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1.
Agricultural lignocellulosic fiber (wood flour)‐waste was used to prepare composite materials through partial replacement of wood flour with low density polyethylene powder (LDPE) ranged from 10 to 20% by weight; these composites were made with and without electron beam irradiation (EB). The results obtained showed that, flexural strength, modulus of elasticity, modulus of rupture, and impact strength increase with increasing content of LDPE up to 20%. While, the percentages of thickness swelling and water absorption are decreased directly with increasing content of LDPE. Furthermore, the EB irradiation improves the physico‐mechanical properties of composite materials from 10 to 50 kGy. The results obtained are also confirmed by scanning electron microscopy (SEM), and thermogravimetric analysis (TGA). POLYM. COMPOS., 2008. © 2008 Society of Plastics Engineers  相似文献   

2.
Under the Food for Peace Program, whole grains, milled wheat flour, milled rice, soybean oil, soybean flour, nonfat dry milk, soyacontaining blended food supplements, and soya-fortified processed foods are provided by the U.S. to needy people abroad to alleviate malnutrition. These commodities are used in maternal/child health programs, school feeding, food for work projects and disaster relief. The wide diversity of nutritional requirements and traditional food preferences has led to development of nine soya-containing food types, which are used in the PL-480 Title II donation program as blended food supplements or fortified processed foods. Research studies have led to the development of product specifications. Blended food supplements include the standardized mixtures of corn-soya-milk (CSM), instant CSM, wheat-soy blend and whey-soy drink mix. These foods, developed to fulfill the nutritional requirements of preschool children, contain from 17.5 to 29.7% either toasted-defatted or equivalent full-fat soya flour, along with vitamins and minerals. In addition, 4–19% soya oil is added to improve caloric density. These products contain 19 or 20% minimum protein and 6 or 19% minimum fat content. Fortified processed foods include soya-fortified bulgur (SFB), soya-fortified bread wheat flour (SFWF), soya-fortified cornmeal (SFCM), soya-fortified sorghum grits (SFSG), and soya-fortified rolled oats (SFRO). These foods contain toasted soya flour, grits, or flakes added at 12–15% levels. Fortified foods are generally consumed by people other than infants.  相似文献   

3.
Food snacks using powdered residues from the orange juice industry as a source of dietary fiber were formulated. Six formulations utilizing powdered orange residues with three different moisture levels (25%, 15% and 10%) were elaborated. There were used two basic blends. The first one was 33.3% of orange dry powder, 33.3% of honey, 16.6% of roasted peanut, 16.6% of raisins; the second one was 28.6% of orange powder, 35.7% of honey, 17.85% of roasted peanut, 17.85% of raisins. Snacks had spherical shape with 2.5 cm diameter and a weight close to 10g. The snack moisture was between 12.6 and 17.4%, and their aw between 0.65 and 0.71. The snack chemical composition, on dry matter basis, was 1.6 and 1.9% of ash; 12.3 and 15.2% of lipids; 6.1 and 7.1% of proteins; and 56.2 to 59.6% of carbohydrates; the caloric contribution (calculated) was between 326.8 and 342.9 kcal/100g. The powdered orange residue had 64% of total dietary fiber, 54% of insoluble dietary fiber and 10% of soluble dietary fiber. In the snack the fiber amount fluctuated between 20 and 26% of total dietary fiber; 18 and 22% of insoluble dietary fiber, and 3.0 and 4.5% of soluble dietary fiber. The snack with the higher content of orange residue presented the higher content of dietary fiber. The snacks were well accepted by a sensory panel, without showing differences among treatments.  相似文献   

4.
The study herein reported presents information on the dietary fiber content of four food groups consumed in Central America. These are: cereals, grains and products; raw and processed beans; raw and processed vegetables, and starchy foods such as potatoes, cassava and plantain. Besides data on soluble and insoluble fiber, data on in vitro protein digestibility are included. The total dietary fiber content of the wheat flour products varied from 1.62 to 2.83% on a fresh basis, with the exception of whole-wheat bread, which showed a 7.57% content. The maize tortilla presented values ranging from 3.96 to 5.21% in respect to beans, and the values for cooked and raw beans fluctuated between 6.36 and 7.00%, independent of the color; however, fried beans reported values from 15.28 to 17.58%. Vegetables contained total dietary fiber values of 1.51 to 4.34, and the tubers, from 1.31 to 2.86%.  相似文献   

