880 resultados para Vegetables and legumes
Resumo:
The purpose of this study was to determine through carotenoid analysis, the provitamin A value of two carrots (Daucus carota L.) cultivars (Brasilia and Beta3), leaves and roots, raw and submitted to two ways of cooking: boiling and microwave. Proximate analysis results are also presented for a better characterization of these vegetables (moisture, ash, lipids, proteins, fiber and total carbohydrates). The main carotenoids sources of provitamin A in this vegetable, both in leaves or roots was β-carotene and α-carotene. α-carotene shows half of the provitamin A value of β-carotene. Samples of the Brasilia cultivar presented the better provitamin A value both for leaves and roots. The results for raw samples of the Brasilia cultivar were 464.48 RE/100g for leaves and 606.42 RE/100g for roots. There were no significant losses of provitamin A with the boiling or microwave cooking methods used.
Resumo:
The purpose of this study was to determine, through beta-carotene analysis, the provitamin A value of three vegetables leaves ("serralha", celery and mint), raw and submitted to two ways of cooking: boiling and microwave. Samples of "serralha" presented the better provitamin A value beyond the three leaves analyzed: 1, 373 RE/100g for raw samples. Except for mint, it was observed a significant lost of provitamin A due the two ways of cooking.
Resumo:
The postharvest losses of horticultural products justify the use of preservation techniques. The processing not only adds value to the products, but also makes the products more convenient to the consumers. The objective of this research was to define the methodologies for the minimal processing of carrot and green pepper as to the type and intensity of the adoption of conservation techniques, and to monitor the products after processing through microbiological, physicochemical and nutritional analysis. The vegetables were washed and they were immersed in cold (7ºC) water with 100 mg L-1 free chlorine for sanitation, followed by centrifugation for 5 min. The product was put into BOPP/LDPE (biaxially orientated polypropylene/low-density polyethylene) plastic bags, which were sealed under atmospheric air, vacuum and modified atmosphere (2% O2, 10% CO2, 88% N2) and stored at 1ºC±1ºC. The approximate composition of the vegetables stayed stable during the storage period, in the three tested treatments. The contents of vitamin C for the samples of minimally processed carrot and green pepper did not present differences among treatments. The contents of beta-carotene decreased slightly during the storage period for the minimally processed carrot and green pepper. After processing, carrot and green pepper had psychrotrophic counts of 10²-10(5) and 10³-10(6) CFU g-1, respectively. Anaerobic mesophiles and total coliforms were found in green peppers, representing 1.6x10³ - 7.4x10(5) and <10.g-1 - 7.4x10(5), respectively. Total and fecal coliforms, anaerobic mesophiles and Salmonella were not found in carrots. Salmonella was not found in green pepper.
Resumo:
Baru (Dipteryx alata Vog.), a species of legume found in the Brazilian savannas, was investigated in this study for the composition of its flesh and seed. Thermal analyses, Thermogravimetry (TG), and Differential Scanning Calorimetry (DSC) were used to investigate the proteins in defatted meal, concentrate, and protein isolate. The protein concentrate was extracted at pH 10, followed by a precipitation at the isoelectric point to obtain the isolate that was spray dried. The thermogravimetric curves were obtained under a nitrogen atmosphere with a 100 mL/minutes flow. The initial, final and peak temperatures and mass loss were analyzed. Within the performed temperature ranges studied, the defatted meal and concentrate presented four steps of mass loss, while the isolate showed only two steps. The protein content of defatted meal from Baru nuts was higher than that of the isolate. On the other hand, there was a reduction in enthalpy, which suggests that the process applied to obtain the baru concentrate and isolate led to protein denaturation.
Resumo:
Cooked vegetables are commonly used in the preparation of ready-to-eat foods. The integration of cooking and cooling of carrots and vacuum cooling in a single vessel is described in this paper. The combination of different methods of cooking and vacuum cooling was investigated. Integrated processes of cooking and vacuum cooling in a same vessel enabled obtaining cooked and cooled carrots at the final temperature of 10 ºC, which is adequate for preparing ready-to-eat foods safely. When cooking and cooling steps were performed with the samples immersed in boiling water, the effective weight loss was approximately 3.6%. When the cooking step was performed with the samples in boiling water or steamed, and the vacuum cooling was applied after draining the boiling water, water loss ranged between 15 and 20%, which caused changes in the product texture. This problem can be solved with rehydration using a small amount of sterile cold water. The instrumental textural properties of carrots samples rehydrated at both vacuum and atmospheric conditions were very similar. Therefore, the integrated process of cooking and vacuum cooling of carrots in a single vessel is a feasible alternative for processing such kind of foods.
