Plant Foods for Human Nutrition

, Volume 37, Issue 2, pp 183–192 | Cite as

Effects of heat on the removal of polyphenols and in vitro protein digestibility of cowpea (Vigna unguiculata (L.) Walp.)

  • Antonio C. Laurena
  • Virgilio V. Garcia
  • Evelyn Mae
  • T. Mendoza


Simple wet heat treatments like simple boiling (atmospheric pressure, 100 °C) and pressurized boiling (higher than 100 °C) reduced the polyphenol content of mature dark red seeds of cowpea (Vigna unguiculata (L.) Walp.) cultivar UPL Cp 3 by 61 to 80% and improved in vitro protein digestibility (IVPD) by 6 to 26%. Pressurized steaming (higher than 100 °C) removed 48 to 83% of the polyphenols but increased IVPD by only 1.1 to 4.2%. Dry heat as exemplified by roasting and microwave treatment inactivated 58 to 71% of the tannins but increased IVPD by only 1%. All the heat treatments were effective in removing/inactivating polyphenols though different responses were observed with the resulting in vitro protein digestibilities.

Key words

cowpea detoxification protein digestibility polyphenols tannins 


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Copyright information

© Martinus Nijhoff Publishers 1987

Authors and Affiliations

  • Antonio C. Laurena
    • 1
  • Virgilio V. Garcia
    • 2
  • Evelyn Mae
  • T. Mendoza
    • 1
  1. 1.Biochemistry Laboratory of the Institute of Plant Breeding, College of Agriculture (CA)University of the Phillipines at Los Baños, (UPLB)LagunaPhilippines
  2. 2.Institute of Food Science and Technologyalso of UPLBPhilippines

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