Increase in Tannin Content of Some Selected Nigerian Vegetables during Blanching and Juicing
Bamidele Adewale Salau *
Department of chemical sciences, College of Natural Sciences, Redeemer’s University, Km. 46 Lagos/Ibadan Expressway, P.M.B. 3005, Redemption City, Mowe, Ogun State, Nigeria.
Kuburat Temitope Odufuwa
Department of Biochemistry, Faculty of Basic Medical Sciences Obafemi Awolowo College of Health Sciences, Olabisi Onabanjo University, Ogun State, Nigeria.
Olumide D. Olukanni
Department of chemical sciences, College of Natural Sciences, Redeemer’s University, Km. 46 Lagos/Ibadan Expressway, P.M.B. 3005, Redemption City, Mowe, Ogun State, Nigeria.
Adeleke K. Atunnise
Department of Biochemistry, Faculty of Basic Medical Sciences Obafemi Awolowo College of Health Sciences, Olabisi Onabanjo University, Ogun State, Nigeria.
Gbenga G. Daramola
Department of chemical sciences, College of Natural Sciences, Redeemer’s University, Km. 46 Lagos/Ibadan Expressway, P.M.B. 3005, Redemption City, Mowe, Ogun State, Nigeria.
*Author to whom correspondence should be addressed.
Abstract
Aims: This study was set to investigate the content of tannin in fresh, blanched vegetables and juiced extracts from the commonly consumed vegetables in South-Western Nigeria.
Place and Duration of Study: Chemical science department, Redeemers University, Nigeria. Research work was done between January and March, 2013.
Methodology: The vegetables were obtained from four different major markets in South West, Nigeria and grouped into three: fresh, blanched, and juiced, using standard laboratory procedures to analyze tannin content.
Results: The results from fresh vegetables showed that Amaranthus viridis has the highest tannin level (30.20±1.05 mg/100g dry weight) while lowest was in Veronia amygdalina (1.02±0.02 mg/100g dry weight). Also, in blanched vegetables Amaranthus viridis has the highest tannin level (46.81 mg/100g dry weight) and lowest was found in Corchorus oliterus (5.05 mg/100g dry weight). In the juiced extract however, Launea taraxacifolia has highest tannin level (735.77 mg/100g dry weight) while lowest was recorded in Celosia argentea (67.18 mg/100g dry weight).
Conclusion: It can be concluded from this study that juicing and blanching substantially increase tannin content in most vegetables.
Keywords: Vegetables, tannin, juicing, blanched