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PubMed1992

[Studies on the analysis of copper chlorophyll and sodium copper chlorophyllin in imported foods].

The analysis of copper chlorophyll (CuCh) and sodium copper chlorophyllin (CuCh-Na) in imported foods was carried out. Standards of CuCh and CuCh-Na were examined by ultraviolet and visible spectrophotometer. CuCh gave absorption maximum around 650 nm, while CuCh-Na gave around 630 nm. Imported sweets and liqueurs were homogenized and extracted with ethyl acetate. These extracts also gave absorption maxima absorbance around 650 nm or 630 nm. The results suggested that a distinction between CuCh and CuCh-Na in foods was possible by spectrophotometry. Visible spectrophotometric quantitation was also tried. However the estimated levels of CuCh or CuCh-Na in the samples by this method did not meet with those by atomic absorption spectrometry.

Chlorophyllides↗
PubMed1995

Food intake and growth in chickens given food in the wet form with and without access to drinking water.

1. Individually caged growing chickens were offered a commercial grower food mixed with 1.5 to 2.25 times the weight of water and the effects, compared to giving the same food in air-dry form, on food intake, body weight gain and carcase composition were investigated. 2. Male broilers (24) were given either a grower food in the air-dry form with access to drinking water or the same food mixed with 2.0 parts of water (700 g water/kg of mixed food) with no drinking water from 28 to 49 d of age. From 49 to 63 d all birds were given dry food and drinking water and were then killed for carcase analysis. Food intake and weight gain were significantly increased during the wet-feeding period, as was carcase protein but not abdominal or carcase fat at the end of the experiment. 3. Five male broilers were given each of 5 dietary treatments containing 0 (control), 1.5, 1.75, 2.0 and 2.25 times added water (640, 673, 700 and 723 g water/kg) from 28 to 49 d. Food intakes, body weight gains and carcase weights were significantly increased for all water additions compared with dry food, but there were no significant differences between different water additions. 4. Female broiler chicks responded to wet feeding (700 g water/kg) in a similar manner to males and the dry matter approximate digestibility was increased from 0.65 for the dry food to 0.73 for the wet. 5. Cockerels of an egg-laying strain did not increase their intake of dietary dry matter when it was fed in the wet form (700 g water/kg), but there was a significant increase in body weight gain. 6. Male broilers were offered wet food (700 g water/kg) with or without access to drinking water. There was equal stimulation of food intake, growth and carcase weight with both wet-feeding treatments. 7. Providing food mixed with sufficient water to give a porridge-like consistency significantly increased weight gains in each of the five experiments and significantly improved food conversion efficiency in three of the five. It is not necessary to withhold drinking water in order to obtain this effect.

Animal Feed↗
PubMed2006

Quality-control materials in the USDA National Food and Nutrient Analysis Program (NFNAP).

The US Department of Agriculture (USDA) Nutrient Data Laboratory (NDL) develops and maintains the USDA National Nutrient Databank System (NDBS). Data are released from the NDBS for scientific and public use through the USDA National Nutrient Database for Standard Reference (SR) ( http://www.ars.usda.gov/ba/bhnrc/ndl ). In 1997 the NDL initiated the National Food and Nutrient Analysis Program (NFNAP) to update and expand its food-composition data. The program included: 1) nationwide probability-based sampling of foods; 2) central processing and archiving of food samples; 3) analysis of food components at commercial, government, and university laboratories; 4) incorporation of new analytical data into the NDBS; and 5) dissemination of these data to the scientific community. A key feature and strength of the NFNAP was a rigorous quality-control program that enabled independent verification of the accuracy and precision of analytical results. Custom-made food-control composites and/or commercially available certified reference materials were sent to the laboratories, blinded, with the samples. Data for these materials were essential to ongoing monitoring of analytical work, to identify and resolve suspected analytical problems, to ensure the accuracy and precision of results for the NFNAP food samples.

Agriculture↗
PubMed2005

Food choices at lunch during the third year of life: high selection of animal and starchy foods but avoidance of vegetables.

