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Register a new userInfluence of Some Home Preparation and Storage Conditions on Ascorbic Acid Content of Infant Formula
دراسة تأثير التخزين و التحضير المنزلي لحليب الرضع على محتواه من حمض الأسكوربيك
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Added by
Tishreen University ورقة بحثية
Publication date
2015
fields
Pharmacy
and research's language is
العربية
Created by
Shamra Editor
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شملت الدراسة عينات من حليب الرضع للعمر الأول و الثاني لخمس شركات A, B, C, D, E. تم اتباع طريقةAssociation of Analytical Communities (AOAC , 2006) في تحديد حمض الأسكوربيك من خلال معايرته حجمياً باستخدام 6,2-دي كلوروفينول إندوفينول 2,6- Dichlorophenolindophenol (DCPIP). كان محتوى حمض الأسكوربيك في حليب الرضع للشركتين D, C قريباً من المصرح عنه في بطاقة البيان، أما حليب الرضع للشركات الباقية كان منخفضاً و وصل هذا الانخفاض إلى 34% في حليب الرضع للشركة E، و بقي المحتوى من حمض الأسكوربيك ثابتاً في عينات الحليب الجاف المحفوظة لمدة أسبوع بعد الفتح سواء في البراد أو في درجة حرارة الغرفة. انخفض المحتوى من حمض الاسكوربيك في عينات حليب عند تحضيرها باستخدام ماء حرارته 40°CأوC100 مقارنة مع تلك المحضرة بماء الصنبور و ازداد الانخفاض مع حفظ هذه العينات لمدة ساعتين بعد التحضير.
Vitamin C concentration was studied in samples of infant formula from 5 companies (referenced A-E) using the 2,6-Dichlorophenolindophenol titration (AOAC, 2006) method. Results revealed that ascorbic acid content in formulas D and C was the closest to its recommended daily intake (RDI) and to the concentrations which are mentioned on the label of the samples. Storage conditions at room temperature or in the refrigerator did not affect ascorbic acid levels. In comparison to vitamin C concentrations in milk dissolved in tap water, its levels decreased when water was warm (40°C) or hot (100°C), and its concentrations further declined in dissolved form kept for two hours after preparation.
References used
ALLEN, L.; DE BENOIST, B.; DARY, O.; HURRELL, R., Guidelines on food fortification with micronutrients.WHO and FAO, Switzerland, 2006, pages 43-91; 41 - 130
ANDERSON, R. H.; MAXWELL, D. L.; MULLEY, A. E.; FRITSCH, C. W., Effects of processing and storage on micronutrients in breakfast cereals. Food Technology, Vol. 30, 1976, pages 110-114
AOAC Official Method 967.21: Ascorbic Acid in Vitamin Preparations and Juices: 2,6-Dichloroindophenol Titrimetric Method. AOAC INTERNATIONAL 2006, 1968
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Sour orange (Citrus aurantium L.) seedlings were sprayed three times a
season with four levels of urea (45 % N) (2.5, 5.0, 7.5 and 10.0 g/L) and two
levels of ascorbic acid (150 and 300 g/L), each alone or in combinations.
Meanwhile the seedlings
of control treatment sprayed with distilled water
during 2010 growing season, twenty days intervals between each spray and
another. Results obtained at the middle of October of the same season,
indicated that the foliar spray with urea at the concentrations of 5.0, 7.5 and
10.0 g/L significantly increased leaves N and chlorophyll concentrations, leaves
number, seedling leaves area, seedlings height, main stem diameter and leaves
fresh and dry weight, especially at the foliar spray with 10.0 g/L. The means of
these parameters were 3.19%, 66.80 SPAD, 146.66 leaves/seedling, 3700.00
Cm², 83.66 Cm, 4.50 mm, 4.70 g, 1.53 g, respectively. Meanwhile ascorbic acid
spray at two concentrations unsignificantly affected all parameters, except
leaves chlorophyll content, leaves number and seedling leaves area. Most
treatments of combinations spray with urea and ascorbic acid significantly
affected all studied parameters, especially the treatment of foliar spray of urea
and ascorbic acid at a concentration of 10.0 g/L and 300 mg/ L, which gave the
highest means of leaves N concentration, leaves number, seedling leaves area
and leaves fresh and dry weights, and it unsignificantly differs from the
treatments which gave the highest means of seedlings height, main stem
diameter and percentage of leaves dry matter weight .
