The Art of Preserving All Kinds of Animal and Vegetable Substances for Several Years, 2nd ed.

My Board of Arts and Manufactures1 has reported to me, Sir, the examination it has made of your process for the preservation of fruits, vegetables, meat, soup, milk, &c. and from that report no doubt can be entertained of the success of such process. As the preservation of animal and vegetable substances may be of the utmost utility in Sea-voyages, in hospitals and domestic economy, I deem your discovery worthy an especial mark of the good will of the government. I have in consequence acceded to the recommendation made me by my council to grant you a recompence of 12,000 francs.2 In so doing I had in view the assigning you the reward due to the inventors of useful processes, and also the indemnifying you for the expences you have been obliged to incur, either in the forming your establishment or in the experiments necessary to establish the success of your process. You shall be immediately informed when you may repair to the public treasury and receive the 12,000 francs.

It appears to me of importance, Sir, that you should spread the knowledge of your preserving process. I desire, therefore, that agreeably to your own proposal, you will digest a detailed and exact description of your process. This description, which you will remit to my Board of Arts and Manufactures, shall be printed at your expence, after it shall have been examined. You will then transmit me 200 copies. The transmission of these copies being the only condition I impose on you for the payment of the 12,000 francs, I doubt not you will hasten to fulfil it. I desire, Sir, you will acknowledge the receipt of my letter.

The undersigned Members of the Board of Arts and Manufactures attached to the Minister of the Interior, being required by his Excellency to examine the description of the process of Mr. Appert for the preservation of alimentary substance, certify that the details it contains, as well on the mode of carrying on the process as on the results, are exactly conformable to the various experiments which Mr. Appert has made before them, by order of his Excellency.

Paris, 19th April 1810.

Copy of a Letter written to General Caffarelli, Maritime Prefect at Brest, by the Council of Health, dated Brumaire, year 12.

The provisions prepared according to the process of Citizen Appert and sent to this port by the Minister of Marine, have, after lying in the roads three months, been found in the following condition.

The broth or soup (bouillon) in bottles was good; the bouillon with a bouilli in a vessel apart was also good, but weak; the bouilli itself was very eatable.

The beans and green peas, prepared both with meat and vegetable soup, had all the freshness and flavour of recently gathered vegetables.

True Copy.

§ I

All the expedients hitherto made use of for preserving alimentary and medicinal substances, may be reduced to two principal methods; that of dessication; and that of mingling, in greater or less quantities, a foreign substance for the purpose of impeding fermentation or putrefaction.

It is by the former of these methods that we are furnished with smoaked and hung meat, dried fish, fruits, and vegetables. By the latter, we obtain fruits and other vegetable substances preserved in sugar, the juices and decoctions of plants reduced to syrups and essences, all kinds of pickles, salted meat and vegetables. But each of these modes has its peculiar inconveniences. Dessication takes away the odour, changes the taste of the juices, and hardens the fibrous or pulpy matter (the porenchyma).

Sugar, from the strength of its own flavour, conceals and destroys in part other flavours, even that, the enjoyment of which we wish to preserve, such as the pleasant acidity of many fruits. A second inconvenience is this, that a large quantity of sugar is required in order to preserve a small quantity of some other vegetable matter; and hence the use of it is not only very costly, but even in many cases pernicious. Thus the juices of certain plants cannot be reduced to a syrup or essence, but by means of nearly double the quantity of sugar. It results from this, that those syrups or essences contain much more sugar than any medicinal substance, and that most frequently the sugar counteracts the operation of the medicine, and is hurtful to the patient.

Salt communicates an unpleasant acerbity to substances, hardens the animal fibre, and renders it difficult of digestion. It contracts the animal parenchyma.3 On the other hand, as it is indispensable to remove, by means of water, the greater part of the salt employed; almost all the principles which are soluble in cold water, are lost when the salt is taken away: there remains nothing but the fibrous matter, or parenchyma; and even that, as has been said, undergoes a change.

Vinegar can seldom be made use of, but in the preparation of certain articles for seasoning.

I shall not enter into any details concerning what has been said and published on the art of preserving alimentary substances. I shall only observe, that as far as my knowledge extends, no author, either ancient or modern, has ever pointed out, or even led to the suspicion, of the principle which is the basis of the method I propose.

It is known, how much, within a certain period, the public attention, both at Paris and in the departments, has been directed towards the means of diminishing the consumption of sugar, by supplying its place by the use of various extracts, or essences, of indigenous substances. The government, whose philanthropic views are turned towards all useful objects, does not cease to invite all those who pursue the arts and sciences, to investigate the means of drawing the utmost advantage from the productions of our soil, in order to develope, to the utmost, our agriculture and manufactures, and so diminish the consumption of foreign commodities.