5.
Soy protein food products occupy an important place in both U.S. overseas and domestic food assistance programs. In the overseas food donation program the products serve as the source of protein for the fortification of conventional processed commodities—wheat flour, corn meal, rolled oats, bulgur, and sorghum grits—and as a major source of protein in several cereal soy products designed for special use as child food supplements. Acceptance of these products has been good and more than 1 billion lb. of soy-fortified foods were distributed in the overseas program during July 1, 1972-June 30, 1973. In domestic food assistance programs, soy protein foods which meet U.S. Department of Agriculture requirements have been introduced into both school lunch and breakfast programs and also are distributed to needy families. Two products, textured soy protein and protein-fortified enriched macaroni, are permitted to meet part of the meat requirement in the Type A school lunch. In the school breakfast program, soy protein is a permitted ingredient in protein-fortified foods such as doughnuts, cake-like baked products, and cereal-fruit products. They were introduced primarily to meet the need for nutritious food items that require no kitchen facilities to prepare and are convenient to serve in schools that lack food service facilities. Specifications for the various food products are presented.  相似文献   

6.
In this study the chemical composition and iron bioavailability of hull and hull-less soybean flour from the new cultivar UFVTN 105AP was evaluated. The hemoglobin depletion-repletion method was used in Wistar rats. Soybean hull flour presented 37% more total dietary fiber and higher content of iron than hull-less soybean flour. The phytate:iron molar ratio, however, was 2-fold lower in the soybean hull flour in compared to the hull-less soybean flour. Animals fed soybean hull flour presented hemoglobin gains similar to those of the control diet group (p > 0.05). The Relative Biological Values of hull and hull-less soybean flour were 68.5% and 67.1%, respectively, compared to the control group. Heat-treated soybean hull flour (150 degrees C/30 minutes) showed high content of iron and low phytate, which favors the iron bioavailability. Thus, the soybean hull flour is a better source of dietary fiber and iron than hull-less soybean flour at comparable bioavailabilities.  相似文献   

7.
Impact of fat substitutes on fat intake   总被引:3,自引:0,他引:3  
Dietary fat is the number one nutrition concern of Americans. In response to rising consumer demand for reduced-fat foods, the food industry has developed a multitude of nonfat, lowfat, and reduced-fat versions of regular food products. To generate reduced-fat or fat-free products that have the same organoleptic characteristics of the regular fat version, food manufactures frequently employ fat substitutes in the formulation of these foods. Fat substitutes are made from either carbohydrate, protein, or fat, or a combination of these components. Researchers have questioned the impact of fat substitutes on both fat and caloric intake. The majority of research studies in which fat substitutes were either covertly or overtly substituted for dietary fat indicate that in short-term, carefully-controlled conditions, fat substitutes can decrease both dietary fat intake and percentage of calorie intake from fat. However, individuals compensate for the caloric deficit created by the fat substitutes by increasing their consumption of other macronutrients, primarily carbohydrate. The long-term effect of fat substitutes on the fat intake of free-living individuals and weight control are unknown. People tend to eat more of a food when they know that food is reduced in fat. Fat substitutes should not be considered a substitute for sound nutrition education and a healthy lifestyle which includes regular exercise.  相似文献   

8.
In grazing systems, forage availability is a function of herbivore density, which can influence an animal's ability to be selective. In turn, the influence of food availability on selectivity has the potential to influence plant biodiversity. We hypothesized that the ability of herbivores to mix toxin-containing foods in their diets is a function of the availability of nontoxic foods and the nutritional characteristics of the toxin-containing foods. We evaluated this hypothesis in two trials simulating different diet qualities (high-quality foods in trial 1, low-quality foods in trial 2). Within each trial, the four treatment groups were offered with different amounts of nutritious, familiar foods—10, 30, 50, and 70% of ad libitum intake—but were offered with ad libitum access to toxin-containing foods. Each lamb was presented with five foods, including three toxin-containing unfamiliar foods (terpenes, tannins, and oxalates) and two nutritious familiar foods (alfalfa and barley). In trial 1, as the availability of nutritious familiar foods decreased, animals ate more of all three toxin-containing foods. As the availability of nutritious alternatives increased, the pattern of selection shifted from terpenes to tannins and oxalates. In trial 2, animals also ate more toxins as the availability of nutritious alternatives decreased, but their pattern of diet mixing changed. Low availability of nutritious alternatives resulted in the animals eating more oxalates. During preference tests when all five foods were offered ad libitum, animals fed with 10, 30, 50, and 70% of ad libitum intake from trial 1 ate 49, 47, 41, and 38% of the three toxin-containing foods, respectively. The lower diet quality in trial 2 affected intake of the toxin-containing foods such that animals fed with 10, 30, 50, and 70% of ad libitum intake ate 37, 36, 29, and 27%, respectively, of the three toxin-containing foods. Thus, the quality of toxin-containing foods and the availability of nutritious alternatives interacted to modify the pattern of diet mixing by lambs.  相似文献   

