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Résultats 411-420 de 1,442
EFFECT OF SOME PRESERVATION PROCESSES ON THE PHYTOCHEMICAL COMPOUNDS WITH ANTIOXIDANT ACTIVITIES OF BROCCOLI
2009
Walaa El-Shalakany | M Shatlah | M Atteia | Faten, B. EL-Kasas | Soher, S. Mostafa | G.A . Abd EL-Malak
s of broccoli using steam or immersion in hot water as traditional technology and storage conditions by either canning or freezing on the content of compounds with antioxidant properties, i.e. vitamin C, carotenoids, chlorophyll, polyphenol and flavonoid compounds parameters was investigated. Results show that the content of carotenoids was 11.41µg/g while the content of chlorophyll A and chlorophyll B was 30.66 and 9.79µg/g, respectively. The content of both carotenoids and total chlorophyll were decreased after being treated prior to different period storage for 3 and 6 month. Fresh broccoli had 40.45µg/g total chlorophyll this content decreased more significantly for the control (fresh broccoli) than for treated and different storage samples. The content of vitamin C was 124.24 mg/100g. Frozen broccoli after blanching by steam and immersion in hot water at 0 times decreased the percent of ascorbic to 83.85 and 75.89%, respectively. Jarred and canned broccoli with dill, coriander and parsley additives showed decrease in ascorbic acid to 45.98 and 40.55% meanwhile, jarred and canned broccoli without additives decreased ascorbic acid to 43.34 and 39.01%, respectively. Total polyphenols and flavonoids were 276.82 and 7.64 mg/100g on fresh weight. These contents were decreased after processing and different storage conditions. The present of antioxidant activity in fresh broccoli was 75.50%. The degradation of antioxidant activity was increased after 6 month period. The highest degradation observed with canned broccoli without additive while the lowest degradation showed with frozen broccoli blanched by steam which the percents of total antioxidant activities were14.84 and 29.65 %, respectively. The content of ferrous and zinc was 6.4 and 3.9 mg/100g on dry weight. Ferrous increased to 7.0 and 8.4 mg/100g with Jarred with dill, coriander and parsley additives and storage for 3 and 6 month broccoli and to 9.3 and 8.7 mg/100g with canned broccoli with dill, coriander and parsley additives.
Afficher plus [+] Moins [-]PHYSICAL, CHEMICAL AND SENSORY CHARACTERISTICS OF VEGAN CAKE
2009
Salwa, M. Abo-El-Fetoh
The objectives of this research were to investigate physical, chemical and sensory quality attributes and their relation of newly formulated vegan cake. Tiger nut milk (TNM) and alginate-lecithin gel (ALG) were used as the replacement of buffalo, s milk and whole egg at the levels of 50 and 100 %, respectively, in addition to, 50 % mixture (50 % TNM and 50 % ALG) and 100 % mixture (100 % TNM and 100 % ALG) . The results revealed that the lactose content of buffalo, s milk was 5.56%, while, TNM was free lactose. TNM is a good source of many elements as buffalo, s milk such as K, P, Ca, Na and Mg. Whole egg had significantly higher foam capacity than the alginate-lecithin gel . In contrast, alginate-lecithin gel exhibited higher foam stability than whole egg. The foam volume of alginate-lecithin gel characterized with stability during 60 min under testing as compared with whole egg that collapsed after 20 min. Concerning emulsifying activity index (EAI), both ALG and whole egg not showed significant difference (p>0.05). Emulsifying stability index (ESI) of alginate-lecithin gel was stable during 60 min under testing as compared with the whole egg that was stable till 40 min. The presence of replacement increased the batter viscosity at ambient temperature over the control value from 19.65 to 21.71-44.54 poise. Among different replacement, 100 % mixtures showed the highest batter viscosity of 44.54 p followed by 100% ALG (38.72 p), 50% ALG (34.29 p) and 50% mixtures (31.03 p). Control batter had a specific gravity of 0.892 g/cc, whereas batter replacing with 50% ALG, 100% ALG, 50% mixtures and 100 % mixtures had a batter specific gravity of 0.992, 1.009, 1.013 and 1.047 g/cc, respectively. The protein and fat contents of control samples were higher (10.42% and 26.63 %, respectively) than vegan cake samples replaced with TNM and ALG. The total carbohydrate content increased with increasing the replacement