GB2194795A

GB2194795A - Green malt

Info

Publication number: GB2194795A
Application number: GB08619163A
Authority: GB
Inventors: Ian Macartney
Original assignee: PORTGORDON MALTINGS Ltd
Current assignee: PORTGORDON MALTINGS Ltd
Priority date: 1986-08-06
Filing date: 1986-08-06
Publication date: 1988-03-16
Also published as: GB8619163D0

Abstract

Green malt will deteriorate during storage and/or transport if not kiln dried. Kiln drying tends to impair the enzymic activity of the malt. A green malt slurry is provided in which the pH is maintained at or near the pH of unslurried malt, generally above pH 5. The slurried malt does not deteriorate during transport and/or storage and the enzymic activity of the malt is not affected. The pH may be maintained by keeping the green malt slurry at a temperature not exceeding 10 DEG C or by the additions of chemicals e.g. potassium metabisulphite. The green malt may be produced from barley, wheat or rye.

Description

SPECIFICATION Green malt This invention relates to green malt.

Malt produced by maltsters for use by others, for example by whisky distillers is dried in a kiln in order to stabilise the malt so that it will not deteriorate during storage and transport. Green malt not so treated may be attacked by micro organisms causing the malt to putrify and also affecting enzymes in the malt. One of the disadvantages of the kilning process, however, is that the enzymic activity of the malt is diminished. The present invention has been made from a consideration of this problem.

According to the invention there is provided green malt formed as an aqueous slurry having a pH (maintained) at or near the value of the green malt.

The maintenance of the pH at the required level, generally but not always above 5.0, is preferabiy brought about by keeping the slurry at a temperature not exceeding 10.0 C preferably not exceeding 5.0 C. The slurry may be formed with cooled liquid, by adding a coolant such as ice or solid carbon dioxide to the malt prior to formation of the slurry, by chilling the malt itself prior to formation of the slurry, by chilling the slurry or a combination thereof.

Another way of maintaining the pH at the required level comprises chemical treatment for example by the addition of a stabiliser such as sodium metabisulphite or formaldehyde. If desired chemical treatment can be combined with cooling treatment.

Although green malt is normally produced from barley it is within the invention to use green malt produced from any grain, for example, wheat, rye and the like. The green malt may be comminuted prior to formation of the slurry. The product in this form may be required for end users who are not able to handle and mill green malt.

If desired the slurry, particularly slurry formed from comminuted malt, may be separated out into liquid and solid phases. Many of the enzymes in the malt are soluble so that the liquid phase constitutes a product which can be used for example by a distiller. The separated solids can be used as an animal feed. A separated liquid phase would still require to have its pH maintained at or near that of the green malt by cooling and/or chemical treatment for storage and/or transport.

The slurry concentration is preferably arranged with as high a solids content as possible. The limit generally being such that the solids will remain in suspension and the slurry can still be pumped. If the solids content is too low the material is uneconomic to transport and the slurry may separate out. The preferred concentration range is from 20 to 50% by weight of solids the particularly preferred concentration within that range being about 25 to 35to.

The following examples further illustrate the invention reference also being made to the accompanying drawings.

EXAMPLE 1 Green malt prepared, for example, by germinating grain which has been steeped in water until a moisture content of approximately 44% was attained. Germination times were in the order of 3-5 days. The green malt was milled; 2 parts green malt were mixed with 3 parts water, giving a slurry of approximately 24% dry weight. The slurries were chilled to 5, 10, 15 and 20 deg C. The latter is effectively an ambient temperature control. The pH of the slurry was measured at intervals. It can be seen from Fig. 1 that at temperatures of 20"C and 15"C there is rapid fall in pH within 24 hours, but 10 C slows this fall, and 5"C is effective in maintaining the pH above 5.0 for up to 48 hours.

EXAMPLE 2 The same system as in Example 1 was used with the addition of potassium metabisul phite-equivalent to 200 ppm sulphur dioxide.

The results are shown in Fig: 2. The pH drop was less in this case.

The ultimate criterion for the end user of the product according to the invention is that it should ferment with the required "spirit yield". The fermentability of the product is not affected by the treatment of the slurry to maintain the required pH level.

The invention is not confined to the specific embodiments described. Many variations and modifications are possible.

1. Green malt in the form of an aqueous slurry having a pH maintained at or near the value of green malt.

2. Green malt slurry as claimed in Claim 1 wherein the pH is maintained at the desired level by keeping the slurry at a temperature not exceeding 10 C.

