Food consumption patterns in an adult urban population in Beirut, Lebanon

OBJECTIVES: To investigate, measure and assess the food consumption pattern of the adult population living in Beirut, Lebanon, and to identify inadequate or excessive intake of food groups particularly linked to non-communicable diseases. DESIGN: A cross-sectional food consumption survey was conducted in 2001. Dietary habits were assessed by means of a quantitative food-frequency questionnaire. SETTING: Dietary survey of the urban population (Beirut). SUBJECTS: Random sample of 444 adult subjects (aged 25-54 years) in Beirut. RESULTS: The mean consumption of food by the study population was estimated to be 3,030 g day(-1), providing an energy intake of 2,523.57 kcal day(-1). Fat contributed 38.9% to the average daily energy intake, protein 13.4% and carbohydrates 47.2%. Mean consumption of fruits and vegetables was approximately 367 g day(-1) and 45.3% of subjects consumed less than the recommended 400 g daily. Cereals contributed 324.5 g day(-1), providing 35.0% of daily energy intake, with bread being the most highly consumed (146.2 g day(-1)) in this food group. The mean intake of meat and poultry products was 91.7 g day(-1) and provided 8.8% of daily energy intake, with consumption of butchery products especially beef being the highest (47.6 g day(-1)) followed by poultry (36.1 g day(-1)). A low consumption of fish was noted (19.7 g day(-1)), with 73.6% of subjects consuming less than the recommended 2 servings of fish per week. Dairy products contributed 243.1 g day(-1) or 10.9% of daily energy intake, and milk was the least consumed dairy product (56.8% of consumers). The intake of added fats and oils, excluding those in cooked recipes, was 20.4 g day(-1); olive oil was not used in cooking but was added solely at the table and its mean intake was 5 g day(-1). The consumption of butter was low (0.86 g day(-1)) and vegetable oil was the type of fat mostly used in cooking. The average intake of alcoholic beverages was low (33.6 g day(-1)), accounting for 0.7% of total energy intake. Women had significantly higher intakes of milk, dairy products, vegetables and coffee than men (P < 0.05). The percentage of women who reported the use of low-fat items was significantly higher than that of men. Younger people (25-34 years) ate significantly more meat, sugar, alcoholic beverages and soft drinks, and consumed significantly less cooked vegetables and legumes, than older ones (P < 0.05). CONCLUSIONS: The rather high contribution of fat to daily energy intake, the low intake of fish and the relatively high percentage of people consuming less than the recommended amount of fruits and vegetables observed in this study suggest that the adult Lebanese population is at increased risk of cardiovascular diseases, obesity and other non-communicable diseases, which provides the basis for recommending increased intakes of fish, particularly fatty fish, and fruits and vegetables.     

Use of Aloe vera gel coating preserves the functional properties of table grapes

Table grapes (Vitis vinifera L. cv. Crimson Seedless) were coated with Aloe vera gel according to our developed patent (SP Patent P200302937) and then stored for 35 days at 1 degrees C, and the subsequent shelf life (SL) was monitored at 20 degrees C. Uncoated clusters showed a rapid loss of functional compounds, such as total phenolics and ascorbic acid. These changes were accompanied by reduction of the total antioxidant activity (TAA) and increases in total anthocyanins, showing an accelerated ripening process. On the contrary, table grapes coated with Aloe vera gel significantly delayed the above changes, such as the retention of ascorbic acid during cold storage or SL. Consequently, Aloe vera gel coating, a simple and noncontaminating treatment, maintained the functional properties during postharvest storage of table grapes.     

Purification of xylitol obtained by fermentation of corncob hydrolysates

Hydrolysates obtained by autohydrolysis-posthydrolysis of corncobs were detoxified with charcoal, concentrated, supplemented with nutrients, and fermented with Debaryomyces hansenii. After biomass removal, the fermented media contained 0.1137 kg of nonvolatile components (NVC)/kg of liquor, which corresponded mainly to xylitol (0.6249 kg/kg of NVC) but also to minor amounts of inorganic components (measured as ashes), proteins, nonfermented sugars (xylose and arabinose), uronic acids, arabitol, and other nonvolatile components (ONVC). The media were subjected to further processing (sequential stages of adsorption, concentration, ethanol precipitation, concentration, and crystallization) to obtain food-grade xylitol. Adsorption experiments were carried out at various solid-to-liquor ratios. Under selected conditions (1 kg of charcoal/15 kg of liquors), the xylitol content increased to 0.6873 kg/kg of NVC, and almost total decoloration was achieved. The resulting liquor was concentrated by evaporation to increase its NVC content to 0.4032 kg/kg of liquor (corresponding to a xylitol concentration of 0.280 kg/kg of liquor), and ethanol was added to precipitate a part of the NVC (mainly proteins, but also uronic acids, ashes, and other nonvolatile compounds). Refined liquors (containing 0.7303 kg of xylitol/kg of NVC) were concentrated again, and ethanol was added (to reach 40-60% volume of the stream) to allow crystallization at -10 or -5 degrees C. Under selected conditions, 43.7% of xylitol contained in the initial fermentation broth was recovered in well-formed, homogeneous crystals, in which xylitol accounted for 98.9% of the total oven-dry weight. Material balances are presented for the whole processing scheme considered in this work.     

