Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 19 de 19
Filtrar
Mais filtros










Intervalo de ano de publicação
1.
Toxins (Basel) ; 15(10)2023 10 08.
Artigo em Inglês | MEDLINE | ID: mdl-37888635

RESUMO

An adsorbent material derived from alfalfa leaves was prepared and further characterized, and its efficacy for removing aflatoxin B1 (AFB1) was investigated. Characterization consisted of the use of attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR), environmental scanning electron microscopy (ESEM), X-ray fluorescence spectroscopy (XRF), X-ray diffraction (XRD), point of zero charge (pHpzc), zeta potential (ζ-potential), UV-Vis diffuse reflectance spectroscopy, and spectral analysis. To determine the adsorption capacity against AFB1 (250 ng AFB1/mL), pH-dependent and avian intestinal in vitro models were used. The adsorbent inclusion percentage was 0.5% (w/w). In general, the pH-dependent model gave adsorption percentages of 98.2%, 99.9%, and 98.2%, evaluated at pH values of 2, 5, and 7, respectively. However, when the avian intestinal model was used, it was observed that the adsorption percentage of AFB1 significantly decreased (88.8%). Based on the characterization results, it is proposed that electrostatic, non-electrostatic, and the formation of chlorophyll-AFB1 complexes were the main mechanisms for AFB1 adsorption. From these results, it can be concluded that the adsorbent derived from alfalfa leaves could be used as an effective material for removing AFB1 in in vitro digestion models that mimic the physiological reality.


Assuntos
Aflatoxina B1 , Medicago sativa , Aflatoxina B1/química , Modelos Teóricos , Adsorção
2.
J Food Sci ; 88(11): 4472-4482, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37799063

RESUMO

Tamales are a traditional dish rich in fat and carbohydrates with increasing popularity. The present study aimed to investigate the use of agave inulin powder (AIP) as a potential fat replacer in tamales. The effect of replacing 0%, 33%, 66%, and 100% (w/w) of fat with AIP was evaluated in the physicochemical, sensory, and nutritional features of tamales. The fat content of tamales decreased up to 88% in AIP tamales, whereas total dietary fiber (TDF) increased up to 14%. TDF in AIP tamales had a higher proportion of soluble dietary fiber (SDF). Moreover, results indicated that both insoluble and SDF were formed during the processing of tamales. Fat replacement led to a reduction of up to 26% in the calorie load of tamales. Fourier transform infrared spectroscopy analysis confirmed changes in the absorption bands related to carbohydrates, with increments in peaks associated with inulin (936 and 862 cm-1 ), and inhibition of retrogradation when inulin was included. AIP addition resulted in tamales with lighter color. Fat replacement with AIP affected the texture of tamales increasing their softness, adhesiveness, and cohesiveness. In general, inulin positively affected the hedonic attributes and acceptance of tamales. Interestingly, full-fat tamales had a lower glycemic index and presented higher contents of resistant starch compared to tamales with AIP. Nevertheless, agave inulin may serve as a fat replacer yielding reduced-fat tamales with higher TDF and SDF and yielding a lower calorie load without significantly affecting the sensory acceptability of this traditional meal.


Assuntos
Agave , Substitutos da Gordura , Inulina/análise , Substitutos da Gordura/análise , Fibras na Dieta/análise , Índice Glicêmico
3.
Foods ; 12(18)2023 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-37761036

RESUMO

The nixtamalization process used for tortilla production entails extended processing time and generates pollutant effluents. Ohmic heating (OH) is an emerging technology that uses an alternating electric current for rapid and uniform food heating and mitigates effluent concerns. However, gaps exist in nutrient bioavailability studies. In this work, we assessed OH's impact on tortilla nutritional value, protein, and calcium using a rat model. Twenty-five male Wistar rats were fed one of four diets for 21 days: raw corn (RC) as an experimental control, OH-processed tortillas (OHTs), traditionally processed tortillas (TPTs), commercial tortillas (CTs), and a casein diet (CD) as a growth control. Despite similar protein and macronutrient profiles, OH significantly enhanced insoluble fiber content. The weight gain sequence was OHTs > TPTs > CTs > RC. OHTs exhibited superior protein digestibility (88.52%), which was 3% higher than other diets. The serum albumin (2.63-2.73 g/dL) indicated moderate malnutrition due to the tortilla's lower protein content. Nonetheless, the protein efficiency ratio (1.2-1.74) showed no significant difference from TPTs. Bone characteristics and fracture strength resembled the tortilla-fed groups, surpassing RC. X-ray diffraction and scanning electron microscopy confirmed that the OHT and TPT diets improved male rat bone thickness and crystallinity. The findings suggest the potential for OH as an eco-friendly tortilla production method, maintaining nutritional value comparable to traditional methods.

