2024-03-29T15:25:11Z
https://ajfs.journals.ekb.eg/?_action=export&rf=summon&issue=3483
Alexandria Journal of Food Science and Technology
1687-3920
1687-3920
2017
14
2
Evaluation of A Constructed Unit for Biodiesel Production From Expired Reused Vegetable Oils
Sehsah
M.
Omara
I.
Biodiesel (Fatty Acid Methyl Esters) has become one of the most promising alternative source of energy in the world. The aim of this study was to design and construct a laboratory production unit to produce 500 liters per day of biodiesel from waste vegetable oil (WVO) and to investigate the effect of two different catalysts on some properties of biodiesel production.The biodiesel production unit was constructed at the Department of Agricultural-Engineering, Faculty of Agriculture,Kafr El-Sheikh University, Egypt. The biodiesel production unit consisted of the two centrifugal pumps, an electrical heater and a thermostat type RTM were fixed inside the main tank and isolated by aluminum tap. The unit was provided the three electrical valves to be used for controlling vegetable oil’s flow-rate and biodiesel production. The vegetable oil waste was collected from several restaurants, the food technology department, kafr elsheikh Universityand from the food industry in Kafr elsheikh and Alexandria governorates. Two catalysts; (Methanol with sodium hydroxide and ethanol with sodium hydroxide) were added into the unit during the process of biodiesel production. The collected WVO was screened to remove all Food residuals first. The oil was then heated for 30 min to remove the water content. The manufactured biodiesel unit is to produce 500 liter/day of biodiesel from the WVO under local conditions. The measured energy requirements to produce 60 liters biodiesel from WVO were 1.31 kWh, 1.14 kWh and 0.97 kWh for WVO at feeding rate of 12.76 liter per min, 7.05 liter per min and 4.84 liter per min, respectively. Standard procedures were followed to determine the product properties. The flash point of biodiesel were 60°C, 64°C, 64°C, 68°C for B100 (ethanol catalyst), B100 (methanol catalyst), B20 (ethanol catalyst), B20 (methanol catalyst) respectively. The HHV for biodiesel were 41.98 MJ/kg, 41.74 MJ/kg, 42.06 MJ/kg and 41.83 MJ/kg for B100 (ethanol catalyst), B100 (methanol catalyst), B20 (ethanol catalyst), B20 (methanol catalyst) respectively.
Biodiesel
waste vegetable oil
biodiesel production unit
2017
12
01
1
8
https://ajfs.journals.ekb.eg/article_16280_acf9ef564cee2c0f830a2de7e1560470.pdf
Alexandria Journal of Food Science and Technology
1687-3920
1687-3920
2017
14
2
Bio-Texturisation of Soy Protein Isolate
Dalia
Eshra
The possibility of using microbial transglutaminase (MTGase, 2.3.2.13) on bio-texturising of soy protein isolate is the main object of this study. Covalent cross-linking of proteins by MTGase is easy and simple for application, safe and well controlled process than commercial methods used for protein texturisation. Two commercial preparations of MTGase were used for restructuring soy protein isolate (SPI). The investigation of the product (gel) formed was evaluated using textural profile analysis (TPA). The results indicated that using of MTGase for texturising of SPI enhance greatly most of TPA parameters. The most affected parameters were hardness, cohesiveness and gumminess. Bio- texturising of proteins is a promising tool for restructuring and modifying the structure net work of protein molecules.The cross-linking reactions promoted by the action of MTGase allowing for the development and widespread use of new and improved functional properties in food industry.
Bio-texturisation
microbial transglutaminase
Plant proteins
soy protein isolate
textural parameters
2017
12
01
9
16
https://ajfs.journals.ekb.eg/article_16281_513f50573fcf0a68c05a9eb5d3522faf.pdf
Alexandria Journal of Food Science and Technology
1687-3920
1687-3920
2017
14
2
Effect of Different Cooking Methods on Natural Antioxidants in Pumpkin (Cucurbita moschata) Products
Tesby
Lotfy
Marwa
Mahfouz
M.
