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1.
J Sci Food Agric ; 100(4): 1702-1710, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31803935

RESUMO

BACKGROUND: The presence of insoluble calcium oxalate druse crystals (CaOx) in sweet potato (Ipomoea batatas) can negatively affect its nutritional quality. Photosynthesis, starch, and protein composition are linked with oxalate synthesis and tuber quality under water scarcity. Our main objective was the oxalate quantitation of sweet potato tubers and shoots and also to assess how drought changes their nutritional value. Eight sweet potato accessions from Madeira, the Canaries and Guinea-Bissau were analyzed for their response to drought stress. Tubers and shoots were analyzed for total (T-Ox), soluble (S-Ox) and insoluble (CaOx) oxalates, protein, chlorophyll content index (CCI), soluble starch, starch swelling power, and starch solubility in water. RESULTS: The S-Ox and CaOx content was higher in shoots. Six accessions were above maximum CaOx levels for raw consumption. Accessions with more favorable responses to drought had decreased CaOx with S-Ox increase content for osmoregulation. They also presented slightly decreased CCI and protein contents. These accessions also had an increased shoot starch content, for further tuber storage starch hydrolysis, and maintained the quality and functional properties of the tuber starch grain. Those with a less favorable response to drought had a higher T-Ox and CaOx content in both organs, hindering water absorption. They also had decreased protein and CCI, with a slight increase in tuber starch hydrolysis. CONCLUSION: Oxalate content was significantly related to carbohydrate metabolism, CCI, and protein synthesis. This study significantly contributed to the screening of the sweet potato stress response to drought, to adapt this crop to climatic change through breeding programs. © 2019 Society of Chemical Industry.


Assuntos
Ipomoea batatas/metabolismo , Oxalatos/química , Tubérculos/química , Água/metabolismo , Metabolismo dos Carboidratos , Secas , Ipomoea batatas/química , Oxalatos/metabolismo , Fotossíntese , Brotos de Planta/química , Brotos de Planta/metabolismo , Tubérculos/metabolismo , Amido/análise , Amido/metabolismo , Água/análise
2.
Food Chem ; 309: 125585, 2020 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-31708344

RESUMO

Seed samples from 117 genetically diverse pea breeding lines were used to determine the robustness of Fourier transform mid-infrared spectroscopy (FT-MIR) for the rapid nutritional profiling of seeds. The FT-MIR results were compared to wet chemistry methods for assessing the concentrations of total protein, starch, fiber, phytic acid, and carotenoids in pea seed samples. Of the five partial least square regression models (PLSR) developed, protein, fiber and phytic acid concentrations predicted by the models exhibited correlation coefficients greater than 0.83 when compared with data obtained using the wet chemistry methods for both the calibration and validation sets. The starch PLSR model had a correlation greater than 0.75, and carotenoids had correlation of 0.71 for the validation sets. The methods implemented in this research show the novelty and usefulness of FT-MIR as a simple, fast, and cost-effective technique to determine multiple seed constituents simultaneously.


Assuntos
Ervilhas/química , Sementes/química , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Carboidratos/análise , Carotenoides/análise , Análise de Alimentos , Ácido Fítico/análise , Proteínas de Plantas/análise , Amido/análise
3.
Food Chem ; 303: 125402, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31470273

RESUMO

Chickpea is one the most important legumes consumed all around the world because of high protein content. The current study was conducted to investigate the effects of irrigation treatments at different physiological growth stages (before flowering, beginning of flowering, pod-set and pod-fill periods) on nutritional attributes of chickpea. The findings showed that one or two irrigations at different physiological growth stages instead of full irrigation treatment might be sufficient to improve the nutritional attributes of chickpea. Flowering and pod-fill periods were identified as the critical periods for irrigations and affected the nutritional component levels. The greatest protein level (29.52%) was obtained from the samples irrigated before flowering while the greatest total starch (36.30%) was obtained from the samples irrigated at the beginning of flowering. It was concluded based on present findings that physiological growth stages should be taken into consideration in irrigation practices of chickpea farming.


