SYN′COPE. See Fainting.
SYR′UP. Syn. Sirup, Sirop; Syrupus, L. A saturated, or nearly saturated, solution of sugar in water, either simple, flavoured, or medicated.
In the preparation of syrups care should be taken to employ the best refined sugar, and either distilled water or filtered rain water; by which they will be rendered much less liable to spontaneous decomposition, and will be perfectly transparent, without the trouble of clarification. When inferior sugar is employed, clarification is always necessary. This is best done by dissolving the sugar in the water, or other aqueous menstruum, in the cold, and then beating up a little of the cold syrup with some white of egg, and an ounce or two of cold water, until the mixture froths well; this must be added to the syrup in the boiler, and the whole ‘whisked up’ to a good froth; heat should now be applied, and the scum which forms removed from time to time with a clean ‘skimmer.’ As soon as the syrup begins to slightly simmer it must be removed from the fire, and allowed to stand until it has cooled a little, when it should be again skimmed, if necessary, and then passed through clean flannel. When vegetable infusions or solutions enter into the composition of syrups, they should be rendered perfectly transparent by filtration or clarification, before being added to the sugar.
M. Magnes-Lahens[218] describes below a process for the clarification of syrups, the originator of which was M. Demarest, a pharmacien.
The process is as follows:—White unsized paper is beaten up into a pulp with a portion of the syrup, and then mixed with the bulk. The proportion of paper should be one gram to every litre of syrup; and the latter should be maintained at a temperature of 35° to 40° C.
[218] ‘Germ. Pharm. Chem.,’ 4th Series, xv, 140 (‘Year Book, Phar.,’ 1872).
A filter of moleskin capable of holding about one third of the volume of the syrup, and having the form of an inverted sugar-loaf, is supported over a suitable receptacle; the syrup with the pulp is poured rapidly into it, so as to fill it as quickly as possible; and the filter is kept full so long as any of the syrup remains. When the greater part has run through, and but little remains in the filter, and consequently the ‘felting’ of the paper pulp is complete, the syrup which has already run through, is again poured into the filter. The liquid which now passes is perfectly bright, and may be collected. In pouring the syrup into the filter, the stream should be directed into the middle, and not upon the sides, so as to avoid disarranging the felt, which would interfere with the success of the operation.
The author very strongly recommends this method for the clarification of all kinds of syrups; its advantages being that it results in a perfectly limpid liquid, and that it involves neither trouble nor loss of time or material. He states that in 4 or 5 hours, with a filter of 8 litres in capacity, 24 litres of syrup may be clarified.
The small quantity of syrup retained in the filter and pulp, may be recovered by pouring on a sufficient quantity of warm water, pressing strongly, evaporating the liquid to a syrupy consistence, beating up with a little paper pulp, and passing, it again through a small filter.
The proper quantity of sugar for syrups will, in general, be found to be 2 lbs. (avoir.) to every imperial pint of water or thin aqueous fluid. These proportions, allowing for the water that is lost by evaporation during the process, are those best calculated to produce a syrup of the proper consistence, and possessing good ‘keeping qualities.’ They closely correspond to those recommended by Guibourt for the production of a perfect syrup, which, he says, consists of 30 parts of sugar to 16 parts of water.