292 resultados para Crude desalting
Resumo:
Sixteen common bean cultivars were compared concerning the physicochemical characteristics of their raw seeds in the course of two consecutive harvests, as well as the effect of storage conditions on starch and dietary fiber content of cooked beans. Using cluster analysis it was possible to identify groups of cultivars with different nutritional features. Bean cultivars were categorized into four different groups according either to their macronutrient content (crude protein-PROT, total dietary fiber-TDF, insoluble dietary fiber-IDF, soluble dietary fiber-SDF, digestible starch-DS, and resistant starch-RS) or to their micronutrient levels (Fe, Zn, Mn, Cu, Ca, Mg, and P). Guateian 6662 and Rio Tibagi appeared to be the most suitable cultivars to prevent nutritional deficiencies, because they had high PROT, DS, Fe, and Zn content. The high total dietary fiber and RS content of Iraí, Minuano, and TPS Bonito cultivars, and specially the high soluble fiber content of Guateian 6662 and Rio Tibagi cultivars suggests that they could have a beneficial role in controlling blood lipid and glucose levels. Cooked beans had a decrease in DS and an increase in RS content after storage (4 °C or -20 °C), but these changes were more prominent in beans that had low RS content before cooking than in those of high RS content. TDF, IDF, and SDF did not change after storage.
Resumo:
Polygalacturonase production by the thermophilic Bacillus sp. SMIA-2 cultivated in liquid cultures containing 0.5% (w/v) apple pectin and supplemented with 0.3% (w/v) corn steep liquor, reached its maximum after 36 hours with levels of 39 U.mL-1. The increase in apple pectin and corn steep liquor concentrations in the medium from 0.5 and 0.3%, respectively, to 0.65%, markedly affected the production of polygalacturonase, whose activity increased four times, reaching a maximum of 150.3 U.mL-1. Studies on polygalacturonase characterization revealed that the optimum temperature of this enzyme was between 60-70 °C. Thermostability profile indicated that the enzyme retained about 82 and 63% of its activity at 60 and 70 °C, respectively, after 2 hours of incubation. The optimum pH of the enzyme was found to be 10.0. After incubation of crude enzyme solution at room temperature for 2 hours at pH 8.0, a decrease of about 29% on its original activity was observed. At pH 10.0, the decrease was 25%.
Resumo:
In recent decades, there has been an increase in the studies of isomaltulose obtainment, due to its physicochemical properties and physiological health benefits. These properties, which include low cariogenicity, low glycemic index and greater stability, allow the use of this sweetener as a substitute for sucrose in foods; besides the fact that it can be converted to isomalt, a dietary non-cariogenic sugar alcohol used in pharmaceuticals as well as in the food industry. Isomaltulose (6-O-α-D-glucopyronosyl-1-6-D-fructofuranose) is a disaccharide reducer obtained by the enzymatic conversion of sucrose - the α-glucosyltransferase enzyme. Different treatments were performed for the preparation of whole cells; lysed cells; and crude enzyme extract of Erwinia sp. D12 strain immobilized in calcium alginate. The packed bed column of granules, containing Erwinia sp. cells sonicated and immobilized in calcium alginate (CSI), reached a maximum conversion of 53-59% sucrose into isomaltulose and it presented activity for 480 hours. The converted syrup was purified and the isomaltulose crystallization was performed through the lowering of temperature. The isomaltulose crystals presented purity of 96.5%.
Resumo:
The present study aimed to evaluate the chemical properties of green corn, grown in both organic and conventional farming systems, using a completely randomized factorial design. Four corn varieties (AG 1051, BR 106, SWB 551 and VIVI) of green corn kernels were evaluated for color, proximate composition, total calories, carotenoids and bioactive amines. The farming system affected some chemical and physical characteristics of green corn, but this effect was dependent upon variety. In general, organic green corn kernels were reddish (a* color component) and had higher levels of β-carotene compared to the conventional ones, suggesting that these characteristics are related. Moreover, organic green corn had higher levels of total carbohydrates and total energy compared to conventional varieties. On the other hand, crude fiber levels were higher in conventional grains - an unexpected result that deserves further investigation. Finally, the levels of cadaverine and spermine bioactive amines were not affected either by the corn variety or by the farming system.
Resumo:
The objective of this research was to study the functional properties and proximate composition of three different flours prepared from cactus pear cladodes. Immature cactus pear cladodes were dried at 60 °C, 70 °C and 80 °C. The flours were analyzed for chemical composition, amino acid profile, fatty acid composition, functional properties and color. The analyses showed no significant differences in crude protein, total lipid, crude fiber and total ash content in the flours, possibly due to the drying temperature effect. Nevertheless, during the drying at 80 °C, a reduction of the water holding capacity (55%) was observed, along with a reduction of the green color intensity (34%) - characteristic of cactus pear. The heating produced larger concentrations of tyrosine, proline, aspartic acid, and glutamic acid. In the lipids of the flours, the most abundant fatty acids were palmitic acid (C16:0), linoleic acid (C18:2n6), linolenic acid (C18:3n3), and oleic acid (C18:1n9). The cladodes flours prepared at 60 °C presented a higher quality regarding their nutritional and functional properties.
