Open Access. Powered by Scholars. Published by Universities.®

Social and Behavioral Sciences Commons

Open Access. Powered by Scholars. Published by Universities.®

Plant Sciences

PDF

Selected Works

Institution
Keyword
Publication Year
Publication

Articles 121 - 140 of 140

Full-Text Articles in Social and Behavioral Sciences

Application Of Response Surface Methodology For Studying The Product Characteristics Of Extruded Rice-Cowpea-Groundnut Blends, Emmanuel Asare, Samuel Sefa-Dedeh, Emmanuel Ohene Afoakwa Jul 2004

Application Of Response Surface Methodology For Studying The Product Characteristics Of Extruded Rice-Cowpea-Groundnut Blends, Emmanuel Asare, Samuel Sefa-Dedeh, Emmanuel Ohene Afoakwa

Professor Emmanuel Ohene Afoakwa

Response surface methodology (with central composite rotatable design for k=3 was used to investigate the product properties of extruded rice-cowpea-groundnut blends in a single screw extruder. The combined effect of cowpea (0-20%), groundnut (0-10%), and feed moisture (14-48%) levels were used for formulation of the products. The product moisture, expansion ratio, bulk density and total colour change were studied using standard analytical methods. Well-expanded rice-legume blend extrudates of less bulk density and lower moisture content were produced at low feed moisture. Increasing legume addition affected the various shades of colour in the product. Models developed for the indices gave R2 …


The Microflora Of Fermented Nixtamalized Corn, Samuel Sefa-Dedeh, Beatrice Cornelius, Wisdom Amoa-Awua, Esther Sakyi-Dawson, Emmanuel Ohene Afoakwa Jul 2004

The Microflora Of Fermented Nixtamalized Corn, Samuel Sefa-Dedeh, Beatrice Cornelius, Wisdom Amoa-Awua, Esther Sakyi-Dawson, Emmanuel Ohene Afoakwa

Professor Emmanuel Ohene Afoakwa

Nixtamalization is a traditional process that improves the nutritional quality of corn. To provide a means of utilizing the nutritional benefits of nixtamalized corn and improve product acceptability, lactic acid fermentation was applied. The objective of the study was to study the microbial profile and establish the important lactobacilli of fermenting nixtamalized corn dough. Two batches of cleaned whole corn were subjected to the process of nixtamalization, using two concentrations of lime (0.5 or 1.0%), milled, made into a dough (50% moisture) and fermented spontaneously for 72 h. A control sample was prepared without alkaline treatment. pH and titratable acidity …


Effects Of Cowpea Fortification, Dehydration Method And Storage Time On Some Quality Characteristics Of Maize-Based Traditional Weaning Foods., Emmanuel Ohene Afoakwa, Samuel Sefa-Dedeh, Esther Sakyi-Dawson Jun 2004

Effects Of Cowpea Fortification, Dehydration Method And Storage Time On Some Quality Characteristics Of Maize-Based Traditional Weaning Foods., Emmanuel Ohene Afoakwa, Samuel Sefa-Dedeh, Esther Sakyi-Dawson

Professor Emmanuel Ohene Afoakwa

Fortification of cereal-based traditional foods with legume protein can improve their nutritional value. It is, however, important to find out the extent to which the addition of cowpea affects the desirable quality characteristics of traditional weaning foods prepared from fermented maize and also to assess the effect of dehydration method and storage time on the chemical, physico-chemical and functional properties of the products. A 3 x 2 x 4 factorial experiment with cowpea level, drying method and storage time as the respective variables was done. The traditional weaning food was prepared by steeping maize in water for 24 hours, mixed …


Food Based Approaches For A Healthy Nutrition In Africa, Mamoudou Hama Dicko May 2004

Food Based Approaches For A Healthy Nutrition In Africa, Mamoudou Hama Dicko

Pr. Mamoudou H. DICKO, PhD

The latest estimates of the FAO demonstrate the problems of the fight against hunger. These problems are manifested by the ever-increasing number of chronically undernourished people worldwide. Their numbers during the 1999-2001 period were estimated at about 840 million of which 798 million live in developing countries. Sub-Saharan Africa alone represented 198 million of those. In this part of Africa the prevalence of undernourishment ranges from 5-34%, causing growth retardation and insufficient weight gain among one third of the children under five years of age and resulting in a mortality of 5-15% among these children. Malnutrition resulting from undernourishment is …


