the adhesives of the invention comprise a sugar , cross - linked with a polyfunctional acid . the cross - linking is believed to be an acid - catalyzed esterification or etherification , depending on whether the functional group of the polyfunctional acid that enters into the covalent bond with the sugar hydroxyl is the acid moiety or another hydroxyl group . the requisite cross - linking will occur with any sugar having at least two hydroxyls . the preferred sugars are disaccharides , such as sucrose , lactose , maltose and cellobiose . for most applications wherein sucrose is already present as a sweetener , sucrose would be the disaccharide of choice . monosaccharides contemplated for use in the invention include 5 - and 6 - carbon aldoses and ketoses , such as glucose , galactose , fructose , mannose , arabinose , etc ., with glucose and fructose usually being preferred . polyhydroxy alcohols , such as sorbitol , can also be used . the polyfunctional acids for use in cross - linking the sugars will most typically be organic acids falling into two main categories : polycarboxylic acids and hydroxycarboxylic acids . typical organic acids useful in the method of the invention include citric acid , malic acid , tartaric acid , fumaric acid , glycolic acid , lactic acid and mandelic acid . in addition to the aforementioned organic acids , phosphoric acid is also useful for cross - linking the aforementioned sugars . in the method of preparing the subject adhesives , the sugar is combined with , and preferably dissolved in , water ; and then an aqueous solution of the acid is added to the aqueous sugar . the molar ratio of sugar to water in the initial reaction mixture should be within the range of 1 : 20 to 1 : 60 , with a preferred ratio of about 1 : 30 to about 1 : 50 , and a most preferred ratio of about 1 : 40 . the level of acid compound in the initial reaction mixture will typically be in the range of about 5 - 14 % by weight , with a preferred level of 8 - 11 % by weight . the acidified sugar mixture is heated to a boil and stirred until the desired level of cross - linking has occurred . completion of the reaction is gaged by dropping a drop of the reaction mixture into a beaker of water . the point in the reaction at which the drop retains its shape signals that sufficient cross - linking has occurred and the reaction is complete . at this point , the reaction mixture has a temperature of approximately 128 ° c . and flows easily . the hot reaction mixture is - useful as an adhesive and could be directly applied to the surface or surfaces that are to be bonded together . as the reaction mixture cools , it hardens to a sticky , substantially nonflowable , mass at room temperature ( 25 ° c .). by “ nonflowable ” it is meant that the adhesive material cannot be poured from a beaker ; and when deformed , for example with a stirring rod , will not resume its original shape within the time period of an hour . the adhesives of this invention will typically not flow until they are raised to a temperature exceeding 40 ° c . at 61 ° c ., the adhesives are characterized by a gardner bubble viscosity number within the range of 8 . 3 to 8 . 7 , with a preferred value of 8 . 5 . at 71 ° c ., they are characterized by a gardner bubble viscosity number within the range of 6 . 6 to 6 . 9 , with a preferred value of 6 . 8 . prior to use , the cooled adhesives may be reheated in any manner , such as over direct heat or in a microwave oven , to restore them to a flowable state for facile application to a surface to be bonded . a preferred temperature for applying the adhesives in a flowable state is in the range of about 85 - 95 ° c ., and more preferably about 90 ° c . the adhesives may be reheated and cooled through several cycles without reduction of the adhesive properties , provided that care is taken not to drive off a significant amount of the bound water . for this reason , it is best not to bring the adhesive to boiling during the reheating step . the softened material may be applied to the working surface by any conventional means such as dabbing , rolling , spreading , or dripping . the material may be applied to only one , or to both surfaces to be bonded together . the bonding is immediate , without the need for clamping pressure or prolonged set time . of course , the adherence of the two surfaces to one another will be enhanced as the adhesive cools and becomes less flowable . the adhesives of the invention are useful for bonding a vast array of materials , including without limitation , wood , metal , coated metal , cloth , leather , glass , plastic , paper , food products and the like . they are designed to be releasable upon being weakened ( e . g . dissolved ) in water or other aqueous solvent . for example , the adhesive could be used to temporarily bond a novelty item to the inner surface of a beverage container during the filling stage , and then release the novelty item into the beverage after the container is sealed . see , for example , u . s . pat . nos . 5 , 819 , 979 and 5 , 244 , 112 , both herein incorporated by reference , disclosing the need for an adhesive that will temporarily fix a buoyant member to the inner surface of a beverage container during the filling and seaming processes . likewise , the adhesive could be used to temporarily retain a label to the inner surface of a clear liquid container until after the container is filled . for example , an adhesive bond covering an area of 0 . 25 cm 2 will dissolve in water in approximately 15 - 30 minutes . for some applications , it may be desirable to formulate the adhesive so as to maintain the bond for longer periods , such as for 60 to 90 minutes . acid ( 9 % by weight ) was dissolved in 10 moles water and added to 0 . 5 moles sucrose ( mw = 342 . 30 ) in 10 moles water in a porcelain cup . the mixture was heated over direct heat to boiling , and held at boiling until a sample drop of the reaction liquid would retain its shape when dropped into a full beaker of water . the temperature of the reaction mixture at this stage was approximately 128 ° c . the mixture was cooled and stored at room temperature . to test the ability of the adhesive to bond polypropylene plastic to a lacquered aluminum surface , the adhesive was first softened in a microwave oven by heating for 20 - 25 seconds to a temperature of approximately 75 ° c . a drop of the hot adhesive was then applied with a stirring rod between the two materials , and the materials were pressed together with moderate finger pressure to spread the adhesive over a 0 . 25 cm 2 area . the adhesive was allowed to cool and gel . its strength was subjectively evaluated by peeling the plastic and coated aluminum apart from one corner , and rating the strength of the bond as nil , very weak , weak , medium or strong . a second sample of polypropylene plastic bonded to a lacquered aluminum surface was prepared as described above . the releasability of the adhesive was evaluated by submerging the sample in a beaker of water with the plastic surface up and the aluminum surface down . the time for the adhesive to dissolve as indicated . by the plastic member floating to the surface of the water was recorded . the results are given in table 1 , below . the resiliency of the adhesives of this invention to withstand multiple heating and cooling cycles was evaluated . a mixture of citric acid in water ( 15 g in 25 ml water ) was added to 150 g sucrose followed by the addition of 150 ml water . the mixture was heated according to the procedure described in example 1 , and the resultant cross - linked product was divided into two beakers and allowed to cool to room temperature . one beaker was heated three times in a microwave oven for 25 seconds each time , and allowed to cool for 20 minutes to room temperature between each heating cycle . maximum temperatures ranged from 90 - 97 ° c . the other was heated three times in a microwave oven for a preset time of 45 seconds , and allowed to cool for 20 minutes to room temperature between each heating cycle . maximum temperatures ranged from 101 - 111 ° c . in the second and third heating cycles , boiling occurred at 35 seconds , and the heating was immediately terminated to prevent additional loss of water . based on these trials , it was determined that the preferred temperature of reheating should not exceed about 95 ° c . the results are given in the last column of table 1 , below . acid ( 15 g ) was dissolved in 25 ml water and added to 150 g sugar in a porcelain cup , followed by the addition of 150 g water . the mixture was heated over direct heat to boiling , and held at boiling until a sample drop of the reaction liquid would retain its shape when dropped into a full beaker of water . the temperature of the reaction mixture at this stage varied from about 102 ° c . to about 110 ° c . the mixture was cooled and stored in a refrigerator . the results are reported in table 2 , below .