The objective of this work was to determine the total polyphenols content and antioxidant capacit... more The objective of this work was to determine the total polyphenols content and antioxidant capacity in beverages made with panela (a natural sweetener obtained after drying the unrefined whole sugarcane juice) in order to assess their potential as sources of antioxidants. In beverages made with three panela brands (A, B and C) with lemon, tangerine and peach flavors, the total polyphenols content was determined using the Folin-Ciocalteu's reactive and antioxidant capacity was determined by three methods: antiradical efficiency DPPH, ferric reducing power (FRP) and oxygen radical absorbance capacity (ORAC). The total polyphenols content ranged from 0.76 to 1.26 EAG g/mL and 0.73 to 1.32 EAT g/mL. The lemon flavored beverage showed the highest total polyphenols content followed by tangerine and peach flavored beverages. The three beverages had a low antiradical efficiency (AE) and the antioxidant compounds present in the beverages showed a slow kinetic. The ferric reducing power ranged from 8.28 to 10.41 mmol Fe(+2)/L. The ORAC values ranged from 1,536 to 5,220 micromol ET/100 mL. The brand B showed the highest ORAC, followed by brands A and C. The brand-flavor interaction significantly affects the total polyphenols content and the EA, thermal processing also significantly affect the AE (p < 0.05). The values of polyphenols and antioxidant capacity found in the beverages made with panela indicate that they are products potentially with antioxidant capacity.
The nutritional value and proximate chemical composition of five samples of rice bran taken from ... more The nutritional value and proximate chemical composition of five samples of rice bran taken from different varieties of rice grown in Venezuela was studied. Thiamin, niacin, riboflavin and tryptophan, lysine, methionine and cystine were analyzed. The apparent protein digestibility was between 59 an 74%, and the Protein Efficiency Ratio (PER) between 1.19 and 2.31. The supplementation with threonine increased the Protein Efficiency Ratio in 12%, but supplementation with tryptophan did not improve it neither alone nor combined with threonine. Combinations with corn and soyflour that simulate formulas for infants showed that there is a protein supplementation in these mixtures. Some combinations with corn, soy flour, and rice bran had the same P.E.R. as casein. The rice bran is an excellent source of vitamins and minerals in these combinations. The results showed that rice bran has potential value for human consumption.
Cereals are an important source of macronutrients that vary with the processing and preparation b... more Cereals are an important source of macronutrients that vary with the processing and preparation before their consumption. Cooking improves the taste of food, nice and makes them nicer and more digestible. The objective was to evaluate the changes produced in the proximate composition of precooked cornmeal, white rice, pasta and baby cereals at the time of preparation at home, aiming to update and provide data to the Venezuelan Food Composition Table (TCA). Eighty-seven samples of food products were purchased among precooked cornmeal, white rice, pasta and baby cereals. The samples were acquired at government outlets (MERCAL) and supermarket chains in different areas of Caracas. Eleven lots were obtained, which were analysed raw and cooked (usual home preparation). The analyses performed were moisture, protein, fat and ash, using official methods. The percentage results indicate significant differences (p <0.05) for the evaluated parameters between raw and cooked products for different brands. All raw cereals have humidity lower than 11.12%, and show protein percentage variations from 7.07 to 15.02, fat from 1.18 to 2.50 and ash from 0.40 to 2.38 meeting the provisions of the corresponding COVENIN standard. In the samples prepared for consumption, the percentage variations are: humidity between 56.31 and 75.97, protein from 2.53 to 5.38, fat from 0.36 to 1.22, and ash from 0.16 to 0 72. The major change these foodstuffs experience by domestic food processing is the moisture (water absorption and evaporation), which dilutes and modifies the components, which in the case of proteins are reduced by more than 50%, and thus for calculating the supply of macronutrients, the content should be considered as the foodstuff is consumed. The results obtained are similar to those reported in the 2000 version of the TCA. An Venez Nutr 2011; 24(1): 27-33
The purpose of this work was the production of a beverage with a nutritive value similar to that ... more The purpose of this work was the production of a beverage with a nutritive value similar to that of milk, but available at a lower cost. A traditional beverage in Venezuela, "Chicha de Arroz" (Rice Chicha), was chosen. The various formulas studied were based on rice, non-fat milk and different kinds of soy flour, in addition to sugar, vegetable oil, vitamins, ferrous sulfate and different flavors. A product with protein and caloric values similar to those of milk was obtained. Twenty formulas were prepared and submitted to physico-chemical, microbiological and sensorial evaluations with respect to flavor, color, viscosity and stability during period of refrigeration. The most adequate formula was prepared on a pilot-plant scale. Rat assays gave the same PER results as those of casein. Consumer acceptability was tested on 1,080 school children, and showed to be greater than 95%. The stability was superior to that of milk and the cost, approximately three-fourths that of the latter. In the school-snack program of the National Institute of Nutrition, milk is now being replaced by this Chicha.