Effect Of Nixtamalization On The Chemical And Functional Properties Of Maize, Samuel Sefa-Dedeh, Beatrice Cornelius, Emmanuel Ohene Afoakwa Mar 2004

Effect Of Nixtamalization On The Chemical And Functional Properties Of Maize, Samuel Sefa-Dedeh, Beatrice Cornelius, Emmanuel Ohene Afoakwa

Professor Emmanuel Ohene Afoakwa

The high utilization and consumption levels of maize in developing countries calls for investigations into new methods of processing to help introduce variety as well as improve the functionality and nutrient quality of maize-based foods. This study was carried out to determine the effect of nixtamalization on the chemical and functional characteristics of maize. A 2X4 factorial experimental design with cooking time (0, 30 min) and lime concentration (0, 0.33, 0.5 and 1.0%) was performed. Chemical composition (moisture, protein and ash), pH, titratable acidity, water absorption, colour, cooked paste viscosity and texture were determined using standard methods. The cooking time …


Quelques Conseils À Nos Nouveau Diplomés, Fathi Habashi Jun 2003

Quelques Conseils À Nos Nouveau Diplomés, Fathi Habashi

Fathi Habashi

An advice, the old wise man Polonius offered to the young Hamlet was “Neither a borrower, nor a lender be”, may be no longer pertinent. Some more relevant advices are offered to new graduates of the twentieth century. Available in English, French, and Spanish


Effect Of Fermentation On The Quality Characteristics Of Nixtamalized Corn, Emmanuel Ohene Afoakwa, Samuel Sefa-Dedeh, Beatrice Cornelius Apr 2003

Effect Of Fermentation On The Quality Characteristics Of Nixtamalized Corn, Emmanuel Ohene Afoakwa, Samuel Sefa-Dedeh, Beatrice Cornelius

Professor Emmanuel Ohene Afoakwa

Spontaneous lactic acid fermentation is an important process in cereal processing. It is applied to develop and enhance taste and flavour, modify texture and improve the microbial safety of foods. When applied to nixtamalized corn mixed with traditional steeped corn it is expected to further improve the functionality, improve nutritional quality and provide an alternative corn-based ingredient. The objective of this study was to investigate the chemical and functional properties of fermented blends of steeped and nixtamalized corn. A 3_5 factorial experimental design with fermentation time (0, 24, 48 h) and blends composition (0:100, 25:75, 50:50, 75:25, 100:0 steeped:nixtamalized corn) …


From Alchemy To Atomic Bombs. Book Review By George Kauffman, Fathi Habashi Jan 2003

From Alchemy To Atomic Bombs. Book Review By George Kauffman, Fathi Habashi

Fathi Habashi

Review of the book "From Alchemy to Atomic Bombs" by Fathi Habashi published by Métallurgie Extractive Québec. The review is written by Professor George Kauffman at California State University, Fresno.


Viscoelastic Properties And Changes In Pasting Characteristics Of Trifoliate Yam (Dioscorea Dumetorum) Starch After Harvest, Emmanuel Ohene Afoakwa, Samuel Sefa-Dedeh Sep 2002

Viscoelastic Properties And Changes In Pasting Characteristics Of Trifoliate Yam (Dioscorea Dumetorum) Starch After Harvest, Emmanuel Ohene Afoakwa, Samuel Sefa-Dedeh

Professor Emmanuel Ohene Afoakwa

Studies were conducted on the viscoelastic properties, as well as the changes in pasting characteristics, of trifoliate yam, Dioscorea dumetorum, starch during post-harvest hardening of the tubers. A 3x4 factorial experiment with blanching treatment time (0, 15 and 30 s) and storage time (0, 12, 24 and 36 h) as the respective variables was performed. The samples were evaluated for pasting temperature, viscosity at 95 _C, viscosity at 95 _C-Hold, viscosity at 50 _C and viscosity at 50 _C-Hold, as well as their changes during storage of the tubers, to determine the starch behaviour of the D. dumetorum tubers during …


