Journal      [Total: 31540 ]

Efficient enzymatic conversion of lactose in milk using fungal?-galactosidase

Baraka Abdelsalam Gomaa, 2020

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?-galactosidase (?-gal, E.C. 3.2.1.23) was detected in different fungal cultures and their fermentation factors wereoptimized, as well as ?-gal was purified and characterized from the selected fungal strain. Moreover, the potential impact of fungal ?-gal on free lactose-flavored milk production was investigated. Aspergillus terreusNRRL 280showed the highest ?-gal specific activity which grown at 37 ?C for 7 days compared to other fungal strains. Also,A. terreusNRRL 280 showed their highest ?-gal activity at the optimized growth conditions of 37 ?C, pH 4.0 for 7days. ?-gal enzyme was purified from A. terreusNRRL 280 using 40-60% ammonium sulfate saturation with22.15% yield and 1.11 purification fold. Purified ?-gal exhibited their optimal activity at 60 ?C, pH 6.0, and 80min of incubation time, as well as it was is quite stable for the heat treatment. ?-gal activity was significantlyenhanced with 5 mM Ca2+, Mn2+ and Mg2+, while it was were sensitive to Fe3+ and EDTA. The highest lactosehydrolysis (94.16%) and 23.9 g/l of glucose were recorded for flavored raw skim milk treated with 7.0 U/l milkof ?-gal at 6th day of storage period. The flavored milk made from raw full cream cow milk treated with 5.25 U/lof ?-gal was recorded the highest sensorial attributes scores followed by those of made from raw skim milk withthe same ?-gal level. It could be concluded that using of fungal ?-gal in lactose-free flavored milk may prove to bebeneficial for intolerant lactose people.


IMPACT OF ALGA FED BEE VENOM ON MASTITIS AND MILK QUALITY

Baraka Abdelsalam Gomaa, 2020

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Dairy goat mastitis is a disease of great economic importance worldwide as in dairy cows. Bee venom (BV) is synthesized in the venom glands of worker. It exhibits a variety of biological activity including anti-inflammatory effects and antibacterial action. The current study was intended to assess whether ordinary or alga-fed BV- injection (intramamary or subcutaneous) has therapeutic potential against goats sub-clinical mastitis and improves the chemical and bacteriological quality of milk. Honey bees were fed pollen supplement diets containing a different conc. of Spirulinaplatensisalga (40, 50 and 60%). worker’s sealed brood, bee strength and Bee venom weight were determined. The effect of ordinary or alga-fed BV- injection (intramamary or subcutaneous) on goats sub-clinical mastitis was investigated. Hematological and biochemical analyses of blood were performed. Milk samples were cultured to isolate and identificate of responsible pathogens. Somatic cell count (SCC), chemical and bacteriological propertied of milk were determined. The results of bee feeding showed that the colonies fed pollen supplement diet containing 50 % S. platensis(GB) had the maximum bee venom weight, area of sealed worker brood and mean number of combs covered with bees. From animal data, the goat, s group injected intramamary with alga- fed bee venom after 14 days of treatment showed the highest hemoglobin, erythrocytes, Ig G level and the lowest leucocytes count in blood. The blood total protein, albumin and globulin levels slightly decreased in BV treated groups after 14 days of treatment compared to control group. Also, milk analysis revealed that the normal levels of casein, fat, lactose, calcium and the lowest counts of total bacteria, staphylococci, streptococci, coliformes and somatic cells were recorded with the goat, s group injected intramamary with alga- fed bee venom after 14 days of treatment. Hence, alga- fed bee venom treatment increased the rate of bacteriological treatment and reduced SCC at gland compared with control. Isolated pathogenic bacteria were coagulase- negative Staphylococcus, Staphylococcus aureus, Streptococcus sp. and E. coli. It could be concluded that the sub -clinical mastitis goats - intramamary injection with alga -fed bee venom improves the immune response of animals against the etiological agent of mastitis, the chemical and bacteriological quality of milk and may be helpful in improving recovery in dairy goats


