297 resultados para chemical score
em Scielo Saúde Pública - SP
Resumo:
The soybean is a protein source of high biological value. However, the presence of anti-nutritional factors affects its protein quality and limits the bioavailability of other nutrients. The effect of heat-treatment, 150 ºC for 30 minutes, on hulled and hull-less soybean flour from the cultivar UFVTN 105AP on urease, trypsin inhibitor activity, protein solubility, amino acid profile, and in vivo protein quality was investigated. The treatment reduced the trypsin inhibitor activity and urease, but it did not affect protein solubility. Protein Efficiency Coefficient (PER) values of the flours were similar, and the PER of the hull-less soybean flour did not differ from casein. The Net Protein Ratio (NPR) did not differ between the experimental groups. The True Digestibility (TD) of the flours did not differ, but both were lower in casein and the Protein Digestibility Corrected Amino Acid Score (PDCCAS) was lower than the TD, due to limited valine determined by the chemical score. Therefore, the flours showed reduced anti-nutritional phytochemicals and similar protein quality, and therefore the whole flours can be used as a source of high quality protein.
Resumo:
The effect of protein lupine isolate (LI) and addition of brea gum (BG) on a basic bread formulation is described. The major objective of this research was to evaluate the influence of the addition of LI on the quality and quantity of the proteins of fresh bread with BG. Protein quality was determinate by the Chemical Score method corrected for protein digestibility (CSCD%). The bread dough characteristics were determined by farinograph and alveograph. Fresh bread characterization was performed by measuring the physical parameters and evaluating the crumb structure. The effect of LI and BG on available lysine, the loss of available lysine ratio, and the chemical composition of the breads were also determined. The addition of LI on the bread formulation improved the protein content and the CSCD% of lysine. The dough with LI was less resistant to prolonged kneading and less manageable. With BG addition, the dough became stickier. The quality of fresh bread was affected by the addition of LI: the fresh bread had lower specific volume and more heterogeneous crumbs than that of the control group. The addition of BG did not influence the quality of the bread made with the mixed flour, but it had a positive effect on the loss of available lysine.
Resumo:
Considering that annatto seeds are rich in protein, the present work aimed to evaluate the biological quality of this nutrient in the meal residue originating from annatto seed processing. We determined the general composition, mineral levels, amino acid composition and chemical scores, antinutritional factors, and protein quality using biological assays. The following values were obtained: 11.50% protein, 6.74% moisture, 5.22% ash, 2.22% lipids, 42.19% total carbohydrates and 28.45% fiber. The residue proved to be a food rich in fiber and also a protein source. Antinutritional factors were not detected. The most abundant amino acids were lysine, phenylalanine + tyrosine, leucine and isoleucine. Valine was the most limiting amino acid (chemical score 0.22). The protein quality of the seed residue and the isolated protein showed no significant differences. The biological value was lower than that of the control protein but higher than that found in other vegetables. Among the biochemical analyses, only creatinine level was decreased in the two test groups compared to the control group. Enzyme tests did not indicate liver toxicity. The results showed favorable aspects for the use of annatto seed residue in the human diet, meriting further research.
Resumo:
Four formulations of mixed açaí (Euterpe oleracea) (A) and cocoa´s honey (Theobroma cacao) (CH) jellies were prepared according to the following proportions: T1 (40% A:60% CH), T2 (50% A:50% CH), T3 (60% A: 40% CH) and T4 (100% A - control). All formulations were prepared using a rate 60:40 (w/w) of sucrose and pulp, plus 0.5% pectin and the products reached to average of 65% soluble solids content. The jellies were analyzed by chemical and physicochemical (titratable acidity, pH, soluble solid content, dry matter, total protein, lipids, vitamin C and calories) and sensory characteristics; also were evaluated levels of P, K, Ca, Mg, Fe, Zn, Cu and Mn. It was used a hedonic scale of 7 points to evaluate the attributes: overall impression, spreadability, brightness, flavor, texture and color, and also was verified the purchase intention score. The titratable acidity and pH ranged from 0.46 to 0.64% and 3.35 to 3.64, respectively, that are within the range found at most fruit jellies. The soluble solids content ranged between 65.2 and 65.5 ºBrix. The sensory acceptance results showed that all treatments (T1, T2, T3 and T4) presented means of sensory attributes above 4, demonstrating good acceptance of the product, but the treatment T1 presented the higher scores for the evaluated attributes. Cocoa´s honey added a positive influence on the attributes of color, texture and spreadability.