4.
Foods ; 12(4)2023 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-36832883

RESUMO

The viscoelastic properties of cereal kernels are strongly related to their quality, which can be applied to the development of a more selective and objective classification process. In this study, the association between the biophysical and viscoelastic properties of wheat, rye, and triticale kernels was investigated at different moisture contents (12% and 16%). A uniaxial compression test was performed under a small strain (5%), and the increase in viscoelasticity at 16% moisture content corresponded to proportional increases in biophysical properties such as the appearance and geometry. The biophysical and viscoelastic behaviors of triticale were between those of wheat and rye. A multivariate analysis showed that the appearance and geometric properties significantly influenced kernel features. The maximum force showed strong correlations with all viscoelastic properties, and it can be used to distinguish between cereal types and moisture contents. A principal component analysis was performed to discriminate the effect of the moisture content on different types of cereals and to evaluate the biophysical and viscoelastic properties. The uniaxial compression test under a small strain and the multivariate analysis can be considered a simple and non-destructive tool for assessing the quality of intact cereal kernels.

5.
Toxins (Basel) ; 15(2)2023 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-36828398

RESUMO

Vermicompost was used for humic acid (HA) preparation, and the adsorption of aflatoxin B1 (AFB1) was investigated. Two forms of HA were evaluated, natural HA and sodium-free HA (SFHA). As a reference, a non-commercial zeolitic material was employed. The adsorbents were characterized by attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR), energy-dispersive X-ray spectroscopy (EDS), zeta potential (ζ-potential), scanning electron microscopy (SEM), and point of zero charge (pHpzc). The adsorbent capacity of the materials when added to an AFB1-contaminated diet (100 µg AFB1/kg) was evaluated using an in vitro model that simulates the digestive tract of chickens. Characterization results revealed the primary functional groups in HA and SFHA were carboxyl and phenol. Furthermore, adsorbents have a highly negative ζ-potential at the three simulated pH values. Therefore, it appears the main influencing factors for AFB1 adsorption are electrostatic interactions and hydrogen bonding. Moreover, the bioavailability of AFB1 in the intestinal section was dramatically decreased when sorbents were added to the diet (0.2%, w/w). The highest AFB1 adsorption percentages using HA and SFHA were 97.6% and 99.7%, respectively. The zeolitic material had a considerable adsorption (81.5%). From these results, it can be concluded that HA and SFHA from vermicompost could be used as potential adsorbents to remove AFB1 from contaminated feeds.


Assuntos
Aflatoxina B1 , Zeolitas , Animais , Aflatoxina B1/química , Aves Domésticas , Substâncias Húmicas , Galinhas , Adsorção , Zeolitas/química
6.
Curr Res Food Sci ; 5: 807-812, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35600537

RESUMO

Sorghum (Sorghum bicolor) is a nutritional grain considered an important source of micro- and macro-nutrients. Also, the flour obtained from sorghum is considered a suitable substitute for wheat flour for celiac disease patients due it is gluten-free. However, its use has some limitations due to anti-nutritional factors such as tannins, phytates, trypsin inhibitors, and protein crosslinkers. To prevent those effects, new strategies for sorghum processing have been explored. Germination of this grain has been shown to increase nutrient content further and reduce anti-nutrients. In addition, fermentation with lactic acid bacteria could modify starch and protein digestion in sorghum flour and increase their nutrient availability. Although there are many benefits to germination and fermentation, more research must be done to improve the products' texture and sensory properties to gain wider consumer acceptance. In this review, the mechanism behind changes in the nutritional and anti-nutritional profile of sorghum grain due to germination and fermentation treatments is shown, and the impact of these changes on dough rheological properties and bread quality.