Textural And Microstructural Changes Associated With Post-Harvest Hardening Of Trifoliate Yam (Dioscorea Dumetorum) Pax Tubers, Emmanuel Ohene Afoakwa, Samuel Sefa-Dedeh Aug 2002

Textural And Microstructural Changes Associated With Post-Harvest Hardening Of Trifoliate Yam (Dioscorea Dumetorum) Pax Tubers, Emmanuel Ohene Afoakwa, Samuel Sefa-Dedeh

Professor Emmanuel Ohene Afoakwa

The textural and microstructural changes associated with the post-harvest hardening phenomenon of Dioscorea dumetorum tubers were studied to determine how texture relates to microstructure during the hardening process. A 2x2x4 factorial experiment with sample treatment,storage conditions and storage time as variables was performed. The tubers were harvested,matured and stored under prevailing tropical ambient conditions (28 _C) and cold room conditions (4 _C) for the study. All the samples were evaluated for their hardness (peak force) and adhesiveness (curve areas). Starch microscopy was done on the freshly harvested tubers,hardened tubers and tubers stored under low temperature conditions (4 _C) during the …


Changes In Cell Wall Constituents And Mechanical Properties During Post-Harvest Hardening Of Trifoliate Yam Dioscorea Dumetorum (Kunth) Pax Tubers, Emmanuel Ohene Afoakwa, Samuel Sefa-Dedeh Jul 2002

Changes In Cell Wall Constituents And Mechanical Properties During Post-Harvest Hardening Of Trifoliate Yam Dioscorea Dumetorum (Kunth) Pax Tubers, Emmanuel Ohene Afoakwa, Samuel Sefa-Dedeh

Professor Emmanuel Ohene Afoakwa

In an attempt to investigate the changes leading to the rapid post-harvest hardening of the white cultivars of Dioscorea dumetorum tubers, alterations in the plant cell wall constituents and mechanical properties of the tubers were monitored. A 4x2 factorial experiment with storage time (0, 24, 48 and 72 h) and storage conditions [cold room (4 _C, 85–100% RH) and tropical ambient (28 _C, 62–100% RH)] as variables were performed. Harvested tubers were stored for 24, 48 and 72 h under 4 and 28 _C. Changes in mechanical properties, acid and neutral detergent fibres, lignin, cellulose and hemicellulose contents were monitored. …


Changes In Rheological Properties And Amylase Activities Of Trifoliate Yam, Dioscorea Dumetorum, Starch After Harvest, Emmanuel Ohene Afoakwa, Samuel Sefa-Dedeh May 2002

Changes In Rheological Properties And Amylase Activities Of Trifoliate Yam, Dioscorea Dumetorum, Starch After Harvest, Emmanuel Ohene Afoakwa, Samuel Sefa-Dedeh

Professor Emmanuel Ohene Afoakwa

Changes in rheological properties and amylase activities occurring in trifoliate yam, Dioscorea dumetorum, starch after harvest were investigated. Trifoliate yam tubers were harvested and stored under tropical ambient (28 _C) and cold room conditions (4 _C) for 12, 24 and 36 h. The D. dumetorum starches were extracted from the tubers under study and samples were evaluated for changes in their rheological properties (paste characteristics) during storage and to study the action of amylases on D. dumetorum starch after harvesting. The post-harvest activities of a and b-amylases were also studied to evaluate their rate of action on D. dumetorum starch. …


Biochemical And Textural Changes In Trifoliate Yam Dioscorea Dumetorum Tubers After Harvest, Emmanuel Ohene Afoakwa, Samuel Sefa-Dedeh May 2002

Biochemical And Textural Changes In Trifoliate Yam Dioscorea Dumetorum Tubers After Harvest, Emmanuel Ohene Afoakwa, Samuel Sefa-Dedeh