The study was carried out on trifoliate orange rootstock trees (Poncirus trifoliata L.)
at Ciano Research Station where the trees were sprayed with nutrients or gibberelic acid
GA3 or togethers, beside the control (without spraying). Different trea
tments of seed
storage were tested in order to study their effect on seed viability to increase it. The seeds
were stored for three months using four treatments: (a) seed storage in fruits at +4˚C, (b)
Storage in juice at +4˚C, (c) Storage at lab temperature, and (d) seed storage at fridge
temperature +4˚C. The results showed that all spraying treatments were positive at
postharvest, as compared with the control. However, treatment of seed storage inside the
fruit gave the highest significant germination rate for all spraying treatments. Treatments
of spraying with nutrients were the best. The viability of seeds considerably decreased for
all treatments of seed storage at fridge temperature +4˚C, whereas germination was zero for
seed stored in juice and seed stored at lab temperature.
Pastrami, manufactured from beef and abdominal fat and of a ratio of 3 meat to 1 fat,
was stored under refrigeration at (4±2 °C) and storage times (0, 15, 30, 60, 120, and 180
days). The effects of storage times on the most important chemical, micr
obiological and
sensory properties of pastrami were investigated.
The results of chemical analyzes showed that the studied pastrami conformed to the
Syrian Standards in terms of the proportion of salt and fat content, and it nearly conformed
to the standards in terms of humidity. The results also showed a slight decrease in the
percentage of moisture, fat and protein, and an increase in each of the acidity, proportion of
total volatile nitrogen, soluble nitrogen and peroxide value in pastrami with the progress of
the storage period at the temperature degree (4±2 °C). The microbial tests showed that
pastrami is free from some sickening organisms especially salmonella and E. coli. It also
showed that the census of the aerobic bacteria, yeasts and fungi was within the limits of the
Syrian standards. The results showed deterioration in the microbial properties of stored
pastrami with the progress of time; pastrami became invalid from a microbial point of
consumption after two months of storage as a result of the big number of aerobic bacteria,
yeasts and fungi. The sensory tests showed deterioration in the organoleptic characteristics
of storage with the progress of time, the deterioration was clear after two months of
storage; pastrami became unacceptable in terms of taste, color, smell and texture.
The aim of this research is to study the most important physical, chemical and
microbial changes in several kinds of infant milk available in local markets. The milk
samples were studied in conditions similar to those used by mothers when they prep
are
infant milk bottles at their houses. The results showed that moisture content increased in all
samples from approximately 1% to 3.2-4.4% after storage for 9 days. Acidity increased
considerably from 0.14% to 0.2%.
The results showed that peroxide value passed the allowable limits (0.25) and
reached about (0.47) in samples stored for 9 days at room temperature. However, the value
for samples stored in the refrigerator ranged between (0.25-0.29). The free acidity number
of fat for all samples specially the refrigerated ones was within the natural limits (<0.5).
Chromatographic analyses showed apparent differences in fatty acid percentages between
the kinds of milk. The rate of lenoleic acid (C 18-2 ) decreased during storage in all samples
and in all conditions.
Soluble nitrogen increased in all samples at the end of storage and the highest value
was 0.49% in Nido milk samples. The solubility of milk samples was checked during
storage and was found to decrease very little ( 1%).
The total count of aerobic bacteria showed that all samples conform to the Syrian
standards (No. 197, 1996) during the first six days of storage, but they passed the upper
limits at the end of storage. However, all samples were free of pathogenic microbes .
Green tomato fruits of different studied hybrids such as, Amal, Steel,
Tartila, and 2-75/96, which had been grown in a greenhouse at Abi- Jarash
Farm were picked up and stored at temperatures of 12 c and 20 c for 29 days.
The fruits, which were st
ored at 12 c had been transferred to 9 cْ, and then
stored for an additional period of two weeks. The chemical composition of the
stored fruits was evaluated, which included: acidity percentage, total soluble
solids, and the quantity of vitamine C. The ratio of fruit weight loss during
storage was studied as well.
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