: more than 45% was lost within 3months in the mildest conditions, whereas over 85% was lost within 3months in the most severe conditions. Vitamin A retention was related to the extent of oxidation reactions that occurred in flours during storage, and the factors that mostly affected vitamin A retention were the storage duration, the type of packaging and the temperature.


Assuntos
Farinha , Ferro/análise , Triticum , Vitamina A/análise , Zinco/análise , Armazenamento de Alimentos , Alimentos Fortificados
12.
J Agric Food Chem ; 64(8): 1695-701, 2016 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-26844382

RESUMO

Micronutrient deficiencies are still a public health issue in least developed countries. Promoting diet diversification is a promising strategy. Numerous fruits and vegetables are rich in micronutrients, but some of these compounds are poorly bioaccessible. The objective of this study was to identify the biochemical determinants of the micronutrient bioaccessibility in leaves. The contents in cell walls, pectins, tannins, and proteins of the leafy vegetables were assessed, and correlations with the micronutrient bioaccessibitity were explored. The leafy vegetables have interesting nutritional profiles with noticeable amounts in protein, provitamin A (ß-carotene), and α-tocopherol for some species. Their cell wall contents greatly varied from 3.4 to 8.7 g/100 g as well as their pectin percentages. Only the perilla and drumstick leaves contained condensed tannins. In fresh leaves, the contents in bioaccessible carotenoids were low. The correlation study highlighted that the carotenoid bioaccessibility was negatively correlated to the pectin contents of the leaves.


Assuntos
Micronutrientes/análise , Folhas de Planta/química , Verduras/química , Disponibilidade Biológica , Valor Nutritivo , Oligoelementos/análise , alfa-Tocoferol/análise , beta Caroteno/análise
13.
Syst Appl Microbiol ; 39(2): 115-21, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26776108

RESUMO

Lactic acid bacteria (LAB) synthesize a wide variety of biochemical compounds during food fermentation. Carotenoids provide important biological functions for bacteria, and their consumption by humans has many beneficial effects. In this study, the presence of several genes involved in the production of carotenoids was determined by BLAST analysis and PCR in a collection of 156 LAB isolated from traditional amylaceous African fermented foods. Only the crtE gene and the crtNM operon were present and detected in Lactobacillaceae. Most of the strains with positive PCR detection of the operon crtNM produced carotenoid-like compounds when grown in MRS broth. The carotenoids produced differed from compounds previously identified in other LAB except for one peak, which was closely related to 4,4'-diaponeurosporene already reported in the literature in Lactobacillus plantarum species. Most producing strains belonged to Lactobacillus fermentum and L. plantarum species but a few Pediococcus acidilactici were also producers. Furthermore, the most efficient L. plantarum was able to synthesize carotenoids in a cereal fermented food. Genetic screening was shown to be efficient since, in all cases, it eliminated the need for biochemical analysis of strains in which no amplicons of the operon crtNM were obtained.


Assuntos
Carotenoides/biossíntese , Genes Bacterianos , Lactobacillales/genética , Lactobacillales/metabolismo , Cromatografia Líquida de Alta Pressão , Fermentação , Microbiologia de Alimentos , Lactobacillales/classificação , Óperon , Reação em Cadeia da Polimerase
14.
Food Chem ; 184: 90-8, 2015 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-25872430

RESUMO

Food fortification is implemented to address vitamins A and D deficiencies in numerous countries. The stability of vitamins A and D3 was assessed during a two-month period reproducing the usual oil storage conditions before sale to consumers. Soybean oils with different oxidative status and vitamin E contents were stored in the dark, semi-dark, or exposed to natural light. Lipid peroxidation took place after 3 weeks of storage in dark conditions. After 2 months, the vitamin A and D3 losses reached 60-68% and 61-68%, respectively, for oils exposed to natural light, and 32-39% and 24-44% in semi-dark conditions. The determining factors of vitamin A and D3 losses were (in decreasing order) the storage time, the exposure to light and the oxidative status of the oil, whereas vitamin E content had a protective role. Improving these parameters is thus essential to make vitamins A and D fortification in oils more efficient.


