Up-scaling the traditional processing of akpan for conquering urban consumers

Maize akpan is a homemade fermented beverage, resembling yoghurt, which is sold as street food in Benin in west Africa. The traditional character of the production leads to variations in the product quality, and sometimes, to consumer dissatisfaction. This project aims at upgrading the traditional process of maize akpan, first by controlling the fermentation step using living organisms found in naturally fermented maize starch, and second, by stopping the product acidification after it is made according to a designed process.

Background

Maize is one of the major staple crops in Sub-Saharan Africa. There are several forms in which it is consumed, each deriving from specific, but mainly traditional, processing methods. Many maize-based foods are fermented during production. The final fermented products may be solid foods or beverages. One of the beverages produced in Benin is akpan, a ready-to-drink yoghurt-like product well known and consumed in the country’s urban and rural areas. Akpan is also produced from sorghum or a mixture of maize and sorghum. However, the ethnical and geographical origin of the product confirms the use of fermented maize starch, called “ogi” in Benin, as the original intermediate product. In addition, maize-based akpan is the most preferred by consumers. It is obtained by cooking a portion of the maize ogi to which some non-cooked portion is added, followed by thorough mixing. It has a white colour, aroma of fermented maize product, smooth and creamy texture, and a floury or grainy mouthfeel due to the non-cooked starch granules. Consumers like it either plain with no added ingredient, or added with sugar, milk, ice cubes depending on their preferences. But the quality of akpan varies from a processor to another and even between productions with a same processor, which is linked to the traditional character of the fermentation step. Also, because of the non-cooked fermented starch portion in the product, a continuous acidification is observed that affects its quality and shelf life. Resolving these two problems is the focus of the current project, which combines tools from microbiology, genetics, food technology and quality.

Project description

This research project will address the problems raised above in several steps. To standardize the quality of maize-akpan, we aims at rendering controlled the fermentation of maize starch into ogi by developing a starter culture. For this, a first step will consist in isolation and identification of lactic acid bacteria (LAB) and yeasts, known as fermenting microorganisms in maize products fermentation, from ogi samples produced by traditional processors. Second, a mixed, defined, and autochthonous starter culture will be developed from a selection of the LAB and yeasts isolates, with the goal of standardizing and improving the quality of fermented ogi in the frame of akpan production. To stop the continuous acidification in maize-akpan after it is made, the focus is on developing a dry form of fermented maize starch, which after reconstitution will give a product with similar quality as traditional akpan. Experiments will be realized to determine the best drying and reconstitution conditions using simple drying techniques and minimal processing operations. Further, the acceptability of akpan obtained from the dry fermented starch will be evaluated by product and consumer based sensory tests. Next, the stability of the new products during storage will be evaluated.