Color loss of a dietetic formulae based on pumpkin (Cucurbita maxima), rice, hen and vegetable oi... more Color loss of a dietetic formulae based on pumpkin (Cucurbita maxima), rice, hen and vegetable oils was evaluated. The product was under an accelerated test at temperatures of 40, 50 and 70 degrees C for a month. The kinetic reaction of color loss (quality loss indicator) was obtained with n = 1 and Ea = 11.5 Kcal/mol. The product was also stored for sixth months at temperatures of 25, 30, 35 and 40 degrees C using glass containers, laminated and composite cans (non metallic). The color was measured by a colorimetric method and by sensory evaluation under the defined conditions of time, temperature and package. The statistical analyses of the color loss measured by instrument was performed by a randomized block design with a significance level of p < 0.05. The results obtained both by the instrument and by the sensory evaluation method, showed that the temperature and storage time has significant effect (p < 0.05) on the other hand, the package does not have a significant effect. It was concluded from this study that the product could be stored for 6 months at temperatures below 35 degrees C without changes in color.
The objective of this work was to develop a new kind fermented dairy drink, partially substituted... more The objective of this work was to develop a new kind fermented dairy drink, partially substituted with clear varieties of Phaseolus vulgaris (caraota) and Vigna sinensis (frijol). The formulation of fermented dairy drinks included sterile extracts of caraota and frijol, as partial substitutes which replaced milk: 10, 20 and 30%. The mixtures were inoculated with 2% of a mixture of Lactobacillus acidophillus, Streptococcus thermophilus and Bifidobacterium sp. and were incubated at 42 degrees C for 7 hours. Mango and guava jams were used as flavorings at 20%. On the basis of the sensorial evaluation the mixtures 10% frijol-mango, 10% frijol-guava, 30% caraota-mango and 20% caraota-guava were selected. In the selected fermented dairy drinks, the levels of protein, soluble and insoluble fiber, available and resistant starches were increased and the protein digestibility was 81%. The technical feasibility of partial substitution of milk with extracts of Phaseolus vulgaris or Vigna sinensis. For the elaboration of a fermented dairy drink similar to the liquid yogurt kind was demonstrated.
Deffated corn germ is a subproduct in the production of raw or precooked corn flour and of corn o... more Deffated corn germ is a subproduct in the production of raw or precooked corn flour and of corn oil. This subproduct is used only in the production of animal feed because it is a heterogeneous material with a lot of bran. The principal obstacle for direct use of deffated corn germ in the formulation of foods is the presence of fragments of hull fiber. These fragments modifies the sensorial and functional characteristics of the product. In order to avoid this problem, the deffated corn germ was processed to eliminate the fragments of fiber and to increase the protein concentration. The extractable material (ME) high in oil and the industrial deffated corn germ were fractionated by separation with sieves, aspiration, and milling. The yield of the deffated fractions of corn germ flour in the laboratory (GD1) and at the industrial level (GD2) were 44.70% and 78.02% respectively. Fiber content was reduced by 18.45% and 41.61% and protein content was increased by 7.40% and 19.56% respectively. Protein quality determined as PER (protein efficient ratio) increased from 2.57 to 2.84. Protein efficient ratio was 16 times higher than that of endosperm corn flour (PER 0.16). Apparent digestibility of both fractions were higher than 86%. Results suggests that fractioning is a simple technology that could improve the protein quality of germ as well as its color, index of solubility and water absortion.
