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1.
Food Chem ; 341(Pt 2): 128203, 2021 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-33038803

RESUMO

Two different pearling degrees of wheat kernels (lightly-pearled: 14.4% and heavily-pearled: 38.9%) and un-pearled kernels were treated with ozone and evaluated for flour compositions and properties. Ozonation did not change main compositions and damaged starch content of three kernels' flours. Flour brightness of all three kernels was improved after ozone treatment. Ozonation enhanced the dough strength of the flours from un-pearled and pearled kernels and the effect elevated with increasing pearling degree. Ozone treatment increased the peak viscosity of flour and the level of increase in heavily-pearled kernels was greater than un-pearled and lightly-pearled. Ozonation resulted in an increase in the insoluble protein polymer content of heavily-pearled kernels' flour, but only had a slight effect on un-pearled lightly-pearled kernels. After ozone treatment, un-pearled and lightly-pearled kernels exhibited increases in molecular weight of starch, but heavily-pearled resulted in the opposite trend.


Assuntos
Farinha/análise , Ozônio/química , Triticum/metabolismo , Glutens/análise , Peso Molecular , Amido/análise , Viscosidade
2.
Food Chem ; 338: 127803, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-32822899

RESUMO

Quercus acorns have been used as a staple food since archeological times; currently, there is a renewed interest in the direct use of the acorns as nuts or as a source of consumable flour. In this regard, the phytochemical composition and variability of various morphotypes of acorns from Quercus ilex have been determined by using two platforms, near infrared spectroscopy (NIRS) and mass spectrometry (MS)-based metabolomics. According to NIRS, starch was the most abundant compound (50-60%). UHPLC-QToF analysis was used for untargeted metabolomic analysis and 192 metabolites were annotated. Principal component analysis (PCA) discriminated the morphotypes; 50 compounds out of 192 identified had the highest load over the first two PCA components (explaining 67.2% variability) and can be potential markers of variability. The data presented here support the value of acorns as a source of nutritionally rich compounds thus justifying their use a good alternative to other nuts.


Assuntos
Compostos Fitoquímicos/análise , Quercus/química , Sementes/química , Sementes/fisiologia , Cromatografia Líquida de Alta Pressão , Análise de Componente Principal , Quercus/metabolismo , Sementes/anatomia & histologia , Espectroscopia de Luz Próxima ao Infravermelho , Amido/análise , Espectrometria de Massas em Tandem
3.
Food Chem ; 339: 127917, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-32950898

RESUMO

Andean beans (Phaseolus vulgaris) chemical compositions and cooking characteristics contribute to a healthy diet. The objective of this study was to evaluate the influence of chemical composition on the cooking quality of 14 Andean beans genotypes with different seed coat colors. More specifically, water retention (WR), cooking time (CT), and solids released in the broth, were analysed. WR values ranged from 128.4% to 160.7% and CT ranged from 13.7 (BRS Embaixador) to 21.7 min (KID44). Andean beans showed variability in chemical composition, mainly starch content (39.43 g 100 g-1, BRS Realce to 51.92 g 100 g-1, LP15-04) and polymer composition. The profile of starch and interactions among minerals and chemical compounds influenced the cooking profiles than do the individual compounds. Andean beans traits of cooking, mainly CT, were influenced by their chemical composition; however they can be incorporated into diets without drastic changes in preparation methods.


Assuntos
Culinária/métodos , Phaseolus/química , Amido/análise , Amilopectina/análise , Amilose/análise , Genótipo , Minerais/análise , Análise Multivariada , Phaseolus/genética , Phaseolus/metabolismo , Sementes/química , Sementes/genética , Sementes/metabolismo
4.
Food Chem ; 335: 127505, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-32739823

RESUMO

Dysregulation of glucose homeostasis result in hyperglycemia and pigmented rice, unique combination of high quality starch and phenolics has the potential in regulating it. In this study, pigmented rice was characterized in terms of nutraceutical starch (NS) and phenolic content. Further the effect of rice phenolics on carbolytic enzyme inhibition, glucose uptake, hepatic glucose homeostasis and anti-glycation ability was analyzed in vitro. The most relevant effect on enzyme inhibition (α-amylase: IC50-42.34 µg/mL; α-glucosidase: IC50:63.89 µg/mL), basal uptake of glucose (>39.5%) and anti-glycation ability (92%) was found in red rice (RR), than black rice (BR). The role of RR phenolics in regulating glucose homeostasis was deciphered using hepatic cell line system, which found up-regulation of glucose transporter 2 (GLUT2) and glycogen synthase 2 (GYS2); while expression of gluconeogenic genes were found down regulated. To our knowledge this study is the first report validating the role of starch-phenolic quality towards anti-hyperglycemic effect of RR.


