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About The Chemawa American (Chemawa, Or.) 19??-current | View Entire Issue (Nov. 12, 1919)
4 PAG E 4 T H E C H E M A W A A M E R IC A N FOOD D R Y IN G PROCESSES T h e scarcity an d h ig h cost of food m aterials d u rin g th e w ar and since have m ade th e preservation and con serv atio n of ev e ry th in g edible m ore im perative th a n ever before. K n o w n and tried m ethods of can n in g , d ry in g and otherw ise p reserv in g foodstuffs have been w idely em ployed and m uch tim e and effort have been exp en d ed in the hope of im proving old processes and discovering new ones. M any of our foods, p a rtic u larly m ilk, fru its and vegetables, are m ade u p largely of w ater, w ith only a sm all p ercentage of solids. T h e ideal m ethods of p re serv in g them w ould be to rem ove th is w ater w ithout affecting deleterio u sly th e solids for food purposes. Probably d eh y d rated foods, as the dried products are called, will never be as good as fresh but w ith p ro cesses now in use ex cellen t resu lts are o btained. T h is is p artic u larly tru e in th e case of m ilk, grapes, p ru n es, peaches, apples, eggs, etc. In w arm , dry clim ates th e p ro d u cts to be dried may be sim ply spread o u t in the su n . T h is m ethod, w hile sim ple an d inexpensive, has several objectionable fe a t ures. F o r in stan ce, th e food is exposed to insects and o th e r c a n tam in atin g agencies d u rin g th e d ry in g process u n less special p recau tio n s are taken against th em . M oreover a sudden show er m ay dam age or ru in large q u a n titie s of th e p ro d u ct, en tailin g heavy financial loss. G overnm ent ex p e rts who have been try in g to d eter m ine the best d ry in g processes to reduce th e w eight and bulk of fru its, vegetables, etc., an d at th e same tim e preserve them indefinitely have found several th at work well. In one the food m aterial, sliced, chopped or otherw ise prepared, is placed on rack s or screens w hich for convenience may be m ounted on tru ck s. T h e m aterial is then placed in special tu n u e ls th ro u g h w hich w ater operated fans force strong cu rren ts of w arm , d ry air. T h e tray s are g rad u ally moved th ro u g h th e tu n n el, th e air tak in g up th e m oisture in food u n til it is finally d eh y d rated sufficiently. A nother m ethod th a t has proved highly satisfactory in m any respects is to place th e food m aterial on shelves in closed cham bers. W arm air m uch below norm al pressure is th en introduced and th is rap id ly absorbs the m oisture in the fru it or vegetables. T h e chief objection to th is process is th a t the cellular stru ctu re of the food m ay be broken dow n w hile in the partial vacuum of th e cham ber. In a th ird process w hich has been tried w ith fairly satisfactory results th e m aterial to be dried is placed on the perforated floor of a k iln , heated by stoves u n d ern eath it. T h e m aterial, spread over the floor to a dep th of four or five inches, is stirred and tu rn ed from tim e to tim e so th a t th e w arm , dry air com ing u p th ro u g h it rapidly e x tra c ts its su rp lu s m oisture. B ut unless th e g reatest care is exercized in th is process th e p ro d u ct is likely to lack seriously in u n ifo rm ity . O n th e whole, however, resu lts obtained w ith th e kiln are m ore satisfactory th a n those obtained w ith th e tu n n e l as in th e latter th e m aterial m ay be overheated or scorched. Foods properly d ried by these m ethods, it is said, retain th eir n atu ral color and flavor rem arkably well. W h en th e w ork is carefully done they com e out very m uch the sam e as they go in except th a t m ost of th e w ater is rem oved. On soaking them in w ater they resum e th e ir form er shape and size and after being cooked th ey taste about th e sam e as w hen fresh. SU BSTITUTE FOR X -R A Y S Beyond doubt the m ajority of our readers have some know ledge of the x -rav and its w onderful u tility along certain lines. I t is q u ite probable th at they will be in terested to know th a t still fu rth e r advance m ent along this avenue of science has been m ade. O ne n ig h t w hile w aitin g for a car, says a w riter in the E lectrical E x p erim en ter, Dr H u n te r Held his hand over th e glow ing lens of a sm all flashlight and was m uch interested to note th e red glow o f th e fleshy part of th e m em ber and th e shadow y outlines of the bones. H e reasoned th a t the red rays of th e lig h t penetrated the flesh and th at by in te n sify in g them a photograph sim ilar to those obtained w ith th e x -ra y s w ould be pos sible. T h e chance observation p artic u larly interested him because he realized th a t a sim ple device th a t could be m ore readily carried about th a n th e ord in ary x-ray ap p a ra tu s would g reatly facilitate th e diagnosis of fra ctu res and w ould m ake th e advan tag es of shadow p h o to g rap h y available to p atien ts w’lio otherw ise w ould be den ied them . H e first tried placing his h an d over a panchrom atic p h o to g rap h ic plate and exposing it to an electric lig h t. T h e result was a fairly good picture of th e bones of his hand. T h en he m ade a black box w ith an opening at one end sufficiently large to adm it a hand or a ’foot. T h e box was made collapsible so th a t it could be carried about easily. In th e top w’as fixed an iris diaphragm sim ilar to th at of an o rd in ary cam era. A sh u tte r was provided w ith an extrem e red ray filter above it. In th e bottom of th e box a plate-holder was fixed w ith a developing tank beneath it to facilitate th e develop m ent of plates after exposure. U sing th is ap p aratu s w ith a p anchrom atic p h o to g ra- phic plate brushed w ith rosin solution to render it more sensitive, excellent pictures of th e bones have been ob tained. T h e filtered lig h t— rays w hich pass most readily of all visible lig h t th ro u g h blood— is th u s m ade to do essentially th e sam e w ork as the x-rays, produced by expensive, com plicated apparatus. D r. H u n te r is convinced th a t by increasing th e sen sitiveness of th e photographic plate and intensifying th e lig h t it'w ill be possible to use his invention for abdom inal and intercostal ex am in atio n s. W ith a cam era of this k ind, he says, a physician can readily assure him self before leaving th e hom e of a p atien t w hether the broken bone he has set has been attended to p ro perly. E v en tu ally he believes, th e device will be widely used for this purpose. T h e x-rays som etim es have a harm ful effect and if injudiciously used m ay cause incurable b u rn s or m al ig n a n t grow ths of tissue. T h e new’ direct lig h t system , it appears, is w ith o u t these objectionable features. Dr. H u n te r will not p aten t his invention but p ro poses to give it freelv to the wrorld, h o ping th at others will develop and im prove it so th a t finally it will be possible to secure w ith a sim ple $2 outfit pictures as good as those obtained w’ith a $1000 x -ra y m achine.