AIM: The objective was to show patterns of food selection by 2- to 3-y-old children for a wide variety of foods in a self-service cafeteria and to assess the effect of individual variables (gender, BMI, mode of feeding after birth and rank in sibship). METHODS: In a nursery self-service canteen, food choices at lunch made by children (n=418, 24-36 mo; 109 observations per child on average) were recorded by trained assistants who monitored portion size. An offer of eight dishes (animal products, starchy foods, combination dishes, vegetables and dairy products), excluding dessert-type foods, was proposed. Choice level was calculated for each food. Analysis of variance was used to compare choices for the various foods and to assess the effect of the individual variables. RESULTS: The choice of a food largely depended upon its nature: animal products, starchy foods and their combinations were widely chosen, whereas vegetables were not often selected; the choice for dairy products depended upon the type. The mode of preparation of the food influenced its choice. Segmenting products were identified; however, except for cheeses, a given child did not refuse an entire food category. Children's characteristics did not explain the choice variability. CONCLUSION: At the age of 2 to 3 y, children preferentially choose animal products and starchy foods and avoid vegetables; the high individual variability of their food choices could be related to previous food experiences.

Cheese↗
PubMed1982

The presence of aflatoxin and some polycyclic aromatic hydrocarbons in human foods.

An analysis of several common food items (fish, meat, crops and spices) as sold in the Nigerian markets has shown the presence of (a) benzo[a]-pyrene and benz[a]anthracene in fish and meat samples, and (b) aflatoxin in crops and spices. These results are discussed in relation to the relatively high incidence of cancer in tropical Africa.

Aflatoxins↗
PubMed1975

Iron content of native foods.

Chemical analysis showed that some foods cooked in a cast iron pot gained significantly in iron content. This was particularly so for rice and green vegetables, but not for the major root staples of Papua New Guinea. It therefore seems unlikely that a campaign to encourage the use of iron pots for cooking would significantly increase the iron content of diets in Papua New Guinea to an extent which would mitigate the high prevalence of iron deficiency.

Anemia, Hypochromic↗
PubMed1992

[Use of polychlorinated biphenyl congener analysis for monitoring food and raw material of animal origin].

Occurrence of individual polychlorinated biphenyl (PCB) congeners in the environment, foodstuffs and other biological materials was assessed. Analysis of specific PCB congeners (28, 52, 101, 138, 153, 180), occurring in animal raw materials and foodstuffs most frequently, has been implemented. Sample processing, isolation of fat from milk, meat, organs, fat tissue and eggs, and separation of PCB from fats using the sorbents Florisil or Ekosorb (a new Czechoslovak sorbent based on modified silica gel, Kavalier Glassworks, Votice) are described in detail. Individual PCB congeners were determined by capillary gas chromatography (gas chromatograph Varian VISTA 6,000, equipped with a 63Ni ECD; silica capillary column SPB-5, 30 m x 0.32 mm I.D., 0.25 micron film; column temperature programme: 60 degrees C for 2 min, then to 250 degrees C at 20 degrees C/min and held for 13 min; splitless injection). Chromatograms of commercial chemicals Delor 103 and Delor 106 (corresponding to Aroclor 1242 and 1260, respectively), of a mixture of six specific PCB congener standards and of a PCB--containing milk sample are presented in Fig. 1-3. Methods of PCBs estimation, currently used in Czechoslovakia, and benefits of congeneric analysis of PCBs (reproducibility of results, quantification of individual congeners) are discussed. Analysis of specific PCB congeners is used for the assay of PCBs in foodstuffs and investigations of PCBs dynamics in food chains and distribution and accumulation of PCBs in animal organisms. Contents of specific PCB congeners in milk, pork and pig liver and kidney samples are given in Tab. II.(ABSTRACT TRUNCATED AT 250 WORDS)

Dairy Products↗
PubMed2003

Risk analysis applied to food fortification.

OBJECTIVE: To describe how a risk analysis can be applied to food fortification, with emphasis on voluntary fortification and intake levels that might exceed usual dietary levels. DESIGN: Use of the risk analysis model as a frame to classify nutrients according to the risk of exceeding upper safe intake levels. Furthermore, to apply the model when discussing possible consequences of liberal fortification practices on eating behaviour and disease patterns. SETTING: The discussion on food fortification presently going on internationally. RESULTS: Micronutrients can be classified according to their safety margin, i.e. the size of the interval between the recommended intake and the upper safe level of intake. We suggest that nutrients with a small safety margin, i.e. for which the upper safe level is less than five times the recommended intake, be placed in a category A and should be handled with care (retinol, vitamin D, niacin, folate and all minerals). Category B comprises nutrients with an intermediate safety margin (vitamins E, B6, B12 and C), while nutrients that according to present knowledge are harmless even at 100 times the recommendation (vitamin K, thiamin, riboflavin, pantothenic acid and biotin) are categorised as C. DISCUSSION: The risk analysis model is a useful tool when assessing the risk of both too low and excess intakes of single micronutrients, but can also be applied to analyse the consequences of fortification practices on eating behaviour and disease patterns. Liberal fortification regulations may, for example, distort the conception of what is healthy food, and drive consumption towards a more unhealthy diet, contributing to the plague of overweight and concomitant increased risk of degenerative diseases. CONCLUSION: The impact of fortification practices on the total eating pattern of a population should become an integrated part of the discussions and regulations connected to the issue.