Youssef
The present study aimed to investigate the effects of various cooking methods on antioxidant content and radical scavenging activity of pumpkin. Three heat treatments were applied, namely,blanching, and stir frying for cubes(1.5×1.5×1.5 cm) and roasting for slices (0.5mm) to produce soup, juice and roasted pumpkin. The results indicated that carotenoids content ranged between 11,07 IU/100g (soup) and 892 IU/100g (juice).Roasted product exhibited significantly (P≤0.05) the least flavoniod content (12.09g/kg), while soup possessed significantly (P≤0.05) the highest content(17.96 g/Kg). Lycopene content (0.15 mg/100g) was found to be significantly(P≤0.05)the least (in soup produced from cubes blanched for 4 mins). In contrast, the counterpart raw juice had significantly (P≤0.05) the highest lycopene content (0.70mg /100g). Total polyphenols content of stir fried product was significantly (P≤0.05) the least(406.25 g/kg), while roasted product exhibited significantly (P≤0.05) the highest polyphenols content (670.18g/kg). It was obvious that raw juice possessed significantly (P≤0.05) the highest DPPH (63.79%), on contrary to roasted product being significantly (P≤0.05) the least antioxidant activity as assessed by DPPH method (30.31 %).The H2O2 scavenging (2.85 %) was found to be significantly (P≤0.05) the highest ( in soup produced from cubes blanched for 4 min) .While, the raw juice has significantly(P≤0.05)the least H2O2 scavenging (0.32%).So, It is necessary to apply the most proper cooking conditions (temperature and cooking time) to avoid any degradation of the bioactive compounds present in pumpkin. The results revealed the superiority of blanching process since it maintained the bioactive compoundsin pumpkin without any deteriorative effects.
Natural antioxidants
Antioxidant activity
cooked pumpkins
blanching
stir-frying
juicie
soup
roasting
2017
12
01
17
24
https://ajfs.journals.ekb.eg/article_16282_d0001edc81e4240b39727e4495cf699b.pdf
Alexandria Journal of Food Science and Technology
1687-3920
1687-3920
2017
14
2
Formulation and Evaluation of Some Novel Breakfast Blends Made from Cereals and Legumes
Rehab
Mostafa
Azza
Abd-El Haleem
Salwa
Gabal
Four samples of breakfast cereal-legume blends were generated by mixing the flours (wheat, maize, rice, lentil, bean, chickpeas and kidney beans) with almond, bran and dates, in addition to others additives such as powdered skimmed milk, honey, baking powder, baking soda and flavoured (vanillin + cinnamon). Gelatinization of the grains and legumes starch was produced by roasting to obtain ready to eat breakfast cereal products. They were subjected to proximate, sensory, minerals, vitamins, anti-nutrients and acrylamide analysis. The products obtained were also served dry with warm milk to 10 panelists along with control sample to be evaluated for colour, taste, odour, texture and overall acceptability using a 9 point hedonic scale. The results showed the following ranges: Proximate composition(%): Moisture (12.95- 16.67), protein (7.71-13.06), crude ether extract (4.48-7.99), ash(2.30-2.52), carbohydrate(62.84-71.80),crude fiber (3.13-3.98) Energy ranged from 358.36 to 375.71kcal. Minerals analysis reported the following ranges (mg/100g):Fe (3.55-4.93),Zn (8.60-9.38), Mn (0.85-1.63), Ca(429.55-641.19), Mg(91.33-94.80), Na(24.66-39.17) and K (4.94-5.52). Vitamins analysis revealed the following ranges (mg/100g): Ascorbic acid (5.86-7.68), B2(1.46-1.68), B3(3.94-4.64), B9(0.487-0.585), ß-carotene (3.91-6.16), E(4.24-5.63). The anti-nutritional factors showed the ranges: Trypsin inhibitor (13.61TIU/mg-24.71TIU/mg), phytic acid (129.10mg/100g-220.77mg/100g), haemaggluttinating activities (128.59U/100g-284.50U/100g), alkaloids (64.69 mg/100g-183.33mg/100g), and oxalicacid (19.77mg/100g-88.93mg/100g). Protein digestibility exhibited values ranged from83.20 % to 90.11%. The acrylamide content of the four blends ranged from 281.18μg/kg to 363.00μg/kg.
Breakfast cereal-legume blends
acrylamide
anti-nutritional factors
2017
12
01
25
34
https://ajfs.journals.ekb.eg/article_16283_e21e7371fe8fe9915d0e7316a552c7ed.pdf