Assuntos
Glucose/metabolismo , Homeostase , Hiperglicemia/metabolismo , Fígado/metabolismo , Oryza/química , Proantocianidinas/análise , Amido/análise , Transporte Biológico/efeitos dos fármacos , Suplementos Nutricionais/análise , Inibidores de Glicosídeo Hidrolases/farmacologia , Homeostase/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fenol/análise , Fenol/farmacologia , alfa-Amilases/antagonistas & inibidores
5.
Food Chem ; 336: 127668, 2021 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-32758805

RESUMO

Hulled Reins and hulless Lamont oats were dehulled and/or sequentially abraded to produce ten pearling fines and corresponding pearled kernels. Contents of nutrients (protein, oil, starch, beta-glucan, ash and other carbohydrates) and avenanthramides (AVA) 2p, 2c, 2f, and 5p in processing fractions and starting grains were measured. Results show that distribution patterns of nutrients varied with individual nutrients, but those of AVAs varied with variety and individual AVAs. In both varieties, from the surface to inner endosperms, protein and oil increased then decreased; ash and other carbohydrates decreased; starch increased; and beta-glucan unchanged except for the surface area. In Lamont oat, the four AVAs decreased, but in Reins oat, AVA 2p decreased while 2c, 2f and 5p increased, then decreased. Compared to whole grain, pearled oats not only contained lower AVAs, protein, oil, ash, and other carbohydrates and higher beta-glucan and starch but also had a different AVA composition.


Assuntos
Avena/química , Sementes/química , ortoaminobenzoatos/análise , Nutrientes/análise , Proteínas de Vegetais Comestíveis/análise , Amido/análise , beta-Glucanas/análise
6.
Food Chem ; 340: 127908, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-32889206

RESUMO

This study aims to evaluate the effects of in vitro digestion of rice and common bean blends on phenolics content and profile. Black and carioca beans were used as common bean sources. Blends consisted of 25:75, 50:50, and 75:25 polished rice:beans (w/w). Pure rice or pure beans were also analyzed. Phenolic compounds were determined in raw, cooked, and digested samples. The glucose release through in vitro digestion was slower as the proportion of black beans or carioca beans increased. Starch digestibility ranged between 41.1 in 100% carioca bean to 84.4% in 100% rice. Hydroxybenzoic acid, ferulic acid, p-coumaric acid, catechin, and epicatechin were the most abundant phenolics detected in the studied samples. Considering the content of phenolic compounds determined in the raw, cooked, and digested grains, only a small fraction was available for absorption in the gut, with amounts varying from 0.1 to 0.6 µg·g-1.


Assuntos
Oryza/química , Phaseolus/química , Fenóis/análise , Amido/química , Amido/farmacocinética , Catequina/análise , Catequina/química , Culinária , Digestão , Glucose/farmacocinética , Hidroxibenzoatos/análise , Hidroxibenzoatos/química , Fenóis/química , Amido/análise
7.
J Dairy Sci ; 103(11): 10122-10135, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32896410