7.
Acta Sci Pol Technol Aliment ; 21(1): 91-99, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35174691

RESUMO

BACKGROUND: Microwave heating may affect some non-starch polysaccharides of cereal kernels. This microwave effect can be positive for functional properties and the final product. Therefore, the purpose of this work was to explore the effects of microwave heating on mechanical properties, malt extract yield, wort viscosity, β-glucan of wort, and soluble, insoluble, and total dietary fiber in malting and feed barley. METHODS: The barley kernels were microwave heated for 4 and 8 s and compared with a control (0 s) with no microwave irradiation treatment. The mechanical properties were measured by compressive loadings; an Environmental Scanning Electron Microscopy was used for kernel layers. β-glucan content in the barley kernel and wort was measured with a Mixed Linkage beta-glucan (K-BGLU Megazyme International; Wicklow, Ireland). Insoluble, soluble, and total dietary fiber was determined using 32-07 of AACC method. RESULTS: The thickness of barley kernel bran layers was related to the mechanical properties. The modulus of elasticity decreased after 4 s of heating but increased after 8 s. Irradiation affected non-starch polysaccharides, such as β-glucan and fiber. β-glucan decreased after 4 s as did wort viscosity. The insoluble and total dietary fiber followed the same trend as β-glucan, but the soluble fiber content increased with prolonged microwave heating. CONCLUSIONS: A few seconds of microwave heating is enough to increase barley’s value in the brewing industry and improve health benefits due to minor changes in the biochemical grain components.


Assuntos
Hordeum , beta-Glucanas , Fibras na Dieta , Calefação , Hordeum/química , Micro-Ondas , beta-Glucanas/química
8.
Microorganisms ; 11(1)2022 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-36677402

RESUMO

The use of sourdough for bread production involves fermentation, which is dominated by lactic acid bacteria (LAB) and yeast. Sourdough can be inoculated with a starter culture or through a food matrix containing microorganisms to initiate sourdough fermentation. Sourdough is used as leavening agent for bread making, and metabolites produced by LAB and yeast confer a specific aroma and flavor profile to bread, thus improving its sensory attributes. However, few publications report the effect of microorganisms from different food products and by-products on sourdough fermentation. This review focuses on using different starter cultures from various food sources, from wheat flour to starter cultures. Additionally, included are the types of sourdough, the sourdough fermentation process, and the biochemical transformations that take place during the sourdough fermentation process.

9.
Int J Anal Chem ; 2021: 5540543, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34221019

RESUMO

Chia (Salvia hispanica L.) seeds contain antioxidants with great benefits for health and are widely used in the food industry. Antioxidants can be degraded by environmental factors, decreasing their biological activity. Their encapsulation in chitosan (CH) particles represents an alternative to protect them and increases their application. The encapsulation efficiency (%EE) of the antioxidants in the CH particles depends on the synthesis conditions. In this study, two methods for encapsulation of chia extract in chitosan particles were evaluated: method A, 0.05% CH in 1% acetic acid was mixed with 0.07% of tripolyphosphate (TPP) and method B, 0.3% CH in 2% acetic acid was mixed with 1% TPP. The results showed that the %EE decreased with the concentration of the extract, and the FTIR analysis suggested that the compounds of the extract were adsorbed on the surface of the particles. Dynamic light scattering and zeta potential analysis showed that the particles of method A are unstable and with a tendency to agglomerate, and the particles of method B are stable. The highest %EE was obtained with 0.2 mg·mL-1 (method A) and 1.0 mg·mL-1 (method B) of the extract. The higher loading capacity (%LC) (16-72%) was exhibited by the particles of method A. The best particle yield (62-69%) was observed for method B. The particles with the extract adsorbed showed antioxidant activity (5-60%) at 25°C; however, in the particles with the extract encapsulated, the activity increased after subjecting to acidic conditions at 40°C due to the breakdown of the particles. The results obtained will allow choosing the appropriate conditions for the synthesis of chitosan particles loaded with chia extracts with specific characteristics (%EE, %LC, size, and type) according to their future applications. The particles could be used in food and pharmaceutical industries and even in edible films for food packaging.

