Copyright (c) 2008 All rights reserved. http://works.bepress.com/rogerphilipaidoo Recent documents in Philip R Aidoo en-us Thu, 03 Jan 2008 16:08:47 PST 3600 http://works.bepress.com/rogerphilipaidoo/4 http://works.bepress.com/rogerphilipaidoo/4 Wed, 07 Feb 2007 05:54:43 PST 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 with nixtamalization to maize, it is expected to further improve the functionality, improve nutritional quality and provide an alternative maize-based ingredient. This study was carried out to determine the extent to which fermentation could influence the physico-chemical, functional and textural properties of nixtamalized maize. A 2 x 3 x 3 factorial experimental design with fermentation medium (water, coconut water), fermentation time (0, 24, 48 hours) and blends composition (0:100, 50:50, 100:0 steeped:nixtamalized maize) was performed. The blends were fermented for the specific times and analysed for pH, titratable acidity, water absorption, colour and texture. Traditional maize dough facilitated the fermentation process by acting as a starter culture to produce lower pH and higher acidity in the steeped:nixtamalized maize blends. The fermentation time significantly (p<0.05) influenced the pH, titratable acidity, water absorption capacity, colour and texture of the samples. The pH of all the blends decreased from 6.24 to 4.22 with a corresponding increase in titratable acidity from 0.009 to 0.036 g Lactic/100g sample during fermentation. There was however no significant (p<0.05) difference in the effect of fermentation medium on these indices. The samples with a higher percentage of nixtamalized maize had a deeper yellow colour, that is lower L - value (lightness) and higher b-values (yellowness) than the non- nixtamalized maize and this increased further with fermentation. The texture of the blends of steeped - nixtamalized maize generally decreased with increasing fermentation time for all samples fermented in water as well as in coconut water, however, the texture of the blends of steeped: nixtamalized maize for samples fermented in coconut water had relatively higher but comparable textural values. Maize can therefore be nixtamalized and fermented using both water and coconut water to effectively produce adequate souring or acids resulting in improved physico-chemical, functional and textural quality characteristics required for the processing of traditional fermented maize products. Emmanuel Ohene Afoakwa Food Processing and Quality Control http://works.bepress.com/rogerphilipaidoo/3 http://works.bepress.com/rogerphilipaidoo/3 Wed, 07 Feb 2007 05:54:42 PST 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 with nixtamalization to maize, it is expected to further improve the functionality, improve nutritional quality and provide an alternative maize-based ingredient. This study was carried out to determine the extent to which fermentation could influence the physico-chemical, functional and textural properties of nixtamalized maize. A 2 x 3 x 3 factorial experimental design with fermentation medium (water, coconut water), fermentation time (0, 24, 48 hours) and blends composition (0:100, 50:50, 100:0 steeped:nixtamalized maize) was performed. The blends were fermented for the specific times and analysed for pH, titratable acidity, water absorption, colour and texture. Traditional maize dough facilitated the fermentation process by acting as a starter culture to produce lower pH and higher acidity in the steeped:nixtamalized maize blends. The fermentation time significantly (p<0.05) influenced the pH, titratable acidity, water absorption capacity, colour and texture of the samples. The pH of all the blends decreased from 6.24 to 4.22 with a corresponding increase in titratable acidity from 0.009 to 0.036 g Lactic/100g sample during fermentation. There was however no significant (p<0.05) difference in the effect of fermentation medium on these indices. The samples with a higher percentage of nixtamalized maize had a deeper yellow colour, that is lower L - value (lightness) and higher b-values (yellowness) than the non- nixtamalized maize and this increased further with fermentation. The texture of the blends of steeped - nixtamalized maize generally decreased with increasing fermentation time for all samples fermented in water as well as in coconut water, however, the texture of the blends of steeped: nixtamalized maize for samples fermented in coconut water had relatively higher but comparable textural values. Maize can therefore be nixtamalized and fermented using both water and coconut water to effectively produce adequate souring or acids resulting in improved physico-chemical, functional and textural quality characteristics required for the processing of traditional fermented maize products. Emmanuel Ohene Afoakwa Food Process Engineering http://works.bepress.com/rogerphilipaidoo/2 http://works.bepress.com/rogerphilipaidoo/2 Wed, 07 Feb 2007 05:54:41 PST Spontaneous fermentation of maize produces lactic acids resulting in souring or acidification with associated improvement in taste, flavour and texture of the derived products. When combined with nixtamalization and cowpea fortification, it is expected to improve the nutritional quality and product functionality of maize based foods and as well introduce variety to maize processing. This study was carried out to investigate the changes in souring development, nutritional quality and functional properties during spontaneous fermentation of cowpea-fortified nixtamalized maize. A 2 x 3 x 3 factorial experimental design, with fermentation medium (water, coconut water), fermentation time (0, 24, 48 hours) and cowpea level (0, 15, 30 %) was performed. Nixtamalized maize was prepared by boiling whole maize in 1 % lime solution for 30 minutes, steeped in excess lime, milled into meal and kneaded into a dough using water or coconut water. The blends were fermented for the specific times and analysed for pH, titratable acidity, water absorption capacity, colour, protein and ash. The presence of lime and cowpea influenced the pH, titratable acidity, water absorption, colour, protein and ash content of the fermented cowpea-fortified maize. Addition of cowpea increased most of the studied indices whiles pH of all the blends decreased (6.15-4.45) with a corresponding increase in titratable acidity (0.008-0.045 g/100g lactic acid) with increase in fermentation time. There was however no significant (p<0.05) difference in the effect of fermentation medium on these indices suggesting that coconut water could be used as an alternative fermentation medium for maize dough fermentation without any effect in souring development. Fermentation and cowpea fortification can therefore be used to increase the nutritive value of nixtamalized maize with acceptable souring and product quality characteristics. Emmanuel Ohene Afoakwa Food Processing http://works.bepress.com/rogerphilipaidoo/1 http://works.bepress.com/rogerphilipaidoo/1 Wed, 07 Feb 2007 05:54:39 PST Spontaneous fermentation of maize produces lactic acids resulting in souring or acidification with associated improvement in taste, flavour and texture of the derived products. When combined with nixtamalization and cowpea fortification, it is expected to improve the nutritional quality and product functionality of maize based foods and as well introduce variety to maize processing. This study was carried out to investigate the changes in souring development, nutritional quality and functional properties during spontaneous fermentation of cowpea-fortified nixtamalized maize. A 2 x 3 x 3 factorial experimental design, with fermentation medium (water, coconut water), fermentation time (0, 24, 48 hours) and cowpea level (0, 15, 30 %) was performed. Nixtamalized maize was prepared by boiling whole maize in 1 % lime solution for 30 minutes, steeped in excess lime, milled into meal and kneaded into a dough using water or coconut water. The blends were fermented for the specific times and analysed for pH, titratable acidity, water absorption capacity, colour, protein and ash. The presence of lime and cowpea influenced the pH, titratable acidity, water absorption, colour, protein and ash content of the fermented cowpea-fortified maize. Addition of cowpea increased most of the studied indices whiles pH of all the blends decreased (6.15-4.45) with a corresponding increase in titratable acidity (0.008-0.045 g/100g lactic acid) with increase in fermentation time. There was however no significant (p<0.05) difference in the effect of fermentation medium on these indices suggesting that coconut water could be used as an alternative fermentation medium for maize dough fermentation without any effect in souring development. Fermentation and cowpea fortification can therefore be used to increase the nutritive value of nixtamalized maize with acceptable souring and product quality characteristics. Emmanuel Ohene Afoakwa Food Process Engineering