Edible Products. 



156 



[February, 1909. 



The following circular on citrate of 

 lime is issued by the above Company:— 



'In some places citrous juices are 

 simply concentrated in copper kettles 

 over an open fire. This concentrated 

 juice is placed in suitable containers and 

 shipped to us. We cannot recommend 

 concentration, as some of the acid is 

 destroyed, and the evaporated juice is 

 not as valuable per unit of citric acid 

 contained, as the product we now des- 

 cribe, viz., calcium citrate. 



' Calcium citrate is a combination of 

 calcium and citric acid. Its most useful 

 property is the fact that it is in- 

 soluble in hot water; hence, when the 

 proper calcium salt (chalk, whitening or 

 slaked lime) is added to a boiling liquor 

 containing citric acid, the liquor is 

 robbed of its acid, and the latter is 

 recovered in the form of calcium citrate. 



' It is necessary to have a steam boiler 

 useful for generating steam rather than 

 for power ; the steam from this boiler is 

 used :— 



1. To heat the juice in a still in order 

 to drive off the oil. 



2. To keep the juice boiling hot whilst 

 it is converted into calcium citrate. 



3. To heat water with which the 

 calcium citrate is washed. 



4. To heat the driers where the 

 product is dried. 



' We now describe the method for 

 producing calcium citrate from limes, 

 waste lemons, etc. This method might 

 be subject to changes according to con- 

 ditions with which we are not at present 

 familiar. 



The material is pressed between the 

 rollers of an old sugar mill ; a eider press 

 will also suffice- The juice is run into 

 the still (made of copper or lead), where 

 a short boiling removes the oil which is 

 collected at the end of a copper con- 

 denser ; the boiling juice is run through 

 strainers made of brass wire into suitable 

 wooden tanks, where it is neutralized 

 with chalK of lime etc. During neutral- 

 ization the mass is kept as hot as 

 possible by means of a jet of live steam. 



'When the operation is complete the 

 contents of the tank are permitted to 

 settle ; the clear liquid is syphoned off 

 and run away, boiling water is added to 

 the sediment, steam permitted to play 

 through the mass ; and after permitting 

 settlement, the wash water is run away. 

 The hot mass is now run into filter bags, 

 which are securely closed, and placed in 

 a convenient press (a cider press is 

 sufficient). The expressed pulp is now 

 placed on the driers, and when dry is 

 packed into suitable containers. 



' The drying is carried out in flat, 

 double-jacketed pans, made of wrought 

 or east iron, which are so arranged that 

 the pulp may be easily worked over 

 with a spade and thoroughly dried. 



' The difficult part of the operation is 

 to ascertain the point of neutralization, 

 viz., that point when enough chalk or 

 lime has been added to ensure full 

 combination with the acid, and yet not 

 enough to cause a great excess. With 

 a little experience this point is easily 

 found by testing a sample of the contents 

 of the vats. A sour taste indicates that 

 the acid has not all been converted into 

 citrate, and more chalk must be added. 

 When the sour taste is replaced by a 

 distinctly disagreeable characteristic 

 taste, the acid has been removed from 

 the liquor. 



' A further test is to take from the vat 

 a sample of the clear liquor and also a 

 sample of the sediment. If, when more 

 chalk is added to the hot sample of clear 

 liquor, effervescence takes place, there 

 is still free acid in solution. 



'If, on the other hand, hot raw juice 

 is added to the sediment and decided 

 effervescence takes place, there is an 

 excess of chalk present.' 



Appendix II. 



Cultivation of Limes at Montserrat. 



The following particulars have been 

 supplied'by Mr. W. Robson, Curator of 

 the Botanic Station, Monsterrat :— 



The plantations are chiefly confined to 

 the sheltered valleys aud slopes of the 

 lower lands. In addition to the natural 

 shelter, belts of white cedar (Tecoma 

 leucoxylon) are frequently used. This is 

 practically the only plant used as a wind 

 break, and it is planted at distances of 

 about 150 yards, either in single rows or 

 in double rows about 4 feet apart. 



Seeds are sown in small nursery beds 

 and remain there until ready for trans- 

 ferring to the field. No transplanting 

 into nursery beds is done. In some 

 instances planting is successfully done 

 at stake in the field, when several seeds 

 are sown at each stake and only the 

 most vigorous of the seedlings allowed 

 to grow. 



Showery weather is chosen for plant- 

 ing, and small beds are made with a fork 

 in which to put the plants. A distance 

 of 18 feet by 18 feet is the most general 

 for planting, although in the drier dis- 

 tricts 12 feet by 12 feet is practised. 



For the first two years of growth, 

 cotton has been successfully grown as a 

 catch crop. 