Food, Fortified↗
PubMed2003

Validation and cross-national comparison of the food neophobia scale (FNS) using confirmatory factor analysis.

The food neophobia scale [FNS; Appetite 19 (1992) 105] has been used to assess willingness to try new foods in studies conducted around the world. Although it is tempting to compare FNS scores across these studies, appropriate psychometric analyses are required to validate the scale and allow cross-cultural comparisons. These analyses were pursued in the current study using confirmatory factor analysis in conjunction with a data analysis strategy described by Steenkamp and Baumgartner [J. Consumer Res. 25 (1998) 78] and random, representative samples drawn from the United States, Sweden and Finland. A unidimensional scale was constructed using eight of the original 10 items from the FNS, and this model provided an excellent fit to the data from the US and Swedish samples. An acceptable fit was achieved for six items when data from the US, Sweden and Finland were used. Based on these analyses, we recommend that two items from the original FNS be dropped (items 5 and 9). Elimination of additional items may be premature given the potential contributions of difference in sampling and testing methodology associated with data collection from the three samples. Future efforts to develop a FNS for cross-national comparisons should target the development of a scale with 14-16 items so that dropping several items from a model (due to translation or other problems) allows retention of a sufficient number of items to insure a robust test. However, even with only six items, our results supported the conclusion that people from Sweden are generally more willing to try novel foods as compared to people from the US and Finland. Future studies should focus on the source of this enhanced willingness to try novel foods among the Swedes and the potential use of this information in the development of programs aimed at facilitating dietary change.

Adolescent↗
PubMed2004

Effects of several variable factors on the isotope ratio by HRGC-MS.

In the isotope ratio (Ir) analysis using GC-MS, several variable factors in sampling incidental to any food analysis were investigated for yuzu fruit. The Irs of ten monoterpene hydrocarbons in yuzu essential oils from each of six fruiting positions of three trees were measured. The sign test following t-test of all the Ir values demonstrated that there was no significant difference between both sampling years of 2001 and 2002. There was also no significant variation in the Ir values among the three trees and six fruiting positions in the individual two years.

Citrus↗
PubMedDate not supplied

The Horwitz ratio (HorRat): A useful index of method performance with respect to precision.

The Horwitz ratio (HorRat) is a normalized performance parameter indicating the acceptability of methods of analysis with respect to among-laboratory precision (reproducibility). It is the ratio of the observed relative standard deviation among laboratories calculated from the actual performance data, RSDR (%), to the corresponding predicted relative standard deviation calculated from the Horwitz equation PRSDR (%) = 2C(-0.15), where C is the concentration found or added, expressed as a mass fraction. It is more or less independent of analyte, matrix, method, and time of publication (as a surrogate for the state of the art of analytical chemistry). It is now one of the acceptability criteria for many of the recently adopted chemical methods of analysis of AOAC INTERNATIONAL, the European Union, and other European organizations dealing with food analysis (e.g., European Committee for Standardization and Nordic Analytical Committee). The origin and applications of the formula are described. Consistent deviations from the ratio on the low side (values <0.5) may indicate unreported averaging or excellent training and experience; consistent deviations on the high side (values >2) may indicate inhomogeneity of the test samples, need for further method optimization or training, operating below the limit of determination, or an unsatisfactory method.

Chemistry Techniques, Analytical↗
PubMed2005

Neuron activity in the anterolateral motor cortex in operant food-acquiring and alcohol-acquiring behavior.

The interactions of the neuronal mechanisms of food-acquiring behavior and newly formed operant alcohol-acquiring behavior were studied by recording the activity of individual neurons in the anterolateral area of the motor cortex in chronically alcoholized rabbits. Adult animals learned food-acquiring behavior in a cage with two feeders and two pedals, in the comers (the food in the feeders was presented after pressing the corresponding pedal). After nine months of chronic alcoholization, the same rabbits learned an alcohol-acquiring behavior in the same experimental cage (gelatin capsules filled with 15% ethanol solution were placed in the feeders instead of food). Analysis of neuron activity showed that the set of neurons involved in supporting food-acquiring and alcohol-acquiring behaviors overlapped, though not completely. These experiments not only help us understand the neuronal mechanisms of the newly formed and the previously formed behaviors, but also facilitate the development of concepts of the similarity of the neuronal mechanisms of long-term memory and long-term modifications of the nervous system, occurring in conditions of repeated intake of addictive substances.

