[1]Patented Nov. 3. 1942 2 1 3 0 0 @ 7 7 7 UNITED STATES. PATENT OFFICE 2,300,777 METHOD OF G&MING FRUILT Burton C. Coons, San Jose, CaRf., asdgnor to Food Machinery Corporation, San Jose, CaRf., a corporation of Delaware No Drawing. Application October 17, 1940, Serial No. 361,603 9 CLdms. (CL 146-17) The present invention appertains to a method machines in which the cherries are held in a cenof grading fruit such as maraschino style cherries or the Uke and relates primarily to a method of separating pitted from unpitted fruit, and of quality grading the pitted fruit. In the preparation of wholemaraschino cherries it is customary to treat the unpitted fruit by soaking it in a brine solution, and then remove the pits. In commercial practice cherries are commonly 10 pitted by one of two well-known methods. One of these consists in niaking an incision at the stem end of the fruit and extracting the pit therethrough by means of tongs or pincers. The other, and perhaps more common method, is to 15 force the pit through the body of the cherry by means of a punch. T-n either case an opening is formed in the fruit by the extraction of the pit, and this opening communicates with an air pcicket in the center of- the fruit previously Oc- 20 cupied by the Pit. It has been discovered, not only that pitted and unpitted cherries have a different specific gravity and may be separted in a liquid of proper density, . but also that by closing the opening through 25 which the pit has been extracted, a substantially sealed air pocket is formed within the center of the fruit previously occupied by the pit, and an additional separation of the pitted fruit into grades of different quality may be obtained. 30 It Is therefore one of the objects of the present inv6ntion to provide a method of separating pitt.ed and unpitted cherries and of quality-grading the pitted fruft. Another object is to provide a method of sepa- 35 rating pitted cherries containing a substantially closed air pocket from cherries which d6 not have such closed air.pocket. A further objeci Is to provide a method of separating pitted cherries without a closed air 40 pocket -from unpitted cherries. - Another object is to provide a method of separating unpitted cherries from pitted cherries irrespective of the quality of the pitted cherries. Another objeet is to provide a method of qual- 45 ity-grading of cherries and subsequently separating the pitted and unpitted cherries. Other objects, uses, adaptations and advantages of the present invention will become apparent from the following description, wherein particu- 50 lar reference is being made to the separation of pitted and unpitted'mara-schino cherries or similar fruits. in commercial praketice the pitting of cherries is usuany peilormed mechanically by pitting 55 tered position with respect to a pitting tool which enters the fruit and removes the Pit. In one type of machine it is customary to extract the pit through the stem end of the fruit by tongs or the like and to form, preparatory to the extraction of the pit, radial incisions at the stem end of the fruit which extend through the meat toward the pit to facilitate the removal of the pit without tearing away parts of the flesh, by permitting an outward bending of the meat and skin portions at the stem end of the fruit during the extracting operation. in another type of pitting machine, the pitting tool is in the form of a punch which enters through one end of the fruit, forcing the pit through the flesh of the fruit without previous incision thereof. In this'instance the pit itself cuts and bends the meat and skin portion of the cherry as it emerges from the fruit. While these cherry pitting machine@ are ordinarfly verysatisfactory in their operation, it occasionally happens, from any one of various causes, that the pitting tool fouls or misses a pit, which therefore remains within the fruit. These unpitted cherries are very difficult to detect and are obviously undesired in the flnished product. Occasionally also fragments of flesh or skin may be torn from the fruit diiring the pitting thereof, and such cherries are therefore not quite satisfactory as a first grade product. A grading of the fruit to separate the pitted and unpitted cherries, and to separate the pitted cherries of different qualities, is therefore highly desirable. In carrying out the process of the present invention, the meat and skin portions of the pitted cherry which have been bent and dislocated in the region of the wound formed by the extraction of the pit are flrst pressed,back into place to close the wound, so that a sealed, or substan. tiauy sealed, air pocket is formed in the center of the fruit previously occupied by the pit. The closing of the wound of the fruit may be done manually by pressing the meat portions, with the fmger, back into the center of the fruit, or mechanically as by a presser foot or any other type of tucking mechanism pressing upon the wound from which th6 Pit emerged. If, however, portions of the meat or skin of the cherry have been' tGm away in the region af the wound during the extraction of the pit, the cherries can not be sufficiently closed to forin a @ubstantially sealed air pocket within the center of the fruit but will remain open. Thereupon, the mixed mass of pitted and un-
