Dietary fiber in fruits cultivated in Chile

The objective of this study was to determine the total, soluble and insoluble dietary fiber contents in fruits produced in Chile. The analyses were conducted in the fruits as eaten. Thirty eight fruits obtained from local markets and the Instituto de Investigaciones Agropecuarias (INIA) were studied. Water and total, soluble and insoluble dietary fiber were determined in the edible part of each sample. Moisture ranged between 73.1 and 92.4 g/100g. Average (+/- sd) total, soluble and insoluble contents, expresed as g/100 g on wet basis were: 2.41 +/- 1.26, range 0.30 - 5.62; 0.73 +/- 0.50 range 0.07 -2.26 and 1.68 +/- 0.89, range 0.15 -3.36 respectively. On dry weight basis total fiber concentration was 16.5 +/- 8.8, with a proportion of 69.2 +/- 11.2% and 30.8 +/- 11.2% of the insoluble and soluble form, respectively. Dietary fiber supply ranged between 0.6 to 8.4 g in the medium serving sizes. The ratios insoluble fiber/ crude fiber and total fiber/crude fiber did not present constant results. Values ranged between 1.1 and 4.9 (mean 2.5 +/- 1.1) in the former, and from 1.6 to 8.0 (mean 3.6 +/- 1.7) in the latter. It is concluded that both soluble and insoluble fiber vary widely among vegetables fruits produced in Chile. This study provides information on the fiber composition of fruits. Such information may help to choose them according to these variables in order to be used in the prevention or treatment of selected pathologies.     

Dietary fiber in vegetables cultivated in Chile

The objective of this study was to determine the soluble, insoluble, and total dietary fiber contents in vegetables produced in Chile. The analyses were conducted in the vegetables in the same conditions as they are consumed. Thirty-three vegetables obtained from local markets and the Instituto de Investigaciones Agropecuarias (INIA) were studied. Water and fiber contents were determined in 16 raw and 17 cooked (boiled) samples. Moisture range between 63.2% and 96.2%. Average (+/- sd) total, soluble and insoluble contents, expressed as g% on wet basis were: 3.00 +/- 1.59, range 0.96 7.3; 0.93 +/- 0.50 range; 0.30 2.60, and 2.06 +/- 1.26, range 0.51-5.90 respectively. On dry weight basis total fiber concentration was 30.1 +/- 12.5, with a proportion of 68.5% and 31.5% of the insoluble and soluble form, respectively. On dry weight basis total fiber concentration was 30.1 +/- 12.5, with a proportion of 68.5% and 31.5% of the insoluble and soluble form, respectively. Dietary fiber supply ranged between 1.0 to 10.7 g in the large serving sizes. The ratios insoluble fiber/crude fiber and total dietary fiber/crude fiber did not present constant results. Values ranged between 1.1 and 4.5 (mean 2.2 +/- 1.0) in the former, and from 1.4 to 6.5 (mean 3.2 +/- 1.5) in the latter. We conclude that both soluble and insoluble fiber vary widely among vegetables produced in Chile. This study provides information on the fiber composition of vegetables. Such information may help to choose them according to these variables in order to be used in the prevention or treatment of selected pathologies.     

Sheep food repellents: Efficacy of various products,habituation, and social facilitation

The study of food repulsion in ungulates is of practical importance for controlling browsing damage to forest trees and agricultural crops. Experiments with domestic sheep assessed the repulsive value of three natural and two synthetic products, using a food-choice situation. Animals were individually presented with two troughs, each containing 30 g of maize, one treated with a chemical product, and the other a control. The odor of domestic dog feces appeared to be highly repulsive, as none of the treated food was eaten, whereas 3 g ±9 and 6 g ±10 were eaten, respectively, of food treated with fetal fluids from sheep and odor of pig feces. Synthetic odors of lion feces and a commercial deer repellent were less efficient as repellents with 11 g ±13 and 14 g ±15 of food eaten, respectively. Habituation to three of the repellents was tested for a minimum of seven successive days. With dog feces, no habituation to the odor was observed. On the contrary, significant habituation (P < 0.05) was observed as early as the third trial for sheep fetal fluids and the fourth trial for the commercial repellent. To test for the effects of social facilitation, groups of four sheep including no, one, or two anosmic animals were presented with food treated with the odor of dog feces. No social facilitation was observed as none of the intact sheep ate any of the food, although the anosmic animals actively ate it throughout the test. In individual food choice tests, the odor of dog feces appeared to be an especially efficient repellent when compared with the other natural or synthetic products. Such repulsion was nearly complete, and neither habituation nor social facilitation could be observed.     

Dietary fiber content and nitrogen digestibility in Central American foods: Guatemala

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%.     

食品、生物样品和药物中抗坏血酸的检测

综述了近年来食品、生物样品和药品中抗坏血酸的各种检测方法，包括分光光度法、电化学法、酶方法和色谱法等。     

Wheat gluten applications in food products

Vital wheat gluten has traditionally been noted for its functional benefits in various bakery applications. In recent years extensive research and development work has taken place to more clearly identify wheat gluten’s unique characteristics and functional properties. As a result, many new and novel applications have been developed. The on-going potential of this exciting protein ingredient, in its native or modified forms, will only be limited by the imagination of those formulating new products.     