levels of TNM and ALG in vegan cake. High staling values (high freshness) of vegan cake samples reached 336.59 % and 334.08 % with vegan cake containing 100 % mixtures and 100 % ALG, respectively, in comparison to the staling of control (299.19 %) at zero time. The lower reduction in staling value was achieved in vegan cake prepared 100 % mixtures and 100 % ALG, since the staling value reduced by 10.29 % and 12.41 %, respectively, in comparison to 15.68 % for control sample after 21 days of storage at room temperature. High stability in specific volume during storage was achieved in the presence of 100 % ALG and 100 % mixture since, the specific volume was reduced by only 7.88 % and 8.83 %, respectively, in comparison to 25.99 % for control sample. The presence of ALG and mixtures decreased the hardness value from 79.46 to 36.28 and 66.11 Newton, indicating improvement in the texture of cake. Cakes containing ALG and mixtures showed lower decrement in moisture content and lower increment in hardness during storage at room temperature. Cake samples prepared with different levels of ALG and mixtures were better quality and showed significantly superior sensory properties scores than cake samples prepared with different levels of TNM which coincided with control sample at zero time. Vegan cake samples stored gave higher values and were be desirable till the end of storage period. Therefore, vegan cake could be successfully made from tiger nut milk and alginate-lecithin gel as the fully replacement of buffalos, milk and whole egg, respectively. In addition to, increase freshness, specific volume and storage at room temperature for 21 days.
Afficher plus [+] Moins [-]CHEMICAL COMPOSITION OF CAMEL'S COLOSTRUM AND MILK IN UNITED ARAB EMIRATES
2008
Rea H. Omer | A.H Eltinay
The chemical composition of 350 samples from camel's colostrum and milk in United Arab Emirates were studied. Results of colostrum showed 6.19 for pH, 1.041g/ml for density, 3.1% for fat, 4.95% for protein, 4.4% for lactose, 12.88% for total solids, 10.55% for non fat total solids, 1.11% for ash, 87% for moisture .For ma-ture milk, data were 6.6 for pH, 0.133% for acidi-ty, 1.028g/ml for density, 3.2% for fat, 2.4% for protein, 4.6% for lactose, 11% for total solids, 7.88% for non-fat total solids, 0.88% for ash, and 88.9% for moisture. The minerals contents in camel colostrum were (mg/100mg) as follows: 103 for calcium, 15.4 for magnesium, 14.0 for sodium, 128 for potassium, 0.25 for iron, 0.17 for copper and 43.4 for inorganic phosphate. Elements in mature camel milk were (mg/100mg) as fol-lows: 74.67 for calcium, 3.4 for magnesium, 42.36 for sodium, 136.64 for potassium, 0.18 for iron, 0.04 for copper, 0.02 for manganese, 0.3 for zinc and 38.4 for phosphorus.
Afficher plus [+] Moins [-]USE OF ESSENTIAL OILS FOR CONTROLLING BACTERIAL ANGULAR LEAF SPOT DISEASE OF CUCUMBER
2008
Gomah A A
Activity of commercially and purified essential oils of aloes, anise, black cumin, caraway, carna-tion, cumin, fennel, garlic, jojoba, lavender, onion, rue and thyme were tested against growth of Pseudomonas syringae pv. lachrymans, caused bacterial angular leaf spot disease of cucumber, in vitro and in vivo. Three essential oils had an inhib-itory effect, based on the determination of the min-imum inhibitory concentrations (MICs 0.25-2.0%). Carnation, fennel and thyme were inhibito-ry at MIC 0.5%. The three mentioned oils showed considerable variation in the inhibitory effect by the disk diffusion method, though the recognized similarity in fumigation treatments. The greatest activity was recorded with thyme (18mm) followed by carnation (15 mm) while fennel showed the low-est effect (9mm). Soaking cucumber seeds of differ-ent cultivars in 2% emulsified oils for a period rang-ing from 0.25 to 4 hours significantly decreased the percentage of germination. Shorter duration of seed soaking, 0.25 to 0.5 hours, showed lower deleterious effect on germination and fennel oil showed greater harmful effect. In greenhouse experiments, the three oils significantly controlled the disease incidence compared to the check treatment, being more pro-nounced for thyme oil followed by fennel and carna-tion oils. Analysis of the essential oils in concern showed eugenol, dieugenol, linolenic acid, methyl chavicol (estragol), anisole and thymol, as an active ingredients.
