CITRIC ACID FROM SUGARCANE MOLASSES

Citric acid (C6H8O7, 2 – hydroxy – 1,2,3 – propane tricarboxylic acid), a natural constituent and common metabolite of plants and animals, is the most versatile and widely used organic acid in the field of food (60%) and pharmaceuticals (10%). It has got several other applications in various other fields. Currently, the global production of citric acid is estimated to be around 736000 tones/year (Química e Derivados, 1997), and the entire production is carried out by fermentation. In Brazil, almost the entire demand of citric acid is met through imports. There is constant increase (3.5-4%) each year in its consumption, showing the need of finding new alternatives for its manufacture.

Citric acid was first isolated by Karls Scheels in 1874, in England, from the lemon juice imported from Italy. Italian manufacturers had monopoly for its production for almost 100 years, and it was sold at high cost. This led extensive attempts all over the world to find alternatives way for its production, which included chemical and microbial techniques. In 1923, Wehmer observed the presence of citric acid as a by-product of calcium oxalate produced by a culture of Penicillium glaucum. Other investigations showed the isolation of two varieties of fungi belonging to genus Citromyces (namely Penicillium). However, industrial trials did not succeed due to contamination problems and long duration of fermentation (Rohr et al., 1983). The industrial process was first open by Currie, in 1917, who found that Aspergillus niger had the capacity to accumulate significant amounts of citric acid in sugar based medium. He also showed that high concentrations of sugar favoured its production, which occurred under limitation of growth. In the thirties, some units were implanted in England, in Soviet Union, and in Germany for the commercial production. However, the biochemical basis was only cleared in the fifties with the discovery of the glycolytic pathway and the tricarboxylic acid cycle (TCA). Consequently, an improved process employing submerged fermentation was developed in United States.
Although methods were well developed to synthesis citric acid using chemical means also, better successes were achieved using microbial fermentations, and over the period of time, this technique has become the method of ultimate choice for its commercial production, mainly due to economic advantage of biological production over chemical synthesis. Much attention has been paid on research to improve the microbial strains, and to maintain their production capacity.

Citric  acid  was  first  isolated  from  lemon  juice   and crystallized  as  a  solid by Scheele in 1784.   It  is  found  as natural constituent of citrus fruits, pine apples, peaches,  figs and  other  fruits and tissues.  The citric acid  extracted  from these products is known as a”natural citric acid” in contrast  to “fermentation citric acid” lemons, limes and pine apples are  the principle  sources  of  natural citric acid,  which  is  produced chiefly  in  Italy, especially Sicily, and  also  in  California, Hawai and the West Indies.

It has made the United States self sufficient in respect  to the  citric acid supply and greatly changes the commerce  of  the world in citric acid and calcium citrate.

Recent developments in the citric acid fermentation  include the  change from the older established shallow   pan method to a deep tank submerged method.

A group headed by S.M. Martin of the National Research laboratory of Canada has been especially active in the development  of  the  submerged production of  citric  acid  from ferrocyanide-treated beet molasses by Aspergillus Niger.

In  Russia, Imshenetskiietal through the use of  ultraviolet radiation, obtained an A. Niger mutant that produced 16-22% more citric  acid  than  parent strain, which is  used in Commercial production of this product. The mutant strain produced 25-30% less  mycellium than the parents yet it  consumed  26-51%  more sucrose per gram of dry mycellium. The yield of citric acid from the sugar consumed varied form 57-74%.

