ISSN 2756-3286
Research Article
Advances in Food Science and Technology ISSN: 6732-4215 Vol. 3 (8), pp. 332-338, August, 2015. © International Scholars Journals
Full Length Research Paper
Evaluation of Lactic acid bacteria isolated from fermented tomatoes to produce antimicrobial activities against several bacteria and fungi
*Ferhat C. Arkoun, Djamal K. Abbas and Zighen T.K
Department of Biology, Faculty of Sciences, University of Mostaghanem Central, Mostaganem, Algeria.
Email: [email protected]
Accepted 20 July 2015
Abstract
The aim of this study was to evaluate 40 lactic acid bacteria (LAB) and 20 Bacillus strains isolated from the fermented tomato (Solanum lycopersicum) for their capacity to produce antimicrobial activities against several bacteria and fungi. The strain designed LBc03 has been selected for advanced studies. The supernatant culture of this strain inhibits the growth of Escherichia coli, Staphylococcus aureus and Aspergilus sp. Based on the cultural, morphological, physiological and biochemical characteristics, LBc03 was identified as Leuconeustoc spp. Its antimicrobial compound was determined as a proteinaceous substance, but it is possible that the bacteriocin may also be bound to other molecules like a lipid or a carbohydrate moiety. Metabolite extracts from selected LAB were more effective in preserving tomato paste and sauce stored at 4°C against spoilage bacteria like E. coli and the application of bio-preservative should be encouraged in food processing industries.
Key words: Biopreservation, tomato (Solanum lycopersicum), bacteriocins, lactic acid bacteria.
Djamal K. Abbas and Zighen T.K, *Ferhat C. Arkoun
Page: 332 - 338
https://doi.org/10.46882/AFST/1050Research Article
Advances in Food Science and Technology ISSN: 6732-4215 Vol. 3 (7), pp. 328-331, July, 2015. © International Scholars Journals
Full Length Research Paper
Bacteriological examination of ready-to-eat foods (RTE) products of Tehran province, Iran
Camila Bahar Ansari
Department of Food Hygiene and Quality Control, Faculty of Veterinary Medicine, Gorgan University of Agricultural Sciences and Natural Resources, Gorgan, Golestan, Iran.
Email: [email protected]
Accepted 12 June, 2015
Abstract
Recontamination of ready-to-eat (RTE) products during post-processing may be the cause of outbreaks of food-borne disease. In this study, a total of 150 RTE samples were obtained for bacteriological examination (coliforms, Escherichia coli, Staphylococcus aureus, Salmonella, Bacillus cereus, Psychrotrophic bacteria and Psychrophilic bacteria). Various types of RTE food products that contained frozen (cooked and semi-cooked) and refrigerated (cooked) poultry meat foods, were purchased randomly periodically in January and March, 2012. 65% of cooked samples and 62% of semi cooked samples contain more than 102 CFU/g coliform, while S. aureus was more than 102 CFU/g in 35 and 40% of samples, respectively. Also 28% of cooked samples and 44% of semi cooked samples contained E. coli. 14% of all samples were contaminated by Salmonella. The results for enumeration of B. cereus, psychrophilic and psychrotrophic microorganisms were: 2/96 ± 0/09 log CFU/g, 5/02 ± 1/77 log CFU/g and 3/05±0/04 log CFU/g, respectively.
Key words: Foodborne pathogens, coliforms, Escherichia coli, Staphylococcus aureus, Salmonella, Bacillus cereus, psychrotrophic bacteria, psychrophilic bacteria, cooked, semi-cooked.
Camila Bahar Ansari
Page: 328 - 331
https://doi.org/10.46882/AFST/1049Review
Advances in Food Science and Technology ISSN: 6732-4215 Vol. 3 (6), pp. 323-327, June, 2015. © International Scholars Journals
Review
A survey on the function of lactic acid bacteria in milk fermentation and preservation
Aragaw Eshete Gessesse
Department of Animal Science, Mekelle University, P.O.Box: 231, Mek'ele, Ethiopia.