Afficher plus [+] Moins [-]PRODUCTION OF MICROBIAL CELLULOSE BY TEA FUNGUS "KOMBUCHA"
2007
Sheh ata | Sawsan F | Hussein Ali
In seeking economic production of microbial cellulose, the available and low cost commercial kombucha starter, contains mainly Acetobacter xylinum and Saccharomyces sp., were used under static condition. The best medium composition was black tea extract (1.0 g /100 ml H2O), sucrose (20%) and corn steep liquor, CSL (1%) at 26-28oC for 10 days. The cellulose yield (1.3 g /100 ml) and productive rate (1.3 X 10-3 g / day /ml) were higher than some reported values. Addition of folic acid or its building block p-aminobenzoic acid at additive concentrations 0.20% led to dou-bling the yield (2.37 and 2.43 g / 100 ml culture respectively) and the productive rate (2.37 X 10-3 and 2.43 X 10-3 g / day / ml respectively). Scan-ning electron micrograph showed the structure of the produced microbial cellulose fibrils without any microbial flora after treatment with 1% NaOH.
Afficher plus [+] Moins [-]DEVELOPMENT OF VOLATILE COMPOUNDS OF AVOCADO AND CASIMIROA DURING FRUIT MATURATION
2007
Magda Abd El-Mageed
Avocado fruits (Persea americana Mill) cv. Fuerte and white sapote (Casimiroa edulis) cv. Rotaceae cultivated in Egypt were collected at different maturity stages:green mature,commercial ripe and over ripe stages. The headspace volatiles of each maturity stage was isolated and subjected to gas chromatography- mass spectrometric analy-sis. A total of 43 components were identified in avocado aroma including; terpenes (15), esters (8), aldehydes (8), alcohols (6), ketones (2), thiazoles (l), pyridines (1), toluene and acetic acid, where as 18 compounds were, identified in casimiroa aro-ma, they contained (4) esters, (6) alcohols, (4) aldehydes, (3) terpenes and (1) ketone. Ethanol (Z)-3- hexenol and (E)-2- hexenal were the major constituents in green and ripe fruits of avocado whereas they decreased at the final stage of matu-ration. Over ripe avocado fruits had the highest content of esters (ethyl ethanoate, ethyl acetate and methyl propanoate) and terpenoides especially d-limonene and z-nerolidol. Esters and alcohols comprised more than 85% of the total concentra-tion of volatiles in casimiroa fruits during three stages of maturation. The highest content of ethyl butanoate (sweet and fruity aroma) and ethanol revealed the most prominent effect on consumer acceptability of the cosimiroa flavour attributes. It is obvious that maturation of the fruits was associ-ated with remarkable changes in the volatiles that mainly affect their flavour.
Afficher plus [+] Moins [-]EFFECT OF GROWTH TECHNIQUES (PRUNING METHOD) ON THE PRODUCTION OF CUCUMBER GROWN IN GREENHOUSES
2007
AL-Obeid, S. S.
