Effect of Liquid and Solid Fermentation on Mineral and Amino Acid Contents of Kersting’s Groundnut (Macrotyloma geocarpum)

Aim: The research aimed to reveal the effect of liquid and solid fermentation on the mineral and amino acid contents of Kersting’s groundnut (Macrotyloma geocarpum).

Design of the Study: A comparative effect of liquid and solid fermentation on the mineral and amino acid contents was evaluated.

Place and Duration of Study: Department of Microbiology and Central Science Laboratory, Federal University of Technology, Akure, Nigeria from June 2013 to April 2014.

Methodology: The seed of Kersting’s groundnut were de-husked and subjected to liquid and solid fermentation using standard methods. The titratable acidity (TTA), Mineral and Amino acid contents (essential and non-essential) of the fermenting samples were accessed every 24hrs during fermentation.

Results: TTA decreased (P=.05) from 0.035 at 0hr to 0.025 mg lactic acid/g at 72hrs of both liquid and solid fermentation. TTA decreased significantly (P=.05) as the fermentation time increased. Potassium (K) content decrease significantly (P=.05) from 300.83±0.11 mg/100 g at 0hr to 217.60±0.07 and 289.26±0.15 mg/100 g at 72hrs of liquid and solid fermentation respectively. Magnesium content reduced significantly (P=.05) from 18.65±0.03 mg/100 g at 0hr to 6.93±0.01 and 7.32±0.04 mg/100 g after 24hrs of liquid and solid fermentation respectively. The value was observed to increase significantly (P=.05) to 15.24±0.60 mg/100 g and 24.27±0.03 mg/100 g after 72hrs of both liquid and solid fermentation respectively. Copper was observed to be absent in the groundnut. A total of 17 amino acids were analysed in the groundnut. Leucine was found to be the most abundant essential amino acid with a value of 7.19±0.00 g/100g protein while Glutamic was the most abundant non-essential amino acid with a value of 15.84±0.01 g/100 g protein. The total essential amino acid (TEAA) ranges from 46.39% to 46.85% of the total amino acid (%TAA).

Conclusion: The study revealed variation in the mineral contents has the fermentation time increased. Amino acid content was observed to increase significantly after 24 and 48hrs of liquid and solid fermentation respectively.