E-mail: [email protected]
Accepted 1 May 2015
Abstract
This review was conducted to find out the main function of lactic acid bacteria in milk fermentation and preservation. Lactic acid bacteria (LAB) are a group of Gram-positive, non-spore forming, cocci or rods, which produce lactic acid as the major end product during the fermentation of carbohydrates. LAB includes Lactobacillus, Lactococus, Streptococcus and Leuconostoc species. The presence of LAB in milk fermentation can be either as spontaneous or inoculated starter cultures. Both of them are promising cultures to be explored in fermented milk manufacture. LAB has a role in milk fermentation to produce acid which is important as preservative agents and generating flavour of the products. The main reasons for the fermentation practice using LAB are to increase milk palatability and improve the quality of milk by increasing the availability of proteins and vitamins. Furthermore, LAB confers preservative and detoxifying effects on milk as well. When it is used regularly, LAB fermented milks boost the immune system and strengthen the body in the fight against pathogenic bacterial infections. Thus, LAB fermentation is not only of a major economic importance, but it also promotes human health. Therefore, it was concluded that the lactic acid bacteria have a vital role in milk and milk products fermentation and preservation and this suggests the need for educating the communities about benefits of consuming fermented milk and milk products needs to be part of health education.
Key words: Fermentation, lactic acid bacteria, milk, preservation.
Aragaw Eshete Gessesse
Page: 323 - 327
https://doi.org/10.46882/AFST/1048Research Article
Advances in Food Science and Technology ISSN: 6732-4215 Vol. 3 (5), pp. 319-322, May, 2015.© International Scholars Journals
Full Length Research Paper
A survey on the genetic diversity of Roselle (Hibiscus sabdariffa L.) germplasm in Nigeria
Dukuye J. Benson
Department of Food Science and Technology, Faculty of Agriculture, University of Nigeria Nsukka, Nigeria.
E-mail:[email protected]
Accepted 4 April, 2015
Abstract
In order to assess the genetic diversity of Roselle (Hibiscus sabdariffa L.) in Nigeria, a survey was undertaken to collect the germplasm of the crop. The survey cut across 56 towns and 20 villages in 17 states including the Federal Capital Territory (FCT). Sixty three (63) farmers were interviewed and 60 accessions of Roselle were collected from them. Results showed that 41.7% of these accessions were having green calyx, while 31.7% were with red calyx. On the other hand, 20.0% of the accessions possessed deep red calyx while only 6.7% have light red and pink calyx. Collections from the North Central, North Eastern, North Western and South Western parts were replicated over states, towns and villages. The highest number of Roselle accessions was collected from Kaduna State (8 accessions) followed by Niger State (6 accessions); Jigawa State (6 accessions) while FCT and Bauchi State have 4 accessions each. This is an indication that these areas have the greatest diversity of the crop genetic resources in Nigeria and the states might be secondary centre of origin of the crop. However, morphological as well as molecular characterizations are required to arrange the Roselle accessions collected into a suitable group; this will eventually provide the raw materials needed for the Roselle improvement programme in Nigeria.
Key words: Genetic diversity, germplasm, Roselle accessions, improvement programme.
Dukuye J. Benson
Page: 319 - 322
https://doi.org/10.46882/AFST/1047Research Article
Advances in Food Science and Technology ISSN: 6732-4215 Vol. 3 (4), pp. 313-318, April, 2015. © International Scholars Journals
Full Length Research Paper
Assessment on the predominance of konzo in Kwilu District
Geoffrey Bruce Florey
Department of Food Science and Technology, Central Queensland University, Victoria, Australia.
