SCIENCE IN COOKING.

Dominion, Volume 1, Issue 1, 26 September 1907, Page 3

SCIENCE IN COOKING.

FOOD VALUES EXPLAINED.

The following is the first of a scries of articles on. cooking • and diet by Miss G. Ivey, cooking-instructress' to tho Board of Education, and holder of a full diploma from tho National Training School of Cookery, London:—

•If our new Dominion is to prosper it is necessary that all its resources of food should be thoroughly understood and correctly applied, for from too much or too little nourishment, or nourishment that is .unsuitable., there will .result a race inferior in mind and body. Having in Now Zealand plenty of good food, we should be able to utilise it for tlip improvement of the race. To spend money in buying medicine is not tho way to' success. Neither is it a pleasant means of supplementing tho deficiencies of a diet. A perfect diot must supply ,;l) proteids of .flesh-forming foods, (2) carbonaceous or heat-giving and forceproducing foods, and (3) mineral foods in tho right proportions to sustain lifo and health.

From plants may bo obtained all foods necessary for man, but in different proportions and qualities from similar foods obtai iiablo f rom animals. Animal food cannot aloiies nppl.v all necessary nutriment. The br-yfc way is to draw for nourishment from both sources. We will, however, leave the discussion of vegetarianism until wo liavo studied the values of the various foods-—then the merits of both will lie before us.- We must remember that it is not only necessary to consider the chemical composition of the food, but also 'its cost, and the time necessary for its preparation, the amount of fuel to eool; it, and its suitability for those v/ho are to eat it. In discussing the food value of vegetables we will begin by considering the different groups of nutritive substance uhicli enter into their composition. Starch a ml. sugar are very plentiful in the. vegetable ■kingdom. It is interesting to remember that in plants starch is convertible into sugar and .■!ii;;ar into starch. What takes place U in brief,-this:-The plant keeps sugr.r iJiout it I'm its own lis:-, f>'!• surplus it converts iiitn starch, v;\ i: str.ros in number? ol minute cells--a uljvor arrangement,

as starch,• r being - insoluble in cold water, in not washed away from a broken plant.by tho rain. The walla of the cells and tlie framework which holds .-thorn-together aro made of cellulose,. tho most familiar form of which is paper. If wo pour boiling v/ater 011 the grains they sw"ell up and burst. It is this bursting of the cells wo seek to briiig about by cooking vegetable foods, so that tlie nourishment may ho easily attacked by (ho digestive juices. If overcooked, the flavour and nourishment of boiled vegetables is partly lost because too much wator is absorbed by tho cells, which become sodden. Another form of tho sugar-starch group is a jellyforming sulistanco found especially in fruit. Owing to this fruit solutions will ofteu form a jelly. 011 cooling. Tho only othor - important carbonaceous foods are tho fats and oils. Thoy occur very plentifully in'nuts.

As in meat, the proteids or fleshforming foods in vegetables may bo divided into those v.-Mch are very

, ..urishing and those which have littlo nutritive value. '1110 vegetable protoids aro very easily dissolved by salt aiid water, so should not bo allowed to soak in such a solution. Potatees, etc. should not be peeled and left soaking in cold water, as thoy will loso ■ flavour and nourishment. Vegetables aro fairly free from the harmful proteids which aro so especially injurious for gouty people, who would therefore do well to avoid meat and got their proteids from vegetable sources. If properly cooked and used, beans, peas, lentils, etc., tho pulse vegetables, will give us tho choapcst form of flesh-forming foods. All frcsa vegetables contain a largo proportion'of water, from 70 per cent, to 90 per cent. So that out of a lOOcl.. spent 011 vegetables DO of .them are spent on wator. • Strange as it may seem, a cabbage contains a larcor proportion of water than milk. The reason green vegetables look so solid is that they havo a large :framc\vork of' ■cellulose, but thoy are practically paper and water with mineral salts, which aro blood-purifiers. Animal foods, lost .water whilst being soaked; vegetables will absorb' water whilst being cooked. In getvjd' of this largo quantity of wator most of tho commoner vegetables havo been dried. This makes them easier for trausport and docs not interfere with their nutritivo powers, except to bring-then into a more concentrated form. 'J'lio minoral salts arc" very plentiful and very important, but thcy are moro easily dealt with when discussing each vegetable separately. Common salt should bo used freely in the diet of those living exclusively 011 vegetables. On "the other hand, there is no better -way-of- counteracting the bad effects ; of. a salt-meat diot than by the use of lemon juice and 'fresh vegetables. Tho art of cooking vegetables is so little 'understood, and they aro usually cooked so unattractively, that wo do not sufficiently use this excellent and varied source of obtaining nourishment. W,e also, seem to lose sight of' their groat, medicinal value. Living in a warm climate, our diet should 1 contain' a large' quantity of vegetable food.

Owing to tho, bulkiness of vegetable foods,'it take's somo time for the digestiro jnicj3 to penetrate them. Cellulose übre, too,"except in quite young ■ ycgotables, is indigestible. Though vegetables are digested in the mouth and in the intestines, it must not bo-forgotten that;.tho'stomach has a good dcr.l of mechanical work to do in passing the food, so, when rest is necessary for it, nutriment'should be got from other sources. In chronic rheumatism, , regotables _ • (especially celery •• 'and Sjiaiiish ■■onions)--niay bo freely usciL

Having .'Said »■ littlo about vegetables in general, it is now timo to discuss them. separately or..in groups. Thoy are generally divided into five groups, i.e., (1) Tho pulses—peas, beans, etc. ' (2) The ' cereals—wheat, oats', maize, etc. . (B.)' .Roots and tubers. (4) '. Green' vegetables. (0) Fruits and nuts. .%

1. As tho pulses contain so; much flesh-forming food and aro very cheap they have' been called the "poor man's bobf." Thoy, should bo .oaten with other foods rich in starch, sugar,, fat, or oil. : Beans with bacon or rice are examples, of mixtures.' : In .pulse vegetables tho protoid . is. 'called • legumin, and so resembles casein, the protoid; of milk, t!iat'-in:Soine parts of China' cfcecaes aromaUo from it.-Len-tils aro' principally used., as. a'. vcgcablo puree, or for soup. Thoy aro moro. digestiblo than peas or beans, and contain less sulphur. An pulse vegetables do not readily soften in hard water, tho water they aro soaked or cooked in should havo soda added to it in order to soften it. If thoy aro cither old or dry they want long cooking to soften tho cellulose. Orriiig to the similarity of tho members of this group of' vegetables it is not here 1 necessary to'discuss them separately.