ARS | Publication request: RHEOLOGICAL PROPERTIES OF LESQUERELLA GUM FRACTIONS RECOVERED BY AQUEOUS EXTRACTION

Submitted to: Industrial Crops and Products
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: December 22, 1999
Publication Date: N/A

Interpretive Summary: Lesquerella fendleri is a new crop that contains a natural carbohydrate gum coating the seed. Lesquerella is currently grown for the seed oil but has co-products, such as the gum, which could also be commercialized. We isolated the gum from the seed and obtained physical information that describes the use of the gum as an additive to thicken mixtures or solutions. We proposed a plan to recover the gum from the de-oiled meal following a conventional oil recovery process. Lesquerella gum represents a new product that could be used in edible and industrial formulations.

Technical Abstract: Lesquerella fendleri seeds contain a cross-linked carbohydrate gum with viscoelastic properties that may be used for industrial and edible applications. Laboratory studies compared the rheological behavior of gum isolates obtained from whole seed, defatted hull, and defatted meal fractions. Gum yields and rheological properties were determined for gum isolates from each of these fractions. All gum isolates exhibited positive thixotropy, which provided evidence of structure formation in 1% solutions. Values of storage and loss modulus were reported from oscillatory experiments over an angular frequency range of 0.1 to 100 rad/s using a controlled-stress rheometer. The feasibility of isolating lesquerella seed coat gum as a co-product of the oil recovery process was discussed.