Assuntos
Cicer/química , Cicer/crescimento & desenvolvimento , Irrigação Agrícola , Cicer/metabolismo , Grão Comestível/química , Grão Comestível/crescimento & desenvolvimento , Grão Comestível/metabolismo , Valor Nutritivo , Proteínas de Plantas/análise , Proteínas de Plantas/metabolismo , Amido/análise , Amido/metabolismo , Água/metabolismo
4.
Food Chem ; 304: 125432, 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-31493704

RESUMO

Early indica rice starch can only be modified to a small extent by annealing treatment (ANN), which limits its application. Microwave pretreatment (MW) with different intensity was used to enhance the effectiveness of ANN, and single ANN or MW treatments were used as controls. MW pretreatments per se exhibited insignificant or minor effect on the starch. However, MW pretreatment with appropriate intensity could significantly promote the structural and physicochemical modification of the starch in subsequent ANN, including the enhancement of long- and short-range crystalline structures, the increases in gelatinization enthalpy, particle size, peak viscosity, breakdown and G' value, and the decreases in tan δ value. The MW pretreatment could untangle the entanglements between starch chains by inducing violent movement of the chains, which facilitated the molecular rearrangement and interaction during subsequent ANN, thereby promoting the structural and physicochemical changes. This study provided new insights into the annealing mechanism of starch.


Assuntos
Géis , Micro-Ondas , Oryza/química , Tamanho da Partícula , Amido/química , Temperatura Alta , Conformação Molecular , Amido/análise , Termodinâmica , Viscosidade
5.
Food Chem ; 306: 125451, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31634767

RESUMO

Gluten-free (GF) breads often lack proteins, minerals and fibres and have an imbalanced energy value, as they are primarily based on flour or starch. To nutritionally fortify GF bread, dietary fibres from milling and fruit processing by-products can be utilized. However, fibre addition changes sensorial, nutritional and also technological properties, such as dough or batter hydration. This review evaluates and compares different methods for quantifying the hydration properties of GF fibres and the resulting batters. Revelations are that the hydration properties of fibres vary greatly, depending on the utilized measuring technique, thus impeding the calculation of the appropriate water amount for GF batter processing. In addition, bran and fibres increase the loss factor tan δ and delay thermal transformation, compromising the specific loaf volume. Finally, operational strategies, such as enzymatic or extrusion treatments are discussed regarding their efficiency to increase water absorption in order to further improve GF bread quality.


Assuntos
Pão/análise , Dieta Livre de Glúten , Fibras na Dieta/análise , Farinha/análise , Frutas/química , Humanos , Amido/análise , Água/química
6.
Food Chem ; 302: 125338, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31434027

RESUMO

This study was designed to evaluate the baking performances of 25 edible dry bean (Phaseolus vulgaris L.) varieties and to investigate correlations among cookie features and rapid test indices (i.e., water and lactic acid retention capacities, oil binding capacity and Rapid Visco Analyzer indices). Two bean powder particle sizes (≤0.5 mm, ≤1.0 mm) were investigated. Cookies were evaluated in terms of nutritional, geometrical and textural properties. Bean powders doubled the amount of cookie protein and increased cookie resistant starch content. Baking potential varied according to bean genotype and powder particle size: coarse powders resulted in larger (+26%) and thinner (-19%) cookies characterized by easier breaking texture (fracture strengths of 41-157 vs. 48-226 kPa for fine powders). Water retention and oil binding capacities and pasting properties significantly (p < 0.05) correlated with cookie features. In conclusion, these accumulated findings can be used in designing value-added traditional and gluten-free cookies.


Assuntos
Phaseolus/química , Pós/química , Culinária , Dieta Livre de Glúten , Farinha , Ácido Láctico/análise , Ácido Láctico/química , Valor Nutritivo , Tamanho da Partícula , Amido/análise , Água/análise , Água/química
7.
Theor Appl Genet ; 132(12): 3357-3374, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31624872