3. Green malt slurry as claimed in Claim 2, wherein the pH is maintained at the desired level by keeping the slurry at a temperature not exceeding 5"C.

4. Green malt slurry as claimed in any preceding claim, wherein the slurry is formed with cooled liquid.

5. Green malt slurry as claimed in any preceding claim wherein coolant is added to the malt before formation of the slurry.

6. Green malt slurry as claimed in any preceding claim, wherein the malt is chilled before formation of the slurry.

7. Green malt slurry as claimed in any preceding claim, wherein the slurry is chilled.

8. Green malt slurry as claimed in any preceding claim, wherein the pH of the slurry is

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Green malt This invention relates to green malt. Malt produced by maltsters for use by others, for example by whisky distillers is dried in a kiln in order to stabilise the malt so that it will not deteriorate during storage and transport. Green malt not so treated may be attacked by micro organisms causing the malt to putrify and also affecting enzymes in the malt. One of the disadvantages of the kilning process, however, is that the enzymic activity of the malt is diminished. The present invention has been made from a consideration of this problem. According to the invention there is provided green malt formed as an aqueous slurry having a pH (maintained) at or near the value of the green malt. The maintenance of the pH at the required level, generally but not always above 5.0, is preferabiy brought about by keeping the slurry at a temperature not exceeding 10.0 C preferably not exceeding 5.0 C. The slurry may be formed with cooled liquid, by adding a coolant such as ice or solid carbon dioxide to the malt prior to formation of the slurry, by chilling the malt itself prior to formation of the slurry, by chilling the slurry or a combination thereof. Another way of maintaining the pH at the required level comprises chemical treatment for example by the addition of a stabiliser such as sodium metabisulphite or formaldehyde. If desired chemical treatment can be combined with cooling treatment. Although green malt is normally produced from barley it is within the invention to use green malt produced from any grain, for example, wheat, rye and the like. The green malt may be comminuted prior to formation of the slurry. The product in this form may be required for end users who are not able to handle and mill green malt. If desired the slurry, particularly slurry formed from comminuted malt, may be separated out into liquid and solid phases. Many of the enzymes in the malt are soluble so that the liquid phase constitutes a product which can be used for example by a distiller. The separated solids can be used as an animal feed. A separated liquid phase would still require to have its pH maintained at or near that of the green malt by cooling and/or chemical treatment for storage and/or transport. The slurry concentration is preferably arranged with as high a solids content as possible. The limit generally being such that the solids will remain in suspension and the slurry can still be pumped. If the solids content is too low the material is uneconomic to transport and the slurry may separate out. The preferred concentration range is from 20 to 50% by weight of solids the particularly preferred concentration within that range being about 25 to 35to. The following examples further illustrate the invention reference also being made to the accompanying drawings. EXAMPLE 1 Green malt prepared, for example, by germinating grain which has been steeped in water until a moisture content of approximately 44% was attained. Germination times were in the order of 3-5 days. The green malt was milled; 2 parts green malt were mixed with 3 parts water, giving a slurry of approximately 24% dry weight. The slurries were chilled to 5, 10, 15 and 20 deg C. The latter is effectively an ambient temperature control. The pH of the slurry was measured at intervals. It can be seen from Fig. 1 that at temperatures of 20"C and 15"C there is rapid fall in pH within 24 hours, but 10 C slows this fall, and 5"C is effective in maintaining the pH above 5.0 for up to 48 hours. EXAMPLE 2 The same system as in Example 1 was used with the addition of potassium metabisul phite-equivalent to 200 ppm sulphur dioxide. The results are shown in Fig: 2. The pH drop was less in this case. The ultimate criterion for the end user of the product according to the invention is that it should ferment with the required "spirit yield". The fermentability of the product is not affected by the treatment of the slurry to maintain the required pH level. The invention is not confined to the specific embodiments described. Many variations and modifications are possible. CLAIMS

8. Green malt slurry as claimed in any preceding claim, wherein the pH of the slurry is maintained at or near the value of green malt by chemical treatment.

9. Green malt slurry as claimed in any preceding claim, wherein the malt is comminuted prior to formation of the slurry.

10. Green malt slurry as claimed in any preceding claim, wherein the solids content of the slurry is from 20 to 50% by weight.

11. Green malt siurry substantially as described herein with reference to any one of the Examples.

12. A liquid phase containing soluble enzymes obtained from the slurry as claimed in any preceding claim.

13. A solid phase obtained from the slurry as claimed in any of claims 1 to 11.