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Register a new userPreparation of Caramelisation Products and Defining their Reducing Power
تحضير منتجات الكرملة و تعيين قدرتها الإرجاعية
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Damascus University ورقة بحثية
Publication date
2007
fields
Chemistry
and research's language is
العربية
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Shamra Editor
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حضرت منتجات الكرملـة ( CPs ( Products Caramelisation لأربعـة سـكاريدات مختلفـة (فركتوز، غلوكوز، لاكتوز، كسيلوز) بتسخين المحاليل السكاريدية في الدرجة 100 م° مدة ثلاث ساعات في أوساط مختلفة الحموضة (5.2 ، 4 ، 7 ، 10 pH) . درسـت منتجـات الكرملـة ( CPs ) طيفيـاً باستخدام المطياف الضوئي في المجال المرئي و فوق البنفسجي، حيث لوحظ ازديـاد تـشكل المركبـات السمراء و منتجات التفكك الحراري المتوسطة بازدياد زمن التسخين عموماً، و تختلف سرعة تشكلها وفقاً لنوع السكاريد و حموضة الوسط. عينت القدرة الإرجاعية لمنتجات الكرملة، إذ وجد أن منتجات الفركتـوز أعلى قدرة إرجاعية مقارنة بمنتجات السكاريدات الأخرى في الوسط القلوي. أخيراً درس كمياً تغير تركيز السكاريدات في أثناء التسخين باستخدام تقانة الكروماتوغرافيا السائلة عالية الأداء HPLC.
Four model caramelisation products (CPs) have been prepared by heating different Saccharides solutions (glucose, fructose, lactose and xylose) at 100°C for 3 hours at different pH( 2.5, 4, 7 and 10). Both Browning and intermediate thermal degradation products {the caramelisation products} were studied using ultraviolet /visible spectrophotometer. Generally, the results showed that CPs increased with increasing heating time, and the formation rate depends upon the type of Saccharides and pH value. The reducing power of the four distinct CPs was defined, also. Among all the Saccharides tested, fructose CPs exhibited the highest reducing power values in alkaline solutions. Finally, the concentration changes of Saccharides during heating were quantitatively defined by using high performance liquid chromatography HPLC.
References used
Ajandouz, E. H., Tchiakpe, L. S., DalleOre, F., Benajiba, A., & Puigserver, A. (2001). Effect of pH on caramelization and Maillard reaction kinetics in fructose-lysine model systems. Journal of Food Science, 66, 926–931
Benjakul, S., Visessanguan, W., Phongkanpai, V.and Tanaka, M. (2005). Antioxidative activity of caramelisation products and their preventive effect on lipid oxidation in fish mince , Food Chemistry 90 ,pp. 231–23
Berg, H. E., Van Boekel, M. A. J. S. (1994). Degration of lactose during heating milk, Netherlands Milk and Dairy Journal,48, pp. 157-175
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six new products using Knoevenagel condensation of isophthalaldehyde and
terephthalaldehyde have been prepared with the following active methylene
compounds: malononitrile, methyl cyano acetate, ethyl cyano acetate, dimethyl
malonate and diethyl m
alonate. We determined the optimum conditions of the
reaction by studying the effect of solvent and catalyst nature and reaction
conditions on the condensation.
يعد الميتانول و الإيتانول من أكثر المحلات شيوعاً، و بما أن درجة غليانها أقل من مئة
درجة مئوية فإنها تتطاير بشكل سريع. و على سبيل المثال، يستعمل الميتانول في تصنيع
الأصبغة و العقاقير و العطور.. و هو شديد السمية، لذلك من الضروري تطوير محسات لكشفه.
أ
ما غاز الأمونيا فهو من ملوثات الهواء و له مصادر كثيرة مثل صناعة الأسمدة و أنظمة
التبريد.. و من هنا أهمية كشفه.
The purpose of this research is to deduce the basis for calculating the cost of honey bee
products since the actual costing of various levels on accurate basis is the right starting
point for achieving all the goals of the cost systems. Because the
actual cost is the basis of
planning, control and reduction of that cost. Lack of information to properly determine
product cost may cause choosing unhealthy competitive strategies, and make bad
decisions, whether it related to product pricing or product selection.
The research objective was reached through an analytical study of previous studies that
discussed the economic feasibility of honey bee production projects in a variety of
environments. In addition, a field study was carried out on the working beekeeping firms in
Lattakia governorate during the period between the month of 11/2017 and the end of the
month 8/2018.
A number of conclusions were reached on the determinants of the cost of honey bee
products, including the need to rely on the variable cost approach in preparing the list of
honey product costs, the adoption of the production season as a period for the preparation
of this list and a number of conclusions regarding the basis for calculating the depreciation
of the assets of the honeybees and classified it as fixed cost which must included in the
income statement for the financial cycle which ends at the end of the production seasons
on 31/10 of each year.
This research was conducted at the Faculty of Agriculture, Department of
Food Science laboratories to isolate lactic acid bacteria from some Syrian milk
products (milk, yogurt, cheese) and determine some morphological,
physiological characteristic and the ability of these isolates to ferment sugars.
Some samples of alumina supporting with sulfate ions and molybdenium were
prepared by impregnation method. Supported samples were calcinated at 550°C for 6h.
Presence of sulfate ions and molybdenium lead to decreasing of the specific surface area o
f
alumina, and in the ease of molybdenium the decreasing value was higher. The total pore
volume was decreased with the pore size was increased. XRD patterns showed that the
incorporation of sulfate ions and molybdenium did not affect crystalin structure of
alumina. FTIR spectra showed the bonding between sulfate ionsmolybdenium
and
alumina. The TG-DTA studies showed that the losses mass was decreased when the sulfate
ions and molybdenium were incorporated, sulfate ions and molybdenium oxide
decomposed at ~700°C and ~800°C respectively .
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