RESUMO

KEY MESSAGE: Seven novel alleles of SBEIIb and one allele of SSIIa co-segregated with the ASV phenotype and contributed to distinct starch quality traits important for food-processing applications. Sorghum is an important food crop for millions of people in Africa and Asia. Whole-genome re-sequencing of sorghum EMS mutants exhibiting an alkali spreading value (ASV) phenotype revealed candidate SNPs in Sobic.004G163700 and Sobic.010G093400. Comparative genomics identified Sobic.010G093400 as a starch synthase IIa and Sobic.004G163700 as a starch branching enzyme IIb. Segregation analyses showed that mutations in Sobic.010G093400 or Sobic.004G163700 co-segregated with the ASV phenotype. Mutants in SSIIa exhibited no change in amylose content but expressed lower final viscosity and lower starch gelatinization temperature (GT) than starches from non-mutant plants. The sbeIIb mutants exhibited significantly higher amylose levels and starch GT and lower viscosity compared to non-mutant starches and ssIIa mutants. Mutations in SBEIIb had a dosage-dependent effect on amylose content. Double mutants of sbeIIb and ssIIa resembled their sbeIIb parent in amylose content, starch thermal properties and viscosity profiles. These variants will provide opportunities to produce sorghum varieties with modified starch end-use qualities important for the beer brewing and baking industries and specialty foods for humans with diabetes.


Assuntos
Amilose/análise , Farinha/análise , Sorghum/genética , Amido/análise , Enzima Ramificadora de 1,4-alfa-Glucana/genética , Álcalis , Alelos , Análise Mutacional de DNA , Dosagem de Genes , Mutação , Fenótipo , Proteínas de Plantas/genética , Polimorfismo de Nucleotídeo Único , Alinhamento de Sequência , Sintase do Amido/genética , Viscosidade
8.
Zhongguo Zhong Yao Za Zhi ; 44(15): 3221-3225, 2019 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-31602875

RESUMO

The non-starch polysaccharides,mainly composed of glucomannans,are the major bioactive compounds in Dendrobium catenatum. In order to evaluate the quality of the medicinal materials and guide the production and processing,a quantification method of non-starch polysaccharides was established by stems of D. catenatum C15 strain collected from the pear epiphytic cultivation. The non-starch polysaccharides were obtained by " water extraction,α-amylase pretreatment,and alcohol precipitation once" method. The contents of starches,non-starch polysaccharides and monosaccharides were analyzed. In addition,the system suitability was tested. Compared with method of the Chinese Pharmacopoeia( 2015 edition),the contents of total polysaccharides,glucose,and mannose were decreased by 20. 9%,58. 8% and 1. 6% respectively. The method effectively digested starch and retained non-starch polysaccharides,and the analysis result was accurate and repeatable. Therefore,it is suitable for the content measurement of non-starch polysaccharides of D. catenatum. Furthermore,it could be an alternative method for quality control of D. catenatum and a reference in the determination of non-starch polysaccharides in other starch-containing medicinal materials.


Assuntos
Dendrobium/química , Polissacarídeos/análise , Monossacarídeos/análise , Compostos Fitoquímicos/análise , Amido/análise
9.
J Dairy Sci ; 102(11): 9857-9869, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31521352

