The Scientific Society of Food Industries, Alexandria, Egypt.
Alexandria Journal of Food Science and Technology
1687-3920
16
2
2019
12
01
Effect of Roasting on Physicochemical Properties of Cocoa Beans
1
7
EN
mohamed
m
youssef
Food Science and Technology Faculty of Agriculture - Alexandria University
m_m_youssef@yahoo.com
10.21608/ajfs.2019.14658.1012
Cocoa beans (Theorem cocoa) are the main raw materials used in chocolate manufacture. Roasting is the most<br />important technological process in production of cocoa products. It is the main process in the development of aroma<br />and taste of cocoa beans. Maillard reaction and Strekher degradation take place during roasting process, where the<br />flavour compounds of cocoa are produced. It was found that roasting temperatures at a range from 90 to 110°C were<br />optimum for producing high quality chocolate, by using the Response Surface Methodology (RSM). The desirable<br />flavour components of cocoa beans are developed due to the pyrazines which are produced during roasting process.<br />This process affects the chemical composition (protein, fat, carbohydrates, ash, minerals and vitamins) of cocoa beans.<br />The stability of polyphenols in cocoa beans is influenced by the conditions of the roasting process. Roasting causes<br />a decrease in the polyphenols content of cocoa beans up to 98%. The roasting process of cocoa beans should be optimized<br />(temperature and time) to produce final products of high quality.
Cocoa beans,roasting,flavour,pyrazines,chocolate
https://ajfs.journals.ekb.eg/article_71652.html
https://ajfs.journals.ekb.eg/article_71652_6e6d30f204e21951f4786165d327a9d7.pdf
The Scientific Society of Food Industries, Alexandria, Egypt.
Alexandria Journal of Food Science and Technology
1687-3920
16
2
2019
12
01
Reducing the Soluble Oxalate and Phytic Acid in Taro Corm Chips by Soaking in Calcium Salt Solutions
9
16
EN
samaa
saleh
Food Science Department, Faculty of Agriculture (Saba Basha), Alexandria University, Egypt
samaa8mhs@yahoo.com
10.21608/ajfs.2019.20766.1015
Taro (Colocasia esculentum (L)) corm is one of the most nutritious and easily digested foods, but unfortunately<br />contains anti-nutritional factors such as oxalates and phytic acid .The oxalates which can lead to risks of kidney<br />stones, while phytic acid reduces bioavailability of minerals. Therefore, the anti-nutritional factors must be removed<br />or decreased before utilization of corm as food by carrying out chemical or physical process such as soaking, boiling,<br />fermentation or cooking. So, the incorporation of chemical and physical methods is expected to be a very efficient ways<br />of processing. The aim of the present study was to investigate the effect of using calcium salts such as calcium carbonate,<br />calcium chloride and calcium sulphate at different concentrations (0, 1, 3, 5 % w/v) during soaking periods for (30<br />and 60 min) on reducing soluble oxalate and phytic acid in taro corm chips. The experimental results indicated that the<br />optimal conditions were soaking taro corm chips in calcium chloride solution at concentration of 5% for 60 min., since<br />the content of both soluble oxalate and phytic acid were found to decrease from 294.3 to 35.1 mg/100g and from 161.16<br />to 133.68 mg/100g respectively. Calcium carbonate was the lowest effective additive.
Taro corm chips,soluble oxalate,phytic acid,calcium salts,pH
https://ajfs.journals.ekb.eg/article_71656.html
https://ajfs.journals.ekb.eg/article_71656_70fd9b1f83eedfbbfe821f738bf4724c.pdf
The Scientific Society of Food Industries, Alexandria, Egypt.
Alexandria Journal of Food Science and Technology
1687-3920
16
2
2019
12
01
Conversion of inorganic selenium to organic form(s) by Lactobacillus acidophilus
17
24
EN
Mohsen
Abdelaziz
Zommara
0000-0002-1090-5570
Department of Dairy Science, Faculty of Agriculture, Kafrelsheikh University, Kafr El-Sheikh, Egypt
mzommara@agr.kfs.edu.eg
József
Prokisch
University of Debrecen, Faculty of Agricultural and Food Sciences and Environmental Management
Institute of Animal Science, Biotechnology and Nature Conservation, Nanofood Laboratory, Debrecen, Hungary
jprokisch@agr.unideb.hu
10.21608/ajfs.2019.12751.1011
The bioconversion of 2 forms of inorganic selenium namely selenite (SeIV) and selenate (SeVI) to organic<br />form(s) by Lactobacillus acidophilus strain was investigated. The cultured media (MRS) was supplemented with 1,<br />2, 5, 10, 20 ppm of Se in the form of sodium selenite (Na2SeO3, SeIV) or sodium selenate (Na2SeO4, SeVI) and incubated<br />at 37°C up to 24 hr Both Se forms showed no marked effect on the bacterial growth indicating no cytotoxicity<br />at these concentrations. However, the media supplemented with 5, 10 and 20 ppm of Se(IV), but not Se(VI), became<br />reddish after 24 hr of incubation with increasing the red color intense with increasing the Se content in the media. The<br />scanning electron microscope (SEM) investigation clarified the presence of Se-nano particles (SeNPs) in the media.<br />Se speciation of the cultured media supernatant and its corresponding cell fractions using HPLC-ICP-MS technique<br />indicated that the bioconversion rate of Se to organic form(s) was extremely higher in Se(IV) than Se(VI) in both fractions<br />however, the cell fractions contained the highest content. The organic Se gradually increased in both fractions<br />with increasing the media Se content. The inorganic Se was completely bio-converted to organic form(s) without any<br />residual only in the medium contained 1 ppm Se(IV). Our results demonstrate the ability of L. acidophilus to convert<br />Se(IV) but not Se(VI), at a limit concentration of 1 ppm and accumulate organic Se form(s) in the cell fraction. These<br />results confirm the possible bio-production of organic Se enriched fermented dairy products.
