b'Chip And Fry Processing Evaluations AmongAdvanced Breeding Clones In Storage.(2018 crop)by Darrin Haagenson, USDA/ARSTheobjectiveofthisstudywasto Tubers were subsequently stored for Chip Clone Evaluationsidentifyadvancedpublicpotato six months at 50, 48, 45, and 42F.Althoughthe2018fieldtrialwasbreeding lines that maintain quality exposed to severe cold stress prior tochipandfryprocessingafterpro- Sugar profiles and processing quali- harvest, 29 of 39 chip clones evalu-longedstorageatcontrastingstor- tyofthenumberedbreedinglines ated had good chip color followingage temperature.Considerable cost werecomparedagainstnamed six months of storage at 45 and 42Fsavingscouldbeachievedat check varieties throughout storage. (Table1,Figure1).Inthisstudy,reduced temperature storage (<45F) Forchipprocessingclones,chips chip quality was assessed using thethrough decreased shrinkage, lower (thicknessof20slices/inchor combined Hunter color score, Snackincidenceofdiseasepressure,and roughly 0.05 inches/slice) were fried FoodAssociationchipcolorrank-decreasedneedforsproutinhibi- in canola oil (365F) for 90 seconds ing, and glucose forming potentialtion. However, prolonged cold stor- using a pilot scale continuous chip (GFP) following six months of stor-age at temperature below 45F often line.Chip color ratings were deter- age.GFPistheratiooftuberglu-resultsinoffcolorproductforma- minedusingtheSnackFood cose:sucroseconcentrationsandtion resulting from enhanced sugar Association five point scale (1 light, GFPisinverselyrelatedtocoldaccumulation, and cold sweetening 5 dark) and a Hunterlab color score sweeteningresistanceasincreasedremains a challenge to growers and (HunterLabD25withDP-9000 GFPratiosareassociatedwithprocessors.processor) was recorded.decreasedcoldsweeteningresist-ance or poor chip color. Of the chipProcessingcloneswereobtained Chip clones were classified accord- clonestestedin2018;NY152,fromelevenpublicbreedingpro- ingtomethodsofSowokinosand NY157,ND7799c-1,COTX12235-grams including 39 chip clones and Glynn (2000) where: 2W, W12078-76, and MSV030-4 had48russetclones.Fieldtrialswere thelightestchipcolor,whichwasplantedon05/23/2018andgrownClass A: clones provide good qual- similartocommercialchecksunder irrigation at Larimore, North itychipsprocesseddirectlyfrom Lamoka, Dakota Pearl and Waneta.Dakotawithagronomicpractices 42F storage, seven month. Intotal,therewere11clonesinfollowing North Dakota production 2018 that were classified as Class A.guidelines.In2018,plantswereClass B: clones provide good chip TheseClassAcloneshadglucoseexposed to severe cold stress prior to quality from 45F, but not from 42F concentrations<0.10mg/g,at6harvest.Field plots received 10-12 storage,months of storage at 42F with theofsnowtheweekofOctober7, seven month. exceptionofDakotaPearland2018,andairtemperaturesap- ND7799c-1thathad0.134andproached10Fwithdaytimehighs Sowokinos, J. R. and M. Glynn 2000. 0.187 mg/g glucose concentrations,reaching the upper 20s in successive Marketing potential of advanced potato respectively (sugar data not shown).days.Harvestwascompletedon breeding clones.Valley Potato Grower. Although MSV030-4 provided excel-October 18, 2018.Frost damaged or 65(110):6-8. lentchipquality,theGFPofwater soaked potatoes were imme- MSV030-4from45Fstoragewasdiately discarded and healthy tubers For russet clones, fry color of planks significantlyelevated(0.88)com-were stored at 95% RH, 50F for two (5/16x7/8)wereassessedusing pared to other Class A clones (Tableweeks.After initial sampling of sug- photovolt % reflectance immediate- 1).arsandprocessingfrycoloron ly after batch frying for 3.5 minutesNovember6,thetemperaturewas at 375F.Sucrose and glucose con- An additional 18 clones were ratedraised to 57F and tubers were stored centrationsweredeterminedatall as Class B clones or provided accept-for an additional four weeks in an samplingdatesusingaYSI2900D able chip color following 45F stor-efforttoimprovefrycolorby Biochemistry Analyzer. age.Glucoseformingpotentialdecreasingglucoseconcentrations. from Class B clones at 42F storage20 POTATO GROWER SEPTEMBER/OCTOBER 2019'