Time-resolved spectral studies of blue-green fluorescence of artichoke (Cynara cardunculus L. Var. Scolymus) leaves: identification of chlorogenic acid as one of the major fluorophores and age-mediated changes

Synchrotron radiation and the time-correlated single-photon counting technique were used to investigate the spectral and time-resolved characteristics of blue-green fluorescence (BGF) of artichoke leaves. Leaves emitted BGF under ultraviolet (UV) excitation; the abaxial side was much more fluorescent than the adaxial side, and in both cases, the youngest leaves were much more fluorescent than the oldest ones. The BGF of artichoke leaves was dominated by the presence of hydroxycinnamic acids. A decrease in the percentage of BGF attributable to the very short kinetic component (from 42 to 20%), in the shape of the BGF excitation spectra, and chlorogenic acid concentrations indicate that there is a loss of hydroxycinnamic acid with leaf age. Studies on excitation, emission, and synchronized fluorescence spectra of leaves and trichomes and chlorogenic acid contents indicate that chlorogenic acid is one of the main blue-green fluorophores in artichoke leaves. Results of the present study indicate that 20-42% (i.e., the very short kinetic component) of the overall BGF is emitted by chlorogenic acid. Time-resolved BGF measurements could be a means to extract information on chlorogenic acid fluorescence from the overall leaf BGF.     

Comparative study of health properties and nutritional value of durian, mangosteen, and snake fruit: experiments in vitro and in vivo

In vitro and in vivo studies of the health and nutritional properties of durian (Durio zibethinus Murr.) were compared with snake fruit (Salacca edulis Reinw.) and mangosteen (Garcinia mangostana). Dietary fibers, minerals, and trace metals were comparable. Total polyphenols (mg of GAE/100 g of FW) and flavonoids (85.1+/-6.1) were significantly higher (p<0.05) than in snake fruit (217.1+/-13.2 (mg of CE/100 g of FW)), durian (309.7+/-19.3 and 61.2+/-4.9), and mangosteen (190.3+/-12.1 and 54.1+/-3.8). Antioxidant activity (microM TE/100 g of FW) of durian measured by DPPH and ABTS assays (228.2+/-13.4 and 2016.3+/-81.1) was significantly higher (p<0.05) than in snake fruit (110.4+/-7.9 and 1507.5+/-70.1) and mangosteen (79.1+/-5.9 and 1268.6+/-62.3). HPLC/DAD analysis of durian (microg/100 g of FW) showed that quercetin (1214.23+/-116.7) was present at levels three times that of caffeic acid, and twice as high as p-coumaric and cinnamic acids. The correlation coefficients between the bioactive compounds of fruits and their antioxidant activities were high (R2=0.99). Male Wistar rats (25) were divided into five dietary groups: the control group was fed the basal diet (BD); in addition to BD, the cholesterol (Chol) group was supplemented with 1% of Chol; the diets of the Chol/Durian, Chol/Snake, and Chol/Mangosteen groups were supplemanted with 5% of these fruits, respectively. It was found that diets supplemented with durian, and to a lesser degree with snake fruit and mangosteen, significantly hindered the rise in plasma lipids and the decrease in antioxidant activity. The nutritional values were comparably high. In conclusion, it could be suggested that inclusion of studied tropical fruits, especially durian, in known disease-preventing diets could be beneficial.     

Effect of fruiting body maturity stage on chemical composition and antimicrobial activity of Lactarius sp. mushrooms

The effects of fruiting body maturity on chemical composition and antimicrobial activity of the wild mushrooms, Lactarius deliciosus and Lactarius piperatus, were evaluated. Immature and mature samples were analyzed for proximate constituents (moisture, fat, crude protein, ash, carbohydrates), nutritional value, and individual composition in fatty acids and sugars. Protein content, MUFA (monounsaturated fatty acids), and PUFA (polyunsaturated fatty acids) percentages increased with the fruiting body maturity stage, while carbohydrate and SFA (saturated fatty acids) content decreased. The maturity stage did not significantly affect the individual sugar profile. The antimicrobial activity of the mushrooms was screened against Gram positive and Gram negative bacteria and fungi, and correlated to the amounts of phenols, flavonoids, ascorbic acid, beta-carotene, and lycopene present in the immature and mature fruiting bodies. Mature fruiting bodies with mature spores presented lower antimicrobial activity, which was in agreement with the bioactive compound content found in those samples.     