RESUMO

Rehydrated and ensiled mature ground corn has high ruminal starch digestibility, but particle size (PS) and dietary starch proportion (ST) can affect starch digestion and lactating cow performance. We evaluated the effect of rehydrated and ensiled corn (REC), PS, and ST on intake, lactation performance, nutrient digestibility, ruminal fermentation profile, and chewing behavior of dairy cows. Kernels from an 84% vitreousness hybrid were finely (FN) or coarsely (CS) ground, yielding geometric mean particle sizes of 1,591 and 2,185 µm, respectively. Ground kernels were rehydrated [60% dry matter (DM)] and ensiled in 200-L buckets for ≥205 d. The grinding rate (t/h) was 3.9 for FN and 11.7 for CS. The PS did not affect DM loss (11.3% of ensiled) or silage pH (3.8). Samples of each bucket (n = 15/PS) before and after silage fermentation were incubated in situ for 0, 3, 6, 18, and 48 h in 4 rumen-cannulated lactating cows. Ensiling increased the effective ruminal in situ DM degradation (63.7 vs. 34.1%), regardless of PS. Sixteen Holstein cows (152 ± 96 d in milk) in 4 × 4 Latin squares (21-d periods) were individually fed a 2 × 2 factorial combination of low (LO) or high (HI) starch diets with FN or CS. Cows were fed the same REC incubated in situ. Varied concentration of starch in the diet (29.2 vs. 23.5% of DM) was achieved by partial replacement of REC (22.0 vs. 14.2% of DM) with citrus pulp (0 vs. 8.2% of DM). Milk, protein, fat, and lactose yields did not differ. Milk fat percentage was reduced and protein percentage was increased by HI. Treatment FN increased feed efficiency (energy-corrected milk/digestible organic matter intake) when fed with HI. Total-tract starch digestibility tended to be reduced by CS (96.4 vs. 97.2% of starch intake). Serum ß-hydroxybutyrate was increased by LO. High-starch diet reduced the molar proportions of acetate and butyrate in ruminal fluid and increased propionate and isoacids. Particle size did not affect ruminal fermentation profile. Coarse grinding reduced plasma d-lactate concentration with HI. Diet HI reduced the proportion of daily intake from 1900 to 0700 h and induced preferential intake of feed particles <8 mm and greater refusal of particles >19 mm in the morning. Fine REC reduced rumination time per day and increased eating time per DM intake. Milk and plasma urea-N did not differ. Ensiling of mature flint corn for >200 d largely eliminated the effect of the PS of REC on the studied outcomes. The proportion of REC in the diet affected ruminal fermentation profile and milk solids concentration, but did not affect short-term performance and digestibility. Coarse grinding of REC may allow increasing the grinding rate and thus save labor and energy during ensiling.


Assuntos
Bovinos/fisiologia , Leite/química , Tamanho da Partícula , Silagem/análise , Zea mays , Ração Animal/análise , Animais , Dieta/veterinária , Digestão , Grão Comestível , Feminino , Fermentação , Lactação , Lactose/metabolismo , Leite/metabolismo , Distribuição Aleatória , Rúmen/metabolismo , Amido/análise
10.
Food Chem ; 301: 125268, 2019 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-31394333

RESUMO

Morphological, technological and nutritional analyses were done in two scarcely studied starches from Andean tubers (mashua and melloco). The low sedimentation values, and the high zeta potential of mashua and melloco starches in cold dispersions, as consequence of their electronegativity, indicated a better behaviour as stabilizer than potato starch. During heating, mashua and melloco starches presented much higher viscosity than potato starch, associated with their higher average particle size and greater amylose content. DSC and TGA analyses indicated that melloco starch had the highest gelatinization enthalpy ΔHgel (12.32 J g-1) and degradation temperature (270 °C), in comparison with potato starch, which are indicators of a better thermal resistance. Consequently, extracted mashua and melloco starches could be excellent and cost-effective thickening or gelling agents in both foods and a wide range of biomaterials. Mashua and melloco starches exhibited a digestion rate close to 80%, which agreed with the low resistant starch content.


Assuntos
Caryophyllales/química , Farinha/análise , Amido/análise , Tropaeolum/química , Amilose/análise , Equador , Amido/química , Amido/metabolismo , Temperatura Ambiente , Viscosidade
11.
Food Funct ; 10(9): 5436-5445, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31403146

RESUMO

The consumption of ß-glucan-rich barley can contribute to a healthy diet. Sensory properties may be improved by roasting whereby the nutritional value should be preserved. The aim of the present study was to investigate the impact of different roasting conditions (160-200 °C, 20 minutes) on sensory quality, health-related compounds and viscosity in ß-glucan-rich barley kernels, thin and thick flakes. Sensory quality was improved by roasting. Acrylamide levels increased due to roasting to maximum values of 322 µg kg-1 (kernels), 586 µg kg-1 (thin flakes) and 804 µg kg-1 (thick flakes). No relevant impact of roasting on the contents of fat, protein, starch and ß-glucan was observed, whereas dietary fibre fractions were marginally modulated. Roasting significantly decreased viscosity 1.9-fold (kernels), 2.4-fold (thin flakes) and 2.7-fold (thick flakes), on average. In conclusion, improved sensory quality along with a favourable healthy composition of barley products may be achieved by roasting over a low to medium temperature range.