RESUMO

Leftover bakery by-products (BP) from bakeries and supermarkets may serve as energy-rich ingredient in ruminant diets. The aim of the present study was to evaluate the effect of the successive substitution of cereal grains by BP on dry matter (DM) intake, milk production, and metabolic health as well as ruminal pH and eating and chewing behavior of dairy cows. Twenty-four lactating Simmental cows (149 ± 22.3 d in milk, lactation number 2.63 ± 1.38, 756 ± 89.6 kg of initial body weight) were fed a total mixed ration containing a 50:50 ratio of forage to concentrate throughout the experiment (35 d). During the first week, all cows received a control diet (without BP) as a baseline (d -7 to 0). In the next 4 wk (d 1 to 28), cows were allocated to 3 groups differing in the BP concentrations of diets [0% BP (CON), 15% BP, and 30% BP on a DM basis]. The DM intake and reticuloruminal pH were continuously measured. Blood and milk samples were taken every week, but only results from the experimental period (d 21 and 28) were used for statistical analyses, whereas results from the baseline were considered covariates. Diet analyses showed that BP inclusion increased the ether extract and sugar contents, whereby starch and neutral detergent fiber decreased. Experimental data showed that feeding BP in the diet increased DM intake. Furthermore, the cows fed 30% BP produced roughly 4 kg/d more milk and energy-corrected milk than the CON cows. The milk urea nitrogen was lower in cows fed the BP. Feeding BP reduced the blood glucose and insulin concentrations, whereas nonesterified fatty acids, ß-hydroxybutyrate, and cholesterol increased linearly. Cows fed 15% BP had the shortest period of time in which ruminal pH was below 5.8, in contrast to CON cows (+188 min/d). Taken together, the results suggest that the inclusion of up to 30% BP in the diets of mid-lactation dairy cows shifted the nutrient profile from a glucogenic diet to a lipogenic diet, holding the potential to enhance performance and lower the risk of subacute ruminal acidosis in dairy cows.


Assuntos
Acidose/veterinária , Ração Animal/análise , Doenças dos Bovinos/prevenção & controle , Bovinos/fisiologia , Metaboloma , Leite/metabolismo , Acidose/prevenção & controle , Animais , Análise Química do Sangue/veterinária , Peso Corporal , Bovinos/sangue , Dieta/veterinária , Fibras na Dieta/análise , Ingestão de Alimentos , Grão Comestível , Feminino , Concentração de Íons de Hidrogênio , Lactação , Estudos Longitudinais , Mastigação , Leite/química , Rúmen/metabolismo , Amido/análise , Resíduos/análise
8.
J Food Sci ; 85(11): 3722-3730, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32990365

RESUMO

The present study aims to produce arrowroot flour fermented by kefir grains, in addition to assessing the physicochemical, nutritional, and microbiological characteristics. Fermented arrowroot flour was produced at room temperature (approximately 25 to 28 °C). Fermentation was conducted in batch (6 kg of the substrate and 10% of kefir grains were added with homogenization every 3 hr). Samples were evaluated every 12 hr for both fermentation processes (fermentation process 1: 24 hr and fermentation process 2: 48 hr). The flours were evaluated for physicochemical, nutritional, and microbiological qualities, using a completely randomized design, considering only the variation in the duration of both fermentation processes (from 24 to 48 hr). The fermentation process positively modified the physicochemical, nutritional, and microbial characteristics of the flours. An increase in antioxidant activity (IC50 : control flour [CF] = 18.9 ± 0.13; arrowroot kefir flour [24 hr of fermentation; AKF1] = 15.36 ± 0.14; and arrowroot kefir flour [48 hr of fermentation; AKF2] = 13.84 ± 0.15), protein percentage (CF = 3.08 ± 0.12; AKF1 = 4.87 ± 0.33; and AKF2 = 6.00 ± 0.07), and organic acid (lactic, acetic, and propionic acids) production was observed, as well as modification in color (browning), the conformation of starch structures, and carbohydrate reduction. These results suggested that the "arrowroot kefir flours" open a new perspective for introduction in the market as a new product that can be used as food in nature or food ingredient for making bread, biscuits, pasta, and others, showing microbiological safety and functions properties. PRACTICAL APPLICATION: The fermented flours present improved nutritional characteristics due to the fermentation process, such as higher antioxidant activity and protein levels. Regarding the population growth and societal demand for healthier food, one possibility is to provide a fermented flour with added nutritional value and raise knowledge about the arrowroot. Thus, these flours can be used in various food items or as an ingredient in food preparations for consumers that desire a healthy diet.


