Preparation of Mucilage/Protein Products from Flaxseed

摘要

This study aimed at obtaining a functional food ingredient in the form of a high mucilage product from hexane defatted isopropanol-detoxified flaxseed meal, hexane defatted-methanol detoxified flaxseed meal and isopropanol defatted flaxseed meal. The mucilage product was prepared by four methods namely: (1) The coprecipitate method, which gave a mucilage/protein product M1, (2) The modified coprecipitate method that resulted in mucilage/protein product M2, (3) The boiling water method that gave rise to mucilage/protein product M3 and (4) The enzymatic treatment method which led to obtain a mucilage/protein product M4. All mucilage/protein products were free of cyanogenic glycosides. Results indicated that M2 contained the highest content of soluble dietary fiber (mucilage) and little protein. Optimum conditions for the production of M2 include: the use of the modified coprecipitate method at a meal: water ratio of 1:40, a mucilage :ethanol ratio of 1:50 and a temperature of 5°C. The antioxidant activities of the four mucilage protein products were in the following order M2>M1>M3>M4. M2 was chosen for further study. Functional properties of M2 revealed poor wetting ability, poor gelling property, reasonable flowability, oil holding capacity, good emulsifying property, foam stability, excellent water absorption capacity. M2 was then incorporated into tap water at different concentrations to give a functional food product fiber water which was stored for three months. Microbiological examination of the stored fiber water revealed no growth of microorganisms. Sensory evaluation of stored samples indicated that color was not affected, also no significant difference of odor and consistency mean values were detected. On the other hand, the taste and overall acceptability mean values were significantly affected.