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71.
72.
ABSTRACT: The purpose of this study was to determine differences in nutrient and energy intakes and in quantity of food eaten, and to compare the knowledge, attitudes, and practices of users of reduced-sugars foods and beverages with those who use only the full sugar versions of the same products. Records for adults (≥ 20 y old) responding to the 1994–1996 Continuing Survey of Food Intakes by Individuals (CSFII) and the Diet Health and Knowledge Survey were used. CSFII food lists were scanned for both full and reduced-sugar versions of yogurt, cocoa, and other milk beverages, frozen and gelatin desserts, puddings, breads, cookies, cakes, fruit drinks, carbonated and noncarbonated drinks, confectionary products, and sweeteners. Recalls were sorted for those reporting use of only full sugar (FS) products and those reporting mixed use of full sugar and reduced-sugar (RS) versions. Comparisons were made between demographic characteristics, body mass index, food group servings, food intake amounts, and nutrient densities. When compared with FS users, RS users consistently reported significantly higher intakes of fruit, lower intakes of discretionary fat and added sugars, and equal or lower intakes of other foods (in gram amounts), except for greater intake of yogurt and frozen and gelatin desserts. RS users tended to report similar or higher micronutrient intakes compared with FS users. After adjusting for energy intake, significantly higher micronutrient intakes were found for both males and females consuming RS foods and beverages (13 and 15 of 17 nutrients, respectively). 相似文献
73.
Aquilanti L Garofalo C Osimani A Silvestri G Vignaroli C Clementi F 《Journal of food protection》2007,70(3):557-565
The transfer via the food chain from animals to humans of microbes that are resistant to antimicrobial agents is of increasing concern. To determine the contributions of nonpathogenic microflora to the occurrence and spread of antibiotic resistance (AR) genes in the food chain, 123 lactic acid bacteria were isolated from 29 samples of raw and processed pork and chicken meat products that had previously tested positive for one or more AR genes that encode clinically relevant ARs: tet(M), tet(O), tet(K), erm(A), erm(B), erm(C), aac (6')-Ie aph (2")-Ia, mecA, and blaZ. All of the isolates were initially tested for their AR gene profiles by PCR. The 59 isolates carrying a tet, erm, or blaZ gene were taken through molecular identification, analyzed by determination of the MIC, and subjected to genetic fingerprinting. Lactococcus garvieae was the predominant species (28 isolates), followed by Lactobacillus plantarum (11 isolates) and L. salivarius (6 isolates), whereas Lactococcus lactis subsp. lactis, Lactobacillus johnsonii, L. reuteri, L. crispatus, and L. brevis were identified at lower frequencies. The tet(M) and erm(B) genes were the most frequently detected. Assessment of multiple resistances in 18 tet positive (tet+) isolates revealed that tet(M) plus erm(B) and tet(K) plus erm(B) were the most frequent AR gene patterns. Partial sequencing of the tet(M) open reading frame of three selected strains showed high sequence similarities (> 99%) with tet(M) genes previously found in human pathogens (Listeria monocytogenes and Neisseria meningitidis). Southern hybridization with plasmid profiles revealed these strains contained tet(M)-carrying plasmids. 相似文献
74.
Gloria A. Smart Marjorie Warrington Dorothy Dellar John C. Sherlock 《Journal of the science of food and agriculture》1983,34(6):627-637
Following earlier work, detailed studies have been carried out on the lead uptake of individual foods from soft and hard water containing various amounts of lead. Experiments have also been made to determine whether solutions of lead nitrate in distilled water simulate the behaviour of water containing naturally present lead. The effect of length of cooking time, weight/volume ratio and salt addition have been studied, as well as the depostion of lead on to cooking vessels. In general, green vegetables, carrots, rice and spaghetti were found to take up more lead than do other foods. The difference in uptake observed between hard and soft waters varied according to the particular food being studied. Uptake from lead nitrate solutions showed a very similar pattern to uptake from hard water containing naturally present lead. Equilibrium was reached after only 5 min cooking for cabbage and spaghetti. Varying the solid/volume ratio for cabbage affected the uptake of lead from water, but the addition of sodium chloride or sodium bicarbonate had little effect on lead uptake. There was no sign of saturation in uptake of lead by cabbage from solutions of 11 mg litre?1 lead as lead nitrate. Deposition of lead occurred on both aluminium and glass saucepans, and cleaning was more effective in removing lead from glass saucepans. Results obtained from the analysis of diets in a small population at Ayr confirmed those obtained previously by laboratory experiments. 相似文献
75.