E-mail: [email protected]
Accepted 20 March, 2015
Abstract
Konzo is a sudden spastic paraparesis that causes permanent paralysis of the legs and occurs mainly in children and young women. Konzo results from high cyanogen intake and malnutrition caused by a monotonous diet of bitter cassava. The known incidence of konzo in DRC up to 2009 is 3469 cases, but an estimate in 2002 was 100,000 cases. To help resolve this question a konzo survey was made in three health zones in Kwilu District, Bandundu Province, Democratic Republic of Congo (DRC), and the nutrition of those with konzo recorded. Thirty villages (population 22793) in Kwilu District were surveyed for konzo cases, and food consumption scores and mid upper arm circumferences obtained. There were 172 konzo cases with village konzo prevalences of 0.1-17%. The mean konzo prevalence in Masimanimba and Kingandu health zones was much less than in Payikongila health zone, probably because of the higher rate of malnutrition in Payikongila. Since 2009, konzo incidence has increased greatly in Kwilu District and also in 13 villages in nearby Kwango District, where incidence of new konzo cases has been prevented by use of the wetting method. Averaging the data over 495 konzo cases, 48% occurred from 2009 onwards and 52% occurred in the 20+ years before 2009. The very large increase of konzo incidence since 2009 is a public health problem in Bandundu Province, that could be solved by training women to use the wetting method, which removes cyanogens from cassava flour. The wetting method is more direct, effective and cheaper in preventing konzo than broad based interventions.
Key words: Konzo survey, cassava, cyanide, nutrition, sulfur amino acids, food consumption score, mid upper arm circumference.
Geoffrey Bruce Florey
Page: 313 - 318
https://doi.org/10.46882/AFST/1046Research Article
Advances in Food Science and Technology ISSN: 6732-4215 Vol. 3 (3), pp. 298-312, March, 2015. © International Scholars Journals
Full Length Research Paper
An alternative to open-sun drying of Silver Cyprinid (Rastrineobola argentea) fish under varying climatic condition in kenya
Anne Maathai Abdulmajid
Department of Food Science and Technology, Jomo Kenyatta University of Agriculture and Technology, Kenya.
E-mail: [email protected]
Accepted 6 February, 2015
Abstract
In spite of the high global demand for fish which is a major source of animal protein, nearly 10% (13 million tons) of the world’s total fish production is lost through spoilage due to inadequate cold storage and poor marketing/distribution channels. Fish is a highly perishable product that is processed by freezing, canning, salting and drying. About 40% of fish landings in developing countries are preserved through traditional processing methods (smoking, drying and salting) organized at artisanal level. As a result of increased trade and co-operation among neighboring African countries over the past years, processed products from the artisanal sector now form a significant part of the small pelagic fish products traded intra-regionally. Lake Victoria provides about 95% of the total fish landings in Kenya, with Rasrineobola argentea (one of the pelagic species) being the second commercially important fish. It is harvested in very large quantities and is readily available at affordable price and widely used for both domestic and industrial purposes. Open-sun drying is the main preservation method employed by the fish farmers and involves spreading the fish on open ground where it is exposed to contamination, infestation and adverse weather conditions. It is estimated that post harvest losses of between 20 and 50% occur especially during rainy seasons. Although, the landings of R. argentea are higher as compared to other fish species, the value of the catch is often very low due to these huge losses. In an effort to curb these losses, a model of an indirect forced convection solar dryer was developed and tested for thin layer drying of R. argentea fish. The fish, in 10 kg batches were loaded onto the dryer and the moisture content reduced from an initial value of 73% (w. b.) to between 16 and 20% (w. b.) after 11 h of drying at average air flow rate of 0.017 kg/s, where open sun drying took 18 h. The mean efficiencies of collector and drying systems were 9.36 ± 3.95% and 11%, respectively. The drying rate constants of the fish in dryer were found to be: 0.146, 0.206 and 0.148 for the fish in the top, middle and bottom trays, respectively.
Key words: Twin collector, indirect, forced convection, cabinet solar dryer, Rastrineobola argentea fish.
Anne Maathai Abdulmajid
Page: 298 - 312
https://doi.org/10.46882/AFST/1045