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.     

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.     

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.     

Fatty acid profile in baby food products

The fatty acid composition in the lipid phase of 64 commercially available baby food products, of two different batches each, was analyzed. They comprised vegetable products for babies of five, eight, and twelve months and fruit and cereal products of three different brands. The comparison of the composition of the saturated (C18:0, C16:0, C14:0, C12:0, C10:0), the unsaturated monoenoic (C18:1n9 and C16:1n7) and the polyenoic (C18:2n6 and C18:3n3) fatty acids was determined by gas chromatography. All analyzed baby food products provided well‐balanced amounts of saturated fatty acids on the one hand (saturated fatty acids (SFA) 31—37% of total fatty acids) and unsaturated fatty acids on the other hand (monounsaturated fatty acids (MUFA) 23—26% and polyunsaturated fatty acids (PUFA) 38—46% of total fatty acids, respectively). The P/S‐ratio in vegetable products of five months reached a value of 1.5, in all other analyzed products it was around 1. The n‐6:n‐3‐ratio was 10:1 in fruit and cereal products, followed by 11.6:1 in vegetable products of eight and twelve months and 13.5:1 in the group of vegetable products of five months. Since there is a lack of arachidonic acid and docosahexaenoic acid in baby food products, it might be of advantage to consider whether such products should be supplemented by these long‐chain polyunsaturated fatty acids.     

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.     

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.