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ARS Home » Midwest Area » East Lansing, Michigan » Sugarbeet and Bean Research » Research » Publications at this Location » Publication #314689
Title: Phytohemagglutination Activity in Extruded Dry Bean Powder

Author
item BERRY, MATT - Michigan State University
item Cichy, Karen
item AI, YOUNGFENG - Michigan State University
item NG, PERRY - Michigan State University

Submitted to: Bean Improvement Cooperative Annual Report
Publication Type: Research Notes
Publication Acceptance Date: 2/28/2015
Publication Date: 3/1/2015
Citation: Berry, M., Cichy, K.A., Ai, Y., Ng, P. 2015. Phytohemagglutination Activity in Extruded Dry Bean Powder. Bean Improvement Cooperative Annual Report. 58:1-2.

Interpretive Summary: Cooking is an important requirement prior to bean consumption. Not only does it make beans palatable, but it also inactivates some anti-nutritional components of bean seeds. Lectin is one such component. If consumed raw or undercooked, lectin poisoning can occur. Symptoms of lectin poisoning include vomiting, diarrhea, and abdominal pain. There is interest from food companies to use milled bean powder as an ingredient in snack foods and baked goods and to bypass the cooking in water step, instead cooking via extrusion. The purpose of this study was to test the lectin levels in extruded bean powders of four varieties. Raw milled beans were included as a positive control. Cooked navy and black beans were included as negative controls. The experiment conducted indirectly measures lectin content via phytohemagglutination activity. Extrusion reduced lectins to similar levels of what was present in the cooked samples. Our results suggest that extrusion of beans is a safe way to prepare beans for human consumption.

Technical Abstract: Dry beans are a highly nutritious food. Besides making beans palatable, cooking is required to denature lectin, a protein found in beans. If consumed raw or undercooked, lectin poisoning can occur. Symptoms of lectin poisoning include vomiting, diarrhea, and abdominal pain, and occur within hours of ingestion. Commercial companies have begun to realize the value of beans as an ingredient and some are producing bean powder as a possible alternative to grain flour. Four varieties representing different bean market classes were milled and extruded under different conditions to produce bean powder. Raw milled beans were included as a positive control. Cooked navy and black beans were included as negative controls. The experiment conducted indirectly measures lectin content via phytohemagglutination activity. The highest PHA activity was observed in the raw powder of the black, navy and fuji beans. Extrusion reduced PHA activity to similar levels of what was present in the cooked samples. Previous works suggests that extrusion is a safe method to prepare bean powder. Our results also suggest that extrusion of beans to prepare bean flour is a safe way to prepare beans for human consumption. In addition, recipes that use bean powder involve additional cooking or dilution with other ingredients further reducing active lectin present.