Assuntos
Hordeum/química , Acrilamida/análise , Culinária , Fibras na Dieta/análise , Humanos , Amido/análise , Paladar , Viscosidade , beta-Glucanas/análise
12.
Lett Appl Microbiol ; 69(5): 339-345, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31454416

RESUMO

Khanom-jeen are traditional Thai fermented rice noodles with a characteristic flavour and texture. Based on their ability to hydrolyse rice proteins, five strains of proteolytic bacteria were isolated from fermented rice flour used to produce noodles in Thailand. Enterobacter ludwigii strain SK01 showed the highest degree of rice protein hydrolysis among the five strains and was selected as a starter culture for khanom-jeen production. The viable count of micro-organisms, acidity, pH, and protein and starch contents were compared throughout the fermented rice production with and without the SK01 strain. The pH of fermented rice increased on the first day of solid-state fermentation and subsequently decreased to 3·7-3·8 under both conditions. The protein content of rice significantly decreased from 80 to 18·2 ± 0·5 mg g-1 and 26 ± 0·6 mg g-1 during fermentation with and without the SK01 strain, respectively. The tensile strength, breaking length, brightness, and whiteness, which are important factors for the texture and appearance of khanom-jeen, were improved using the SK01 strain to ferment rice. The results of this laboratory-scale study indicated that the use of the proteolytic SK01 strain in fermented rice production can improve the quality of khanom-jeen noodles. SIGNIFICANCE AND IMPACT OF THE STUDY: The use of Enterobacter ludwigii strain SK01 as a proteolytic bacterial starter culture improved the quality of khanom-jeen noodles. Compared with khanom-jeen noodles produced without E. ludwigii strain SK01, those produced using this strain showed increased tensile strength, breaking length, brightness and whiteness. These findings will be useful for the development of specific and controllable methods for producing khanom-jeen noodles with desirable texture and colour.


Assuntos
Bactérias/metabolismo , Oryza/microbiologia , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Cor , Enterobacter/genética , Enterobacter/isolamento & purificação , Enterobacter/metabolismo , Fermentação , Farinha/análise , Farinha/microbiologia , Oryza/química , Amido/análise , Amido/metabolismo , Tailândia
13.
Forensic Sci Int ; 302: 109861, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31265983

RESUMO

Today, rape and sexual assault cases are mainly solved using evidence such as medical evidence or DNA analysis. Condom traces have been found to be present in 10% of assaulted women, when no DNA is found [1]. Numerous studies have emphasized the interest of analysing the composition of male condoms and their traces, and developing specific methods for the analysis of this type of evidence. However, transfer and persistence of condom traces in a specific matrix are rarely referenced. Therefore, forensic scientists have no complete knowledge of the trace and what could be expected in a real case. The purpose of this article is to review the literature addressing the composition of condoms and their traces as well as its influence on the transfer and persistence from a forensic point of view. Peer-reviewed literature, patents, professional literature, data from international administrations and international organisations' reports have been used to track the composition and the problematics of transfer and persistence of condom traces. The results of this review show that the composition of male condoms and their traces are complex systems, with numerous compounds originating from the condom at the moment of the transfer and evolving over time according to specific persistence patterns. Although numerous types of analyses have already been proposed and tested for condom traces, forensic evidence considerations have not been fully studied yet. Considering the fact that sexual assaults without the detection of DNA are increasingly frequent, there is a definite medical and forensic need to improve our knowledge of the processes involved in the development of condom traces in order to better understand analytical results.


Assuntos
Preservativos , Delitos Sexuais , Vagina/química , Anestésicos Locais/análise , Antioxidantes/análise , Dimetilpolisiloxanos/análise , Feminino , Aromatizantes/análise , Medicina Legal , Humanos , Látex/análise , Lubrificantes/análise , Masculino , Nitrosaminas/análise , Odorantes/análise , Polietileno/análise , Polietilenoglicóis/análise , Pós , Conservantes Farmacêuticos/análise , Espermicidas/análise , Amido/análise
14.
Food Chem ; 298: 124982, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31261014