Assuntos
Farinha/análise , Kefir/análise , Marantaceae/química , Pão/análise , Fermentação , Indústria Alimentícia , Valor Nutritivo , Amido/análise
9.
J Food Sci ; 85(10): 3141-3149, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32857867

RESUMO

Hull-less barley (HLB), especially waxy HLB, contains many physiologically active ingredients; however, its poor processing performance and end-product quality are unfavorable. In this study, 80% waxy or normal HLB wholegrain flour (WGF) and 20% wheat flour were used for baking bread. The farinograph and pasting properties of composite powders, and the nutritional value, textural properties, and in vitro hydrolysis of resultant breads were evaluated. The addition of a high proportion of HLB WGFs significantly increased the nutritional value of breads, especially the ß-glucan contents of waxy HLB breads. The addition of HLB WGFs and a suitable amount of wheat gluten led to a lower degree of softening of HLB bread flours but improved its farinograph characteristics, such as higher water absorption rate, development time, stability time, and farinograph quality number. Although the sensory profiles of HLB breads were considerably lower than those of wheat bread, they still received a good overall acceptability from a panel of sensory evaluators. HLB breads, particularly the waxy types, exhibited higher hardness, gumminess, chewiness, and lower specific volume, glycemic index and equilibrium concentration in starch hydrolysis. After baking, the starch crystallinity of dough changed from A to V type, and the relative crystallinity decreased. Overall, waxy HLB breads had more nutritional value than normal HLB breads. Higher ß-glucan and total dietary fiber content in HLB might have a positive effect on the nutritional value of the resultant breads. However, high ß-glucan and total dietary fiber was also accompanied by a negative effect on the sensory quality and processing performance of the end product. PRACTICAL APPLICATION: The composite flour with 80 g hull-less barley wholegrain flour, 20 g wheat flour, and 30 g wheat gluten can be substituted in breadmaking. Compared to wheat bread, hull-less barley bread exhibited different but acceptable sensory properties and had more nutritional value, particularly the waxy one. Therefore, a high proportion of hull-less barley could be recommended for bread production.


Assuntos
Pão/análise , Farinha/análise , Manipulação de Alimentos/métodos , Hordeum/química , Amido/análise , Fibras na Dieta/análise , Digestão , Aditivos Alimentares/análise , Manipulação de Alimentos/instrumentação , Glutens/análise , Índice Glicêmico , Dureza , Humanos , Valor Nutritivo , Triticum/química
10.
J Dairy Sci ; 103(10): 8910-8921, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32713693

RESUMO

This study evaluated the effects of conditioner retention time during the pelleting process of starter feed on intake, nutrient digestibility, ruminal fermentation, blood metabolites, and growth performance of dairy calves. A total of 30 Holstein female dairy calves [40 ± 1.93 kg of body weight (BW)] were randomly assigned to 1 of 3 treatments: (1) pelleted starter conditioned for 0 min (CON), (2) pelleted starter conditioned for 2 min, and (3) pelleted starter conditioned for 4 min. Three pelleted starter feeds had similar nutritional composition, and the starters were blended with 3% chopped wheat straw and fed to individually housed calves from d 3 to 70 of age. All calves were fed 4 L/d of pasteurized whole milk twice daily at 0800 and 1600 h from d 3 to 50 of calf age, followed by 2 L/d of morning feeding from 51 to 56 d of age. All calves were weaned on d 56 of age and remained in the study until d 70 of age. With the increase of conditioner retention time during pellet processing for 0, 2, and 4 min, the gelatinized starch content of pelleted starter feed linearly increased from 14, 30, and 45%, respectively. Additionally, the pellet durability and hardness also linearly increased with increasing conditioner retention time during pelleting. Feeding pelleted feed prepared using different conditioner retention time did not affect feed dry matter intake, metabolizable energy intake, weaning BW, final BW, or feed efficiency during the study. We observed no differences in the total-tract apparent digestibility of organic matter, neutral detergent fiber, and crude protein around weaning (d 49 to 56 of age) and after weaning (d 63 to 70 of calf cage); however, the digestibility of dry matter and starch after weaning was increased with increasing conditioner retention time during pelleting of starter feed. No difference was found in overall average daily gain (ADG) or growth rates of hip height, withers height, and heart girth. Ruminal volatile fatty acid profile was not affected by pelleting under different conditioner retention times. The ruminal ammonia concentration tended to be lower for calves fed the 4-min diet compared with those fed the CON diet during the postweaning period. The postweaning (d 57-70 of age) ADG was greater for calves fed the 4-min diet compared with those fed the CON diet. In conclusion, the conditioning time during the pelleting process of starter feed increased the gelatinization of starch, durability, and hardness of the pellets but did not influence feed intake, feed efficiency, and skeletal growth during the first 70 d of age. Increasing conditioning time during the pelleting process improved postweaning ADG; however, the final BW of calves was similar among treatments.