9.
There is an increasing appeal for convenience foods with potential health benefits to the consumer. Raw materials with high nutritional value and functional properties must be used on the development of these food products. Amaranth is a gluten-free grain with high nutrition value. Inulin and oligofructose are prebiotic ingredients presenting effects as the enhancement of calcium absorption. Amaranth bars enriched with inulin and oligofructose were developed in the flavors: banana, Brazilian nuts and dried grape, coconut, peach, strawberry and wall nut. The proximate composition were determined and compared to commercial cereal bars, available in traditional (n=59), light (n=60), diet (n=8), with soy (n=10) and quinoa (n=1) categories. Amaranth bars present mean global acceptance values from 6.3 to 7.6 on a 9-point hedonic scale, nutritional advantages as compared to commercial cereal bars (caloric reduction and higher levels of dietary fiber). Although amaranth is an unknown raw material in Brazil, it shows good potential to be used in the manufacturing of ready-to-eat products. As they are gluten free, these amaranth bars are also an alternative product for celiacs, also contributing to the enhancement of calcium absorption, a problem frequently observed in these patients.  相似文献   

10.
The purpose of this investigation was to evaluate the dietary score as a valid and rapid alternative procedure for the processing and analysis of food consumption data in Guatemala. The dietary score consists in assigning points to a diet based upon the number of servings the diet provides of each one of the eight groups in which food has been classified. The size of the serving for each food receiving points was estimated based on available data describing the food pattern of Guatemala. The caloric contribution of each of the eight groups to the total caloric intake was also calculated, and information on the caloric and nutrient needs of the Guatemalan population is discussed. In this communication, the dietary score was compared to the percentage of adequacy for energy and nutrients in 392 diets of women, and children between the ages of 24 and 60 months. Half of the dietaries were collected using the 24-hour recall method, while in the other half, the direct weighing method was used. Nutritional adequacy was estimated from food composition tables and based on the recommended energy and nutrient intake figures. In addition, by utilizing the adequacy indices for energy and nutrients, a binary variable was developed to describe the overall adequacy of the diet. This variable describes the probability a diet has of being adequate, given the dietary score obtained. In conclusion, the dietary score was found to be a valid, rapid and efficient alternative for the processing and evaluation of food consumption information, collected by means of either the direct weighing of foods or the 24-hour recall methods.  相似文献   

11.
Amaranth, a traditional american crop that is nowadays given renewed importance, has good food potential value. The minerals contributed by the grain are quantitatively important. However, as the flour is obtained by total grinding of the grain, this process leads to the presence of anti-nutritional components, such as fitates, and therefore, the evaluation of the actual availability of the minerals of nutritional interest becomes necessary. The process of bread fermentation, plus the addition of fitases and enhancers of mineral availability such as citric and ascorbic acid, might improve mineral bioavailability. The objective of this work was to assess protein, ash, lipids and total dietary fiber content and evaluate the concentration and dialyzability of Fe, Zn and Ca (as mineral bioavailability indicator) in bread and pasta 100% wheat, and bread and pasta obtained by replacing 20% wheat flour (WF) with whole amaranth flour (WAF). Ascorbic acid (AA), citric acid (CA) and fitase were used as mineral bioavailability enhancers. The potential contribution of each mineral (PC) was calculated as each mineral concentration times its dialyzability. In 80:20 bread an increase of total dietary fiber and minerals, compared to 100% wheat products was observed. A maximum FePC in 80:20 bread was obtained with CA and fitase (0.55mg%). In pasta, the maximum effect was observed with CA (0.07 mg%). The CaPC was maximum in 80:20 pasta with CA (16.72 mg%). The greatest ZnPC was found in 80:20 bread with CA and fitase (0.40 mg%). The introduction of the WAF in fermented baked products with addition of CA and fitase allows to obtain nutritional advantages.  相似文献   