bioremediation,organic selenium,inorganic selenium,L. acidophilus,nanoselenium
https://ajfs.journals.ekb.eg/article_71648.html
https://ajfs.journals.ekb.eg/article_71648_76d026e63a139fe2facfefc359d8ff45.pdf
The Scientific Society of Food Industries, Alexandria, Egypt.
Alexandria Journal of Food Science and Technology
1687-3920
16
2
2019
12
01
Prevalence and antibiotic resistance of Staphylococcus aureus isolated from raw milk and dairy products collected from Alexandria, Egypt
25
33
EN
Sahar
Gamal
Abd El Halem
Dairy scince and technolongy department
sahar.gamal500@gmail.com
10.21608/ajfs.2020.15880.1014
The aim of the present study was to determine the prevalence and antibiotic susceptibility of Staphylococcus<br />aureus (S. aureus) isolated from raw milk and some dairy products collected from shops, grocery stores, street vendors<br />at different markets in Alexandria, Egypt and identification of the genes responsible for resistance to some important<br />antibiotics using polymerase chain reaction (PCR) technique. The results of the raw milk and dairy products<br />examined, 22.5% of the samples were positive for S. aureus. It was isolated from 29% of raw milk samples, 12.5%<br />of Kariesh cheese samples, 55% of White cheese samples, 10% of Ras cheese samples, 5.7% of yoghurt samples and<br />24.3% of cream samples. Antimicrobial susceptibility test revealed that all the isolates were susceptible to ciprofloxacin,<br />co-trimoxazole, linezolid, rifampin and vancomycin. Resistance to penicillin G, tetracycline, cefoxitin, chloramphenicol,<br />erythromycin and gentamycin were detected in 91.4%, 65.4%, 42%, 13.6%, 12.3% and 9.9% of the isolates,<br />respectively. The mecA resistance gene was identified in 91.2% of cefoxitin resistant S. aureus isolates, aacA-D was<br />detected in 87.5% gentamycin resistant isolates and ermC gene was detected in 100% of S. aureus isolates showed<br />macrolides resistance whereas ermA could not detected in any of them. The overall prevalence of methicillin resistant<br />S. aureus )MRSA( in the tested raw milk and dairy product samples was 8.6%. The highest methicillin resistant S.<br />aureus prevalence was reported in white cheese samples of 22.5% followed by raw milk, Ras cheese, cream, yoghurt<br />and Kariesh cheese with prevalence of 11%, 7.5% 7.14% 2.9% and 2.5%, respectively
Staphylococcus aureus,Dairy products,prevalence,Antibiotic resistance
https://ajfs.journals.ekb.eg/article_71655.html
https://ajfs.journals.ekb.eg/article_71655_1d47d5ef23d6f669cd14d762cc3d36a3.pdf
The Scientific Society of Food Industries, Alexandria, Egypt.
Alexandria Journal of Food Science and Technology
1687-3920
16
2
2019
12
01
IMPROVEMENT PHESIO-CHEMICAL SENSORY AND MICROBIOLOGICAL CHARACTERS OF SWEET SORGHUM
35
43
EN
soha
Ramadan
khalil
sugar crops research institute., dept sugar technology
sohakhalilscri@gmail.com
samer
mohamed
helmy
Sugar Technol., Res. Dept., Sugar Crops Res. Inst., Agric. Res. Center, Giza, Egypt
allabbodyashraf@yahoo.com
anwar
hamed
sasy
Sugar Technol., Res. Dept., Sugar Crops Res. Inst., Agric. Res. Center, Giza, Egypt
anwarsasy66@gmail.com
10.21608/ajfs.2020.14239.1010
The present work was carried out to evaluate four types of sweet sorghum syrup made from Mn 4080 sweet sorghum<br />variety either alone or with one of three herbal extracts (tumeric, cinnamon and ginger) for the physicochemical,<br />sensory and microbiological properties.<br />The results indicated that sweet sorghum syrup contained cinnamon extract had the highest percentages of sugar<br />profile, tannins, total phenolics, antioxidant activity and minerals (K, Ca and Fe). Moreover, purity and the degree of<br />browning and darkening were increased. Organoleptically, syrup contained cinnamon extract had the highest score<br />in the overall acceptance as compared with the other sorghum syrup types. The results also showed that extracts cinnamon<br />herb played a good role in shelf-life stability during storage period at 25 ± 2°C up to 9 months.<br />The present work suggests that the cinnamon extracts can be used as an antioxidant and to improve the palatability<br />of sorghum syrup.
sweet sorghum syrup,herbs flavor,physico-chemical,sensory,microbial counts
https://ajfs.journals.ekb.eg/article_71640.html
https://ajfs.journals.ekb.eg/article_71640_86e37294fe9675d4bb4e064970e94b13.pdf