In this study, flours from manaca or acai (Euterpe oleracea Mart), sweet potato (Ipomea batatas),... more In this study, flours from manaca or acai (Euterpe oleracea Mart), sweet potato (Ipomea batatas), and yam (Dioscorea spp.), species grown in the Venezuelan Amazon, were obtained. The proximal composition, water activity (a(w)), Fe, Ca, Zn, Mg, Cu, Na and K content were determined for the flours of manaca, sweet potato and yam. These flours were used as ingredients of products for the inhabitants of the indigenous populations of the Venezuelan Amazon (Piaroa and Hiwi). Two types of products that traditionally contain wheat flour in their formulation (ingredient they know by transculturation) were formulated; an attempt to substitute it totally or partially by the manaca, sweet potato and/or yam flours was made. For the selection of the products to be formulated, the preferences and eating habits of the indigenous communities and ease and simplicity of the preparations to be developed, were considered. The two products formulated were cookies and "small cakes". To decide on the formulation(s) of the final product(s), sensorial evaluations were made in the laboratory and in the indigenous communities Piaroa and Hiwi. High fat content (16%), dietetic fiber (59.7%) and iron (25 mg / 100 g) in manaca or acai flour were remarkable. Two types of cookies and two of "small cakes" were equally accepted by the indigenous communities. Cookies supply a high iron amount (about 24%). The feasibility of substituting the wheat flour by manaca, sweet potato and yam flour in products accepted by two ethnic populations of the Venezuelan Amazon was demonstrated.
The objective of this work was to determine the total polyphenols content and antioxidant capacit... more The objective of this work was to determine the total polyphenols content and antioxidant capacity in beverages made with panela (a natural sweetener obtained after drying the unrefined whole sugarcane juice) in order to assess their potential as sources of antioxidants. In beverages made with three panela brands (A, B and C) with lemon, tangerine and peach flavors, the total polyphenols content was determined using the Folin-Ciocalteu's reactive and antioxidant capacity was determined by three methods: antiradical efficiency DPPH, ferric reducing power (FRP) and oxygen radical absorbance capacity (ORAC). The total polyphenols content ranged from 0.76 to 1.26 EAG g/mL and 0.73 to 1.32 EAT g/mL. The lemon flavored beverage showed the highest total polyphenols content followed by tangerine and peach flavored beverages. The three beverages had a low antiradical efficiency (AE) and the antioxidant compounds present in the beverages showed a slow kinetic. The ferric reducing power ranged from 8.28 to 10.41 mmol Fe(+2)/L. The ORAC values ranged from 1,536 to 5,220 micromol ET/100 mL. The brand B showed the highest ORAC, followed by brands A and C. The brand-flavor interaction significantly affects the total polyphenols content and the EA, thermal processing also significantly affect the AE (p < 0.05). The values of polyphenols and antioxidant capacity found in the beverages made with panela indicate that they are products potentially with antioxidant capacity.
The nutritional value and proximate chemical composition of five samples of rice bran taken from ... more The nutritional value and proximate chemical composition of five samples of rice bran taken from different varieties of rice grown in Venezuela was studied. Thiamin, niacin, riboflavin and tryptophan, lysine, methionine and cystine were analyzed. The apparent protein digestibility was between 59 an 74%, and the Protein Efficiency Ratio (PER) between 1.19 and 2.31. The supplementation with threonine increased the Protein Efficiency Ratio in 12%, but supplementation with tryptophan did not improve it neither alone nor combined with threonine. Combinations with corn and soyflour that simulate formulas for infants showed that there is a protein supplementation in these mixtures. Some combinations with corn, soy flour, and rice bran had the same P.E.R. as casein. The rice bran is an excellent source of vitamins and minerals in these combinations. The results showed that rice bran has potential value for human consumption.