Action Potentials↗
PubMed1999

Analysis of anthocyanins in red wine and fruit juice using MALDI-MS.

Matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) is a powerful new technique that will have a great impact on food analysis. This study is the first to demonstrate the applicability of MALDI-MS to perform both qualitative and quantitative analyses of anthocyanins in food. 2,4, 6-Trihydroxyacetophenone (THAP) was found to be a good matrix for analysis of anthocyanins, with the best spot-to-spot repeatability. After a simple sample preparation, the presence of anthocyanins as cations with molecular masses was found in ratios expected from their fruit sources. Quantification of anthocyanins should be possible by choosing appropriate internal standards. MALDI-MS responses were linear, groups of chemically similar anthocyanins had similar responses, and addition of an internal standard had no effect on relative responses of the other anthocyanins.

Anthocyanins↗
PubMed1997

Impact of gender, ethnicity, meal component, and time interval between eating and reporting on accuracy of fourth-graders' self-reports of school lunch.

OBJECTIVE: To validate fourth-graders' self-reports of school lunch by comparing their reports to lunch observations, and to determine the impact on accuracy of gender, ethnicity, meal component, and time interval between eating and reporting. DESIGN: Students were randomly selected, observed eating lunch, and interviewed the same day, next day, or Monday regarding Friday's lunch. Accuracy of reporting items was determined by tallying matched foods (items reported and observed), phantom foods (items reported but not observed), and omitted foods (items not reported but observed). Accuracy of reporting amount eaten was determined by calculating absolute and arithmetic differences. SUBJECTS: Subjects were 260 students: 89 same-day, 148 next-day, and 23 Monday recalls; 59 whites (30 boys) and 201 blacks (103 boys) from four schools. STATISTICAL ANALYSES: Rates for matched, phantom, and omitted foods; analysis of variance; Friedman's nonparametric analog of analysis of variance; Student-Newman-Keuls' post hoc comparisons. RESULTS: In regard to reporting items, the respective rates for matched, phantom, and omitted foods were 84%, 5%, and 16% for same-day recalls; 68%, 13%, and 32% for next-day recalls; and 38%, 48%, and 62% for Monday recalls. Rates for omitted and phantom foods were higher for Monday recalls than for next-day recalls, which were higher than for same-day recalls (P < .05 for all). In regard to reporting amounts, analysis by gender, ethnicity, and time interval failed to yield significant main or interaction effects. When children correctly reported items eaten, they were quite accurate in reporting amounts eaten. Omitted food rates were lowest for beverage, followed by entree, and highest for miscellaneous and condiment. APPLICATIONS: Even under the best conditions (ie, reporting within 90 minutes after eating school lunch), children have difficulty accurately reporting what they have eaten. As the time interval between eating and reporting increases, accuracy decreases markedly. Techniques that improve reporting of items eaten should result in improved accuracy of reporting amounts eaten.

Analysis of Variance↗
PubMedDate not supplied

Desire to eat high- and low-fat foods following a low-fat dietary intervention.

OBJECTIVE: This study examined changes in desires to eat high-fat and low-fat foods across an obesity treatment program. The hypotheses under examination were (1) preferences for low-fat foods would increase across time and (2) preferences for high-fat foods would decrease across time. DESIGN: Single-group, prospective examination of desires to eat 48 foods, categorized according to fat content, before and after the 16-week treatment program. SETTING: University clinic, Memphis, Tennessee. PARTICIPANTS: 118 obese (mean weight = 194.4 lbs) women (mean age = 45.24 years) participating in an obesity treatment program. INTERVENTION: A 16-week cognitive-behavioral program for obesity. VARIABLES MEASURED: Desires to eat 48 foods varying in fat content and whether or not participants actually ate these foods. ANALYSIS: Analysis of variance, multiple regression, and paired t tests. RESULTS: The results indicate that during the program, preferences for low-fat foods increased, whereas preferences for high-fat foods decreased. These changes mirrored the changes in consumption of both low-fat and high-fat foods. CONCLUSIONS AND IMPLICATIONS: Within a behavioral economic perspective, the reinforcement value of low-fat foods may increase following a low-fat dietary intervention, whereas the reinforcing properties of high-fat foods may decline. This is desirable as low-fat foods hold many advantages over high-fat foods in terms of weight maintenance.

Adult↗