Assuntos
Ração Animal , Bovinos/crescimento & desenvolvimento , Digestão/fisiologia , Fermentação/fisiologia , Manipulação de Alimentos/métodos , Rúmen/fisiologia , Ração Animal/análise , Animais , Peso Corporal , Bovinos/metabolismo , Dieta/veterinária , Fibras na Dieta/metabolismo , Ácidos Graxos Voláteis/metabolismo , Feminino , Masculino , Nutrientes/metabolismo , Amido/análise , Amido/metabolismo , Desmame
11.
J Plant Physiol ; 251: 153206, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32512382

RESUMO

A broad diversity of phenotypes are available within the cassava germplasm collections. The phenotypes include improved nutritional, starch or culinary root quality as well as abiotic and biotic resistance properties. Some of these traits can be found naturally occurring in cassava landraces, whereas others are the result of targeted breeding efforts. For future breeding programmes it is important to know the underlying mechanisms of these desirable traits. Metabolomics can assist in the elucidation of these mechanisms by measuring the end products of the cellular processes conferring the traits of interest. The present study focused on the comparison of two or more variants of the same trait such as high and low culinary quality or resistance and susceptibility to thrips. Overall, eight different traits were assessed. Results showed that amino acids and umami compounds were associated with superior culinary attributes and the phenylpropanoid superpathway plays an important role in pest resistance. Furthermore, the data highlighted a low chemodiversity in African cassavas and that the source-sink relation was still active at the harvest stage.


Assuntos
Aminoácidos/análise , Manihot/química , Redes e Vias Metabólicas , Monossacarídeos/análise , Amido/análise , Qualidade dos Alimentos , Manihot/metabolismo , Fenótipo , Melhoramento Vegetal
12.
J Food Sci ; 85(6): 1725-1734, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32484938

RESUMO

The proximate composition, total phenolics, antioxidant activity, minerals, and trace elements were determined in 42 barley landraces in order to highlight their nutritional potential and promote their cultivation. Two-row barley landraces had a higher average content of starch, protein, total phenolic compounds, and iron, when compared with six-row ones that presented higher mean ash and fiber concentrations. Additionally, the six-row barley landraces with strongly pigmented grains had lower zinc and manganese and higher protein mean concentrations than the whitish or lightly pigmented barley landraces. Factor analysis and linear discriminant analysis were used to correctly differentiate samples according to type of barley (landrace or commercial) and number of rows. In general, all the parameters varied considerably among the barley landraces analyzed, but some barley landraces could be emphasized according to fiber, minerals, and phenolic antioxidants. There were important differences in the mean values in all the chemical parameters according to the island of origin of the barley grains. The application of linear discriminant analysis was also a useful tool to differentiate all the barley landraces with six rows according to the island of origin. PRACTICAL APPLICATION: Barley is a versatile cereal that can be used for human and animal feed, brewing, and as biodiesel. From the nutritional point of view, barley is rich in starch, protein, dietary fiber and minerals, as well as antioxidant compounds and vitamins. The landraces analyzed in this study have remained intact for the last 900 years, which gives opportunity to genome of these barley landraces to evolve some very specific traits. The physicochemical characterization of these local landraces carried out by us could be very useful as a source of new quality in breeding programs.


Assuntos
Hordeum/química , Minerais/análise , Sementes/química , Cruzamento , Fibras na Dieta/análise , Hordeum/classificação , Hordeum/genética , Proteínas de Plantas/análise , Espanha , Amido/análise
13.
J Sci Food Agric ; 100(12): 4409-4417, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32388854