Dietary fiber intake and reduced risk of ovarian cancer: a meta-analysis

Background

Epidemiological studies regarding the association between dietary fiber intake and ovarian cancer risk are still inconsistent. We aimed to review the available evidence and conduct a dose-response meta-analysis to investigate the relationship between dietary fiber intake and ovarian cancer risk.

Methods

Relevant studies were identified by searching PubMed, EMBASE, and the Cochrane Library databases before August 2017. Studies that reported relative risk (RR) estimates with 95% confidence intervals (CIs) for the association between dietary fiber intake and risk of ovarian cancer were included. Random-effects models were used to combine the estimated effects extracted from individual study.

Results

Thirteen studies, with a total of 5777 ovarian cancer cases and 142,189 participants, met the inclusion criteria. The pooled multivariable RRs of ovarian cancer for the highest vs. the lowest category of dietary fiber intake was 0.78 (95% CI: 0.70, 0.88) with no evidence of heterogeneity (I² =?4.20%, P?=?0.40). Our dose-response analysis also showed a significant inverse association between dietary fiber intake and ovarian cancer risk (an increment of 10 g/day; combined RR: 0.88; 95% CI: 0.82, 0.93). There was no evidence for a nonlinear association (P for nonlinearity?=?0.83).

Conclusions

This meta-analysis suggests a significant inverse dose-response association between dietary fiber intake and ovarian cancer risk. Further studies with prospective design that take account of more potential confounders are warranted to confirm this association.

     

与食品接触橡胶制品中N-亚硝胺的来源、危害及控制

文中介绍了与食品接触橡胶制品中N-亚硝胺的来源、危害及控制手段。根据国外对N-亚硝胺限量的规定,提出了对N-亚硝胺控制的建议。     

Stability of coconut oil in food products

The active oxygen method (AOM) stability of refined coconut oil is generally 250 hr; however, samples with as low a stability as 30 hr have been obtained. The addition of BHA, BHT and citrate increased the AOM stability to about 350 hr even though the initial stability was 30 or 250 hr. Refined coconut oil samples which hydrolyzed from 2 to 10 times as rapidly as normal oils have been encountered. Such samples are undesirable for food production as soapy off-flavors may be produced. The rate of hydrolysis of coconut oil samples was evaluated by a simple laboratory test. Coconut oil free fatty acids produced a soapy off-flavor at a lower level in sweet foods than in salty ones. Soapy off-flavors were produced in a low moisture food containing coconut oil by the lipase activity of cinnamon.     

Textured and shaped oilseed protein food products

The major emphasis in developing textured and shaped protein foods has been with the use of soy proteins. The availability at a low stable price, the high protein content and quality, and the inherent chemical properties of the protein allowing for unique structure development are major reasons for its strong world-wide use. The changing economic trends of many basic protein foods are creating a need for the use of unique textured proteins either as ingredients in existing foods or allowing improved functionality in new products. The two main procedures for texturing and shaping oilseed protein are spinning of protein isolates, and direct extrusion of flour. The spinning technique is more expensive and has greater product functionality in contrast to the direct extrusion method. Consumer acceptance is in large part correlated with the technological success of imparting desirable colors, flavors and textural properties in the finished food product. Examples of these variations are given. The use level of these textured proteins, particularly in meat products, are restricted by labeling standards. The present regulations are not clearly defined. Current proposals for labeling textured vegetable proteins when used with meat products involve standards on a ratio to meat basis. One of 21 papers presented at the Symposium, “Oilseed Processors Challenged by World Protein Need,” ISF-AOCS World Congress, Chicago, September 1970.     

Palm oil and palm kernel oil in food products

Cocoa butter equivalent (CBE) formulation, especially the compatibility of palm oil based CBE with cocoa butter, is of special interest to chocolate manufacturers. Traditionally palm oil is fractionated to obtain high-melting stearin and olein with a clear point of around 25 C, the latter serving as cooking oil. Recently, palm oil has been fractionated to recover an intermediate fraction known as palm mid-fraction (PMF), which is suitable for CBE formulations. Generally, production of PMF is based on a three-step procedure. However, a dry fractionation system, which includes selective crystallization and removal of liquid olein by means of a hydraulic press, has been developed. Iodine value, solid content (SFI) at different temperatures, cooling curves (Shukoff 0°) and triglyceride/fatty acid composition determination confirmed effectiveness of the procedure followed. A direct relationship between yield, quality of PMF and crystallization temperature during fractionation has been achieved. Yield of 60% for olein of IV 64–67 has been achieved. Yield of 30% for PMF of IV 36–38 and 10% for high melting stearin of IV of 20–22 are also being achieved. High-melting stearin may be used in oleochemical applications, soaps, food emulsifiers and other industrial applications such as lubricating oil. Olein fraction, especially after flash hydrogenation thereby reducing the IV to 62/64, has excellent frying and cooking oil characteristics. Palm olein is also suitable as dietary fat and in infant formulation. Studies on interesterification of high-melting stearin with olein showed possibilities to formulate hardstocks for margarine and spread formulations, even without using hydrogenated fat components. Palm kernel and coconut fats or fractions or derived products are used for confectionery products as partial CB replacers and as ice cream fats and coatings. Coconut oil also serves as a starting material for the production of medium-chain triglycerides.     