Resumo:
The physicochemical characteristics, fatty acid, tocopherol, and carotenoid composition of a crude oil extracted from papaya (Carica papaya L.) seeds, formosa variety, were investigated. The oil yield from the seeds was 29.16%. The data obtained for the analytical indexes were in agreement with those of other edible oils. The oil obtained had high oxidation resistance (77.97 hours). The major fatty acids in total lipid were oleic (71.30%), palmitic (16.16%), linoleic (6.06%), and stearic (4.73%) acid. The α and δ-tocopherol were the predominant tocopherols with 51.85 and 18.89 mg.kg-1, respectivelly. The β-cryptoxanthin (4.29 mg.kg-1) and β-carotene (2.76 mg.kg-1) were the carotenoids quantified, and the content of total phenolic compounds was 957.60 mg.kg-1. Therefore, the potential utilization of the papaya seeds for oil production seems favorable. However, toxicological studies need to be carried out before the oil is appropriate for food applications.
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This study aims to optimize an alternative method of extraction of carrageenan without previous alkaline treatment and ethanol precipitation using Response Surface Methodology (RSM). In order to introduce an innovation in the isolation step, atomization drying was used reducing the time for obtaining dry carrageenan powder. The effects of extraction time and temperature on yield, gel strength, and viscosity were evaluated. Furthermore, the extracted material was submitted to structural analysis, by infrared spectroscopy and nuclear magnetic resonance spectroscopy (¹H-NMR), and chemical composition analysis. Results showed that the generated regression models adequately explained the data variation. Carrageenan yield and gel viscosity were influenced only by the extraction temperature. However, gel strength was influenced by both, extraction time and extraction temperature. Optimal extraction conditions were 74 ºC and 4 hours. In these conditions, the carrageenan extract properties determined by the polynomial model were 31.17%, 158.27 g.cm-2, and 29.5 cP for yield, gel strength, and viscosity, respectively, while under the experimental conditions they were 35.8 ± 4.68%, 112.50 ± 4.96 g.cm-2, and 16.01 ± 1.03 cP, respectively. The chemical composition, nuclear magnetic resonance spectroscopy, and infrared spectroscopy analyses showed that the crude carrageenan extracted is composed mainly of κ-carrageenan.
Resumo:
The objective of the present study was the isolation of a yeast strain, from citrus fruit peels, able to produce a polygalacturonase by submerged fermentation with maceration activity of raw cassava roots. Among 160 yeast strains isolated from citrus peels, one strain exhibited the strongest pectinolytic activity. This yeast was identified as Wickerhamomyces anomalus by 5.8S-ITS RFLP analysis and confirmed by amplification of the nucleotide sequence. The yeast produced a polygalacturonase (PG) in Erlenmeyer shake flasks containing YNB, glucose, and citrus pectin. PG synthesis occurred during exponential growth phase, reaching 51 UE.mL-1 after 8 hours of fermentation. A growth yield (Yx/s) of 0.43 gram of cell dry weight per gram of glucose consumed was obtained, and a maximal specific growth rate (µm) of 0.346 h-1 was calculated. The microorganism was unable to assimilate sucrose, galacturonic acid, polygalacturonic acid, or citrus pectin, but it required glucose as carbon and energy source and polygalacturonic acid or citrus pectin as inducers of enzyme synthesis. The crude enzymatic extract of Wickerhamomyces anomalus showed macerating activity of raw cassava. This property is very important in the production of dehydrated mashed cassava, a product of regional interest in the province of Misiones, Argentina.
Resumo:
The chemical composition and antioxidant capacity of five seeds, chia, golden flax, brown flax, white perilla, and brown perilla, were determined. The chemical properties analyzed included moisture, ash, crude protein, carbohydrates, total lipids, fatty acids, and antioxidant capacity (ABTS+, DPPH, and FRAP). The results showed the highest amounts of protein and total lipids in brown and white perilla. Perilla and chia showed higher amounts of alpha-linolenic fatty acid than those of flaxseed varieties, ranging between 531.44 mg g-1 of lipids in brown perilla, 539.07 mg g-1 of lipids in white perilla, and 544.85 mg g-1 of lipis in chia seed. The antioxidant capacity of the seeds, evaluated with ABTS+, DPPH , and FRAP methods, showed that brown perilla had greater antioxidant capacity when compared with white perilla, flax, and chia seeds.
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The purpose of this study was to introduce yam in the development of two new composite flours containing soy and cassava. Two composite flours were obtained after fermentation of yam, soybean, and cassava in respectively 60, 30, and 10% proportions. Two varieties of yam were used: Dioscorea alata (variety "Bete bete") and Dioscorea cayenensis (variety "Lokpa"). Proximate composition, mineral content, some anti-nutritional factors (oxalates, phenols), microbiological quality, and α-amylase digestibility were determined for the fermented and unfermented composite flours. The results indicated that for the composite flours made of D. alata and D. cayenensis, fermentation increased ash and titrable acidity. Carbohydrates, pH, and energy decreased. Crude fat content was not affected by the fermentation process. Anti-nutritional factors such as oxalates and phenols were found to decrease significantly after the fermentation of the composite flours. Fermentation increased the mineral content (Mg, K, Fe, and Ca) of the composite flours. A decrease in P and Na was observed after fermentation. The microbiological study showed that safety flours contain no potential pathogenic germs. The in vitro α-amylase digestibility of the composite flours was significantly improved after fermentation. The biochemical characteristics and good hygienic quality of the obtained flours suggest that these flours can be considered as a feeding alternative for children in poor areas where yam is produced.