RESUMO

This work studies the physicochemical properties of quinoa flour and isolated starch. Starch in the seed forms clusters rich in amylopectin that are immersed in a matrix with spherical and polygonal shapes in the submicron scale. The isolated quinoa starch is rich in Sulphur and Magnesium. The quinoa flour has a higher content of protein, carbohydrates and lipids than isolated starch. Water absorption and water solubilized indexes of starch exhibited high values that could had originated by the extraction method. The broad peaks found for the X-ray patterns of isolated quinoa starch indicate that amylose and amylopectin are composed by nanocrystals, according to the PDF-4+2019 software. The viscosity of isolated starch had a higher value than flour; therefore, the quinoa starch could be used as a thickener in different formulations with the advantage of keeping a significant presence of minerals which are important to the human health.


Assuntos
Chenopodium quinoa/química , Farinha/análise , Análise de Alimentos/métodos , Amido/química , Amilopectina/química , Amilose/análise , Microscopia Eletrônica de Varredura , Minerais/análise , Sementes/química , Sementes/ultraestrutura , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier , Amido/análise , Amido/ultraestrutura , Temperatura Ambiente , Viscosidade , Água/química , Difração de Raios X
15.
J Dairy Sci ; 102(9): 7970-7979, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31301837

RESUMO

This study was designed to evaluate the effects of substituting corn grain with nonforage fiber sources in diets containing soybean meal (SBM) or canola meal (CM) as the primary protein source. Sixteen Holstein cows were assigned to a replicated 4 × 4 Latin square design with 4 periods of 28 d each. Treatments were arranged as a 2 × 2 factorial with 2 protein sources (SBM and CM) and 2 dietary starch concentrations (21 and 27% dry matter, DM). Diets were formulated to contain 16.5% CP, and the 21% starch diets were obtained by replacing corn grain with soybean hulls and beet pulp. Protein source × starch interactions were observed for DM intake (DMI), milk fat and protein concentrations, milk protein yield, milk urea nitrogen, and feed efficiency. Cows fed CM diets had a higher DMI when dietary starch concentration was 27% compared with 21%, but those cows had DMI similar to that of cows on SBM diets regardless of the starch concentration. Milk fat percentage was decreased in cows fed CM with 27% starch compared with cows fed CM with 21% starch and cows fed SBM with 27% starch. Milk protein percentage and yield and milk lactose percentage were least in cows fed CM with 21% starch compared with the other 3 diets, but feed efficiency was greater for cows fed CM with 21% starch. Milk urea nitrogen was least in cows fed CM with 27% starch compared with the other 3 diets. Cows fed diets with 27% starch produced 2.5 kg/d more milk and 1.9 kg/d more energy-corrected milk compared with cows fed 21% starch. Digestibility of DM and organic matter was higher in cows fed SBM diets than in cows on CM diets, and cows fed 27% starch showed greater DM and organic matter digestibility than cows on 21% starch. Digestibility of neutral detergent fiber and acid detergent fiber was greater in diets with SBM than in those with CM. Molar proportion of acetate was the lowest for cows fed CM with 21% starch compared with cows fed SBM with 21% starch, with the remaining cows fed being intermediate and similar. However, propionate was highest for cows fed CM with 21% starch than for cows fed SBM with 21% starch, but the remaining treatments were intermediate and similar. Isobutyrate was greater for cows fed CM with 21% starch, which resulted in the lowest acetate:propionate ratio compared with cows fed the remaining treatments. Overall, we confirmed that the interaction of protein with starch in CM diets can sustain similar cow performance as with the SBM diets. Those making decisions about starch concentration and protein source should consider feed price when SBM or CM and different starch levels are being formulated in diets for lactating dairy cows.


