This specification discloses process for obtaining maltodextrin having DE between 17 and 19.9 and the maltodextrins obtained from the process. The disclosed maltodextrins can be provided as a powder or in shelf stable liquid form. The disclose maltodextrins have a polysaccharide profile similar to those observed for prior art maltodextrins, but make maltodextrin solutions having a high solids content, but reduced viscosity compared to prior art maltodextrins, on equivalent solids-in-solution basis. The process combines adds an alpha-amylase and a pullulanase enzyme to a polysaccharide mixture during a saccharification step. The disclosed maltodextrins make solutions at 50° C. and greater than 65% on a solids dry solids basis having a viscosity between 5,000 and 12,000 cP and having a water activity of less than 0.80.

This specification discloses process for obtaining maltodextrin having DE between 17 and 19.9 and the maltodextrins obtained from the process. The disclosed maltodextrins can be provided as a powder or in shelf stable liquid form. The disclose maltodextrins have a polysaccharide profile similar to those observed for prior art maltodextrins, but make maltodextrin solutions having a high solids content, but reduced viscosity compared to prior art maltodextrins, on equivalent solids-in-solution basis. The process combines adds an alpha-amylase and a pullulanase enzyme to a polysaccharide mixture during a saccharification step. The disclosed maltodextrins make solutions at 50° C. and greater than 65% on a solids dry solids basis having a viscosity between 5,000 and 12,000 cP and having a water activity of less than 0.80.

The present invention aims to provide a saccharide composition suitable for a cyclic-tetrasaccharide-containing starch syrup which has low viscosity, low water activity, low coloration property, and low calorie content, and which is unlikely to cause precipitation of crystals of saccharides during storage, and to provide a use of the composition and a production method for the composition. The object is achieved by providing a cyclic-tetrasaccharide-containing saccharide composition having the following characteristics (1) to (3): (1) the saccharide composition includes a branched cyclic tetrasaccharide in addition to the cyclic tetrasaccharide, wherein the content of the cyclic tetrasaccharide with respect to the total solid content of the saccharide composition obtained by allowing glucoamylase and α-glucosidase to act on the above saccharide composition is 38% by mass or higher, on a dry solid basis; (2) the ratio of α-1,4-linked glucose in the total glucose residues constituting the saccharide composition in methylation analysis is over 9% and 15% or lower, and (3) the ratio of α-1,4,6-linked glucose in the total glucose residues constituting the saccharide composition in methylation analysis is less than 6%; and providing a use of the composition and a production method for the composition.

The present invention aims to provide a saccharide composition suitable for a cyclic-tetrasaccharide-containing starch syrup which has low viscosity, low water activity, low coloration property, and low calorie content, and which is unlikely to cause precipitation of crystals of saccharides during storage, and to provide a use of the composition and a production method for the composition. The object is achieved by providing a cyclic-tetrasaccharide-containing saccharide composition having the following characteristics (1) to (3): (1) the saccharide composition includes a branched cyclic tetrasaccharide in addition to the cyclic tetrasaccharide, wherein the content of the cyclic tetrasaccharide with respect to the total solid content of the saccharide composition obtained by allowing glucoamylase and α-glucosidase to act on the above saccharide composition is 38% by mass or higher, on a dry solid basis; (2) the ratio of α-1,4-linked glucose in the total glucose residues constituting the saccharide composition in methylation analysis is over 9% and 15% or lower, and (3) the ratio of α-1,4,6-linked glucose in the total glucose residues constituting the saccharide composition in methylation analysis is less than 6%; and providing a use of the composition and a production method for the composition.

The present disclosure discloses a thermophilic recombinant type II pullulanase and the application thereof, and belongs to the technical field of genetic engineering. The present disclosure obtains a thermophilic recombinant type II pullulanase by heterologously expressing type II pullulanase in Escherichia coli. Its optimum pH is 6.6, it has better pH tolerance under the conditions of pH 5.8-8.0, and its optimum temperature is 95° C. After incubating at 95° C. for 10 h, the remaining enzyme activity is greater than 50%. It can exhibit higher specific enzyme activity under strong reducing conditions. For example, adding DTT to the culture environment can increase the specific enzyme activity of Sumo-Pul.sub.Py by 237.2%. The present disclosure also provides the combined truncation mutant Δ28N+Δ791C of type II pullulanase Sumo-Pul.sub.Py. The specific enzyme activity of the enzyme mutant is 32.18±0.92 U/mg, which is 5.99 times as high as that of the wild-type enzyme, thereby having important industrial application value and potential.