10.
Ultrason Sonochem ; 70: 105290, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32769043

RESUMO

The aim of this study was to evaluate thermosonication as an alternative method for the pasteurization of pulque in order to improve its shelf life and retain its quality parameters. Thermosonication was carried out at 50 °C using amplitudes of 75% (for 6 and for 9 min), 85% (for 4 and for 6 min), and 95% (for 3 and for 5 min). These were the optimal conditions found for processing pulque by thermosonication. Physicochemical (acidity, color, alcohol content, and sensory analysis) and microbiological (lactic acid bacteria and yeasts) parameters were determined during 30 days for storage at 4 ± 1 °C. Conventional pasteurization (63 °C, 30 min) and raw pulque were used as controls. According to the results, the shelf life of pulque was extended up to 24 days storage at 4 °C. After this time, the quality of beverage decreased, due that the microbial load increases. Thermosonication treatments at 75% and 85% showed a higher content of LAB (6.58-6.77 log CFU/mL) and yeasts (7.08-7.27 log CFU/mL) than conventional pasteurization (3.64 log CFU/mL of LAB and 3.97 log CFU/mL of yeasts) at 24 days of storage. Raw pulque demonstrated up to 7.77 log CFU/mL of yeasts and 7.51 log CFU/mL of LAB. Pulque processed by thermosonication exhibited greater lightness, sensory acceptance, a maximal acidity of 0.83 g/lactic acid, and an alcohol content of 4.48-4.95% v/v. The thermosonication process preserves sensory and physicochemical properties better than conventional pasteurization. Lactic acid bacteria such as Lactobacillus kefiri, Lactobacillus acidophilus, and Lactobacillus hilgardii and yeasts such as Saccharomyces cereviasiae were identified in thermosonicated pulque.


Assuntos
Bebidas , Alimentos Fermentados , Sonicação/métodos , Temperatura , Contagem de Colônia Microbiana , Lactobacillus/isolamento & purificação , Lactobacillus/metabolismo , Lactobacillus/ultraestrutura , México , Microscopia Eletrônica de Varredura , Leveduras/isolamento & purificação , Leveduras/metabolismo , Leveduras/ultraestrutura
11.
J Food Sci ; 84(12): 3653-3663, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31750939

RESUMO

This research aimed to evaluate the effect of different calcium compounds and their concentration on the viscoelastic parameters of flours and tortillas obtained with traditional and ecological nixtamalization. Specimens (tablets) of nixtamalized flours and tortillas (14% moisture) prepared with three different calcium sources and four concentrations were sintered using a die and a hydraulic press and were evaluated by stress-relaxation tests with a texturometer. Data collected from the stress-relaxation curve were fitted into a three-element generalized Maxwell model (r2 = 0.9999), allowing the detection of significant differences in the estimated viscoelastic parameters. When flours are processed into tortillas, the most notable change was the increase of +88.44% and +73.44%, respectively, in the summation of the elastic modulus, and the compressional viscosity in samples produced with CaCO3. On the contrary, tablets from samples with Ca(OH)2 presented a sharp diminishing (loss) in both of the evaluated viscoelastic parameters, accounting a decrease of -39.82% and -46.28% for the elastic modulus and compressional viscosity summations, respectively. Highly significant correlations were found among viscoelastic parameters when a slight proportional increase was observed in the specific elastic moduli, meaning that the energy was stored by each elastic element in the tablets, while the compressional viscosity coefficients varied as a function of time. Finally, it was found that the residual spring due to the pure elastic component (E0 ) stored energy during the entire test. PRACTICAL APPLICATION: There is no published information about a simple methodology for the evaluation of the viscoelastic properties of dry nixtamalized flours (powder) with a texturometer. The method proposed was sensitive and accurate, since it was capable of detecting differences among samples processed under distinct processing factors conditions. The study of viscoelastic properties of grain foods contributes to the construction of molecular theories occurring in their chemical compounds, which is strongly related to food texture. Those theories are handy to improve nutritional and textural properties of grain foods and are essential to powder handling, processing, and transportation, which allows the processing factors optimization.