Assuntos
Ração Animal , Brassica napus , Bovinos/fisiologia , Proteínas na Dieta/administração & dosagem , Soja , Amido , Ração Animal/análise , Animais , Indústria de Laticínios , Dieta/veterinária , Fibras na Dieta , Feminino , Lactação , Lactose/metabolismo , Leite , Proteínas do Leite , Distribuição Aleatória , Silagem/análise , Amido/análise , Zea mays/metabolismo
16.
Food Chem ; 299: 125095, 2019 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-31279124

RESUMO

Hydrogen gas (H2), a multifunctional signaling molecule, has received increasing attention in recent years. In the present study, hydrogen-rich water (HRW) (2 ppm) was used for the processing of sprouted black barley (Hordeum distichum L.), and the results showed that the HRW treatment could significantly increase the germination rate and growth rate of black barley (P < 0.05). A chemical component analysis showed that in sprouted black barley, the HRW treatment could change the distribution of phytochemicals (e.g., the ionic strength of guanosine), increase the concentrations of free vanillic acid, coumaric acid, sinapic acid, conjugated sinapic acid, Ca and Fe and the hydroxyl radical scavenging rate, and decrease the protein, fat, starch and dietary fibre contents compared with the results obtained after treatment with ultra-pure water (P < 0.05). HRW can be used for the processing of sprouted grains to effectively increase their germination efficiency and concentrations of bioactive phytochemicals.


Assuntos
Hordeum/química , Hordeum/crescimento & desenvolvimento , Hidrogênio/farmacologia , Antioxidantes/análise , Cromatografia Líquida , Fibras na Dieta/análise , Germinação/efeitos dos fármacos , Hordeum/efeitos dos fármacos , Radical Hidroxila/análise , Espectrometria de Massas , Proteínas de Vegetais Comestíveis/análise , Amido/análise , Água/química , Água/farmacologia
17.
Food Chem ; 300: 125192, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31362158

RESUMO

Dietary fiber has several benefits for humans, and the development of healthier rice with an improved dietary fiber composition has attracted increasing amounts of attention. Based on the method of AOAC 2002.02, we developed a simplified method to screen polished rice containing high total dietary fiber (TDF). Mutant cw with a high TDF content could be distinguished easily from R7954 (indica) and Nipponbare (japonica) by the digestion-resistant phenotype, which is characterized as an almost intact grain after hydrolysis by pepsin, pancreatic α-amylase and amyloglucosidase. The individuals identified from the F2 population showed digestion resistance all had TDF content higher than 5%, while those without a digestion-resistant phenotype had TDF content lower than 5%. The phenotype of digestion resistance could be a valuable index for identifying rice with higher TDF content, and the identification of this phenotype provides a simplified, economical and high throughput method for high TDF rice breeding.


Assuntos
Fibras na Dieta/análise , Análise de Alimentos/métodos , Ensaios de Triagem em Larga Escala/métodos , Oryza/química , Culinária , Fibras na Dieta/metabolismo , Digestão , Glucana 1,4-alfa-Glucosidase/química , Glucana 1,4-alfa-Glucosidase/metabolismo , Humanos , Hidrólise , Pepsina A/química , Pepsina A/metabolismo , Sementes/química , Amido/análise , Amido/química , alfa-Amilases/química , alfa-Amilases/metabolismo
18.
J Food Sci ; 84(7): 1730-1736, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31218701

RESUMO

With high phytochemical and starch contents, purple-fleshed sweetpotatoes (PFSP) have been processed into various functional ingredients and food products including juices and natural colorants. For juice processing, PFSP are usually subjected to heat treatment for inactivation of pigment-degrading enzymes. However, heating of sweetpotatoes gelatinizes starch and produces thick slurry with cooked flavor, which are the drawbacks. Development of alternative processes to overcome the stated problems will be beneficial to sweetpotato processors. This study demonstrated that acidified water (≥3% w/v citric acid) was effective in inhibiting polyphenol oxidase and peroxidase in raw PFSP resulting in an attractive reddish juice. About 93% total phenolics (TP) and 83% total monomeric anthocyanins (TMA) in PFSP were extracted by two repeated extractions. The combined PFSP juice (3.2 L/kg PFSP) had high levels of TP (1,850 mg/L) and TMA (475 mg/L). With the developed process, 167 g dried starch, and 140 g dried high-fiber pomace were obtained for each kg raw PFSP, besides the highly pigmented juice. Pasteurization of the PFSP juice samples (pH 3.2) at 80 °C for 12 s resulted in 15% loss in TMA and had no effect on TP. The results indicated an efficient process to produce sweetpotato juice with high bioactive compounds and recovery of starch and high dietary fiber pomace as co-products. PRACTICAL APPLICATION: Purple-fleshed sweetpotatoes (PFSP) are rich in polyphenolics and antioxidant activities. In PFSP juice extraction, heat treatment to inactivate the pigment-degrading enzymes results in starch gelatinization and cooked flavor. A nonthermal process using acidified water was developed for producing anthocyanin-rich juice from PFSP and concurrently recovering native starch and dried pomace, which would increase the economic feasibility of the developed process. The results demonstrate an efficient process for the sweetpotato industry in producing PFSP pigmented juice and co-products for various food applications.


