The invention provides a preparation method of
asparagus agar oligosaccharide, and relates to the technical field of
oligosaccharide production. The preparation method comprises the following steps: (1) soaking the
asparagus in salt brine for 3 to 5 hours, and then
drying the
asparagus; (2) pulverizing the asparagus in a
pulverizer and filtering the smashed asparagus to obtain asparagus puree; (3)adding the asparagus puree into water at the
mass ratio of the asparagus puree to the water tobe 1 to (21-26), and heating the mixture at the temperature of 105-115 DEG C for 90-105 min to obtain a water-extracted mixture; (4) carrying out
microwave heating and
agar extraction on the water-extracted mixture to obtain an
agar solution; (5) after cooling, adding a buffer agent and beta-
agarase, heating the mixture to 38-45 DEG C, and carrying out enzymolysis on the mixture for 3-10 h to obtain an asparagus
oligosaccharide solution; and (6)
drying the asparagus oligosaccharide solution to obtainthe asparagus oligosaccharide. According to the invention, the agar is extracted by the process of crushing, heating and
microwave treatment of the asparagus, the extraction rate of the agar is increased and the prepared agar oligosaccharide has high
antioxidant activity and high probiotics activity.