The present study was carried out to investi-gate the effect of pruning method on growth and production of cucumber (hybrid Aula) grown in greenhouses for 2004 and 2005 growing seasons. Three types of pruning were used : system of prin-cipal stem, system of secondary branchs, and mixed system (principal stem + secondary branchs). The results show the following points * Effect of mixed system is distinguish on early and total production in comparison with the other used methods which present a comparable production. * Failing growth and production of mixed system at the end of season compared with two other used methods. This experience allows to suggest * Use of mixed system necessitate the regular pruning of plants for avoid the physiological fail and the bad morphological and physiologi-cal characteristics of fruits. * Possibility of application the system of principal stem and avoid the system of secondary branchs with the necessity of knowledge the type of branch of varieties for avoid the tardy production
Afficher plus [+] Moins [-]EFFECT OF ETHYL SALICYLIC ACID VAPOUR ON SPROUTING AND ROTS INCIDENCE OF POTATO TUBERS UNDER LONG-TERM STORAGE(a)
2007
Mostafa M | E. Gado
The effect of exposing of potato tubers cv. Di-amond to ethyl salicylic acid (ES) vapour for dif-ferent doses and different periods of exposing on rots incidence and sprouting of tubers under long term storage was studied. Expose of tubers to high doses of vapour (resulted from evaporation of 0.5 or 1 ml/ liter space) for 6 h led to appear a very strong harmful effect on exposed tubers stored for 4 months. All tubers were decayed, collapsed and severely infected by rot pathogens. Expose of tu-bers to middle dose (0.25 ml/liter space) for 6, 12, 24, or 48 h then stored for 4 months at ambient temperature showed variable effects. Six or 12 h exposing led to slight reduction of rot incidence but it had not effect on sprouting in comparison to non-exposed tubers. On the other hand, exposing, for 24 or 48 h suppressed sprouting completely and reduced to very great extent rots incidence (%). Storage of tubers exposed to 0.25 ml/ liter for 24 h at high relative humidity (~90%) or under cooling (6-8 Cْ ) did not cause any reduction in compound efficiency. Expose of tubers to low dose of ES vapour (0.125 ml/ liter space) for dif-ferent periods showed that exposing for 6 or 12 h led to stimulatory effect on sprouting without ef-fect on rots incidence. Twenty four hours exposing led to decrease rots incidence and sprouting.These results clearly indicated that ES vapour had variable effects on exposed tubers depend upon dose and period of exposing.
Afficher plus [+] Moins [-]EFFECTS OF SOWING DATE AND PINCHING ON BROCCOLI SEED PRODUCTION
2007
A Abou El-Yazied | M Solaiman | A El-Gizawy | H.G Abd El-Gawad
A field experiment was conducted at the exper-imental farm of the Faculty of Agriculture, Ain Shams University, Shoubra Elkheima, Kalubia governorate, during 2002/2003 and 2003/2004 seasons to study the effects of three sowing dates, i.e., the first of each of September, October and November, and four pinching treatments (pinching the apical head just after appearance, pinching the main head at the marketable stage, pinching the axillary head just after appearance (disbudding) and without pinching) on broccoli plants (Brassica olerasea var Italica), cultivar “Emperor”. Plants were grown in Kaliobia under loamy soil conditions. Plants of the second sowing date (first of October) produced the tallest plants and the highest number of leaves per plant. Plants grown on the first of October plantation, pinching the main head at the marketable stage or the com-bination between them recorded the highest values of number of siliques/ plant, number of seeds/ plant, and seed yield.
Afficher plus [+] Moins [-]EFFECT OF POLYETHYLENE GLYCOL (PEG) AND PLANTING METHODS ON SWEET CORN PRODUCTIVITYEFFECT OF POLYETHYLENE GLYCOL (PEG) AND PLANTING METHODS ON SWEET CORN PRODUCTIVITY
2007
A Abou El-Yazied | I El-Oksh | Rawia, El-Bassiouny | Manal Attia
This study was conducted in loamy soil at Qaha Experimental Station, Horticulture Research Institute, ARC, Kalubia governorate, during 2002/2003 and 2003/2004 seasons to study the effect of PEG and planting methods on sweet corn productivity. The obtained results indicated that GSS 9377 F1 hybrid plants produced vigorous growth and higher early and total yield than those of Endeavor F1 hybrid. Direct seeding in the open field or under tunnels increased plant height, stem diameter, number of leaves/plant, plant fresh weight, unhusked ear weight, husked ear weight and total yield compared to transplanting methods. Transplanting produced the higher early yield ei-ther with open field or under tunnels. Primed seeds of sweet corn F1 hybrids (GSS 9377 and Endeavor) in PEG 6000 dalton for 6 hours at the concentration of 400 g/L produced taller plants with thicker stem diameter, higher number of leaves/plant and greater fresh weight, higher un-husked and husked ear weight, ear length, higher TSS as well as early and total yield compared to check untreated seeds
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