Assuntos
Pão/análise , Compostos de Cálcio/análise , Farinha/análise , Elasticidade , Manipulação de Alimentos , Minerais/análise , Comprimidos/química , Viscosidade , Zea mays/química
12.
Food Sci Biotechnol ; 28(4): 975-982, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31275697

RESUMO

Acrylamide can be generated from food components during tortilla chips frying. Thus, the aim of this research was to study different nixtamalization processes as traditional (TNP) with lime [Ca(OH)2], ecological (ENP) with CaCO3, classic nixtamalization (CNP) that uses wood ash and extrusion (EXT) with no Ca+2 source on mitigating the acrylamide formation in deep-fat frying tortilla chips. Acrylamide quantification was done through HPLC-UV. Lower acrylamide content in tortilla chips was for CNP with 46.3 µg/kg, followed by TNP with 55.0 µg/kg, ENP with 694.6 µg/kg and EXP with 1443.4 µg/kg. Differences in acrylamide values among samples can be related to effect of cations (Ca2+, Mg2+, Fe2+, Zn2+, Na+ and K+) present in wood ashes, lime and salts used as raw materials. Correlation of (r = 0.85; p <0.0005) was observed in color of tortilla chips, moisture, texture, blisters, and oil with acrylamide. Nixtamalization process is an effective and inexpensive strategy for acrylamide mitigation.

13.
Antioxidants (Basel) ; 7(7)2018 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-29949924

RESUMO

The objective of this work was to determine the concentration of total phenols, total flavonoids, hydroxycinnamic acids, and proanthocyanidins present in crude extracts of Quercus laurina, Q. crassifolia, and Q. scytophylla bark. They were extracted by ethanol (90%) maceration and hot water. The antioxidant capacity was determined by the ability to capture OH•, O2•−, ROO•, H2O2, NO•, and HClO. The hot water crude extract of Q. crassifolia was chosen to be concentrated and purified due to its higher extraction yield (20.04%), concentration of phenol compounds (747 mg gallic acid equivalent (GAE)/g, 25.4 mg quercetin equivalent (QE)/g, 235 mg ChAE/g, 25.7 mg chlorogenic acid equivalents (ChAE)/g), and antioxidant capacity (expressed as half maximal effective concentration (EC50, µg/mL): OH• = 918, O2•− = 80.5, ROO• = 577, H2O2 = 597, NO• ≥ 4000, HClO = 740). In a second stage, Q. crassifolia extracted with hot water was treated with ethyl acetate, concentrating the phenol compounds (860 mg GAE/g, 43.6 mg QE/g, 362 ChAE/g, 9.4 cyanidin chloride equivalents (CChE)/g) and improving the scavenging capacity (OH• = 467, O2•− = 58.1, ROO• = 716, H2O2 = 22.0, NO• ≥ 4000, HClO = 108). Q. crassifolia had the highest polyphenolic concentration and the better capacity for scavenging reactive species, being a favorable candidate to be considered in the development of new products.

14.
Food Chem ; 248: 21-28, 2018 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-29329845

RESUMO

The viscoelastic characteristics of nixtamalized corn masa were assessed by the dynamic oscillatory test. Masa samples were prepared with flours obtained by nixtamalization with different calcium sources: Ca(OH)2 (traditional), wood ashes (classic), CaCO3 (ecological), CaSO4 (ecological), CaCl2 (ecological), and Ca(C2H5COO)2 (ecological). A sample cooking without calcium source was used as control. Storage (G') and loss (G'') moduli were higher in masa from traditional and classic processes indicating a more elastic and viscous masa. Masa of flours from CaCl2 and Ca(C2H5COO)2 had the lowest values of G' and G''. Viscoelastic properties were explained in terms of the degree of starch gelatinization, the hydrolysis of pericarp and fibre content, the calcium-starch and calcium-zein interactions, as well as the presence of amylose-lipid complexes. Nixtamalization with Ca(OH)2 and wood ashes gave the best viscoelastic characteristics of masa.