Gloria Urbano Sławomir Frejnagel Jesús M. Porres Pilar Aranda Elena Gomez-Villalva Juana Frías María López-Jurado 《European Food Research and Technology》2007,226(1-2):105-111
The effect of dephytinization of Pisum sativum, L. flour on the bioavailability of Mg and Zn was evaluated in growing rats. Processing of legume flours under optimal conditions
for phytase activity (pH 5.5, 37 °C, 60 min) and subsequent removal of the soaking solution led to a 42 and 61% reduction
in the content of Mg and Zn, respectively. Treatment with phytase led to an additional reduction in the concentration of the
above-mentioned seed flour components, compared to the raw pea flour (69% and 74% for Mg and Zn, respectively). The considerable
reduction in the content of inositol phosphates with high degree of phosphorylation attained under both processing conditions
did not affect the digestive utilization of Mg, whereas the metabolic utilization of this mineral increased significantly.
The digestive and metabolic utilization of Zn increased significantly in response to both processes assayed, reaching the
highest values in the experimental group that was fed the phytase-treated pea flour diet. The amount of Mg retained by the
experimental animals was reflected in the content of this mineral in the different tissues studied (femur, sternum, kidney,
and heart), whereas no correlation was found in the case of Zn. 相似文献
76.
77.
78.
Antioxidant Activity of Added Phenolic Compounds in Freeze-Dried Microencapsulated Sunflower Oil 总被引:1,自引:0,他引:1
Joaquín Velasco Francisca Holgado Carmen Dobarganes Gloria Márquez-Ruiz 《Journal of the American Oil Chemists' Society》2009,86(5):445-452
This study was aimed at evaluating the effectiveness of phenolic antioxidants with a similar structure but having a different
polarity in dried microencapsulated sunflower oil. The antioxidants tested were, on one hand, α-tocopherol and its water soluble
analogue, Trolox, and on the other, gallic acid and its ester derivatives, propyl gallate and dodecyl gallate. At a moderate
temperature (40 °C), the samples were oxidized under accelerated conditions by using Cu(II) as an oxidation catalyst. The
progress of oxidation was followed up over time in the free and encapsulated oil fractions. The peroxide value, the total
content of polymers and, when appropriate, the content of α-tocopherol were determined. Quantitative analysis of the total
fraction of the non-volatile oxidation products and their distribution in oligomers, dimers and monomers was applied to samples
to obtain a complete evaluation of oxidation. Finally, as a complementary measure, the antioxidants were also assessed by
direct application of the Rancimat test at 100 °C on the dried microencapsulated oil samples. Results showed that the antioxidants
of lower polarity in each series, i.e. tocopherol and dodecyl gallate, were to a great extent the most protective antioxidants.
The results obtained by the Rancimat test were consistent with those found during oxidation at moderate temperature. Furthermore,
the addition of Cu(II) reduced proportionally the oxidative stability index of the dried microencapsulated samples. 相似文献
79.
80.
Magnetic flux leakage (MFL) is the most used technique for pipeline inspection, being applied through the use of instrumented PIGs. The pipe wall is magnetized and when metal loss or other irregularities occur, a larger fraction of the magnetic flux “leaks” outwards from the wall and is detected by sensors. MFL presents some limitations since it requires magnetic saturation of the pipe wall. Therefore, it is difficult to inspect small diameter and thick wall pipelines. Internal corrosion sensor (ICS) has been developed as a solution for internal corrosion measurements of thick walls. The technique, also called “field disturbance”, is based in a direct magnetic response from a small area of the wall. It is not necessary to achieve the magnetic saturation of the pipe material, and thus ICS performance is not affected by the thickness of the pipe wall. In the present work, finite element calculations are performed and the best resultant configuration of the sensor is proposed. Experimental tests with a prototype were carried out and the results give a strong indication of the validity of the theoretical model proposed for sizing. 相似文献