Cereals are an important source of macronutrients that vary with the processing and preparation b... more Cereals are an important source of macronutrients that vary with the processing and preparation before their consumption. Cooking improves the taste of food, nice and makes them nicer and more digestible. The objective was to evaluate the changes produced in the proximate composition of precooked cornmeal, white rice, pasta and baby cereals at the time of preparation at home, aiming to update and provide data to the Venezuelan Food Composition Table (TCA). Eighty-seven samples of food products were purchased among precooked cornmeal, white rice, pasta and baby cereals. The samples were acquired at government outlets (MERCAL) and supermarket chains in different areas of Caracas. Eleven lots were obtained, which were analysed raw and cooked (usual home preparation). The analyses performed were moisture, protein, fat and ash, using official methods. The percentage results indicate significant differences (p <0.05) for the evaluated parameters between raw and cooked products for different brands. All raw cereals have humidity lower than 11.12%, and show protein percentage variations from 7.07 to 15.02, fat from 1.18 to 2.50 and ash from 0.40 to 2.38 meeting the provisions of the corresponding COVENIN standard. In the samples prepared for consumption, the percentage variations are: humidity between 56.31 and 75.97, protein from 2.53 to 5.38, fat from 0.36 to 1.22, and ash from 0.16 to 0 72. The major change these foodstuffs experience by domestic food processing is the moisture (water absorption and evaporation), which dilutes and modifies the components, which in the case of proteins are reduced by more than 50%, and thus for calculating the supply of macronutrients, the content should be considered as the foodstuff is consumed. The results obtained are similar to those reported in the 2000 version of the TCA. An Venez Nutr 2011; 24(1): 27-33
The purpose of this work was the production of a beverage with a nutritive value similar to that ... more The purpose of this work was the production of a beverage with a nutritive value similar to that of milk, but available at a lower cost. A traditional beverage in Venezuela, "Chicha de Arroz" (Rice Chicha), was chosen. The various formulas studied were based on rice, non-fat milk and different kinds of soy flour, in addition to sugar, vegetable oil, vitamins, ferrous sulfate and different flavors. A product with protein and caloric values similar to those of milk was obtained. Twenty formulas were prepared and submitted to physico-chemical, microbiological and sensorial evaluations with respect to flavor, color, viscosity and stability during period of refrigeration. The most adequate formula was prepared on a pilot-plant scale. Rat assays gave the same PER results as those of casein. Consumer acceptability was tested on 1,080 school children, and showed to be greater than 95%. The stability was superior to that of milk and the cost, approximately three-fourths that of the latter. In the school-snack program of the National Institute of Nutrition, milk is now being replaced by this Chicha.
Color loss of a dietetic formulae based on pumpkin (Cucurbita maxima), rice, hen and vegetable oi... more Color loss of a dietetic formulae based on pumpkin (Cucurbita maxima), rice, hen and vegetable oils was evaluated. The product was under an accelerated test at temperatures of 40, 50 and 70 degrees C for a month. The kinetic reaction of color loss (quality loss indicator) was obtained with n = 1 and Ea = 11.5 Kcal/mol. The product was also stored for sixth months at temperatures of 25, 30, 35 and 40 degrees C using glass containers, laminated and composite cans (non metallic). The color was measured by a colorimetric method and by sensory evaluation under the defined conditions of time, temperature and package. The statistical analyses of the color loss measured by instrument was performed by a randomized block design with a significance level of p < 0.05. The results obtained both by the instrument and by the sensory evaluation method, showed that the temperature and storage time has significant effect (p < 0.05) on the other hand, the package does not have a significant effect. It was concluded from this study that the product could be stored for 6 months at temperatures below 35 degrees C without changes in color.
