Oct. 26, 1883.j 



♦ KNOWLEDGE ♦ 



253 



long a distance as he possibly can, might very likely cause 

 death within a few minutes, where carefully resting his lungs 

 and taking no exercise which could in the slightest degree 

 hasten respiration, would not very obviously encourage the 

 progress of pulmonary mischief. A man with weak arm 

 muscles, again, might easily, by attempting to lift great 

 weights or to sway unwieldy clubs or dumb-bells, so strain 

 and injure the muscles and tendons of his arms, as to 

 weaken himself much more in a few moments than he 

 would by months of laziness with his arms. There is 

 reason in all things, and the wise rule must be obeyed even 

 in things good — Ne quid nimis. But within the limits 

 suggested by reason and moderation, the rules remain 

 sound, Where there is weakness, whether of muscle or 

 organ, there exercise is the right thing ; Where there is stiff- 

 ness, not rest but movement is required. 



The great difference between those still young but 

 wanting in strength or lissomness, and those in advanced 

 life, is of course that in one case exercise may be under- 

 taken with the reasonable hope of increasing strength or 

 activity, in the other the aim is rather to check the changes 

 by which in accordance with natural laws the strength and 

 activity gradually diminish with advancing years. Though, 

 even with men in middle and advanced life we often find that 

 muscles and organs which through disuse have been pre- 

 maturely weakened may bo restored to a degree of vigour 

 much nearer the vigour of the prime of life than is com- 

 monly supposed. We know a man who ten years ago was 

 much weaker and much less active, and in effect was, at 

 least in one sense of the words much older, than he is at 

 the present day. He saw that laziness (bodily laziness at 

 least) was doing more to age him than years ; and liy 

 steady and even active exercise he has been able to throw 

 off the burden of a round dozen of years at least. 



(To he continued.) 



THE CHEMISTRY OF COOKERY. 



By W. Mattieu Williams. 



IX my last I explained the hardening effect of boiling 

 water on meat, and the consequent necessity of keeping 

 down the temperature considcraVily belov,' the boiling-point 

 in order to obtain a tender and full-flavoured stew. Some 

 further explanation is necessary, as it is quite possible to 

 obtain what commonly passes for tenderness by a very 

 flagrant violation of the principles there expounded. This 

 is done on ti large scale and in extreme degree in the pre- 

 paration of ordinary Australian tinned meat. A number 

 of tins are filled with the meat, and soldered down close, all 

 but a small pin-hole. They are then placed in a bath 

 charged with a saline substance, such as cliloridc of zinc, 

 which has a higher boiling-point than water. Tliis is 

 heated up to its boiling-point, and consequently the water 

 which is in the tins with tlu; meat boils vigorously, and a 

 jet of steam mixed with air blows from the pin-hole. When 

 all the air is expelled and the jet is of pure steam only (a 

 difference detected at once by the trained expert), the tin 

 is removed, and a little melted solder skilfully dropped on 

 the hole to seal the tin hermetically. An examination of 

 one of these tins will show this final soldering with — in 

 some — a fiap below to prevent any solder from falling in 

 amongst the meat. Thi^ object of this is to exclude all air, 

 for if only a very small ([uantity remains, oxidation and 

 putrefaction speedily ensues, as shown by a bulging of the 



tins instead of the partial collapse that should occur when 

 the steam condenses, the display of which coUapse is an 

 indication of good quality of the contents. 



By "good quality" I mean good of its kind; but, as 

 everybody knows who has tried beef and mutton thus pre- 

 pared, it is not satisfactory. The preservation from putre- 

 factive decomposition is perfectly successful, and all the 

 original constituents of the meat are there. It is apparently 

 tender, but practicaUy tough — i.e., it falls to pieces at a 

 mere touch of the knife, but these fragments oiler to the 

 teeth a peculiar resistance to proper masticatory commi- 

 nation. I may describe their condition as one of per- 

 tinacious fibrosity. The fibres separate, but there they are 

 as stubborn fibres still. 



This is a very serious matter, for, were it otherwise, the 

 great problem of supplying our dense population with an 

 abundance of cheap animal food would have been solved 

 about twenty years ago. As it is, the plain tinned-meat 

 enterprise has not developed to any important extent 

 beyond aflbrding a variation with salt junk on board ship. 



What is the rationale of this defect? Beyond the 

 general statement that the meat is " overdone," I have met 

 with no attempt at explanation ; but am not, therefore, 

 disposed to give up the riddle without attempting a 

 solution. 



Reverting to what I have already said concerning the 

 action of heat on the constituents of flesh, it is evident 

 that in the first place the long exposure to the boiling- 

 point must harden the albumen. Syntonin, or muscle-fibrin, 

 the material of the ultimate contractile fibres of the muscle, 

 is coagulated by boiling water, and further hardened by con- 

 tinuous boiling, in the same manner as alV)umen. Thus, 

 the muscle fibres themselves and the lubricating liquor* in 

 which they are imbedded must be simultaneously toughened 

 by the method above described, and this explains the 

 pertinacious fibrosity of the result. 



But how is the apparent tenderness, the facile separation 

 of the fibres of the same meat produced 1 A little further 

 examination of the anatomy and chemistry of muscle will, 

 I think, explain this quite satisfactorily. The ultimate 

 fibres of the muscles are enveloped in a very delicate mem- 

 Ijrane : a bundle of these is again enveloped in a somewhat 

 stronger membrane (areolar tissue); and a number of these 

 bundles or fasciculi are further enveloped in a propor- 

 tionally stronger sheath of similar membrane. All these 

 binding membranes are mainly composed of gelatine, or 

 the substance which (as explained in No. •')) produces 

 gelatine when boiled. The boiling that is necessary to 

 drive out all the air from the tins is sufficient to dissolve 

 this, and effect that easy separability of the muscular fibres, 

 or fasciculi of fibres, that gives to such overcooked meat 

 its fictitious tenderness. 



I have entered into these anatomical and chemical 

 details because it is only by understanding them that the 

 difference between true tenderness and spurious tenderness 

 of stewed meat can l>e soundly understood, especially in 

 this country, where stewed meats are despised because 

 scientific stewing is practically and generally an unknown 

 art. Ask an English cook the difleronce between boiled 

 beef or mutton and stewed beef or mutton, and in ninety- 

 nine cases out of a hundred her reply will be to the effect 

 that stewed meat is that which has been boiled or simmered 

 for a longer time than the boiled meat. 



* I have ventnreci to ascribe this lubricating function to the 

 albumen wliicli envelopes the fibres, thou<?h doubtful whether it is 

 quite orthodox to do so. Its identity in composition with the 

 synovi.ll liquor of the joints, and the necessity for such lubricant, 

 justify this supposition. It may act as a nntiient fluid at the same 

 time. 