Assuntos
Cálcio/química , Culinária , Farinha , Zea mays/química , Amilose/química , Farinha/análise , Amido/química , Viscosidade
15.
Food Chem ; 240: 456-462, 2018 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-28946298

RESUMO

The aim of this work was to study the effect of three nixtamalization processes using wood ashes, Ca(OH)2, and CaCl2 on the physicochemical properties of beans. Raw beans had C-type starch, 10.10% resistant starch (RS), and two DSC endotherms: 1) starch gelatinization, and 2) melting of amylose-lipid complexes plus protein denaturation. Nixtamalization increased the Ca and Fe content, decreased the RS content to 4.19-4.43%, and produced starch retrogradation. DSC and FT-IR analysis of the flours evidenced a "stabilizing" effect of cooking with NaCl and CaCl2 on bean proteins. In contrast, cooking with wood ashes and Ca(OH)2 produced denaturation of bean proteins, decreasing the second transition enthalpy and absorption bands of amide I, II and III. Results showed that traditional and classic nixtamalization of beans are alternatives to obtaining mineral fortified flours that could be used as ingredients in the elaboration of foods with a good nutritional profile.


Assuntos
Phaseolus , Amilose , Fenômenos Químicos , Farinha , Espectroscopia de Infravermelho com Transformada de Fourier , Amido
16.
J Sci Food Agric ; 97(4): 1235-1243, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27322412

RESUMO

BACKGROUND: The aim of this research was to evaluate the visco-elastic properties of conditioned wheat kernels and their doughs by applying the compression test under a small strain. Conditioned wheat kernels and their doughs, from soft and hard wheat classes were evaluated for total work (Wt ), elastic work (We ) and plastic work (Wp ). RESULTS: Soft wheat kernels showed lower We than Wp , while the hard wheat kernels had a We that was higher than Wp . Regarding dough visco-elasticity, cultivars from soft and hard wheat showed higher Wp than We . The degree of elasticity (DE%) of the conditioned wheat kernel related to its dough decreased ∼46% in both wheat classes. The Wt , We and Wp from the soft wheat kernel and dough correlated with physico-chemical and farinographic flour tests. The Wt , Wp and the maximum compression force (Fmax ) of the dough from hard wheat class presented highly significant negative correlations with wet gluten. CONCLUSION: The visco-elasticity parameters from compression test presented significant differences among conditioned wheat classes and their doughs. © 2016 Society of Chemical Industry.


Assuntos
Grão Comestível , Farinha/análise , Manipulação de Alimentos/métodos , Reologia , Estresse Mecânico , Triticum , Água , Pão , Elasticidade , Glutens/análise , Humanos , Especificidade da Espécie , Triticum/classificação , Viscosidade
17.
Molecules ; 19(12): 21066-84, 2014 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-25517344

RESUMO

Extrusion is an alternative technology for the production of nixtamalized products. The aim of this study was to obtain an expanded nixtamalized snack with whole blue corn and using the extrusion process, to preserve the highest possible total anthocyanin content, intense blue/purple coloration (color b) and the highest expansion index. A central composite experimental design was used. The extrusion process factors were: feed moisture (FM, 15%-23%), calcium hydroxide concentration (CHC, 0%-0.25%) and final extruder temperature (T, 110-150 °C). The chemical and physical properties evaluated in the extrudates were moisture content (MC, %), total anthocyanins (TA, mg·kg(-1)), pH, color (L, a, b) and expansion index (EI). ANOVA and surface response methodology were applied to evaluate the effects of the extrusion factors. FM and T significantly affected the response variables. An optimization step was performed by overlaying three contour plots to predict the best combination region. The extrudates were obtained under the following optimum factors: FM (%) = 16.94, CHC (%) = 0.095 and T (°C) = 141.89. The predicted extrusion processing factors were highly accurate, yielding an expanded nixtamalized snack with 158.87 mg·kg(-1) TA (estimated: 160 mg·kg(-1)), an EI of 3.19 (estimated: 2.66), and color parameter b of -0.44 (estimated: 0.10).