Assuntos
Colecalciferol/química , Alimentos Fortificados/análise , Luz , Peroxidação de Lipídeos , Óleo de Soja/análise , Vitamina A/química , Armazenamento de Alimentos , Humanos
15.
Food Chem ; 136(2): 871-7, 2013 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-23122139

RESUMO

Vitamin A deficiency is a public health issue in developing countries and promoting dietary carotenoids as precursors is a promising strategy. However, carotenoids present in numerous fruits and vegetables are unstable and poorly bioaccessible. This study evaluated these two parameters during in vitro digestion of carotenoids and retinoids from carrot juice, raw and cooked spinach, micronutrient-fortified flour and standards without food matrix. Standards were unstable whereas vitamin A from fortified flour and native food carotenoids were generally better protected by the food matrix (30-100% remaining versus 7-30% for standards). Hydrothermal cooking did not influence spinach carotenoid digestive stability but decreased their contents, phenomenon compensated by a significantly better micellarisation from 15-fold for ß-carotene to 72-fold for lutein. Finally, carrot juice provided the greatest amount of bioaccessible provitamin A with 1850 µg/100g dry matter (DM) versus 790 and 80 µg/100g DM in cooked and raw spinach, respectively.


Assuntos
Carotenoides/química , Digestão , Vitamina A/química , Disponibilidade Biológica , Carotenoides/farmacocinética , Culinária , Daucus carota/química , Daucus carota/metabolismo , Farinha/análise , Humanos , Modelos Biológicos , Spinacia oleracea/química , Spinacia oleracea/metabolismo , Vitamina A/farmacocinética
16.
J Food Sci ; 74(5): C339-47, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19646025

RESUMO

The impact of deep-fat frying on the micronutrient content of plantain (Musa AAB"barraganete") was evaluated during processing of plantain chips called "tostones." Water content, micronutrients (potassium, L-ascorbic acid, alpha-carotene, beta-carotene) content, and the temperature within the food were quantified during the course of frying. A nonisothermal kinetics analysis of the 1st-order reaction (micronutrient degradation) induced by deep-fat frying, particularly in terms of the spatial distribution of temperature, was proposed. The kinetic parameters (pre-exponential factor k(0,) activation energy E(a)) were identified by nonlinear optimization, minimizing the residual variance between the experimental and theoretical micronutrient content. Agreement between model and experimental values was checked. During 1st and 2nd frying, potassium was well retained while carotenoid contents decreased significantly. Moreover, L-ascorbic acid contents decreased significantly, just during 2nd frying. k(0) was identified as well as E(a) observed for L-ascorbic acid, alpha-carotene, and beta-carotene as 68.4 to 71.5, 79.6 to 84.9, and 85.9 to 88.6 kJ/mol, respectively. beta-carotene appeared to be more heat-resistant than alpha-carotene and L-ascorbic acid. The behavior of the nutritional markers appears to be the consequence of the thermal and hydric histories of the crust and of the heart of the plantain disk related to heat transfer during preparation of the "tostones."


Assuntos
Manipulação de Alimentos/métodos , Temperatura Alta , Micronutrientes/análise , Plantago/química , Análise de Variância , Ácido Ascórbico/análise , Carotenoides/análise , Fenômenos Químicos , Gorduras/análise , Cinética , Potássio/análise , Água/análise
17.
Int J Food Sci Nutr ; 58(2): 108-15, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17469766

RESUMO

The diet of 200 randomly selected 1-year-old to 5-year-old children was studied in a rural area of Burkina Faso. The mothers took part in a questionnaire survey and a 24-h dietary recall to index the type and the ingested quantities of the food consumed by the child the previous day. The average percentages of the Recommended Nutrient Intake met by the consumption of a dish component per meal did not exceed 25% for energy, iron, zinc and vitamin A. With respect to their initial composition and the quantities ingested, several dish components such as starchy-based products (millet-based-tô) or sauces (red sorrel leaves, dried okra) were good sources of micronutrients in the children's diets. Several dish components were selected and their preparation observed in six households to obtain precise details of the recipe. Several ingredients (42) and unit operations (nine) were used to prepare the local foods. Cooking in water (boiling), which was the main unit operation, did not exceed 43 min and the temperature used was under 100 degrees C. Several ingredients were subjected to two or three thermal treatments and the duration of cooking reached 56 min in groundnut sauce. The most at-risk unit operations likely to decrease the nutritional quality were cooking in water followed by draining or cooking for a long time.