Resumo:
The objective of this study was to evaluate the effect of harvest at different times of day on the chemical and physical characteristics of vegetable-type soybean BRS 267 cultivar, harvested at the R6 stage (seed development) and to compare it with that on the grains harvested at the R8 stage (maturation). The pods of the BRS 267 cultivar were harvested at the R6 stage (at 8:00 AM, 12:00 AM, and 6:00 PM), the color parameters were evaluated, and the grains were analyzed for chemical composition, activity inhibitor trypsin, phytic acid content, starch, sugars, fatty acids, and isoflavones. No differences were observed among the different harvest times in terms of the chemical constituents of vegetable-type soybean BRS 267 cultivar harvested at the R6 stage. Isoflavones content did not change with different harvest times, and the aglycone forms (daidzein, glycitein, and genistein) were found in smaller quantities at the R6 stage compared to the R8 stage. The color of the pods of soybean BRS 267 cultivar, harvested at the R6 stage did not change with different harvest times. The grains harvested at the R6 stage had lower protein content, phytic acid, and sucrose and higher levels of lipids, carbohydrates, starch, glucose, fructose, stachyose, and linolenic acids than those collected at the R8 stage. The different times of harvest did not affect the quality of the vegetable-type soybean BRS 267 cultivar harvested at stage R6. Nevertheless, it is recommended to harvest in the morning, when the temperature is milder, like other vegetables, to facilitate and optimize its marketing and in natura consumption.
Resumo:
Fruits are important sources of nutrients in human diet, and Barbados Cherry (Malpighia glabra L.) is of particular interest due to its high content of antioxidants. Diets rich in fruits and vegetables protect individuals against diseases and cancer, but excessive intake of vitamins may act as pro-oxidant and generate changes in DNA. To evaluate the effect of different in natura (BAN) and frozen (BAF) Barbados Cherry pulp concentrations and synthetic vitamin C in liquid form (VC) on the chromosome level and the cell cycle division, root meristeme cells of Allium cepa L. and bone marrow cells of Wistar rats Rattus norvegicus, were used as test system. In Allium cepa L., BAN, at the highest concentration (0.4 mg.mL-1) and BAF, at the lowest concentration (0.2 mg.mL-1), inhibited cell division, and there was recovery of cell division after the recovery period in water only for BAN. In the Wistar rats, all treatments with Barbados Cherry, either acute or subchronic, were not cytotoxic or mutagenic; only the highest concentration of VC increased significantly the rate of chromosomal abnormalities. The data obtained are important to reinforce the use of Barbados Cherry fruit in the diet.
Resumo:
The use of colorants in products of animal origin is justified by the improvement in the color of foods since this attribute is considered a quality criterion. These additives can be produced using industrial effluents as substrates and appropriate organisms, such as Rubrivivax gelatinosus. Oxycarotenoids represent a class of carotenes responsible for the pigmentation of animals and vegetables. R. gelatinosus grows in fish industry effluent with the resulting production of a bacterial biomass containing oxycarotenoids. The purpose of this study was to compare the use of two drying processes - spray and freeze drying - to obtain powder biomass in terms of the process parameters (yield, productivity, and product recovery) and the product characteristics (color, proximate composition, and oxycarotenoids). No difference was detected in the yield between these techniques, while productivity was higher using spray drying. Higher product recovery and moisture were achieved with freeze drying, while ash was higher with spray drying. The freeze dried biomass was redder, darker and less saturated than the spray dried biomass. No difference in oxycarotenoids was detected between the biomasses. Although it results in lower recovery rate, spray drying was faster and more productive, and it provided the same yield as freeze drying, which makes it the method of choice for obtaining R. gelatinosus biomass.
Resumo:
Effects of cold storage and three common cooking practices, blanching, sauteing, and microwave cooking at different time intervals, on the content of glucosinolate (GSL) anticancer components in six Brassica vegetables were investigated. Eleven GSLs including progoitrin, glucoraphanin, sinigrin, glucoalyssin, gluconapin, glucobrassicanapin, glucoerucin, glucobrassicin, 4-methoxyglucobrassicin, gluconasturtiin, and neoglucobrassicin were quantified using LC-MS and HPLC. Storage at 4 ºC indicated no significant loss of GSLs in broccoli, kohlrabi, and cabbage, and approximately 90-100% of the total concentration of aliphatic and indolyl GSLs were detected. Interestingly, glucoraphanin and glucobrassicin, known as a cancer prevention agents, increased approximately above 50% in broccoli, kohlrabi, and cabbage, while the amount of glucobrassicin decreased by 5% in cauliflower for 5 days at 4 ºC. Blanching of broccoli at 120 sec significantly (36%) decreased total GSLs; however, sautéing and microwaving decreased by13-26%. Individual GSLs have different response at blanching. These findings suggest that different processing methods for each vegetable would be preferred to preserve the nutritional qualities.
Resumo:
Many factors impact on food consumption behaviours. The aim of the study is to determine the impact of socio-demographic and ecological factors on vegetable consumption. A 14-question questionnaire was applied on a voluntary basis to 200 individuals who accepted to participate in the study. Their socio-demographic attributes and the vegetable consumption habits of their families were determined. Their average monthly budget for vegetables is 31.82±12.72. The two attributes of purchased vegetables with most demand are cleanliness (61.5%) and freshness (22%). The maximum price per 1 kg of vegetables, which individuals with an income of 301-450 can afford, is 0.96, but for individuals with an income of > 450, it is 1.25. It was observed that the amount of purchased vegetables increased with the increase in the budget allocated for vegetables.