Assuntos
Antocianinas/química , Manipulação de Alimentos , Lanches , Zea mays/química , Antocianinas/isolamento & purificação , Hidróxido de Cálcio/química , Pigmentação , Temperatura
18.
Plant Foods Hum Nutr ; 67(4): 442-9, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23230010

RESUMO

Nixtamalization process is the first step to obtain maize based products, like tortillas; however, in both the traditional and commercial processes, white grain is generally preferred. Creole maize races, mainly pigmented varieties, have increasingly attention since these are rich in anthocyanins and carotenoids. The aim of this investigation was to evaluate the antioxidant and antimutagenic activity of rich anthocyanins and carotenoids extracts from creole maize races before (grain) and after (masa and tortilla) the nixtamalization process. Most anthocyanins and carotenoids were lost during nixtamalization. Before nixtamalization, blue and red genotypes contained either higher antioxidant capacity and anthocyanin contents (963 ± 10.0 and 212.36 ± 0.36 mg of cyanidin-3-glucoside eq/100 g, respectively) than the white and yellow genotypes. However, the highest carotenoid levels were displayed by red grains (1.01 ± 0.07 to 1.14 ± 0.08 µg of ß-carotene eq/g extract). Anthocyanins losses were observed when the blue grains were processed into masa (83 %) and tortillas (64 %). Anthocyanins content correlated with antiradical activity (r = 0.57) and with 2-aminoanthracene -induced mutagenicity inhibition on TA98 and TA100 (r = -0.62 and r = -0.44, respectively). For white grains, nixtamalization also reduced carotenoids (53 to 56 %), but not antioxidant activity and 2-Aa-induced mutagenicity. Throughout the nixtamalization process steps, all the extracts showed antimutagenic activity against 2-aminoanthracene-induced mutagenicity (23 to 90 %), displaying higher potential to inhibit base changes mutations than frameshift mutations in the genome of the tasted microorganism (TA100 and TA98, respectively). The results suggest that even though there were pigment losses, creole maize pigments show antioxidant and antimutagenic activities after nixtamalization process.


Assuntos
Antocianinas/metabolismo , Antimutagênicos/metabolismo , Antioxidantes/metabolismo , Carotenoides/metabolismo , Salmonella typhimurium/fisiologia , Zea mays/química , Antocianinas/análise , Antimutagênicos/análise , Antioxidantes/análise , Carotenoides/análise , Grão Comestível/química , Manipulação de Alimentos , Genótipo , Pigmentos Biológicos , Salmonella typhimurium/efeitos dos fármacos , Especificidade da Espécie
19.
Arch. latinoam. nutr ; 46(4): 315-9, dic. 1996. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-217595

RESUMO

Se evaluaron los cambios ocurridos en algunos componentes químicos de carácter nutricional (proteína, fibra dietaria total, vitaminas hidrosolubles, lisina, triptofano estracto etéreo y ácidos grasos), de tortillas preparadas con harina integral obtenidas por un experimental de extrusión contínua (proceso CINVESTAV) comparadas con tortillas obtenidas por el proceso tradicional de nixtamalización y maíz crudo. El contenido de proteína de las tortillas obtenidas por los procesos de extrusión y tradicional, fue similar al de maíz crudo; sin embargo, en las tortillas de nixtamal se observó el menor valor de este componenete. Los contenidos de fibra dietaria total y lisina disponible de las tortillas experimentales obtenidas por extrusión mostraron mayores valores (p<0,05) en relación a las tortillas del proceso tradicional. Las tortillas de ambos procesos presentaron pérdidas de vitaminas hidrosolubles, con respecto a sus respectivos maíces sin procesar. La disminución de los niveles de proteína, triptófano y vitamina en las tortillas tradicionales de nixtamal con respecto al maíz crudo, es atribuida a la pérdida de pericarpio, capas de aleurona y otras partículas solubles durante el proceso. El tratamiento térmico en ambos procesos (tradicional y CINVESTAV) disminuyó el contenido de extracto etéreo y ácidos grasos. Las tortillas obtenidas por el proceso de extrusión CINVESTAV, presentaron mejores características nutricionales en los componentes evaluados que las obtenidas por el proceso tradicional de nixtamalización


Assuntos
Humanos , Masculino , Feminino , Farinha/análise , Farinha/estatística & dados numéricos , Zea mays , Ciências da Nutrição
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...