Soy flour and grits for use in food products

Processing alternatives enable the soybean processor to manufacture soy flour products which vary in fat content, granulation and degree of heat treatment. By controlling these variables, the processor is able to regulate the nutritional value and functional properties of these products. The application of soy flour products is dependent upon their functional properties, nutritional value and low cost. Currently, the major markets for soy flour and grits are in pet foods and animal feeds, cereal based foods and ingredients, meat based foods, and as a substrate for refined protein products such as the textured vegetable proteins, soy protein concentrates, isolates and hydrolysates. These soy protein products are generally marketed as functional and nutritional substitutes for meat, milk and egg protein. For example, soy flour is a functional replacement for milk in many cereal-based foods, e.g., bread, and also enhances the nutritional value of the cereal protein by supplying lysine to the formulation. The United States government has pioneered the development and marketing of protein-enriched, cereal-based foods designed to combat worldwide starvation. The government has directly supported the research and development of corn and wheat-based food substrates supplemented with soy flour, and has purchased over one billion pounds of these products since 1966 for worldwide distribution. One of 21 papers presented at the Symposium, “Oilseed Processors Challenged by World Protein Need,” ISF-AOCS World Congress, Chicago, September 1970.     

Dietary records used for food consumption evaluation in adolescents: comparison among methods

Given the difficulties surrounding evaluating food consumption, specifically during adolescence, the goal of the present study was to compare different dietary assessment instruments used for this age group. The study was carried out with a group of 60 female adolescents between 14 and 18 years of age. Three repetitions of 24-Hour Recall, three-day Dietary Records and Purchase List of the adolescents and their families were collected. The 24 Hour Recall and Dietary Records had good repeatability, allowing to infer that only one application of one of these instruments was capable of reflecting the ingestion average (or median) of the study population group. The Purchase List allowed us to know the food availability within the context of the individual's conditions. All dietary assessment instruments may contain errors, therefore the choice of the most adequate method must rely on the objectives of the study being developed, as well as the study population.     

气相色谱法测定水产品中硝基苯残留量

本文建立了一种测定水产品中硝基苯残留量的气相色谱-质谱法。样品用乙腈提取,经液液分配后,用中性Al2O3固相萃取柱净化,利用气相色谱-质谱仪测定,外标法定量。硝基苯的浓度在0.005～1.000μg·mL-1范围内时,其相关系数和回归方程分别为r=0.99994和y=8555.93x-30.11。样品平均加标回收率在71.2%～93.6%之间,相对标准偏差为3.34%～4.18%。方法的最低检出限0.002mg·kg-1。     

Shrinkage anisotropy in fiber reinforced injection molded products

This paper includes a systematic study of the effect of fiber concentration and molding conditions on fiber orientation and shrinkage in injection molded composites. Closed-form expressions were derived to relate shrinkage and internal stresses to the molding pressure and fiber orientation. The shrinkage predictions were seen to agree well with experimentally measured shrinkages.     

A review of antioxidant analysis in food products

To permit proper usage of antioxidants by the food processor and permit control under applicable governmental regulations, it is necessary to have adequate analytical methods. Such methods should both positively identify and provide a quantitative assay for the additive. Due to the complex nature of foods, analysis of an antioxidant in the very small quantities used presents a very real problem. Solvent extraction and/or steam distillation techniques are employed to separate the antioxidants from the food. Ultraviolet spectra, gas chromatography and colorimetric techniques are used to identify and determine the quantity of each antioxidant present. Slight variations are necessary for each type of food.     

Dietary trans fatty acids: Review of recent human studies and food industry responses

Dietary trans FA at sufficiently high levels have been found to increase low density lipoprotein (LDL)-cholesterol and decrease high density lipoprotein (HDL)-cholesterol (and thus to increase the ratio of LDL-cholesterol/HDL-cholesterol) compared with diets high in cis monounsaturated FA or PUFA. The dietary levels of trans FA at which these effects are easily measured are around 4% of energy or higher to increase LDL-cholesterol and around 5 to 6% of energy or higher to decrease HDL-cholesterol, compared with essentially trans-free control diets. Very limited data at lower levels of intake (less than 4% of energy) are available. Most health professional organizations and some govemments now recommend reduced consumption of foods containing trans FA, and effective January 1, 2006, the U.S. Food and Drug Administration requires the labeling of the amounts of trans FA fer serving in packaged foods. In response, the food industry is working on ways to eliminate or greatly reduce trans FA in food products. Current efforts focus on four technological options: (i) modification of the hydrogenation process, (ii) use of interesterification, (iii) use of fractions high in solids from natural oils, and (iv) use of trait-enhanced oils. Challenges to the food industry in replacing trans FA in foods are to develop formulation options that provide equivalent functionality, are economically feasible, and do not greatly increase saturated FA content.