Resumo:
Protein characterization and results of proximate composition and mineral analyses of fruit kernels of bocaiuva, Acrocomia aculeata (Jacq.) Lodd., are reported. The kernels presented high contents of oil (51.7%), protein (17.6%) and fiber (15.8%). The seeds´ soluble proteins were isolated according to their solubility. The main separated proteins were globulins (53.5%) and glutelins (40.0%). Moreover, the presence of low molecular mass proteases in these two fractions was shown by the SDS-PAGE method. The assays of protease-inhibitory and hemagglutinating activities showed that bocaiuva´s protein fractions were not resistant to trypsin or chymotrypsin activities and that both had low lectin content. The globulin in vitro digestibility assay resembled a casein standard. Neither globulin nor glutelin enzymatic hydrolyses increased significantly (p < 0.05) after heat treatment. Threonine and lysine are the most limiting amino acids, respectively from two major protein fractions of the bocaiuva kernel, globulin (47.1% amino acid score) and glutelin (49.5% amino acid score), in terms of the theoretical profiles for children in the age range of 2 to 5 years recommended by the FAO/WHO. Bocaiuva kernels are found to be rich in calcium, phosphorus and manganese compared to some fruit nuts such as cashew and coconut.
Soymilk plain beverages: correlation between acceptability and physical and chemical characteristics
Resumo:
The objective of the research was to relate the physical and chemical characteristics of soymilk plain beverages to its sensory acceptance. Five commercial products and a new product formulated based on the less accepted sample were used. The overall acceptance was evaluated by 102 assessors using a 10-point hybrid hedonic scale. The hedonic scores ranged from 3.8 (sample E) to 7.0 (A). Most assessors (55%) preferred sample A, which was viscous (26.6 cp), dark (L* = 77.7), and slightly acidic (pH = 6.6). Sample C, which had lower solid content and higher acidity, was preferred by 29% of the assessors. These two beverages showed the greatest commercial potential of the products analyzed. The least-accepted sample (E), preferred by 8% of the assessors, had a lighter color (L* = 96.8), lower viscosity (13.5 cp), higher lipid content (2.2 g/100 g), and less protein (1.68 g/100 g) than the other products evaluated. A reformulation of the least preferred product (E) with the addition of maltodextrin and also vanilla and milk flavors increased its acceptance, yielding an average score of 7.2. Overall, it was observed that a soymilk plain beverage with higher viscosity, darker color, and higher protein content best meets consumer expectations.
Resumo:
Pumpkin (Cucurbita maxima), popularly known as squash, is a widely grown vegetable in Brazil. In this study, pumpkin seed flours (PSF) with different granulometries were used: PSF 1 (medium granulometry) and PSF 2 (coarse granulometry) in the preparation of cereal bars (CB) with different combinations with brown oats. Five formulations were prepared: CB-1 (control - 25% brown oats and 0% PSF); CB-2 (12.5% PSF 1 and 12.5% brown oats); CB-3 (25% PSF 1 and 0% brown oats); CB-4 (12.5% PSF 2 and 12.5% brown oats); and CB-5 (25% PSF 2 and 0% brown oats). The acceptance test results were analyzed in a conventional preference mapping which indicated that the bars CB-2 and CB-5 received mostly the maximum hedonistic score. With the objective of developing a cereal bar replacing oats with PSF, the bars CB-2 and CB-5 were compared to the conventional bar CB-1. The cereal bars CB-2 and CB-5 showed an increase in crude protein (87.5% and 62.5%) and in dietary fiber (77% and 44%), respectively. These results allowed the classification of CB-2 and CB-5 as fiber sources; they can, therefore, be classified as light products according to the Brazilian legislation.