Quality Characteristics of Processed Cheese Fortified with SpirulinaPowder

Baraka Abdelsalam Gomaa, 2020

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Spirulina is a rich source of nutrients viz., essential amino acids, essential fatty acids, carotenoids and vitamins. The study was carried out to evaluate of Spirulina maxima addition as source of nutrients, antioxidants and color on processed cheese properties. Materials and Methods: Processed cheese analogue treatments were supplemented with Spirulina maxima powder (1, 2 and 3%). The chemical, physical, color and sensorial properties of processed cheese analogue supplemented with S. maxima were evaluated through 3 months of cold storage (7EC). Also, the antioxidant capacity of S. maxima processed cheese analogue treatments was determined. Results: The spreadable processed cheese analogue with 3% S. maxima powder had higher chemical components except ash compared to control cheese. The results of physical properties showed that the penetrometer reading of the S. maxima processed cheese treatments was higher than those of control allover storage period, while oil separation and melt ability were lower. The S. maxima processed cheeses were more green (a-value) and lower whiter (L-value) than those of control. The highest free radical scavenging activity (57.24%) was recorded for S. maxima processed cheese analogue treatment (3%). From the sensorial results, the S. maxima processed cheese analogue (1 or 2%) treatments was higher acceptable compared to those of 3%. Conclusion: Hence, adding S. maxima powder (1 or 2%) during processed cheese analogue manufacture let the cheese to develop special color (green), high nutritional value, antioxidant activity and sensorial scores


Active Components of Squid Ink and Food Applications

Nesren Mohamed Bondk, 2020

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In Egypt, squid ink is disposed of during squid preparation, which may cause environmental pollution and health problems. Therefore, this study was carried out to make use of the active ingredients found in the squid ink as by-products. The chemical composition, the mineral, total phenols, and flavonoids contents of squid ink were determined. DPPH radical scavenging activity, cytotoxicity, and antitumor activity of squid ink on human tumor cell line (Lung carcinoma cell line) were also tested beside its antimicrobial activity. Two mixtures of black or brown squid ink sauce were prepared. The results indicated that the antioxidant activity was 91.66%. The results of the cell viability and toxicity assay of squid ink indicated that as the concentration of squid ink increased the viability percentages were decreased, while inhibitory activity percentages were increased. The IC50 [the concentration causing the death of 50% of the human tumor cell line (Lung carcinoma cell line A549)] was 22 ?g/mL. The results also indicated that the squid ink had antimicrobial activity against Bacillus subtilis, Aspergillus fumigates, Aspergillus niger, Candida albicans, Staphylococcus aureus, Escherichia coli, Klebsiella pneumonia, and Proteus vulgaris with zone inhibitions of 19, 18, 12, 13, 11, 13, 12 and 10 mm, respectively. The overall acceptability scores of the black and brown squid ink sauces were 9.35 and 10, respectively. In conclusion, the formulated squid ink sauces with a strong odor, high acceptability, and different colors as well as anti-oxidant, anti-microbial and anti-cancer activities can fulfill the desires of many consumers. Keywords: Squid ink, Anti-oxidant, Anti-microbial


Hepatoprotective Effects of Mulberries and Cape gooseberry on Thioacetamide Induced Liver Injury in Rats.

Nahed Zaki, Nasra Mohamed Abd El-Hak, 2020

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The objective of this study was to evaluate the hepatoprotective effects of black mulberry, white mulberry and cape gooseberry on the thioacetamide (TAA)-induced rats hepatocytes damage in vivo. The data showed that significant differences in the total phenolics and total flavonoids content, between the black mulberry, white mulberry and cape gooseberry. These findings revealed that black mulberry had more total antioxidant activity. The highest levels of glucose, fructose and arabinose were detected in white mulberry. The 54 male albino rats used separately into nine groups of 6 rats each group for 4 weeks as follows: Group 1 served as a normal control. Groups 2-9: Rats injected with TAA (100 mg/kg, i.p.) twice a week. Group 2 kept as positive control. Groups 3 and 4 were given 5 and 10 ml/kg b.w rat of black mulberry. Group 5 and 6 were administered 5 and 10 ml/kg b.w rat of white mulberry. Groups 7 and 8 received 5 and 10 ml/kg b.w rat of cape gooseberry. Finally, Group 9 was treated daily with silymarin (100 mg/kg). The effects were compared with a known hepatoprotective agent and silymarin. Alteration in the morphological and the levels of biochemical markers of hepatic damage were studied in the groups. TAA has elevated the liver function, kidney function, lipid profile and MDA levels and reduced the serum levels of albumin, HDL cholesterol, and CAT. Treatments with black mulberry, white mulberry and cape gooseberry juices brought back the altered levels of biochemical markers to the near normal levels at doses independently. Histological examination of the liver tissues confirmed the hepatoprotective effect of fruits juices. These results were documented by the amelioration signs in rat’s hepatic architecture. Conclusion: our study demonstrated the ameliorative effects of black mulberry, white mulberry and cape gooseberry juices against TAA induced hepatotoxicity in rats. Keywords: black mulberry, white mulberry, cape gooseberry, antioxidants, liver fibrous