RESUMO

BACKGROUND: Lines of the internationally recognized old Hungarian Bánkúti 1201 variety are important genetic resources for breeding programmes. Their protein composition and gluten dependent technological traits have been comprehensively studied, however, little information is available about their carbohydrate dependent viscous properties. The aim of this work was to obtain comprehensive rheological characterization of all sublines of Bánkúti 1201 maintained at Martonvásár and to investigate their variability if the carbohydrate dependent viscous behaviour was also included in the analyses. RESULTS: The majority of the lines reflected the famously good mixing quality of Bánkúti, however, much higher diversity of pasting behaviour was detected. Cluster analysis of the Mixolab data was performed resulting in four sample groups. Since several lines of similar mixing properties had significantly different pasting characteristics, it was assumed that classification was mainly based on the viscous properties. From each cluster two to three representative samples were selected for wider examination using conventional testing methods. These results also supported the higher variability of pasting behaviour of the lines, which can be critical for end product quality. The members of the second cluster can be highlighted due to their waxy wheat like behaviour. CONCLUSIONS: Possible reasons for the great variability of pasting behaviour could be the compositional and structural differences of starch and other carbohydrates (e.g. arabinoxylans). Complex rheological characterization and study of molecular background can provide information about important traits from the point of view of technology and product development, which are unknown in the case of old wheat varieties and landraces. © 2020 Society of Chemical Industry.


Assuntos
Reologia/métodos , Triticum/química , Glutens/análise , Sementes/química , Amido/análise , Triticum/classificação , Triticum/genética , Viscosidade
14.
Chemosphere ; 256: 127107, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32445992

RESUMO

The massive use of petroleum-based polymers and their improper waste treatment has brought on significant global environmental problems due to their non-biodegradable nature. Starch/poly(vinyl alcohol) (PVA) bioplastics are suitable substitutes for conventional polymers, such as polyethylene, due to their full biodegradability and excellent mechanical properties. Knowledge of the pollutant emissions during pyrolysis and combustion of starch/PVA films is important because they can arrive at landfills mixed with conventional polymers and be thermally degraded in uncontrolled fires. On the other hand, controlled thermal treatments could result in thermal valorization of the waste. Pyrolysis and combustion experiments were carried out at 650, 750, 850 and 950 °C in a laboratory furnace. The analysis of carbon oxides, light hydrocarbons, and semivolatile compounds, including polycyclic aromatic hydrocarbons (PAHs), is shown. Experiments showed lower pollutant emissions than those found with conventional polymers, such as polyethylene and polyester, in the same equipment. Nevertheless, the pyrolysis run at 950 °C showed the highest light hydrocarbon yield (123013 mg kg-1), but this is considerably lower than the values found for polyethylene. The main semivolatile compounds (not PAHs) emitted, with maximum yields ranging from 1351 to 4694 mg kg-1, were benzaldehyde, phenol, indene, and acetophenone. Specifically, the total semivolatile compounds emitted after pyrolysis and combustion of starch/PVA samples represent only 38 and 50%, respectively, of those emitted with polyethylene. Further, the main PAHs were naphthalene, acenaphthylene, and phenanthrene with maximum values of 4694, 2704 and 1496 mg kg-1, respectively. The PAH yield was considerably higher in experiments with low oxygen content.


Assuntos
Poluentes Atmosféricos/química , Incineração , Álcool de Polivinil/química , Poluentes Atmosféricos/análise , Carbono/análise , Etanol/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Cloreto de Polivinila/análise , Pirólise , Amido/análise
15.
Food Chem ; 324: 126863, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32353657

RESUMO

In this study, 95 accessions of proso millet (Panicum miliaceum L.) were characterized for starch physicochemical properties, including apparent amylose content (AAC), gel textural properties, Rapid Visco Analyzer (RVA) pasting viscosity properties, thermal and retrogradation properties. Based on genotypic data, the genetic diversity and inter-relationship of these starch traits were analyzed. Diverse starch quality was found, for example, AAC ranged from 0 to 32.3%, gelatinization temperature (GT) varied from 71.5 to 79.0 ℃, and RVA profile showed distinct patterns among proso millet of different AAC types. Interestingly, high AAC proso millet usually had GT lower than that of low AAC proso millet, which is different from the findings in rice starch. Many starch traits were significantly correlated and most of the 18 tested traits could be classified as either AAC-related traits or GT-related traits. In summary, the information presented here will be useful for further development of proso millet products.