Sedimentary characterization of Tagus estuarine beaches (Portugal)

Background, Aim and Scope  The distribution of sediments in estuarine beaches is controlled by the interactions between sediment supply, hydrodynamic processes and human intervention. The main purpose of this study is to characterize the sediments of Tagus estuarine beaches in order to understand their origin and to contribute to a better knowledge of the Tagus estuary sediment budget. Methods  Surface sediment samples were collected across beach profiles and sand grain size analysis was performed by dry sieving. Grain size statistics for the median (d₅₀) and standard deviation (SDM) were obtained using the Moment method. This study was complemented by a qualitative evaluation of the sediment composition. Cross-shore topographic surveys were conducted for selected sampling sites. Results  Tagus estuarine beach sediments are mainly composed of quartz sand particles which are fine-grained and well sorted near the mouth of the estuary and medium to coarse-grained and moderately sorted in the inner domain. Compositional results show evidence of active anthropogenic sediment sources, especially in the coarser fractions. Discussion  The analysis of the textural and compositional characteristics of beach sediments in the inner estuarine domain is compatible with local sedimentary sources, while a marine signature is present at the mouth and inlet channel sediments. In the inner domain, differences in the sedimentary processes are represented by the textural characteristics of the sediments, such as the sorting degree and the gravel content. Sediment characteristics also reflect human intervention in the system, with the introduction of anthropogenic and allochthonous particles and the mixture of sediments from different sources. Conclusions  The sediments of the inner Tagus estuarine beaches are derived from local Plio-Pleistocene outcrops while inlet and outer estuary beaches reveal a dominant marine source. Beach textural variability observed in the inner domain is not related to wave forcing gradients, but mainly to variations in the sedimentary processes along the estuarine margins and to human intervention. Results show that the Tagus estuarine beaches depended, almost exclusively, on sediment input from local sources until the last century. With increasing human occupation, sediment transfers became dominated by anthropogenically related activities mainly connected with the occupation of estuarine margins and dredging. Recommendations and Perspectives  Further studies should extend the present level of knowledge in what concerns sand transport patterns through additional compositional and geochemical analysis, and the development of new techniques in order to allow the quantitative evaluation of the impact of human activities on the sediment budget.     

有机质肥料中硝酸態氮素分析方法的研究

一、绪言硝酸态氮素定量分析,普通多使用还原法与比色法两种。但有机质肥料如厩肥、堆肥含大量有色体、尿素、氯化物等杂质,以上两种方法,都不适用。动物粪便中,每含有大量铵盐及易于分解的各程氮的化合物。无论在酸性或     

1-methylcyclopropene increases storability and shelf life in climacteric and nonclimacteric plums

The effect of 1-methylcyclopropene (1-MCP) at three different doses (0.25, 0.50, and 0.75 microL L(-1)) on the ripening processes of a climacteric, cv. Santa Rosa, and a suppressed climacteric type, cv. Golden Japan, plum was studied. For both cultivars, positive effects were observed in terms of inhibition of ethylene production and delays of the physical, chemical, and biochemical changes associated with ripening. 1-MCP-treated plums were firmer with lower weight loss, reduced degrees Brix/titratable acidity ratios, and lower color changes during cold storage and subsequent shelf life at 20 degrees C than controls. For most factors, the effectiveness of 1-MCP was dose-dependent in Santa Rosa but dose-independent for Golden Japan.     

Analysis of virgin olive oil volatiles by a novel electronic nose based on a miniaturized SAW sensor array coupled with SPME enhanced headspace enrichment

A novel electronic nose based on solid-phase microextraction (SPME) coupled with a surface acoustic wave (SAW) sensor array has been used to analyze different quality virgin olive oils. A mathematical model was designed with 37 samples to distinguish lampante from the other virgin olive oils categories (extra-virgin and virgin), because lampante-virgin olive oils cannot be consumed without a previous refining process. The model, successfully validated with a test set of 16 samples, was able to classify 90% of the samples correctly. Misclassifications were explained by SPME-HRGC analyses and a second sensory evaluation.