Resumo:
This study developed a gluten-free granola and evaluated it during storage with the application of multivariate and regression analysis of the sensory and instrumental parameters. The physicochemical, sensory, and nutritional characteristics of a product containing quinoa, amaranth and linseed were evaluated. The crude protein and lipid contents ranged from 97.49 and 122.72 g kg-1 of food, respectively. The polyunsaturated/saturated, and n-6:n-3 fatty acid ratios ranged from 2.82 and 2.59:1, respectively. Granola had the best alpha-linolenic acid content, nutritional indices in the lipid fraction, and mineral content. There were good hygienic and sanitary conditions during storage; probably due to the low water activity of the formulation, which contributed to inhibit microbial growth. The sensory attributes ranged from 'like very much' to 'like slightly', and the regression models were highly fitted and correlated during the storage period. A reduction in the sensory attribute levels and in the product physical stabilisation was verified by principal component analysis. The use of the affective test acceptance and instrumental analysis combined with statistical methods allowed us to obtain promising results about the characteristics of gluten-free granola.
Resumo:
Akara is one of Brazil's national treasures prepared from cowpea (Vigna unguiculata L.Walp), grated onions and salt and deep-fried in crude palm oil. The results of this study on akara preparation methods showed that, in general, cowpeas were soaked for up 3 hours at room temperature, and the seed coats were then removed. The akara makers preferred the olho de pombo cultivar, because of its cream hue, or the macassar cultivar because it produces a crispier paste. The seeds purchased from street markets had lower ranges of InsP6, InsP5, and InsP4 (1.03-7.62 ∝mol.g- 1; 0.14-1.31 ∝mol.g- 1; and 0.0-0.10 ∝mol.g- 1, respectively) than both the paste and akara (6.72-19.24 ∝mol.g- 1; 1.29-4.57 ∝mol.g- 1; 0.0-0.76 ∝mol.g- 1; 3.31-13.71 ∝mol.g- 1; 0.0-4.48 ∝mol.g- 1; and 0.0-1.32 ∝mol.g- 1). These results suggest that other beans or cowpea varieties have been used in the preparation of akara and that the phytate levels do not affect its nutritional quality.
Resumo:
The antioxidant activities of ethanolic crude extract (LPCE) and its four different solvent sub-fractions (namely, diethyl ether fraction (LPDF), ethyl acetate fraction (LPEF), n-butyl alcohol fraction (LPBF) and residue fraction (LPR)) from longan pericarps were investigated employing various systems including 2,2-diphenyl-1-picrylhydrazyl (DPPH)/ 2,2'-amino-di(2-ethyl-benzothiazoline sulphonic acid-6)ammonium salt (ABTS)/hydroxyl radical scavenging activity, total phenolic content and reducing power. Each extract showed concentration-dependent antioxidant activity. LPEF showed the highest scavenging activity against DPPH, ABTS and hydroxyl radicals with EC50 values of 0.506, 0.228 and 4.489 mg/mL, respectively. LPEF showed the highest reducing power with EC50 values of 0.253 mg/mL. The next was LPDF with EC50 values of 0.260 mg/mL. LPEF possessed the highest total phenolic content (230.816 mg/g, expressed as gallic acid equivalents), followed by LPDF, LPBF, LPCE and LPR. The results suggested that longan pericarp fractions possessed significant antioxidant activities and could be a promising source of natural antioxidant.
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:
The marine bioprocessing industry offers great potential to utilize byproducts for fish meal replacement in aquafeeds. Jumbo squid is an important fishery commodity in Mexico, but only the mantle is marketed. Head, fins, guts and tentacles are discarded in spite of being protein-rich byproducts. This study evaluated the use of two jumbo squid byproduct hydrolysates obtained by acid-enzymatic hydrolysis (AEH) and by autohydrolysis (AH) as ingredients in practical diets for shrimp. The hydrolysates were included at levels of 2.5 and 5.0% of the diet dry weight in four practical diets, including a control diet without hydrolysate. Shrimp growth and survival were not significantly affected by the dietary treatments. Postharvest quality of abdominal muscle was evaluated in terms of proximate composition and sensory evaluation. Significantly higher crude protein was observed in the muscle of shrimp fed the highest hydrolysate levels, AH 5% (204.8 g kg- 1) or AEH 5% (201.3 g kg- 1). Sensory analysis of cooked muscle showed significant differences for all variables evaluated: color, odor, flavor, and firmness. It was concluded that Jumbo squid byproducts can be successfully processed by autohydrolysis or acid-enzymatic hydrolysis, and that up to 5.0% of the hydrolysates can be incorporated into shrimp diets without affecting growth or survival.