Professor Emmanuel Ohene Afoakwa

Biochemical and textural changes were investigated in trifoliate yam Dioscorea dumetorum tubers, after harvest, in an attempt to study the chemical and physical changes associated with the raw and cooked tubers and how these relate to the hardening phenomenon of the tubers after harvest. A 2x2x3x4 factorial experiment, with cultivar, storage condition, treatment and storage time as their respective variables, was done. Samples were analysed for moisture, starch, reducing sugars, alcohol-soluble sugars, acid and neutral detergent fibre, cellulose, hemicellulose and lignin. The Warner–Bratzler test cell was used in a TA.XT2 Texture Analyser to measure the hardness of cooked tubers. The …


Η Πανίδα Και Η Χλωρίδα Στην Προϊστορική Κύπρο, Anastasia Tsaliki Dec 2001

Η Πανίδα Και Η Χλωρίδα Στην Προϊστορική Κύπρο, Anastasia Tsaliki

Dr Anastasia Tsaliki, PhD

No abstract provided.


Influence Of Fermentation And Cowpea Steaming On Some Quality Characteristics Of Maize-Cowpea Blends, Samuel Sefa-Dedeh, Yvonne Kluvitse, Emmanuel Ohene Afoakwa Jul 2001

Influence Of Fermentation And Cowpea Steaming On Some Quality Characteristics Of Maize-Cowpea Blends, Samuel Sefa-Dedeh, Yvonne Kluvitse, Emmanuel Ohene Afoakwa

Professor Emmanuel Ohene Afoakwa

Fermentation and cowpea steaming can be used to improve the protein quality and quantity of fermented maize dough. In the production of maize-cowpea blends, it is important that the quality characteristics are evaluated to determine their functionality in the products. A 5x4x2x2 factorial experiment with cowpea level, fermentation time, cowpea steaming time and fermentation method as the variable was performed. The cowpeas were dehulled, steamed, dried at 65EC for 24 hours and milled into flours. Maize was soaked in water (18 hours), drained and milled into flour. The maize-cowpea blends were made into a 50% moisture dough, fermented for the …


Chemical Composition And Quality Changes Occurring In Dioscorea Dumetorum Pax Tubers After Harvest, Emmanuel Ohene Afoakwa, Samuel Sefa-Dedeh Mar 2001

Chemical Composition And Quality Changes Occurring In Dioscorea Dumetorum Pax Tubers After Harvest, Emmanuel Ohene Afoakwa, Samuel Sefa-Dedeh

Professor Emmanuel Ohene Afoakwa

Studies were conducted on the chemical composition, as well as the biochemical and textural changes, occurring during storage of two cultivars of Dioscorea dumetorum yam tubers. The tubers were harvested and stored under tropical ambient (28_C) and cold room conditions (4_C) for 24, 48 and 72 h. The samples were evaluated for moisture, starch, sugars, fibres and textural properties. Chemical analysis showed no significant differences between the means obtained for moisture, ash, protein, fibre, fat, carbohydrate, calcium, phosphorus, iron, vitamin A and vitamin C contents of the cultivars (white and yellow) studied. During storage, moisture contents decreased by approximately 6–10% …


A Memorable Meeting, February 1994, Fathi Habashi Feb 1994

A Memorable Meeting, February 1994, Fathi Habashi

Fathi Habashi

Decision taken at the Steering Committee Meeting of the International Mineral Processing Congress in San Francisco February 1994 to name the IMPC Award.


Hidrometalurjide Yeni, Fathi Habashi Jan 1979

Hidrometalurjide Yeni, Fathi Habashi

Fathi Habashi

Turkish translation of F. Habashi, “Recent Advances in Hydrometallurgy,” Proceedings International Mineral Processing Congress, Warsaw, 1979, edited by J. Laskowski, published by Elsevier, pp. 902–935


Progress In Extractive Metallurgy, Volume 1. Review By G.N. Dobrokhotov, Fathi Habashi Jan 1975

Progress In Extractive Metallurgy, Volume 1. Review By G.N. Dobrokhotov, Fathi Habashi

Fathi Habashi

Review of the first volume of Progress in Extractive Metallurgy edited by Fathi Habashi and published by Gordon & Breach in New York in 1975. The review was written by Professor Dobrokhotov at the Leningrad Mining Institute.


Laotian Agricultural Statistics, Joel Halpern Apr 1961

Laotian Agricultural Statistics, Joel Halpern

Joel M. Halpern

No abstract provided.