Evaluation of gluten-free noodles fortified by Spirulina algae

Salwa Jabal, 2020

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Spirulina is a unique algae. It is very rich in nutrients. Therefore, gluten-free noodles made from potato flour was fortified to raise its nutritional value by adding 5, 10 and 15% spirulina algae, as it is a suitable food for people suffering from celiac disease. The chemical composition of the spirulina algae, potato flour and gluten free noodles were determined. Vitamins, minerals, heavy metals, amino acids, pigments contents and in vitro protein digestibility were determined. The sensory characteristics of gluten-free noodles fortified with spirulina algae were also evaluated. The results indicated that heavy metals contents of spirulina algae (arsenic, cadmium, lead and mercury) were under the permeable limits according to the Egyptian Standards. The results indicated that the spirulina algae was rich in vitamins (with highest contain of inositol, 57.78 mg/100g), minerals (P 2100, K 1996, Ca 728 and Fe 438 mg/100g), from the determined pigments phycocyanin pigment showed the highest content (13.85%) and chlorophyll (1.5%). The total essential amino acids and non-essential amino acids of the spirulina algae were found approximately 38.97% and 61.05%of protein content, respectively. Addition levels of 5%, 10% and 15% of spirulina algae to potato flour led to increase the contents of protein by about 24%, 49% and 73% respectively, Ca by 66, 275 and 423% respectively, P by 528, 1192 and 1734% respectively, K by 40, 84 and 159% respectively, Fe by 348, 576 and 952% respectively and in vitro protein digestibility values by 11, 21 and 32% respectively compared to control sample. Results of the sensory evaluation revealed that addition of spirulina algae powder to potato flour at levels up to 15% could be recommended, since all the produced noodles scored higher values for all the evaluated sensory characteristics compared to control sample.


Effect of Drying Process on the Quality of Table Olives

Rania Mohamed el meselhy, Hamdy Ahmed Badawy, 2020

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The present work aimed to investigate the effect of drying conditions (temperature and time) on the quality of green table olives (Oleo eurapaea L.) Picual cultivar during the drying process in order to obtain the best processing conditions to avoid losses and keep product quality of table olive. Oven temperature varied from 50 to 70°C drying rates were determined and the proximate analysis of dried green olives was evaluated by analysis of moisture, protein, ash, fiber and oil contents. Peroxide value, acidity and fatty acids composition of extracted oil from olive samples were determined. Consumer's acceptance test was applied. A comparison of fresh and dehydrated olive showed that oven drying led to decrease of crude protein. Crude fiber content showed a slight increase during drying and may have undergone some alterations in its structure due to Maillard reactions. Ash content also showed a slight variation but may be considered as practically unchanged. Fatty acid analysis revealed that table olives were especially rich in oleic acid and the fatty acid composition did not show significantly change during drying. Olives can be considered as a product with a satisfactory microbiological quality and nutritional value with regard to bioactive ingredients. It brings about substantial reduction in mass and volume which has important economic benefits through reducing packaging and minimizes the volume of containers with maximum net weight, thereby lowering transportation costs, avoids losses and keeps high quality of longer shelf-life of table olives. Keywords: Table olives; oven drying; dehydration; consumer’s acceptability


Using Nanotechnology in Bleaching Vegetable Oils

Rania Mohamed el meselhy, Mounir Eid, 2020

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The present study aimed to investigate the efficiency of nanotechnology in bleaching three important Egyptian oils (soybean, corn and sunflower). The raw bleaching earth powder was milled for 10 h in a planetary ball mill. X-ray diffraction analysis (XRD) and transmission electron microscopy (TEM) were used to investigate morphology, crystallite size, lattice strain and particle size of as-received and milled powders. The mechanical alloying process succeeded to obtain nano-sized bleaching earth powders after 10 h of milling and the morphology appeared rod with 46.6 nm in length and 4.46 nm in diameter. The milled nano-sized bleaching powder was used in bleaching of oils under study. Comparing color indices, peroxide values and spectral absorbencies at 232, 270 nm for the resulted bleached oils with the unbleached and control ones bleached with raw bleaching earth, it was concluded the high bleaching efficiency of nano-sized bleaching earth in reducing color indices, peroxide values and spectral absorbencies at 232, 270 nm.