In order to attain the same end, the Society for the Promotion of National Industry4 stimulates, by the offer of flattering rewards, all those whose talents and labours are directed towards discoveries, from which the nation and humanity may draw substantial benefits. Animated by this laudable zeal, the Agricultural Society, by its resolution of the 21st of June 1809, and its official notification of it, the 15th of the July following, made an appeal to the whole nation, in order to collect all the information and documents which might contribute to the composition of a work on the art of preserving, by the best possible means, every kind of alimentary substance.

It was after invitations of so great weight, that I resolved to make known a method of effecting this object, of great facility in the execution, and at the same time very cheap, and which, by the extension it admits of, may afford numerous advantages to society.

This method is not a vain theory. It is the fruit of reflection, investigation, long attention, and numerous experiments, the results of which, for more than ten years, have been so surprising, that notwithstanding the proof acquired by repeated practice, that provisions may be preserved two, three, and six years, there are many persons who still refuse to credit the fact.

Brought up to the business of preserving alimentary substance by the received methods; having spent my days in the pantries, the breweries, store-houses, and cellars of Champagne, as well as in the shops, manufactories, and warehouses of confectioners, distillers, and grocers; accustomed to superintend establishments of this kind for forty-five years, I have been able to avail myself, in my process, of a number of advantages, which the greater number of those persons have not possessed, who have devoted themselves to the art of preserving provisions.

I owe to my extensive practice, and more especially to my long perseverance, the conviction:

1st. That fire has the peculiar property, not only of changing the combination of the constituent parts of vegetable and animal productions, but also of retarding, for many years at least, if not of destroying, the natural tendency of those same productions to decomposition.

2d. That the application of fire in a manner variously adapted to various substances, after having with the utmost care and as completely as possible, deprived them of all contact with the air, effects a perfect preservation of those same productions, with all their natural qualities.

Before I state the details of my process, I ought to observe that it consists principally,

1st. In inclosing in bottles the substances to be preserved.

2d. In corking the bottles with the utmost care; for it is chiefly on the corking that the success of the process depends.

3d. In submitting these inclosed substances to the action of boiling water in a water-bath (BALNEUM MARIAE), for a greater or less length of time, according to their nature, and in the manner pointed out with respect to each several kind of substance.

4th. In withdrawing the bottles from the water-bath at the period described.

§ II.

Description of my Rooms set apart for carrying on the Process on a large Scale. 5

My laboratory consists of four apartments. The first of these is furnished with all kinds of kitchen utensils, stoves, and other apparatus, necessary for dressing the animal substances to be preserved, as well as with a kettle for broth, gravy, &c. containing 180 French pints, raised on brick work. This kettle is provided with a pot to be put within it, pierced with holes like a skimmer, with divisions for holding various kinds of meat and poultry. This pot can be put into and taken out of the kettle with ease. The kettle is provided with a wide cock, to which is fitted, within, a little rose, like that of a watering-pot, covered with a piece of boulting-cloth. In this way I can procure broth or gravy quite clear, and ready to be put into bottles.

The second apartment is appropriated to the preparing of milk, cream, and whey.

The third is used for corking and tying the bottles and vessels, and putting them into bags.

The fourth is furnished with three large copper boilers, placed upon stones raised on brick work. These boilers are all furnished with a stout lid, fitted, to rest upon the vessels within. Each boiler is furnished with a wide cock below, in order to let out the water at a proper time. These large boilers are destined to receive, generally, all the objects intended to be preserved, in order to apply the action of heat to them in a suitable manner; and thus they constitute so many water-baths.6

The utensils which furnish the third apartment for the preparatory process consist of

1. Rows of bottle-racks round the room.

2. A reel for the iron wire, to be used for binding the necks of the bottles and other vessels. (Fig. 1.)

3. Shears and pincers for tying on the corks. (Fig. 6.)

4. Machine for twisting the iron-wire after it has been divided and cut to a proper length. (Fig. 2.)

5. Two instruments forming a lever, and used for compressing, and as it were biting the corks. (Fig. 3.)

6. A bottle-boot or block, standing on three legs, and provided with a strong bat for corking. (Fig. 5.)

7. A stool standing on five legs, for tying on the corks. (Fig. 4.)

8. A sufficient quantity of linen bags, for covering the bottles and other vessels.

9. Two stools covered with leather and stuffed with hay, in order to shake the bottles upon them, and in that way force a greater number of peas and other small substances into the bottles.

10. A press for the juice of plants, fruits, and herbs; with pans, vessels, sieves, and every thing else that belongs to it.

Besides my laboratory, consisting of these articles, I have fitted up three apartments.

The first, for preparing vegetables: it is furnished with dressers all round.

The second, for storing up and preparing all kinds of fruit.

The third is a cellar, furnished with bottle racks, for rinsing and setting by the bottles and other vessels, as in a store-house.