[2]Pitted fruit Is placed in a suit-ible grading solution to separate the pitted and closed cherries from the unpitted cherries and the pitted but open fruit. The specific gravity of this solution is such that both the unpitted cherries as weH as the pitted but open cherries (I. e. those which do not contain a sealed air pocket) wlU sink therein while the pitted and closed cherries (I. e. those @hich . contain a substantially sealed air pocket) will float. For separating maraschino cherries the customary pickling solution in which the cherries are stored to preserve the same may be satisfactoril@ used as grading solution. However, any other suitable brlne or sugar solution may be employed provlded that the speciflc gravity of such solution is lower than the speciflc gravity of the pitted cherries. The flotation of the cherries in the solution above referred to takes place by reason of the buoyant action of the entrapped air within the fruit. Therefore the cherries which contain a closed or substantially closed air pocket wiU float while those cherries which do not contain a closed or substantially closed air pocket, as well as fragments of cherries and unpitted cherries will immediately sink therein. It w!U be obvious that the pitted but open cherries cannot float in this solution as the air pocket has not been properly closed and the air will therefore escape from the pocket previously occupied by the pit upon submersion of the fruit. F'rom the above it will therefore be seen that a perfect separation of the pitted and closed cherries from the remaining cherries is accomplished, and the floating or flrstgrade cherries may be collected from the surface of th6 grading solution in any desired manner. The pitted but open cherries and the unpitted cherries, all of which sink in the grading solution, are thereupon removed from the same and may be placed in another more concent@ated grading solution having a specifle gravity slightly above the specifle gravity of the pitted but open cherries, but not of sufficient density to float or suspend the unpitted cherries. When the pitted but open cherries and the unpitted cherries are placed in this solution, the pitted cherries will float and the unpitted cherries will sink. Any suitable brine or sugar solution may be employed for carrying out the separation last referred to; however, the density of this solution must be slightly above the speciflc gravity of the pitted cherries and below the speciflc gravity of the unpitted cherries so that a separation between the pitted but open cherries, fragments of cherries and the unpitted cherries is obtained. During t'his step In the method of the present invention, the unpitted cherries which sink, and the pitted but open cherries or fragments thereof which float, may be separa@tely collected in any desired manner. The pitted but operl cherries may be packed or further treated as second grade fruit, which still has a considerable marketable value. The unpitted cherries may be retumed to the pitting machine for removal of the pits thereof and regraded after such pitting operation in the same"manner as described hereinabove. While in the foregoing reference has been, made to the grading of maraschino cherries, it has to be understood that the method of the present invention is equally well adaptable for grading fresh cherries. If fresh whole cherries are to be SeParated in accordance with the method of the in2,300,777 -solution, or t he like which does not affect the taste or condition of the fruit may be employed. The specific gravlty of these solutions must, of course, be of the same density as set forth herein for carrying out the flrst and second steps of the separation in a manner as hereinabove stated. The strength of the solutions employed in accordance with the teachings of the present Invention may vary depending upon the sugar conio tent of the cherries or any other factors which ma:@ vary the specifle gravity of the cherries. However, the specifle gravity of the cherries and the density of the solutions employed should always be maintained in the same relation as set 15 forth herein. Wbile hereinabove reference has been made to a two-step. separation method, it will be apparent that If only a separation between pitted and unpitted cherries Js desired, regardless of )o the quality of the pitted cherries, or If only a separation of the pitted and closed cherries from the remaining fruit Is desired, the flrst or second step, respectiveiy, of the present method may be omitted. Depending upon the amount of entrapped air within the pitted fruit, even water m@Ly serve as a grading solution for carrying out the flrst step@of grading of the method explained herein, and in this respect the present invention is not 30 limited to solutions heavier than water. It has been found that during the flrst step of separation of the method of the present invention, the air entrapped and enclosed within the Pitted cherries has a tendency to escape from 35 the pocket within the fruit In case the same is not completely sealed after the pitting of the fruit. This tendency, however, is sufficiently retarded when a solution heavier than water is used during the first step of separation of the 40 instant invention, so that the cherries will float aconsiderable length of time, within which the same may be conveniently separated andgrouped. If water is used the air will escape more rapidly from the not completely closed pockets in the 4,-) center of the cherries when the same are dropped In the grading solution. This appears to be due to the fact that the cherries will momentarily sink deeper In water than in a solution of greater density when they are dropped therein, and the 50 buoyancy force acting upon the enclosed air tending to remove the same will be, during such time, comparatively larger in water than in a heavier liquid. Therefore, if water is used as a grading solution for carrying out the first step of sepa5-5 ration of the fruit the floating cherries must be collected more rapidly from the grading solution, because some of the cherries with a substantially but not compliately sealed air pocket will only float for a comparatively short time. 60 It will be undei@stood that while the process of the present invention has been described as employed for grading cherries, it is contemplated that it may be used for grading other drupaceous 65 fruits and the term "cherries" as used in the claims is intended to be inclusive of such other f ruits. While the present invention has been described in considerable detail, it is not desired to 70 hmit the same to the specific mode and practice of the method as disclosed herein, nor the specifle type of grading solutions set forth in t.-ie above, as many changes or modifications may be m@de within the purview of the appended claiins. stant invention, any sWtabIe brine solution, sugar 75 Having thus described the present invention,
[3]what is claimed as new and desired to pro'tect by tJ. S.
