NL8302229A - Potato hydrolysate prepn. - by simultaneous enzymatic liquefaction of starch and coagulation of protein - Google Patents

Abstract

Potato hydrolysate is prepd. by grinding potatoes and subjecting the ground material, in presence of an alpha-amylase, opt. after partial recovery of the starch, to simultaneous enzymatic liquefaction of the starch and heat coagulation of the potato protein until a dextrose equiv. of 5-30 has been reached.

Description

A. * VO 4943

Title: Process for preparing potato hydrolyzate material and a product obtained through the process.

The invention relates to a process for preparing potato hydrolyzate material and a product obtained through the process.

By R.S. Moreton is described in J. Appl. Bact., 1978, pp. 373-382, describes a process in which potato waste material, which may come from the manufacture of, for example, French fries or puree powder, is mechanically homogenized and subsequently liquefied with the aid of the enzyme α-amylase. Glucoamylase is then allowed to act on the resulting material for 4-30 hours. The material is then centrifuged. The liquid phase obtained thereby is suitable as a fermentation substrate.

A.M. Al Taweel et al. In Moo-Young, M. and C.V. Robinson, Adv. Biotechnology (Proc. Int. Ferment. Symp.), 6 th, 1980 (Publ. 1981), 2, p. 153-160 describe a process in which potatoes are hydrolyzed by a continuous enzymatic process (as described by Aschengreen et al. In Die Starke, 1979, pp. 64-66). This process includes the steps of: liquefying the starch by heating a starch + water suspension in the presence of α-amylase in a jet cooker to 105 ° C; maintain this temperature for 20 minutes; subject the obtained material to further liquefaction to DE 5-25 (95 ° C; α-amylase; 1-2 hours) and finally subject the liquefied product to further hydrolysis to glucose syrup, dextrose, isomerosis, etc.

The object of the invention is an improved method for preparing potato hydrolyzate material.

According to the invention, the object set in the above paragraph is achieved by subjecting potatoes and the potato ground meal, with or without partial recovery of the starch content therefrom, in the presence of an α-amylase to a simultaneous enzymatic liquefaction of the starch and thermal coagulation of the potato protein 8302229-2- until a product with a dextrose equivalent (DE) of 5-30 is obtained.

Essential in the method according to the invention is the simultaneous occurrence of the enzymatic liquefaction of the starch and the coagulation of the protein.

The product obtained in the thermal-enzymatic treatment of the potato mash can be further processed, subjected to a separating operation to separate a solid phase, consisting of potato fibers and coagulated potato protein, after which the liquid phase can continue are processed. To this end, this liquid phase can be subjected to a drying operation; in particular can be spray dried or roll dried.

It is also possible to subject the liquid phase remaining after separation of the solid phase to a sugar reaction using α-amylase, S-amylase, isomerase, glucoamylase and / or a branching enzyme, whereby a product of varying composition is added to sugars ( glucose, maltose, fructose and higher sugars) can be obtained. Dextrose can be prepared from the product sweetened by glucoamylase by crystallization. According to another elaboration of the process according to the invention, the product obtained in the thermo-enzymatic treatment of the potato grind can first be subjected to the action of decaying enzymes and then separating solid phase, consisting of earth pile fibers and coagulated protein. It has been found that by working in this way the separation of the protein-fiber mass is facilitated.

One or more other enzymes for the hydrolysis of other potato constituents, in particular protein, fat, pectin, cellulose, and / or hemicellulose hydrolyzing enzymes, may be added before, during or after the thermal-enzymatic treatment, It is thus achieved that the C / N ratio in the end products can be changed. Also, these operations can contribute to a better workability (separation by decanting and centrifugation or filtration) of the solid phase, i.e. the undissolved components.

8302229 -3-

For the preparation of the potato hydrolyzate material according to the invention it is possible to start from whole potatoes, but also from potato waste material or potato chips that become available from the French fries industry and the mashed potato powder industry.

Another raw material for the method according to the invention is the material which remains after a part of the starch content in the potato, for example 5b-802, has been recovered from the potato as native pure starch.

The method according to the invention relates to a simple and environmentally friendly process in which all components of the potato can be obtained or recovered in a relatively simple manner. be utilized. No potato amniotic fluid ends up in the wastewater.

The products obtainable by the method according to the invention can be used in various sectors. For example, the potato hydrolysates to be prepared are suitable for the fermentative preparation of organic acids, amino acids, antibiotics, alcoholic beverages, enzymes, vitamin preparation, microbial polysaccharides, yeast, "single cell protein", alcohols and starter cultures, for example lactic acid starter concentrates . In addition, these products can be used in the foundry sector, in feed materials and as plasticizers.