Assuntos
Panicum/química , Amido/química , Amilose/análise , Análise por Conglomerados , Géis/química , Genótipo , Oryza/química , Oryza/metabolismo , Panicum/genética , Panicum/metabolismo , Análise de Componente Principal , Amido/análise , Temperatura , Viscosidade
16.
PLoS One ; 15(5): e0232689, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32384105

RESUMO

Bacteria residing in the gastrointestinal tract of mammals are crucial for the digestion of dietary nutrients. Bacterial community composition is modified by age and diet in other species. Although horses are adapted to consuming fibre-based diets, high-energy, often high-starch containing feeds are increasingly used. The current study assessed the impact of age on the faecal bacteriome of ponies transitioning from a hay-based diet to a high-starch diet. Over two years, 23 Welsh Section A pony mares were evaluated (Controls, 5-15 years, n = 6/year, 12 in total; Aged, ≥19 years, n = 6 Year 1; n = 5 Year 2, 11 in total). Across the same 30-week (May to November) period in each year, animals were randomly assigned to a 5-week period of study and were individually fed the same hay to maintenance (2% body mass as daily dry matter intake) for 4-weeks. During the final week, 2g starch per kg body mass (micronized steam-flaked barley) was incorporated into the diet (3-day transition and 5 days at maximum). Faecal samples were collected for 11 days (final 3 days hay and 8 days hay + barley feeding). Bacterial communities were determined using Ion Torrent Sequencing of amplified V1-V2 hypervariable regions of 16S rRNA. Age had a minimal effect on the bacteriome response to diet. The dietary transition increased Candidatus Saccharibacteria and Firmicutes phyla abundance and reduced Fibrobactres abundance. At the genera level, Streptococcus abundance was increased but not consistently across individual animals. Bacterial diversity was reduced during dietary transition in Streptococcus 'responders'. Faecal pH and VFA concentrations were modified by diet but considerable inter-individual variation was present. The current study describes compositional changes in the faecal bacteriome associated with the transition from a fibre-based to a high-starch diet in ponies and emphasises the individual nature of dietary responses, which may reflect functional differences in the bacterial populations present in the hindgut.


Assuntos
Ração Animal , Carboidratos da Dieta/metabolismo , Microbioma Gastrointestinal , Cavalos/fisiologia , Amido/metabolismo , Envelhecimento , Ração Animal/análise , Animais , Carboidratos da Dieta/análise , Fibras na Dieta/análise , Fibras na Dieta/metabolismo , Fezes/microbiologia , Glucose/metabolismo , Insulina/metabolismo , Amido/análise
17.
J Food Sci ; 85(6): 1689-1698, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32458491

RESUMO

Three hulless barley varieties were grown under normal conditions during 2017/2018 and 2018/2019, to improve their agronomic yield, and to assess how the genotype influences ß-glucan contents, and its structural, thermal, rheological, and functional properties, as intended to be used in food applications. The extracted gums with hot water at 55 °C and pH 8.0, showed contents from 5.75% to 6.41% (w/w), and concentrations from 68.55% to 79.29% of ß-glucan, with some starch and protein impurities. The results of the agronomic trail indicated the highly significant (P ≤ 0.01) influence of the genotype on all studied characteristics, and on the ß-glucan contents (0.28** and 0.33** ) at both seasons. The morphology of the three gums was significantly different in the distribution and structure of networks. Peak intensities of the -OH and -CH groups and CH2 stretching were higher and wider in Giza129 and Giza131. ß-Glucan networks melt from 71.5 to 87.18 °C, and Giza131 exhibited the highest thermal stability. The aqueous dispersions (1%) of ß-glucan gums exhibited a non-Newtonian behavior, and Giza130 presented the highest significant (P ≤ 0.05) apparent viscosity (η) and foaming stability. Giza129 showed the highest significant water and fat binding capacities, whereas Giza131 showed the highest significant foaming capacity. ß-Glucan gums showed different potentials in food applications as fat replacers, stabilizers, thickeners, and foaming agents in food systems. This study suggests planting the proper barley variety in breeding and genetic improvement programs to supply the food industry with the expected ß-glucan content with consistent structural, thermal, rheological, and functional properties. PRACTICAL APPLICATION: ß-Glucans play an important technological role in processed foods. Little current information is available on ß-glucan contents, and its potentiality on food applications, as influenced by variability among hulless barley genotypes. Accordingly, knowledge of ß-glucan levels in barley varieties is a valuable attribute for both consumers and food processors, and it will create an opportunity for scientific cooperation between food technologist and breeders to identify the suitable barley varieties to be used in breeding programs, to obtain barley with required ß-glucan contents, targeted for specific end uses.