INTRODUCTION
MARKET SURVEY
MARKET SEGMENTATION
WORLD PRODUCTION PATTERN OF CITRIC ACID
CLOBAL CONSUMPTION PATTERN OF CITRIC ACID
GLOBAL DEMAND & SUPPLY OF CITRIC ACID
MICRO-ORGANISM FOR CITRIC ACID PRODUCTION
TABLE MICRO-ORGANISMS EMPLOYED FOR CITRIC ACID PRODUCTION
STRAINS SELECTION AND IMPROVEMENT
INDUSTRIAL PRODUCTION OF CITRIC ACID
BLOCK DIAGRAM OF CITRIC ACID (MONOHYDRATE) & ANHYDROUS
RECOVERY OF CITRIC ACID (MONOHYDRATE & ANHYDROUS)
PRODUCTION TECHNIQUES AND RAW MATERIALS
LIQUID FERMENTATION
TABLE RAW MATERIALS EMPLOYED IN SUBMERGED FERMENTATION
FOR CLTRIC ACID PRODUCTION
SOLID-STATE FERMENTATION
PRODUCTION DETAILS OF CITRIC ACID
SURFACE CULTURES
SUBMERGED CULTURES
TECHNICALITIES IN CITRIC ACID PRODUCTION
1.   SELECTION OF ORGANISM:-
2.   SELECTION AND OPTIMIZATION OF MEDIA:-
3.   OPTIMIZED MEDIA IS USED FOR THE CITRIC ACID PRODUCTION
IN FERMENTATION.
PREPARATION OF CULTURE
ISOLATION:-
PROCESS FLOW DIAGRAM FOR MANUFACTURE OF CITRIC ACID
MASS BALANCE PROCESS DIAGRAM FOR SINGLE FERMENTOR
DESIGN CALCULATIONS
1.   FERMENTOR DESIGN AND ENERGY BALANCE.
2.  DESIGN OF THE FERMENTOR:-
NO OF FERMENTORS:-
HEIGHT OF THE LIQUID :-
SELECTION OF THE IMPELLER:-
SELECTION OF AIR SPARGER TYPE:
VELOCITY AIR THROUGH EACH HOLE:-
FLAT BLADE
THICKNESS OF SHELL AND HEAD :-
SELECTION OF ATTACHMENT:-
DESIGN DATA:-
OVERHEAD STORAGE TANK FOR MOLASSES:-
MOLASSES TREATMENT TANK:-
DIMENSIONS AND SHAPE OF THE STERILISER:-
FERMENTED BROTH HOLDING TANK:-
VOLUME OF ACID CHAMBER:-
VOLUME OF CALCIUM CITRATE:-
DESIGN DATA OF FILTRATION UNIT:-
FILTRATION UNIT:-
COOLING EQUIPMENTS:-
BOILER SPECIFICATIONS:-
HEAT REQUIRED FOR MOLASSES STERILISATION:-
PROCESSING OF CITRIC ACID FROM SUGARCONE MOLASSES
BY ASPERGILLUS NIGER UNDER DIFFERENT FERMENTATION
COLLECTION OF WASTE MATERIALS
PREPARATION OF INOCULUMS
FERMENTATION
ANALYSIS OF FERMENTATION MEDIA
ESTIMATION OF SUGARS
EXTRACTION OF CITRIC ACID
ESTIMATION OF CITRIC ACID
SAMPLE PREPARATION
HPLC ANALYSIS
STATISTICAL ANALYSIS
FACTORS AFFECTING CITRIC ACID PRODUCTION
MEDIUM AND ITS COMPONENTS
PROCESS PARAMETERS
PROPERTIES
TABLE 1.  DENSITIES OF AQUEOUS CITRIC ACID SOLUTIONS
AT 15OCA
TABLE 2.  FREEZING POINT DEPRESSION AND BOILING POINT
ELEVATION OF AQUEOUS CITRIC ACID SOLUTIONSA
TABLE 3. SOLUBILITY OF ANHYDROUS CITRIC ACID IN WATERA
TABLE 4. SOLUBILITY OF HYDRATED AND ANHYDROUS CITRIC ACID
IN AQUEOUS SOLUTIONS OF ETHYL ALCOHOL AT 25OCA
TABLE 5. SOLUBILITY OF HYDRATED AND ANHYDROUS CITRIC ACID
IN SOME ORGANIC SOLVENTS AT 25OCA,B
CHEMICAL PROPERTIES
USES AND APPLICATION OF CITRIC ACID
TABLE APPLICATIONS OF CITRIC ACID
I.S.I.  SPECIFICATIONS
QUALITY TESTING OF CITRIC ACID
1.   DETERMINATION OF CITRIC ACID CONTENT
2.   DETERMINATION OF SULPHATED ASH
3. TEST FOR HEAVY METALS (AS PB)
OUTLINE OF THE METHOD
QUALITY CONTROL TEST FOR RAW MATERIAL
SUPPLIERS OF RAW MATERIALS
SUPPLIERS OF PLANT AND MACHINERY

APPENDIX – A:

1.      COST OF PLANT ECONOMICS
2.      LAND & BUILDING
3.      PLANT AND MACHINERY
4.      FIXED CAPITAL INVESTMENT
5.      RAW MATERIAL
6.      SALARY AND WAGES
7.      UTILITIES AND OVERHEADS
8.      TOTAL WORKING CAPITAL
9.      COST OF PRODUCTION
10.      PROFITABILITY ANALYSIS
11.      BREAK EVEN POINT
12.      RESOURCES OF FINANCE
13.      INTEREST CHART
14.      DEPRECIATION CHART
15.      CASH FLOW STATEMENT
16.      PROJECTED BALANCE SHEET