12.
The present investigation was developed as a contribution to Guatemalan's elderly food and nutrition. Its main objective was to evaluate the chemical, nutritional and sensory quality of bread prepared from the partial substitution of wheat flour with rice flour. Wheat flour substitutions with rice flour in the order of 15, 20, 30, 40, 50 and 60% were evaluated. Differences with the control (100% wheat bread) were found during the process of preparation, as well as texture, volume, height, weight and specific volume. Important effects in dough handling were noted specifically in the 40, 50 and 60% rice bread. Thus, a sandy texture was found in breads of higher rice levels. The bread protein quality increased with the level of substitution; however the protein quality difference between the wheat bread and the bread with 60% rice flour did not achieve statistical significance. Based on a statistical analysis of the physical properties the bread with 30 and 40% rice flour was selected, and through a preference test between these last two, the 30% rice flour bread was selected as the sample best suited to the present study's purposes. This bread was not different to wheat bread in many nutritional parameters, although in others it showed to be superior. Each serving size of bread has a weight of 80 grams (2 slices) that contributes adequate quantity of calories, protein and sodium, although a little less dietary fiber than 100% wheat bread.  相似文献   

13.
杨振  陈佑宁  王欢 《应用化工》2006,35(8):632-633,639
阐述了食品添加剂的种类和作用,介绍了我国食品添加剂现状和国内外研究进展,探讨了面粉、奶粉和肉制品等食品中食品添加剂对人体安全的影响。  相似文献   

14.
The objectives were to assess total dietary fiber intake, identify the major sources of dietary fiber, and examine its association with socio-economic factors among Flemish preschoolers. Three-day estimated dietary records were collected from a representative sample of preschoolers 2.5-6.5 years old (n = 661; 338 boys, 323 girls). The mean dietary fiber intake (13.4 g/d) was lower than the intake level recommended by the Belgian Superior Health Council (70% boys and 81% girls below the guidelines). The most important contributor was the group of bread and cereals (29.5%), followed by fruits (17.8%), potatoes and grains (16.0%), energy-dense, low-nutritious foods (12.4%), and vegetables (11.8%). Multiple linear regression analyses showed that total fiber intake was associated with maternal education and parents' employment. Overall, fiber intakes from high-nutritious foods (vegetables and fruits) were higher in preschoolers of higher educated mothers and those with one or both parents being employed. In conclusion, the majority of the preschoolers had dietary fiber intakes below the recommended level. Hence, dietary fiber should be promoted among parents of preschoolers and low socio-economic status families should be addressed in particular.  相似文献   

15.
Twenty one wheat and corn based food products elaborated in Costa Rica were analyzed by chemically with the purpose of having data on local foods. The analytical methods to determine proximate composition were AOAC's. Energy was estimated by calorimetric bomb and dietary fiber (DF) by the gravimetric enzymatic method. Also food portion size was estimated and related with DF content for food classification. The values of the nutrients per food were established and compared with others reported in foreign tables commonly used in the country. Fat and energy content in cookies are higher than in salad breads and crackers. Wheat and corn based food products are classified either as low or very low DF sources (< 2.9 g FD/portion). Corn "tortilla" DF content duplicates bread's and the fiber is basically insoluble. Marked differences were founded in the nutritive composition of specific foods when compared with values reported in foreign food tables. In other foods, as corn based products, similarities in the chemical composition were common. The chemical composition of the studied local foods shows the potential of the diet to be atherogenic, an important aspect to be considered with relation to the main causes of mortality in Costa Rica population. The more compatible food composition table with our data is the Central American, followed by the Latin American one. The necessity of having data on the chemical composition of local foods has been demonstrated.  相似文献   