The objective of this work was to develop a new kind fermented dairy drink, partially substituted... more The objective of this work was to develop a new kind fermented dairy drink, partially substituted with clear varieties of Phaseolus vulgaris (caraota) and Vigna sinensis (frijol). The formulation of fermented dairy drinks included sterile extracts of caraota and frijol, as partial substitutes which replaced milk: 10, 20 and 30%. The mixtures were inoculated with 2% of a mixture of Lactobacillus acidophillus, Streptococcus thermophilus and Bifidobacterium sp. and were incubated at 42 degrees C for 7 hours. Mango and guava jams were used as flavorings at 20%. On the basis of the sensorial evaluation the mixtures 10% frijol-mango, 10% frijol-guava, 30% caraota-mango and 20% caraota-guava were selected. In the selected fermented dairy drinks, the levels of protein, soluble and insoluble fiber, available and resistant starches were increased and the protein digestibility was 81%. The technical feasibility of partial substitution of milk with extracts of Phaseolus vulgaris or Vigna sinensis. For the elaboration of a fermented dairy drink similar to the liquid yogurt kind was demonstrated.
Deffated corn germ is a subproduct in the production of raw or precooked corn flour and of corn o... more Deffated corn germ is a subproduct in the production of raw or precooked corn flour and of corn oil. This subproduct is used only in the production of animal feed because it is a heterogeneous material with a lot of bran. The principal obstacle for direct use of deffated corn germ in the formulation of foods is the presence of fragments of hull fiber. These fragments modifies the sensorial and functional characteristics of the product. In order to avoid this problem, the deffated corn germ was processed to eliminate the fragments of fiber and to increase the protein concentration. The extractable material (ME) high in oil and the industrial deffated corn germ were fractionated by separation with sieves, aspiration, and milling. The yield of the deffated fractions of corn germ flour in the laboratory (GD1) and at the industrial level (GD2) were 44.70% and 78.02% respectively. Fiber content was reduced by 18.45% and 41.61% and protein content was increased by 7.40% and 19.56% respectively. Protein quality determined as PER (protein efficient ratio) increased from 2.57 to 2.84. Protein efficient ratio was 16 times higher than that of endosperm corn flour (PER 0.16). Apparent digestibility of both fractions were higher than 86%. Results suggests that fractioning is a simple technology that could improve the protein quality of germ as well as its color, index of solubility and water absortion.
In this study, flours from manaca or acai (Euterpe oleracea Mart), sweet potato (Ipomea batatas),... more In this study, flours from manaca or acai (Euterpe oleracea Mart), sweet potato (Ipomea batatas), and yam (Dioscorea spp.), species grown in the Venezuelan Amazon, were obtained. The proximal composition, water activity (a(w)), Fe, Ca, Zn, Mg, Cu, Na and K content were determined for the flours of manaca, sweet potato and yam. These flours were used as ingredients of products for the inhabitants of the indigenous populations of the Venezuelan Amazon (Piaroa and Hiwi). Two types of products that traditionally contain wheat flour in their formulation (ingredient they know by transculturation) were formulated; an attempt to substitute it totally or partially by the manaca, sweet potato and/or yam flours was made. For the selection of the products to be formulated, the preferences and eating habits of the indigenous communities and ease and simplicity of the preparations to be developed, were considered. The two products formulated were cookies and "small cakes". To decide on the formulation(s) of the final product(s), sensorial evaluations were made in the laboratory and in the indigenous communities Piaroa and Hiwi. High fat content (16%), dietetic fiber (59.7%) and iron (25 mg / 100 g) in manaca or acai flour were remarkable. Two types of cookies and two of "small cakes" were equally accepted by the indigenous communities. Cookies supply a high iron amount (about 24%). The feasibility of substituting the wheat flour by manaca, sweet potato and yam flour in products accepted by two ethnic populations of the Venezuelan Amazon was demonstrated.
Uploads