Assuntos
Ácidos/química , Antocianinas/análise , Catecol Oxidase/antagonistas & inibidores , Sucos de Frutas e Vegetais/análise , Ipomoea batatas/química , Peroxidase/antagonistas & inibidores , Extratos Vegetais/análise , Proteínas de Plantas/antagonistas & inibidores , Antocianinas/isolamento & purificação , Catecol Oxidase/análise , Cor , Culinária , Fibras na Dieta/análise , Ipomoea batatas/enzimologia , Peroxidase/análise , Fenóis/análise , Fenóis/isolamento & purificação , Extratos Vegetais/isolamento & purificação , Proteínas de Plantas/análise , Amido/análise
19.
Food Chem ; 297: 124879, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31253268

RESUMO

This study determined the effects of phenolic extracts from grape pomace and sorghum bran, reaction time and washing with aqueous ethanol on the pasting, flow, thermal and molecular properties of maize starch. The starch modification was carried out under alkaline conditions. The phenolic extracts increased the peak viscosity of the starch. Reaction time had no significant effect on starch properties. Washing with aqueous ethanol significantly increased the peak, final, and setback viscosities of the phenolic modified maize starches. DSC of phenolic modified starches showed higher enthalpy (ΔH) before and after washing with aqueous ethanol in comparison with starch without phenolic extract. FTIR spectra suggested the possible formation of hydrogen and ether (covalent) bonds between starch and phenolic compounds. It can be concluded that the pasting, flow and thermal properties of maize starch can be modified with phenolic extract under alkaline conditions to produce "clean label" starch-phenolic complex.


Assuntos
Fenóis/química , Extratos Vegetais/química , Sorghum/química , Amido/química , Vitis/química , Zea mays/metabolismo , Liofilização , Concentração de Íons de Hidrogênio , Sorghum/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier , Amido/análise , Temperatura Ambiente , Termodinâmica , Viscosidade , Vitis/metabolismo
20.
Plant Foods Hum Nutr ; 74(3): 342-349, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31177359

RESUMO

Dry beans (Phaseolus vulgaris L.) are a nutrient dense food rich in protein, dietary fiber, minerals, and folate. Consumption of dry beans is relatively low in the United States and this may be due in part to the lack of diversity in bean products beyond whole seeds. Products that incorporate beans in new forms, such as flours, offer the potential to increase dry bean utilization. In this study whole dry beans were milled into flour and used to make gluten free fresh pastas. Six bean varieties each from a different market class (white kidney, navy, otebo, cranberry, dark red kidney and black) were made into pasta. Their consumer appeal was compared to fresh wheat pasta and their nutritional value was compared to fresh wheat pasta and whole boiled beans. The dry bean pastas were nutritionally superior to wheat pasta with higher protein, ash, resistant starch and protein digestibility corrected amino acid score (PDCAAS) as well as lower total starch content. While consumers preferred the flavor, texture and appearance of the wheat pasta to the dry bean pasta, 36% of participants said they would definitely or probably purchase the dry bean pastas from the light colored beans. There was some loss of nutritional value of bean pasta vs. whole boiled beans but this can mostly be attributed to the bean pasta being 90% bean. These results suggest that single variety fresh dry bean pastas have commercial potential in the U.S. as healthy gluten free pasta options.


Assuntos
Comportamento do Consumidor , Fibras na Dieta/análise , Farinha/análise , Valor Nutritivo , Phaseolus/química , Humanos , Sementes/química , Amido/análise , Paladar , Triticum/química
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