11  EP 3 800 019 A1 12  peller10 has been shownto cause less interference with food products(e.g.,potatoes)and the resulting chips dur- ing slicing. FIGS. 13a, 13b and 13c help to illustrate the degree of interference forthree differentknife bevel con- figurations. The views of FIGS. 13a, 13b and 13c are from the frame ofreferenceof a potato immediately prior to encountering the knife edge. The "interference" pre- sented by the bevel on the knife edge is shown on FIGS. 13a through 13cin the respective connected detailviews B, D, and F. As used herein, interference refers to the extent to which any portion of the knife 14 intrudes on the radial path of the potato during slicing as a result of the portionprotruding farthertoward the impeller10 than the knifetip 14a oftheknife 14.Such a protrudingportion, referred to herein asthe radiallyinnermostlocalextremity 14b of the knife 14, is believed to cause the slice to have a decreasing taper,sometimesto zerothickness.As dis- cussed below, protrusion of the radially innermost local extremity 14b of the knife 14 is preferably, and in some cases must be, limited to less than 0.004 inch (about 0.1 mm) to avoid excessive slice taper. 5 10 15 20 20 degrees,and more preferably about12to 15 degrees. The impeller paddles 16 may be equipped with means for absorbing impacts, for example, a gel-facing or an impact absorbing material 56 such as a compressible hose orother material thatdeforms underimpact asrep- resented in FIG. 14, to gently catch and hold food prod- ucts during slicing. The impact absorbing material or coating may cover the entire impeller paddle 16 of a por- tion thereof. Alternatively, the food products could be ra- dially accelerated until their radial velocity more closely matches the radial velocity of the impeller paddles 16 to reduce the inevitable product damage resulting from near-stationary food product being impacted by the ro- tating impeller paddles 16. [0031] Based onthese sameinvestigations,itwas also identified that slices with inconsistent slice thickness came in groups, indicating that thickness inconsistency was partially related to impeller10 contactwith the prod- uct. It wasdetermined thata solid planarimpeller paddle surface, when pushing against a asymmetric product, where contact is not in line with the product’s center of mass, can generate a torque on the product. This result- ant torque can disturb the position of the product during the slicing process resulting in inconsistent slice thick- ness as the slice progresses. In one embodiment, the impeller 10 can be configured with deformable paddle surfaces which can conform to the shape of the product, thusspreading outthe forces associated with the contact surface, which results in lower torque generation and more uniform slice thickness. 25 30 [0029] As seen by a comparison of FIGS. 13a, 13b, and 13c, a double bevel shown in FIG. 13a represents a particular degree of interference as evidenced by a di- mension ("d$_{i}$") between the knife tip 14a and the radially innermost local extremity 14B of the knife 14. FIG. 13b shows an inward biased bevelconfiguration (bevelfacing the impeller 10) that presents greater interference than that of FIG. 13a, whereas FIG. 13c shows an outward biased bevel configuration (bevel facing away from the impeller 10) that presents much less interference than that of FIG. 13a. During investigations pertaining the is- sueofinterference,knives withinterferences ofless than 0.004 inch (about 0.1 mm), more preferably less than less than 0.003 inch(about0.08mm)and mostpreferably less than 0.001 inch (about 0.025 mm) achieved with biased bevels having a grind angle of between about 7 and 11 degrees were determined to provide improved slice quality, whereas interferences exceeding 0.004 inch resulted in unacceptable slice quality. 35 40 [0032] During the development of the present inven- tion,shoes 22 with andwithout gate insertstrips23 were also investigated (FIG. 15). A gate insert strip 23 is the lastpartofa slicing shoe 22 contacted bythe foodproduct prior to engaging the knife 14 mounted on the immedi- ately trailing shoe 22. As was described in reference to FIGS. 1 through 4, the gate insert strip 23 at the end of a shoe 22 is typically adjustable for slice thickness. A shoe 22 comprising the gate insert strips often has the capability to "true up" the end of the s hoe 22 to maintain slice quality after wearing. In contrast, a shoe 22 without the gateinsert strips23 extends alltheway to the tip 14a of the knife 14. Often for potato slicing, shoes 22 have flat gates to minimize damage to the knife 14 and knife holder 27 from rocks, sand, and other debris. However, during testing to produce potato chips having large-am- plitude corrugations of the type represented in FIG. 9, it was determined that phase misalignment occurred in consecutive slices produced with shoes 22 having flat gates. Phase alignment is critical when slicing a dehy- drated product, for example, fried or baked potato chips, because the thin-thick cross section of a misaligned phase (FIG. 16) results in over- and under-cooking of a single chip with corresponding results in burnt flavor, breakage, and/or spoilage. [0030] During investigations leading to the present in- vention,itwas noticed thatthe food productwas sustain- ing flesh impact damage resulting from contact with the rotating impeller paddles 16. This food product damage leads to finished product quality reductions, additional waste generation, and additional starch release,allneg- ative consequences. During development, positive pad- dle angles of between 5 to 35 degrees were determined to reduce damage to the food product. Therefore, ac- cording to another aspect of the invention, the impeller paddles 16are preferablyinclined atapositive angle (the terms "positive" and "negative" in relation to paddle in- clination are defined in FIG. 4), ranging from as little as 5 degrees to about 35 degrees to the radials of the im- peller 10. One embodiment positions the paddle angle atabout13.5 degrees,thoughitisforeseeablethatother paddle angles could have different benefits. More pref- erably, the paddles are at a positive angle of about 8 to 45 50 55 [0033] In response, corrugated gate insert strips 23 were evaluated for the purpose ofmaintaining alignment of potatoes during slicing. However, it was found that 7