Assuntos
Fenômenos Fisiológicos da Nutrição Infantil , Comportamento Alimentar , Manipulação de Alimentos/métodos , Micronutrientes/análise , Burkina Faso , Pré-Escolar , Culinária/métodos , Inquéritos sobre Dietas , Feminino , Humanos , Lactente , Fenômenos Fisiológicos da Nutrição do Lactente , Ferro da Dieta/administração & dosagem , Ferro da Dieta/análise , Masculino , Estado Nutricional , Saúde da População Rural/estatística & dados numéricos , Vitamina A/administração & dosagem , Vitamina A/análise , Zinco/administração & dosagem , Zinco/análise
18.
J Food Sci ; 72(2): S153-8, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17995857

RESUMO

The effects of the formulation (okra, fish, soumbala, extract of wood ash) and cooking time of okra sauce on total iron and zinc content and on their in vitro digestibility were evaluated following a Doehlert uniform shell design with 5 factors and 33 trials. Cooking time had no significant effect on in vitro digestible iron and zinc content, whereas formulation did. Each ingredient had a specific effect. Extract of wood ash, which is a source of soluble and digestible iron and zinc, is a good way of increasing the digestible mineral content of the dish. Okra, the main ingredient in this sauce, has a negative effect and should be added in moderate quantities (< 37.7% of the DM of the sauce). An optimization using the desirability function allows us to identify the optimal recipe that enabled the quantity of digestible iron to be doubled and the quantity of digestible zinc to be increased by one third. This recipe calls for a mixture of 37.7% okra, 26.3% dried fish, 18.5% soumbala, and 3.7% extract of wood ash cooked for 25 min.


Assuntos
Culinária/métodos , Hibiscus/química , Ferro/análise , Zinco/análise , Disponibilidade Biológica , Digestão , Manipulação de Alimentos/métodos , Humanos , Ferro da Dieta/análise , Valor Nutritivo , Temperatura , Fatores de Tempo
19.
Int J Food Sci Nutr ; 57(1-2): 123-36, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16849120

RESUMO

The influence of thermal treatment (frying of plantain) on the micronutrients ascorbic acid, potassium and carotenoids is evaluated. Cylinders (diameter 30 mm, thickness 10 mm) of plantain (Musa AAB 'barraganete') were fried at four thermal treatments (120-180 degrees C and from 24 to 4 min) to obtain products with approximately the same water content (approximately 0.8+/-0.02 kg/kg1) and fat content (approximately 0.15+/-0.06 kg/kg). The thermal study used the cook value and the mean cook value as indicators of the effect of several different treatment temperatures and times on quality. Deep-fat frying had no significant effect on carotenoid contents at any frying conditions, and on potassium content, except at 120 degrees C and 24 min (loss

Assuntos
Ácido Ascórbico/análise , Carotenoides/análise , Culinária/métodos , Plantago/química , Potássio na Dieta/análise , Gorduras na Dieta/análise , Análise de Alimentos/métodos , Temperatura Alta , Valor Nutritivo , Temperatura , Água/análise
20.
Curr Microbiol ; 47(2): 113-8, 2003 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-14506857

RESUMO

Penicillium funiculosum Thom. was consistently isolated from pineapple-infected fruitlet (black spots). Polyphenol oxidase, peroxidase, and laccase activities were determined in extracts from contiguous and infected fruitlets. Healthy fruitlets showed a rather high level of polyphenol oxidase (optimum pH 7.0), and this activity was tremendously increased (X 10) in contiguous infected fruitlets. Furthermore, infected fruitlets also exhibited laccase activity (optimum pH 4.0), while peroxidase was rather constant in both fruitlets. Browning reactions were attributed to qualitative and quantitative modifications of the enzymatic equipment (polyphenol oxidase and laccase) (p < 0.0001). In infected fruiltets, sucrose and L-malic acid were present at significantly lower amounts than in healthy ones, likely owing to fungal metabolism (p < 0.0001), whereas cell wall material was three times higher, which could be viewed as a defense mechanism to limit expansion of the mycelium.


Assuntos
Ananas , Penicillium/patogenicidade , Ananas/enzimologia , Ananas/metabolismo , Ananas/microbiologia , Catecol Oxidase/metabolismo , Lacase , Malatos/metabolismo , Oxirredutases/metabolismo , Penicillium/classificação , Peroxidase/metabolismo , Doenças das Plantas/microbiologia , Sacarose/metabolismo
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