The present invention provides a nanocomposite hydrogel and a preparation method thereof, and relates to the field of nanocomposite materials. The nanocomposite hydrogel is prepared by mixing completely gelatinized short amylose with an aqueous gelatin solution having a mass concentration of 8%-14%, and then cooling. The present invention utilizes the nanoparticles formed by in-situ self-assembly of the short amylose in the aqueous gelatin solution as a reinforcing agent, and the nanoparticles are uniformly distributed in the hydrogel to form a stable crystallization system, such that the prepared nanocomposite hydrogel exhibits optimal mechanical properties in terms of viscoelasticity, hardness, compressive stress, etc. The preparation process of the present invention is green and environmentally friendly, simple and efficient, and can be widely applied to the fields of food, cosmetics and medicine.

The present invention provides a nanocomposite hydrogel and a preparation method thereof, and relates to the field of nanocomposite materials. The nanocomposite hydrogel is prepared by mixing completely gelatinized short amylose with an aqueous gelatin solution having a mass concentration of 8%-14%, and then cooling. The present invention utilizes the nanoparticles formed by in-situ self-assembly of the short amylose in the aqueous gelatin solution as a reinforcing agent, and the nanoparticles are uniformly distributed in the hydrogel to form a stable crystallization system, such that the prepared nanocomposite hydrogel exhibits optimal mechanical properties in terms of viscoelasticity, hardness, compressive stress, etc. The preparation process of the present invention is green and environmentally friendly, simple and efficient, and can be widely applied to the fields of food, cosmetics and medicine.

The present invention provides a system for recovering protein in a production process of an ultrahigh maltose syrup, including a saccharification tank, an enzyme preparation tank, a first plate heat exchanger, a second plate heat exchanger, a plate and frame filter, a buffer tank and a rotary drum filter. The present invention further provides a method of recovering protein by using the system. After the sugar liquid in the saccharification tank is stood, the protein floats at the upper part of the saccharification tank and the lower liquid is clear and transparent and thus the sugar liquid can be directly filtered. When the saccharification tank is discharged, the lower liquid is firstly discharged with the remaining liquid being bottoms containing protein. During a production process, enzymatic hydrolysis is performed for the sugar liquid containing protein before filtration to improve the filtration effect of the sugar liquid. Assisted by the plate and frame filter, protein can be recovered. The present invention improves the economic benefits, reduces the production costs, and thus solves the problem of difficulty in recovering protein in a production process of an ultrahigh maltose syrup.

Embodiments of the present disclosure relate to materials and methods for preparing a clathrate-forming composition comprising a plurality of linear glucomonomer chains of about 15 to about 100 D-glucopyranosyl residues linked by α-1,4 linkages, wherein the linear glucomonomer chains are a product of partial amylolysis of a modified starch substrate and wherein the product is flowable at temperatures within a range of 4-20° C. at about 20% w/v solids content. The present disclosure further describes methods of using the clathrate-forming compositions to form molecular dispersions or clathrates with hydrophobic guest molecules, kits for use in these methods, and molecular dispersions or clathrates obtained from the materials.

Embodiments of the present disclosure relate to materials and methods for preparing a clathrate-forming composition comprising a plurality of linear glucomonomer chains of about 15 to about 100 D-glucopyranosyl residues linked by α-1,4 linkages, wherein the linear glucomonomer chains are a product of partial amylolysis of a modified starch substrate and wherein the product is flowable at temperatures within a range of 4-20° C. at about 20% w/v solids content. The present disclosure further describes methods of using the clathrate-forming compositions to form molecular dispersions or clathrates with hydrophobic guest molecules, kits for use in these methods, and molecular dispersions or clathrates obtained from the materials.