Assuntos
Hordeum/química , beta-Glucanas/química , Indústria Alimentícia , Genótipo , Hordeum/classificação , Hordeum/genética , Estrutura Molecular , Amido/análise , Viscosidade
18.
Carbohydr Polym ; 235: 115964, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32122498

RESUMO

This review focuses on cationic starches with a low degree of substitution (<0.06) which are mainly used for production of paper-based products. After a brief introduction on starch in general, cationization pathways and importance of cationic starches in paper production, this review emphasizes on the analytical challenges from different perspectives. These include the different length scales of starches when in solution: the macromolecular level, their assembly into nm aggregates and finally hydrocolloids with hundreds of nanometers of diameter. We give an overview on the current state of the art on the analysis of such challenging samples and aim at providing a guideline for obtaining and presenting reliable analytical data.


Assuntos
Papel , Amido/análise , Cátions/análise , Estrutura Molecular , Tamanho da Partícula , Propriedades de Superfície
19.
J Food Sci ; 85(4): 980-988, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32180222

RESUMO

Thermal processing of pulse crops influences the type and levels of prebiotic carbohydrates present. Pulses such as common bean and chickpea are rich sources of prebiotic carbohydrates, including sugar alcohols (SAs), raffinose family oligosaccharides (RFOs), fructooligosaccharides (FOSs), resistant starch (RS), and amylose. This study determined the changes in prebiotic carbohydrate concentrations of seven common bean and two chickpea market classes after thermal processing (cooking, cooling, and reheating). A 100-g serving of common bean provides 0.7 to 10.6 mg of SAs, 3.9 to 5.2 g of RFOs, 57 to 143 mg of FOSs, 2.6 to 3.9 g of RS, and 25 to 33 g of amylose; cooling and reheating reduced RFOs but increased SAs, FOSs, and RS in many cases. A 100-g serving of chickpea (cooked at 90 °C for 4 hr) provides 1.2 to 1.7 g of SAs, 2.5 to 3.2 g of RFOs, 26 to 43 mg of FOSs, 3.6 to 5.3 g of RS, and 24 to 30 g of amylose; cooling and reheating reduced SAs and RFOs but increased FOSs, RS, and amylose concentrations. Processing methods change the nutritional quality of pulse crops by changing the type and quantity of prebiotic carbohydrates.


Assuntos
Carboidratos/análise , Cicer/química , Phaseolus/química , Prebióticos/análise , Rafinose/análise , Amilose/análise , Culinária/métodos , Produtos Agrícolas , Temperatura Alta , Valor Nutritivo , Transição de Fase , Sementes/química , Amido/análise
20.
J Food Sci ; 85(3): 808-815, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32017102

RESUMO

When consumed as whole grain, wheat has a high nutrient density that contributes to a healthy diet. Yet, products labeled as whole wheat can still contain a substantial amount of refined grain leading to the confusion for consumers, so a method was designed to determine the whole grain status within wheat-based foods. Wheat germ agglutinin (WGA), a lectin found in the germ tissue of wheat kernels, was evaluated as a biomarker of whole grain wheat. WGA content strongly correlated with the percentage of whole wheat within premade mixtures of whole and refined (white) flours. Then, commercial flours labeled as whole wheat were tested for WGA content and found to contain up to 40% less WGA compared to a whole grain standard. Commercial pasta products labeled as whole wheat were also tested for WGA content and found to contain up to 90% less WGA compared to a whole grain standard. The differences in WGA content were not likely due to varietal differences alone, as the WGA content in common varieties used in domestic wheat flour production varied less than 25%. The levels of other constituents in wheat kernels, including starch, mineral, phytate, and total protein, were not different among the commercial whole wheat flours and pasta products. WGA is a unique biomarker that can identify wheat products with the highest whole grain content. PRACTICAL ABSTRACT: Whole grain wheat has a high nutrient density that can be part of a healthy diet, but products labeled as whole wheat can still contain some refined grain. Wheat germ agglutinin (WGA) was tested as a biomarker to measure whole grain status in wheat-based foods and revealed that some commercial whole wheat flour and pasta contained unexpectedly lower levels of the WGA biomarker compared to a whole grain standard. WGA may therefore be a useful way to test for whole grain wheat content.


Assuntos
Farinha/análise , Triticum/química , Aglutininas do Germe de Trigo/análise , Biomarcadores/análise , Minerais/análise , Amido/análise , Grãos Integrais/química
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