Roasting of Navy Beans (Phaseolus vulgaris) by Particle-to-Particle Heat Transfer

Authors


  • Presented at the 41st Annual Meeting of the Institute of Food Technologists, Atlanta, GA. June 7–10. 1981.

  • Supported by Contract No. 59-2481-0-2-001-0 from the United States Department of Agriculture, Science and Education Administration, Washington, DC.

  • Reference to a company and/or product is only for purposes of information and does not imply approval or recommendation of the product to the exclusion of others which may also be suitable.

  • Appreciation is expressed to the Michigan Bean Shippers Association for the donation of navy beans.

ABSTRACT

A rotating chamber dry roaster using pre-heated ceramic beads as heat transfer media was used to roast navy beans. Processing conditions were: beads temperature, 240 and 270°C; bean-to-bead ratio, 1/10 and 1/15 and contact times of 1 and 2 min. Product temperatures achieved ranged from 92–125°C for the eight runs. Heat transfer coefficients varied from 3.6–23.4 W/(m2) (°C). Roasted products showed reduced water-soluble nitrogen content and gel forming capacity, increased water-holding capacity and cold paste viscosities, and no changes in available lysine and degree of starch damage. Residual trypsin inhibitor (TIA) and hemagglutinin activity varied from 92 to 22%, and 48 to 1%, respectively. A correlation was found to exist between nitrogen solubility index and TIA of products. Roasting caused fracture and separation of hulls, and facilitated their removal.

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