Resumo:
Heavy metals have been accumulating in Brazilian soils, due to natural processes, such as atmospheric deposition, or human industrial activities. For certain heavy metals, when in high concentrations in the soil, there is no specific extractant to determine the availability of these elements in the soil. The objective of the present study was to evaluate the availability of Cd, Cu, Fe, Mn, Pb and Zn for rice and soybeans, using different chemical extractants. In this study we used seven soil samples with different levels of contamination, in completely randomized experimental design with four replications. We determined the available concentrations of Cd, Cu, Fe, Mn, Pb and Zn extracted by Mehlich-1, HCl 0.1 mol L-1, DTPA, and organic acid extractants and the contents in rice and soybeans, which extracts were analyzed by ICP-OES. It was observed that Mehlich-1, HCl 0.1 mol L-1 and DTPA extractants were effective to assess the availability of Cd, Cu, Pb and Zn for rice and soybeans. However, the same was not observed for the organic acid extractant.
Resumo:
There is a great demand for simpler and less costly laboratory techniques and for more accessible procedures for orchid breeders who do not have the necessary theoretical basis to use the traditional seed and clone production methods of orchids in vitro. The aim of this study was to assess the use of sodium hypochlorite (NaClO) as a decontaminant in the process of inoculating adult orchid explants of Arundina bambusifolia and Epidendrum ibaguenses. Solutions of NaClO (1.200, 2.400, 3.600, 4.800 and 6.000 mg L-1 - equivalent to 50, 100, 150, 200 and 250 mL L-1 of commercial bleach - CB) were sprayed on the explants (1.0 mL) and the culture medium (GB5), in the presence or absence of activated charcoal (2 g L-1). The explants used were nodal segments of field-grown adult plants. The procedures for inoculating the explants were conducted outside the laminar flow chamber (LFC), except for the control treatment (autoclaved medium and explant inoculation inside the LFC). The best results for fresh weight yield, height and number of shoots were obtained using NaClO in solution at 1.200 mg L-1 (equivalent to 50 mL L-1 commercial bleach) with activated charcoal in the culture medium. Fresh weight figures were 1.10 g/jar for Arundina bambusifolia and 0.16 g/jar for Epidendrum ibaguenses. Spraying the NaClO solutions controls the contamination of the culture medium already inoculated with the explants.
Resumo:
The socioeconomic importance of sugar cane in Brazil is unquestionable because it is the raw material for the production of ethanol and sugar. The accurate spatial intervention in the management of the crop, resulting zones of soil management, increases productivity as well as its agricultural yields. The spatial and Person's correlations between sugarcane attributes and physico-chemical attributes of a Typic Tropustalf were studied in the growing season of 2009, in Suzanápolis, State of São Paulo, Brazil (20°28'10'' S lat.; 50°49'20'' W long.), in order to obtain the one that best correlates with agricultural productivity. Thus, the geostatistical grid with 120 sampling points was installed to soil and data collection in a plot of 14.6 ha with second crop sugarcane. Due to their substantial and excellent linear and spatial correlations with the productivity of the sugarcane, the population of plants and the organic matter content of the soil, by evidencing substantial correlations, linear and spatial, with the productivity of sugarcane, were indicators of management zones strongly attached to such productivity.
Resumo:
Damping off is a nursery disease of great economic importance in papaya and seed treatment may be an effective measure to control. The aim of this work was to evaluate the quality of papaya seeds treated with fungicides and stored under two environmental and packaging conditions. Additionally, the efficiency of fungicide treatments in the control of damping-off caused by Rhizoctonia solani was evaluated. Papaya seeds were treated with the fungicides Captan, Tolylfluanid and the mixture Tolylfluanid + Captan (all commercial wettable powder formulations). Seeds of the control group were not treated. The seeds were stored for nine months in two conditions: packed in aluminum coated paper and kept at 7 ± 1ºC and in permeable kraft paper and kept in non-controlled environment. At the beginning of the storage and every three months the seed quality (germination and vigor tests), emergence rate index, height, dry mass and damping of plants in pre and post-emergence (in contaminated substrate and mycelia-free substrate) were analyzed. Both storage conditions as well as the fungicide treatments preserved the germination and seed vigor. In the infested substrate, seedling emergence was favored by fungicides, but in post-emergence, fungicides alone did not control the damping off caused by R. solani. Symptoms of damping off were not observed in the clean substrate. The results showed that the fungicide treatments may be used to pretreat papaya seed for long-term storage and commercialization.