I have the precaution to keep the bottles and other vessels I may want, ready rinsed at hand. I am also supplied with an assortment of corks, compressed and bit in the instrument already described. When every preparation is thus made, the process is half done.

The principle by which all alimentary substances are preserved and kept fresh, is invariable in its effects. The result in particular experiments, depends upon the fitness of each individual application of the principle to the substance which is to be preserved, according to its peculiar qualities; but in every case, the exclusion of air is a precaution of the utmost importance to the success of the operation: and in order to deprive alimentary substances of contact with the air, a perfect knowledge of bottles and the vessels to be used, of corks and corking, is requisite.

§ III.

Of Bottles and Vessels

I chose glass, as being the matter most impenetrable by air, and have not ventured to make any experiment with a vessel made of any other substance. The ordinary bottles have generally necks too small and ill made; they are also too weak to resist the blows from the bat and the action of the fire: I, therefore, caused bottles to be made for my especial use, with wider necks, and those necks made with a projecting rim, or ring, on the interior surface, placed below, and resembling, in form, the rim which is at the top of the exterior surface of the necks of bottles. My object was, that when the cork had been forced into the neck of the bottle, three-fourths of its length, in the manner already described, it should be compressed in the middle. In this manner the bottle is perfectly corked on the outside as well as within. It thus opposes an obstacle to the swelling, or expansion, which arises from the operation of heat upon the substance enclosed within the bottle. This mode of forming the neck of the bottle is so much the more indispensable, as I have repeatedly known the swelling to be so strong, as to push out corks of three or four lines in length, though confined by two iron wires crossed. The bottles and vessels should be made of a tough substance [de matière liante], the former having the weight of twenty-five or twenty-six ounces for each litre7 that the bottle contains. The glass ought to be of equal thickness in every part, or it is liable to break in the water-bath. The form of the Champagne bottle is most convenient; it is the handsomest as well as the strongest, and is of the best shape for packing up.

§ IV.

Of Corks

Economy in corks is generally very unwise, as in order to save a very trifle in the price of cork, a risk is incurred of losing the valuable commodity it is intended to preserve. As corking is made use of in order to preserve and meliorate certain articles, by depriving them of all contact with the air, too much attention cannot be given to the good quality of the cork, which should be of eighteen or twenty lines in length and of the finest quality. Experience has so fully satisfied me on this point, that I never make use of any but superfine corks: these are, in the end, the cheapest. I further take the precaution of compressing, and, as it were, biting the cork, three-fourths of its length, by means of the instrument already described (fig. 3), beginning at the small end. The cork is rendered more supple; the pores of the cork are brought closer; it is somewhat lengthened, and its thickness is so much diminished at the extremity which is put into the mouth of the bottle, that a large cork may be made to enter a very moderate opening. The action of the heat within the vessel is such, that the cork swells within, and the corking is thus rendered perfect.

§ V.

Of Corking

After what has been just said, the absolute necessity will be apparent of having good bottles, with a projecting rim of equal thickness all round within the neck. Excellent superfine corks are also indispensable, which have been compressed in the instrument three quarters of their length.

Before I cork, I take care that the bottles containing liquor are filled only up to within three inches of the outer rim, lest they should burst from the bubbling and swelling occasioned by the application of heat to the water. When the bottles contain vegetables, fruit, &c. they may be filled up to within two inches of the rim.

I place the full bottle upon the bottle-boot already mentioned, before which I seat myself. This apparatus is to be supplied with a strong wooden bat, a small pot full of water, and a sharp knife, greased with a little suet or soap, for cutting off the tops of the corks, which ought never to be raised much above the head of the bottles. These arrangements being made, I place the bottle-boot between my legs, and taking a cork of fit size, I dip one half of it into the little pot of water, in order to facilitate its entrance; and having wiped the end, I then put it to the mouth of the bottle, at the same time turning it round. I hold it in this position with my left hand, which I keep steady, that the bottle may stand upright. I take the bat in my right hand, in order to drive in the cork by force of blows.

When I find, at the first or second blow of the bat, that the cork has somewhat entered, I take my hand from the cork in order to hold with it the neck of the bottle, which I fix firmly and upright upon the bottle-boot; and by dint of repeated blows, I continue to drive in my cork three-fourths of its length. The quarter of the cork which remains above the bottle, after having refused to yield any further to the redoubled blows of the bat, assures me, in the first place, that the bottle is completely corked, and this same residue serves also to hold the double crossed iron wire which is necessary to bind fast the cork, that it may be able to resist the action of heat on the water-bath. I must repeat again, that too much attention cannot be given to the corking: no circumstance however minute ought to be neglected, in order to effect the rigorous exclusion of the air from the substance to be preserved; air being a most destructive agent, and the one which is most sedulously to be counteracted in the course of the process.8