Rapid Authentication of Extra Virgin Olive Oil using UV and FTIR Spectroscopy

Rania Mohamed el meselhy, 2020

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Spectroscopic examination in the ultraviolet (UV) can provide information on the quality of an oil, its state of preservation and changes brought about by technological processes. The absorption at the wavelengths 232 nm and 270 nm in cyclohexane is due to the presence of conjugated diene and triene systems, respectively, resulting from oxidation processes and/or refining practices. These absorptions are expressed as specific extinctions conventionally indicated by K (also referred to as "extinction coefficient"). In this work, the specific extinctions at 232 nm and 270 nm in cyclohexane are calculatedfor a concentration of 1% w/v for extra virgin olive oil adulteration with sunflower, corn oils in their binary admixtures in different concentrations (0, 5, 15, 25 and 100% w/w). Results revealed that the adulteration will be detected easily by UV absorbance at 270 nm because sunflower oil showed a shift out of the permitted range at 15% upward higher concentrations added to extra virgin olive oil. Also, corn oil will be detected if present in 15% upward higher concentrations in blends with extra virgin olive oil. The calculated ?K allowed the detection of adulteration in extra virgin olive oil at the concentration of 15% upward higher concentrations of adulterant sunflower and corn oils; and this is the lowest detectable value in adulterated extra virgin olive oil. Also, Fourier Transform Infrared Spectroscopy (FTIR) is used as an effective analytical tool in order to determine extra virgin olive oil adulteration with sunflower, corn oils in their binary admixtures in different concentrations (0, 5, 15, 25 and 100% w/w). A band around 2925 cm-1 along with its intensity (assigned to C–O stretching and symmetric stretching vibration of the aliphatic CH2 group) along with a very strong band along with its intensity located at 1743 cm-1 (assigned to the C=O stretching band of the ester group) were important to detect concentration of 5% adulterants SO and CO in EVOO. The present work successfully achieved its aim included in the applications of UV and FTIR spectroscopy as rapid, cheap, nondestructive, authenticity measuring tools to assess the adulteration of extra virgin olive oil with other edible oils such as corn and sunflower oils in detection limit 15% for UV and 5% for FTIR spectroscopy. Library searching in the FTIR region is a well established and powerful way which was used in comparison and matching of measured spectra. Keywords: Authentication; UV; FTIR; Spectroscopy; Extra virgin olive oil; Sunflower oil; Corn oil


Characterization of ?-glucan gum for food applications as influenced by genotypic variations in three hulless barley varieties

Amal Abdel-Haleem, walid Shehata, 2020

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Three hulless barley varieties were grown under normal conditions during 2017/2018 and 2018/2019, to improve their agronomic yield, and to assess how the genotype influences ?-glucan contents, and its structural, thermal, rheological, and functional properties, as intended to be used in food applications. The extracted gums with hot water at 55 °C and pH 8.0, showed contents from 5.75% to 6.41% (w/w), and concentrations from 68.55% to 79.29% of ?-glucan, with some starch and protein impurities. The results of the agronomic trail indicated the highly significant (P_ 0.01) influence of the genotype on all studied characteristics, and on the ?-glucan contents (0.28?? and 0.33??) at both seasons. The morphology of the three gums was significantly different in the distribution and structure of networks. Peak intensities of the –OH and –CH groups and CH2 stretching were higher and wider in Giza129 and Giza131. ?-Glucan networks melt from 71.5 to 87.18 °C, and Giza131 exhibited the highest thermal stability. The aqueous dispersions (1%) of ?-glucan gums exhibited a non-Newtonian behavior, and Giza130 presented the highest significant (P _ 0.05) apparent viscosity (?) and foaming stability. Giza129 showed the highest significant water and fat binding capacities, whereas Giza131 showed the highest significant foaming capacity. ?-Glucan gums showed different potentials in food applications as fat replacers, stabilizers, thickeners, and foaming agents in food systems. This study suggests planting the proper barley variety in breeding and genetic improvement programs to supply the food industry with the expected ?-glucan content with consistent structural, thermal, rheological, and functional properties. Keywords: barley ?-glucan, genotypic factor, structural characterization, thermal, rheological and functional properties


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