Resumo:
The increasing need for starches with specific characteristics makes it important to study unconventional starches and their modifications in order to meet consumer demands. The aim of this work was to study physicochemical characteristics of native starch and phosphate starch of S. lycocarpum. Native starch was phosphated with sodium tripolyphosphate (5-11%) added with stirring. Chemical composition, morphology, density, binding ability to cold water, swelling power and solubility index, turbidity and syneresis, rheological and calorimetric properties were determined. Phosphorus was not detected in the native sample, but the phosphating process produced modified starches with phosphorus contents of 0.015, 0.092 and 0.397%, with the capacity of absorbing more water, either cold or hot. Rheological data showed the strong influence of phosphorus content on viscosity of phosphate starch, with lower pasting temperature and peak viscosity higher than those of native starch. Enthalpy was negatively correlated with the phosphorus content, requiring 9.7; 8.5; 8.1 and 6.4 kJ g-1 of energy for the transition from the amorphous to the crystalline state for the starch granules with phosphorus contents of 0; 0.015; 0.092 and 0.397%, respectively. Cluster analysis and principal component analysis showed that starches with 0.015 and 0.092% phosphorus have similar characteristics and are different from the others. Our results show that the characteristics of phosphate modified S. lycocarpum starch have optimal conditions to meet the demands of raw materials, which require greater consistency in stickiness, combined with low rates of retrogradation and syneresis.
Resumo:
The use of cover crops in no-tillage systems (NTS) can significantly improve the soil's fertility. Thus, a study was performed to evaluate changes in chemical properties of soil caused by cover crops in a no-tillage system. The field experiment consisted of the following crop rotation: cover crops/rice/cover crops/rice. The experimental design was in randomized blocks with three replications. Treatments consisted of four cover crops (Brachiaria brizantha(Hochst. ex A. Rich.) Stapf. cv. Marandu, Brachiaria ruziziensis R. Germ. and C.M. Evrard, Panicum maximum Jacq. cv. Colonião, and Pennisetum glaucum(L.) R. Br. cv. BN-2) and fallow (control treatment). Soil samples were collected at the beginning of the summer crop in Oct 2007, Oct 2008 and Oct 2009 at 0-5 cm soil depth. The use of cover crops provided for a significant increase in the level of nutrients, soil organic matter, cation exchange capacity, and base saturation in the soil. Soil fertility improved from the first to second year with the growing of cover crops. The soil under cover crops P. glaucum, B. ruziziensis, and B. brizantha showed higher fertility than the area under fallow.
Resumo:
ABSTRACT Pathogenic fungi cause skin darkening and peach quality depreciation in post harvest. Therefore, alternative techniques to chemical treatment are necessary in order to reduce risks to human health. The aim of this study was to evaluate the effect of the application of Trichoderma harzianum in association with different fungicides applied before harvest to 'Eldorado' peaches for brown rot control and other quality parameters during storage. The treatments consisted of five preharvest fungicide applications (control, captan, iprodione, iminoctadine and tebuconazole) associated with postharvest application of T. harzianum, after cold storage (with and without application), in three evaluation times (zero, two and four days at 20 °C), resulting in a 5x2x3 factorial design. The application of T. harzianum only brought benefits to the control of brown rot when combined with the fungicide captan, at zero day shelf life. After two days, there was a greater skin darkening in peaches treated with T. harzianum compared with peaches without the treatment, except for peaches treated with the fungicide iprodione and T. harzianum The application of T. harzianum during postharvest showed no benefits for the control of brown rot, however, the association with fungicides reduced the incidence of Rhizopus stolonifer during the shelf life.
Resumo:
Treatment of mouse tail skins with hexachlorophene (1.25% w/v) in absolute methanol or 70% isopropanol suppressed Schistosoma mansoni infections by more than 95% even when the application was performed up to three days prior to exposure to cercarial suspensions by tail immersion. Treatment with concentrations of 0.313% or higher one day prior to exposure provided at least 98% protection when the treated surface was not subjected to water washes of greater duration than 1/2 hour. Tail immersion application of 1.25% hexachlorophene one day prior to exposure still provided 87-92% protection after 3 hours water wash. Wipe application of 1.25% hexachlorophene three days prior to exposure still provided 93% protection following 3 hours water wash. High cercarial recoveries from exposure tubes at the end of exposure periods indicated high antipenetrant activity for hexachlorophene. Sufficient hexachlorophene leached from treated tail skins into the surrounding water to affect subsequently added cercariae so that they were no longer infective to untreated mice.