Semi-solid fermentation of straw

• US 3,937,845 A
• Filed: 01/08/1975
• Issued: 02/10/1976
• Est. Priority Date: 01/08/1975
• Status: Expired due to Term

• Current Assignee: United States Department Of Agriculture
• Original Assignee: United States Department Of Agriculture
• Inventors: Han, Youn W., Anderson, Arthur W.
• Primary Examiner(s): Monacell, A. Louis
• Assistant Examiner(s): Penland, R. B.
• Application Number:
  US05/539,552
• Time in Patent Office: 398 Days
• Field of Search: 426/52, 426/49, 426/2, 426/807, 426/53, 426/54, 426/372-374, 426/69, 426/18, 426/210, 426/615, 426/626, 195/31, 195/33, 195/82
• US Class Current: 426/53
• CPC Class Codes: A23K 10/12 by fermentation of natural products, e.g. of vegetable material, animal waste material or biomass
• CPC Class Codes: A23K 10/32 from hydrolysates of wood or straw
• CPC Class Codes: C12N 1/22 Processes using, or culture media containing, cellulose or hydrolysates thereof
• CPC Class Codes: Y10S 426/807 Poultry or ruminant feed

Abstract

The digestibility and protein content of straw is enhanced by treating it with dilute acid, ammoniating the acid-treated straw, and fermenting it with a yeast such as Candida utilis. The so-treated straw is useful as a feed for ruminants and other animals.

Claims

1. A process for increasing the digestibility and protein content of straw, which consists of

a. mixing 1 part of straw with about 2 to 4 parts of aqueous sulphuric acid having a normality of about 0.1 to 1, and holding the mixture at about 100°

to 125°

C. for about 30 to 60 minutes,

b. adding to the acid-treated straw an amount of ammonia to provide a pH of about 4.0-4.5,

c. aerobically fermenting the ammoniated acid-treated straw, which is a moist fibrous mass having a solids content of about 20-33% and a moisture content of about 80-67%, with a microorganism selected from the group consisting of Candida utilis, Pullularia pullulans, and Trichoderma viride, at a temperature of about 30°

C. for a period of about 1 to 7 days, and

d. drying the so-fermented product.

2. A process for increasing the digestibility and protein content of straw, which consists of

a. mixing one part of straw with about 3 parts of aqueous sulphuric acid having a normality of about 0.5, and holding the mixture under autogenous pressure at a temperature of about 121°

C. for about 30 minutes,

b. cooling the resulting acid-treated straw to room temperature and adding thereto an amount of ammonia to provide a pH of about 4.0-4.5,

c. inoculating the ammoniated acid-treated straw, which is a moist, fibrous, semi-solid mass having a solids content of about 25% and a moisture content of about 75%, with about 5% of a culture of a microorganism selected from the group consisting of Candida utilis, Pullularia pullulans, and Trichoderma viride, and aerobically fermenting the inoculated mass by tumbling it in the presence of air, said fermentation being conducted at a temperature of about 30°

C. for about 1 to 7 days, and

d. drying the so-fermented product.

3. The process of claim 2 wherein the straw is ryegrass straw.

4. The process of claim 2 wherein the microorganism is Candida utilis.

5. The process of claim 2 wherein the microorganism is Pullularia pullulans.

6. The process of claim 2 wherein the microorganism is Trichoderma viride.