340 



THE AGRICULTURAL NEWS. 



Oi roBEB I'.'!, 1915. 



FRUIT PRODUCTS. 



THE MAKING OF FRUIT PULP. 



The c mi rci i\ repn sentative of this Department 



in Canada i enquire whether there is any 



possibility of inl ires) being shown in the West Endies 

 in the production of fruit pulps pul up in 10H). 

 209)., or 501h. tins for us.' by manufacturers of jams. 

 jellit s and confectionery. Our representative is of 

 opinion that soursop, mammee apple Gfuava and any 

 other fruit oi these types might be got into largi i 

 consumpt ion by tins met hod. 



The above sugg stion appears to be worth 

 considering. Oranges, of which a large number are 

 at presenl wasted, might also be utilized in this way if 

 n use for bhe pulp could be found in the jam and 

 confectionery trades, as for example in making marma- 

 lade. Pine-apples could not be employed as they lose 

 flavour on being heated, but even for pine-apple there 

 might arise a demand. 



The following article, reproduced with certain 

 omissions from the Journal of the Board of Agri- 

 culture (England), explains how fruit pulps are made 



As an article of food, fruit is generally used fresh, but 

 there are various methods of preserving it, such as jam-making 

 and fruit bottling, which make it available when fresh fruit 

 cannot be obtained, and which in seasons of heavy crops form 

 a valuable means of preventing waste. Among such methods 

 'fruit pulping' is not so widely known as it might be, but 

 specially merits attention on account of its simplicity. It 

 consists in reducing the fruit to a state of pulp by heat, 

 generally by means ol steam. The treatment sterilizes the 

 fruit, so that it may be kept under suitable conditions with- 

 out decomposition toi an indefinite period. The product is 

 known as 'fruit pulp'. The process can be carried on by any 

 grower who has on his premises an ordinary steam boiler. 



Fruit pulp is chieflj used in jam making. It is con- 

 verted into jam where convenient to the manufacturer. 



The essential requirements for the preparation of fruit 

 pulp on a commercial scale area steam boiler, and barrels, 

 tins, drums, or jars, in which the pulp can lie stored. The 

 best qualities of pulp are stored in large stone jars, but these 

 are expensive. The quickcsl and most eonvenient method of 

 storage on a farm is to use casks, ('asks which have 

 contained wine or spirits are usually employed. They should 

 be in good, sound condition, and preferably made of oak. 

 Copper ladles and tunnels are required for idling the casks. 



In a jam factory, pulp is usually prepared in the steam- 

 heated pans otherwise used for boiling jam, but in the 

 absence of special jam making machinery the method Ijere 

 described may be adopted 



Three w len vats, tubs, or halt-bands should be placed in 



a row in a position convenient for connexion with existing steam 

 piping. Whilst the contents of one vat are being Steamed, 

 a second will be in process of tilling, and a third being 



emptied, so thai with a sufficient head of steam the process 01 



pulping will proceed continuously. A coil of 1 inch copper 

 piping is required. Thisshouldbe pierced with not more than 



fcwentj | inch h'.les. The coils should be placed in the vat 



or tub so as to reach to within a few; inches of the bott 



and tic- pipe connecting it with the boiler should be fitted 

 with a rapid coupling so that the coil may be quickly 

 transferred from one vat to the next. for continuous 

 working two such coils are required as it is not possible to 

 insert a coil amongst the fruit after the vat has been tilled. 



The vats should be provided with wooden covers to confine 

 the steam whilst the steaming process is going on. With an 

 8 h.p. boiler working at a pressure of lolii.. three vats of 100 

 gallons capacity can be kept in fairly continuous use. Five 



CWt. of plums or apples may be cocked at a charge, and, if 

 in be maintained, tl, . may be put through 



per h 



Sti im is also required for s tiding out and sterilizing 

 the interior of the barrels before rilling them with pulp. 



The process of sterilization [a completed by burning 



tl rag dipped in melted sulphur within the hung hole, and the 

 bung is then kept .dosed until the barrel is ready for tilling. 

 The casks must be completely filled and bunged down 

 whilst the pulp is boiling hot, and placed in a position where 

 thc.\ ept undisturbed until the pulp is required for 



use. They should lie on their side with the bung uppermost, 



and if there is any sign of fermentation a small hole should 



be bored in the w leu bung md closed with a spiggot. The 



latter should be lifted daily until fermentation his ceased and 

 the contents of the cask have settle,! down. 



If the casks are subsequently moved, the same process! 

 of daily opening the same hole in the bung must be repeated. 



If tins or jars, after previous scalding, are tilled with 



boiling pulp and at ■•■ hermetically closed, the contents 



should keep indefinitely without fermentation. Tins used 

 for pulp should be well lacquered inside. 



PAPAIN : ITS PREPARATION AND DIGES- 

 TIVE PROPERTIES. 



An important paper by Dr. D. S. Pratt, on the subject 

 of papain, has recently appeared in the Philippine Journal 

 of Science (Vol. \, Section A, No. L, January 1915). The 

 investigation with which the paper deal.-, was undertaken for 

 the purpose of comparing papain gums made in a variety of 

 ways, and to ascertain whether it is possible to conserve 

 the entire efficiency of fresh latex by employing proper 

 methods for dry wig. In proceeding to do this it was felt 

 that some standard method for analysis was required, and 

 one which would give accurate results without calling for 

 elaborate apparatus or laborious manipulation. The methods 

 at present used seem to depend largely upon some sample of 

 papain gum selected as a standard. The following scheme 

 therefore tor assaying papain was adopted. It has given 

 satisfactory results in many hundreds of cases and m 

 recommended is simple, rapid, and accurate. Tt has the 

 advantage of being carried out readily in any laboratory, 

 and is all the information necessary for determining 

 quality of the sample: 



'Milk, as nearly as possible free from butter fat, is the 

 most satisfactory material to employ as substrate. The 

 various well known brands of condensed skitnmed milk 

 possess reasonably constant composition, and are well 

 to the purpose. I employed a |i' per cent, solution of 

 sweetened condensed skimmed milk in the analyses recorded 

 in this paper, not only because fresh skimmed milk was 

 not procurable in Manila, but also for the reason that the 

 canned milks keep well and ire thus always available. 



'The enzyme solution was prepared by dissolving - 75 

 gram of powdered papain in 150 cubic centimetres of 



distilled water. Papain i- not completely soluble in Water. 

 hut by wanning the mixture for thirty minutes in the 

 thermostat at 10 the active principle is dissolved, and upon 

 filtering a clear solution is obtained. Well-prepared gums 



give a colourless tiltrate. which is slightly acid and -h 

 marked tendency to froth. The digestions were carried out 

 in 1 50 C.C. I''rlenmeyer llasks. 



