Vol. XVI. No. 387. 



THE AGRICULTURAL NEWS. 



59 



conditions, wind is largely responsible for the spread of 

 young scales insects, and show how easily a clean orchard 

 may be infested from neighbouring orchards, or from other 

 host plants growing in the vicinity. 



There is no doubt that the wind is a factor in the spread 

 of such small insects as thrips, white flies, plant lice, etc. 

 during the periods when these are most active. This 

 question of dispersion by wind is of special importance in the 

 case of an insect which has several alternate host plants, 

 when it is quite possible for an insect to be carried by the 

 wind from its wild host plants to its alternate host plants of 

 economic value. Under West Indian conditions many of 

 these minute forms are usually controlled by their parasitic, 

 predaceous, or fungus enemies, or they can be kept in check 

 by good methods of cultivation. 



The data presented in this article further emphasize the 

 importance of thorough co-operation between growers in all 

 measures of control, especially where a pest is known to be 

 prevalent over large areas. 



J.C.H. 



ECONOMY IN USING POTATOES. 



An article appeirs in the Journal ot tJit B lard of 

 A'jriculture of England and Wales on economy in using 

 potatoes. Trial has shown that the most common method 

 of cooking potatoes — paring, then boiling after placing the 

 pared tubers in cold water — is the most wasteful method 

 practised. This is so for three reasons: first, not only the 

 skin, but the surface layer and perhaps 10 per cent, of the 

 flesh are removed by thick paring, partly owing to deeply 

 sunk eyes and surface irregularity; the total loss may, 

 indeed, amount to as much as 20 per cent, of the whole 

 tuber — or 1 B). in every o fc. The surface layers, which are 

 wasted, contain a larger percentage of solids than the 

 remainder: and lastly, the subsequent boiling dis.solves the 

 foluble ingredients of the potato and also breaks down the 

 outer surface into the water — which is thrown away. 



E.xperinients on the subject have shown that pared 

 potatoes put into cold water and boiled lost 15'8 per cent, of 

 their protein or fieshfonning substances, IfS'S percent, of 

 their ash or mineral matter, and some .3 per cent, of their 

 carbohydrates or starch. Plunged at once after paring into 

 boiling water and boiled, they lost 8'2 per cent, of their 

 protein, about 18 per cent, of their ash, and a small amount 

 of their starch. On the other hand, when boiled in their 

 jackets, potatoes los: only 1 per cent, of their protein, a little 

 over .3 per cent, of their ash, and practically none of their 

 starch whether plunged in cold or hot water at the .start. 



It is clear, therefore, that if pared potatoes are placed 

 direct in boiling water, the loss in boiling is very much re- 

 duced compared with the usual methods — placing in cold 

 water; steaming instead of boiling also reduces the loss; while 

 boiling or steaming in their jackets reduces all losses to 

 a minimum — both the boiling losses and the primary 20 

 per cent, loss due to paring are alm".st wholly avoided. 



Considering the facts already outlined, in cooking for 

 the table, potatoes should be boiled or steamed in their jackets. 

 Slow cooking is desirable so that the skin does not bake on to 

 the flesh and so cause loss The skin should be pricked or cut 

 before baking to permit the escape of steam. If because of 

 injuries to the surface or for any other reason, potatoes 

 must be pared, they should be cooked by steaming, or by 

 cooking in the smallest possible quantity of water, which 

 should be boiling when the potatoes are put in. The water 



should not be thrown away but should be used as a basis 

 for soups. The same applies to the cooking of beans. The 

 loss in boiling is reduced if salt is added to the water. 



As a general rule with all vegetables, it is more econo- 

 mical to steam them rather than to boil them. The 

 information given above refers primarily to English potatoes, 

 but the general principles hold good for sweet potatoes and 

 yams and other West Indian vegetables. In view of the 

 high cost of living in the West Indies and the possible 

 shortage of food in the future, it will be well to bear thd 

 foregoing facts in mind, as it will be seen that the prepara- 

 tion of vegetables for the table is in many cases accompanied 

 by a very considerable loss of nutrient material. 



BREAD 



DILUTED WITH SWEET 

 POTATO MEAL. 



In conne.xion with the notes on bread diluted with 

 potato meal which recently appeared in the AyricuKural N'ews, 

 the following notes on experiments that are being conducted 

 in St Lucia, forwarded by Mr. A. J. Brooks, Agricultural 

 Superintendent, are of interest. 



The initial experiments gave a |-lb. of dried flour per 

 2 ft), of freshly dugged sweet potatoes The potatoes were 

 carefully scrubbed clean and then cut into thin slices 

 and dried in an ordinary oven. When dried to such an 

 e.xtent that it became brittle, the slips were placed in a mill 

 and carefully ground to a very fine powder. Mr. Brooks has 

 kindly forwarded a sample of this meal which seems good and 

 palatable. Drying in an ordinary oven however, has had the 

 effect of slightly caramelizing the sugar in the meal, thus 

 imparting a cooked flavour and at the same time darkening 

 ths product. This can be got over by drying at a lower 

 temperature, or by sun drying, though it may be thought 

 by some that the features produced by baking are not 

 objectionable. 



Samples of loaves of bread were made from the following 

 mixtures: wheat flour 3 parts, sweet potato flour 1 part; 

 equal parts of wheat and potato flour. Very satisfactory 

 bread was made from the 3 : 1 mixture. The colour and 

 consistency were rather like brown bread. Bread made from 

 equal parts of these flours was not as satisfactory. 



Probably the colour of sweet potato flour could be 

 improved upon by modifying the method of drying. Mr. 

 Brooks states that the question of slicing the potato is receiving 

 attention, as it is important to reduce the cost of preparing 

 sweet potato flour to the lowest possible point. At present 

 satisfactory results are being obtained by adapting a poultry 

 chaff cutter to suit the requirements. 



It is understood that experiments are also Tseing con- 

 ducted in connexion with the manufacture of bean flour with 

 the object of using it in conjunction with wheat and sweet 

 potato flour. 



Viability of Kiln-dried Corn —In regard to the 



interesting question of the viability of kiln-dried corn, 

 several tests made in St. Vincent have shown that the 

 percentage of germination runs from 23 to 26. This of 

 course is too low to make kiln-dried corn of much value 

 for planting purposes. 