The egg twit / fiber cake obtained as a by-product can be used as such in, for example, animal feeds. However, the wet product can also be processed by ensilation or drying, for example by pneumatic drying.

The invention is further illustrated by the examples below.

Example I

Potatoes were stripped of stones, foliage and straw and then washed. After this, grinding of the potatoes took place using a grater with the addition of 500 ppm. NaHSO-j. The ground material was collected in a stirred tank. The mass thus obtained was heated to 110 ° C by direct steam injection. for about 1 minute, after which atmospheric flash was performed. The slurry was pumped into a stirred tank, at a constant temperature of 80 ° C. ruled. After adjusting the pH to 5.9, α-amylase (0.10 ¾ Thermamyl 120 L from NOVO) was added. The enzymatic liquefaction of the starch was continued until a Dextrose Equivalent (D.E.) of 25 was reached. The undissolved protein and fiber components 5 were subsequently removed with the aid of a decanter (Type Flottweg ZIL) and then dried. The remaining solution was cooled to 60 ° C. and the pH was adjusted to 4.5 with a 30¾ HCl solution. Then 0.25¾ glucoamylase (AMG 200 L from NOVO) was added. After 24 hours of reaction, the D.E. 90. The insolubles formed during the sugar phase 10 were removed with a filter press. The clear liquid was evaporated to a dry matter content of 60¾.

EXAMPLE II

To a ground potato slurry, obtained according to Example I, α-amylase (0.1¾ Thermamyl 120 L from NOVO) was added. Thereafter, direct steam injection took place at a constant temperature of 95 ° C.

for about 1 minute. The low viscosity mass was then subjected to a flow with α-amylase to a D.E. of 25. The undissolved components were decanted according to Example I. The clear liquid was evaporated to 50¾ dry matter and then spray dried.

20 The final product contained 8¾ moisture.

EXAMPLE III

According to Example II, potatoes were ground and the starch present in the resulting slurry was liquefied to a D.E. from 25. De to 60 ° C. cooled mass was adjusted to pH 4.5 with a 30% HCl solution, then 0.25% glucoamylase (AMG 200 L from NOVO) was added. After 24 hours of reaction, the undissolved protein and fiber components were separated with a decanter and a filter press and then dried. The residual glucose solution was evaporated to a dry matter content of 60%. EXAMPLE IV

The sugared mass obtained according to example III was de-dissolved from an undissolved constituents by a membrane pressure filter press (Type Lasta press). The press cake thus obtained contained 60% moisture.

EXAMPLE V

The glucose solution, obtained according to Example III, was evaporated to 7522 dry matter 8302229 '-5- and transferred to a tank at 46 ° C. was set and provided with a ribbon agitator. Glucose monohydrate crystals (10% dry matter) were added to the syrup. The temperature was then reduced in a linear fashion from 5 to 30 ° C over 48 hours. The crystal mass formed was transferred to a centrifuge, separating the crystals from the mother liquor. The crystals were then washed with water and then dried to 9% moisture. The purity of the glucose monohydrate crystals was 99.1%.

8302229

Claims (10)

4 -6-% + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 1. Process for preparing potato hydrolyzate material by grinding potatoes and the potato grind, whether or not after partial recovery of the starch content therefrom, in the presence of an α-amylase, to a simultaneous enzymatic liquefaction of the starch and thermal coagulation of the potato protein until a dextrose equivalent of 5-30 is reached. 2. Process according to claim 1, characterized in that the product obtained in the thermal-enzymatic treatment of the potato grind is subjected to a separation operation to separate a solid phase, consisting of potato fibers and coagulated potato protein, and the liquid phase further processed. Method according to claim 2, characterized in that the liquid phase is subjected to a drying operation, 4. A method according to claim 3, characterized in that the liquid phase is spray-dried or roll-dried. 5. Process according to claim 2, characterized in that the liquid phase is subjected to a sugaring reaction using α-amylase, s-amylase, isomerase, glucoamylase and / or a branching enzyme, the process according to claim 5, with the characterized in that dextrose is prepared from the sugar reaction product by crystallization, 7. Process according to claim 1, characterized in that the product obtained in the thermal-enzymatic treatment of the potato grind is first subjected to the action of sugaring enzymes and then the solid phase, consisting of potato fibers and coagulated protein. , separates, 8. Process according to claim 1, characterized in that before, during or after the thermal-enzymatic treatment an 8302229 * 7 * -7- or more other enzymes are added for the hydrolysis of other potato components. 9. Process according to claim 8, characterized in that fat, protein, pectin, cellulose, and / or lever of lulose hydrolysing enzymes are added. 10. Product obtained by applying the method according to claims 1-9. 8302229