Resumo:
Calcium chloride is widely used in industries as a firming agent, and also to extend shelf-life of vegetables. The aim of this study was to determine, the effect of different doses of calcium chloride on biochemical and color properties of fresh-cut green bean. Fresh-cut green beans were dipped for 90 seconds in 0.5%, 1%, 2% and 3% solution of calcium chloride at 25°C. The fresh-cut green bean samples were packaged in polystyrene foam dishes, wrapped with stretch film and stored in a cold room at 5±1°C temperature and 85-90% RH. Calcium chloride treatments did not retain the green color of samples. Whiteness index, browning index and total color difference (ΔE) values of CaCl2 treated samples were high. Saturation index and hue angle were low compared to the control, especially at higher doses of CaCl2. Polyphenol oxidase (PPO) enzyme activity in samples treated with CaCl2 at 3% doses, was low at the 7th days of storage than with other treatments. Fructose and sucrose content of samples increased in all treatment groups whereas glucose level decreased during the first 4th days of storage.
Resumo:
AbstractThermal processing and production practices used in vegetables can cause changes in their phytochemical contents. Eggplant is characterized by its high antioxidant content. The objective of this work was to determine levels of anthocyanins, polyphenols, and flavonoids and antioxidant capacity in organically and conventionally grown eggplant prepared fresh or subjected to one of three thermal preparation methods: boiling, baking or steaming. The soluble and hydrolyzable polyphenols and flavonoids content were quantified by Folin-Ciocalteu and Aluminum chloride methods, respectively. Anthocyanins were quantified according to the pH differential method. Antioxidant capacity was determined by DPPH and ORAC methods. The results showed differences between organic and conventional eggplant for some variables although cultivation method did not have a consistent effect. Hydrolysable polyphenol content was greater, and soluble and hydrolysable antioxidant capacities were higher in organically grown eggplant, while anthocyanin content was greater in conventionally grown eggplant. Fresh eggplant produced under conventional cultivation had a much greater content of anthocyanins compared to that of other cultivation method-thermal treatment combination. In general, steamed eggplant contained higher total polyphenol and flavonoid levels as well as greater antioxidant capacity. Steamed eggplant from both conventional and organic systems also had high amounts of anthocyanins compared to other thermal treatments.
Resumo:
Abstract Oxygen metabolism in cells causes the production of free radicals, which produce damage, including changes in cell structure and function. Antioxidants are substances that, at low concentrations, slow down or prevent oxidation. Fruits and vegetables contribute to the dietary supply of these compounds. The flora of the Cerrado in Brazil has shown to have high levels of bioactive compounds. This study aimed to characterize the antioxidant activity of the pulp of jatobá-do-cerrado in vitro and in vivo.In vitro antioxidant activity of the aqueous, ethanol and aqueous acetone extracts was evaluated by the DPPH method. We determined total phenols by the Folin-Ciocalteu assay and tannins by the Folin-Denis method.In vivo antioxidant potential of the aqueous acetone extract was evaluated by the TBARS technique. The aqueous acetone extract had the highest antioxidant capacity, followed by the aqueous and ethanol extracts. The same pattern occurred in the extraction of phenols and in the extraction of tannins. In vivo administration of the aqueous acetone extract inhibited lipid peroxidation compared to the control group. The inhibition of peroxidation has increased by elevating the dosage concentration of the extracts, demonstrating a significant antioxidant potential in vivo as well as in vitro.
Resumo:
Abstract Germinated grains have been known as sources of Gamma-aminobutyric acid (GABA) that provide beneficial effects for human health. This study was aimed to investigate GABA production, dietary fiber, antioxidant activity, and the effect of cooking on GABA loss in germinated legumes and sesame. The highest GABA content was found in germinated mung bean, (0.8068 g kg-1, 24 h incubation) followed by germinated soybean, germinated black bean and soaked sesame. Beside GABA, dietary fiber content also increased in all grains during germination where the insoluble dietary fiber fractions were always found in higher proportions to soluble dietary fiber fractions. Our results also confirmed that germinated mung bean is a rich source of GABA and dietary fibers. Microwave cooking resulted in the smallest loss of GABA in mung bean and sesame, while steaming led to the least GABA content loss in soybean and black bean. Therefore microwave cooking and steaming are the most recommended cooking processes to preserve GABA in germinated legumes and sesame.
Resumo:
Abstract In Turkey and several Middle East countries' people consume “leblebi” which is a traditional snack food made from chickpeas (Cicer arietinum L.). Chickpea products are highly nutritive and a cheap food for human consumption and have become an essential part of daily diets in the world. The present study aims to determine the chemical, nutritional and dietary composition of fifty leblebi samples marketed in Turkey. Protein values of the leblebi ranged from 19.4 to 23.9% dehulled and 20.3 to 20.8% for nondehulled leblebi while a value of 19.1% was recorded for chickpeas. Mineral results showed that Potassium (K) was the most abundant element in leblebi ranging from 6514 to 14431 mg/kg. The amount of dietary components neutral detergent fibre (NDF), acid detergent fibre (ADF), acid detergent lignin (ADL) and cellulose did not vary much between the samples analyzed.