16.
To meet the challenge of procuring new sources of natural polymers without affecting the demands for food crops, a thermoplastic unripe banana flour (TPF) was produced, characterized, and blended with metallocene‐catalyzed polyethylene (mPE). Both the pulp and peels of unripe banana were used to produce flour, whose stability and thermoplastic properties allowed blending with mPE in high proportions, that is, 50, 60, 70, and 80%. The blends were injection molded, and the thermal, mechanical, microstructural, and infrared spectral properties of the resulting samples were characterized. The blend containing 50% TPF yielded a robust, elastic, and nonbrittle material. Maleic anhydride grafting on mPE (mPE‐g‐MA) promoted interphase adhesion of the polymers and homogeneity in the blends. Grafting also influenced the mechanical, thermal, and microstructural properties of the blends. The characteristics of the blends make them ideal for designing biodegradable plastics while exploiting banana peels, which are usually considered agricultural waste. POLYM. ENG. SCI., 55:866–876, 2015. © 2014 Society of Plastics Engineers  相似文献   

17.
The purpose of this study is to obtain a low cholesterol egg powder for the preparation of different foods for persons whose egg consumption is restricted. Egg white and yolk mixtures prepared in different proportions were dehydrated; the following dried mixtures were obtained: A (1:1), B (2:1) and C (3:1) of egg white:yolk respectively. These mixtures were evaluated using the following parameters: proximal analysis, microbiological assay and protein quality evaluation. Physical characteristics of the powder and the sensorial tests of foods prepared with these mixtures were carried out. The fat and the cholesterol content in the mixture C were decreased by 40% and 20% respectively. The microbiological tests showed that the three mixtures were safe for human consumption. The PER of sample A (whole egg) was 3.65 and for the mixture C 3:1 egg white:yolk was 3.05. The PER of the 50:50 protein mixtures eggs white and yolk: with corn lime treated flour (HMN) were higher than that of the casein standard. The sensorial tests of the foods prepared with all the mixtures were acceptable.  相似文献   

18.
The International Vitamin A Consultative Group (IVACG) developed a research instrument based on consumption of vitamin-A food sources to classify populations into groups of high, moderate and low deficiency risk in the consumption of this nutrient. The instrument was tested on a population of 91 pregnant women who attended prenatal health care service run by School of Public Health of the University of S?o Paulo. Such instrument was termed Simplified Dietary Assessment (SDA) and it is comprised of a 24-hour dietary recall--Consumption Index (CI) and consumption frequency questionnaire--Usual Food Pattern (UFP). SDA pointed out the most consumed daily and weekly foods as being milk in liquid form, tomato, lettuce, margarine and banana. All these food sources belong to groups of low and moderate vitamin A content. Assignment in risk groups was based on the recommended dietary intake proposed by the Food and Agriculture Organization of the United Nations--(FAO/OMS--1991) and two-thirds of the recommended intake was considered the cutting off point. According to data obtained by the SDA, more than 50% of the population interviewed was assigned to the High and Moderate risk groups for deficiency in vitamin A intake. Statistical analysis of the data revealed a significant statistical correlation r = 0.50 (p > 0.005) and a weighted Kappa value of (kw = 0.207), which suggests that the SDA is a useful instrument and is a reasonable means for risk assignment of vitamin A deficiency among groups with inadequate levels of intake of foods as sources of this nutrient. However, the results suggest that in order to evaluate vitamin A intake appropriately, a larger number of applications of the IC questionnaires would be required.  相似文献   

19.
The objective of this study was to evaluate four cookie formulations which wheat flour was partially substituted by free-fat corn germ flour and/or soy fiber. Baking quality, protein, fat, ash, dietary fiber, hardness, color, Protein Efficiency Ratio PER and Apparent Digestibility in vivo were determined. A trained panel evaluated color, hardness and fracturability of cookies. Dietary fiber of cookies varied from 8.2 to 24.9% and protein from 11.3 to 12.7%. The source and amount of dietary fiber modified physical, sensory, and nutritional properties of cookies. Cookies formulated with 20% corn germ flour gave the highest PER, Digestibility Aparente in vivo, and acceptance by consumers. This study demonstrated the potential use of free-fat corn germ and soy fiber as functional ingredients.  相似文献   

20.
Peanut flour has been evaluated for use in a variety of food products as a replacement for animal source proteins. In breakfast cereals and snack foods, peanut flour blends well with cereal flours to yield products with excellent flavor, texture, and color. Peanut flour can be used to produce textured vegetable protein or can be used directly in ground meats to provide good moisture and fat binding characteristics. In bakery products, peanut flour can be used at levels up to 20% to provide protein supplementation without the astringent flavor of other oilseed flours.  相似文献   

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