Courtesy of PVMI Rich Novy US Dept. of Agriculture, Agricultural Research Service, Aberdeen, Idaho USA
58% Created in 1984 for the breeding, development, and release of new potato varieties for the states of Idaho, Oregon, and Washington. 39 varieties released since 1984 Varieties released include: long russet-skinned long and round whites specialty varieties Emphasis on processing varieties suitable for the PNW Provides 78% of U.S. processing potatoes
Percent of Planted Acres 100 80 60 40 20 0 Impact of Tri-State Potato Varieties on PNW Production 83% Ranger Russet 0% Russet Burbank Umatilla Russet Alturas Modoc Premier Russet 1992 1996 2000 2004 2008 2012 Year Yukon Gem Western Russet WA, ID, OR Classic Russet 46% 25% Sage Russet Alpine Russet Huckleberry Gold Teton Russet Palisade Russet Compiled from data provided by the National Agricultural Statistics Service Courtesy of Mark Pavek and Rick Knowles, WSU
Benefit to industry with improved productivity/quality attributes Must be improvement in one or more characteristics relative to industry standard varieties Must not be substantially weaker relative to industry standard varieties in other key characteristics Important Attributes of Processing Varieties: Tuber Sugar Concentrations Specific Gravity (Dry Matter/Starch Content) Tuber Shape and Size Ability to Store Long-Term Improved Sustainable Production Resistance to diseases and pests Reduced Production inputs, e.g. nutrients and water French Fry Sensory Attributes: Flavor, aroma, and texture How do you improve a clonally propagated crop?
Seedling Tuber Production
10-11 years Why 10-11 years? Seed Increase Over Years Replicated Field Evaluations Yield & Disease Sensory & Processing Evaluations Commercial Evaluations, Input, & Interest Development of Management Profiles
A primary consideration in breeding Cold Sweetening in Storage Conversion of tuber starch to sucrose and then to reducing sugars: glucose and fructose Standard processing varieties stored at 7.2 to 10 o C Colder storage temperatures increase reducing sugars and make for dark, unacceptable fry color
20-30%
Reducing Sugars (mg/g dry wt) 80 75 70 65 60 55 50 45 40 35 30 25 20 15 10 5 0 4 3 USDA Color Classes 2 1 R 2 = 0.87*** 19 mg/g DW ~ 0.19% glucose FW 0 0 5 10 15 20 25 30 35 40 45 50 55 60 Photovolt Reflectance Knowles et al., WSU
Long term storage at < 7.2 o C Low reducing sugars maintained Direct from 13 weeks @ 4.4 C with light chip/fry color Maintains tuber quality Reduced Shrinkage Prolongs natural tuber dormancy Reduction in storage diseases Objective of every breeding program having a processing focus PVMI Photo Eight cold-sweetening varieties released by the Tri-State Program since 2000 Premier Russet
Premier Russet T. Brandt and N. Olsen, University of Idaho
Premier Russet Russet Burbank USDA 3 or more color and at least 6.4 mm in length Sugar Ends (non-uniform sugar distribution) T. Brandt and N. Olsen, University of Idaho
Novy et al. 2012. Palisade Russet: A Late Blight Resistant Potato Cultivar Having a Low Incidence of Sugar Ends and High Specific Gravity. American Journal of Potato Research 89:89 101. Dual-Purpose Russet Strengths: Higher Total & US Yields Good Processor Low % of Sugar Ends Late Blight Resistance Resistant in Toluca Valley Additional Resistances Sustainable/Organic Weakness: High Specific Gravity Problem in PNW--good in low gravity regions
Cultivar Palisade Russet Ranger Russet Russet Burbank Fry Color Sugar Ends 0.9b 7b 1.3ab 46a 1.5a 39a Data represent means from five full-season trials conducted at Aberdeen and Kimberly, ID from 2003-2005. Mean values followed by the same letter are not significantly different from one another (P<0.05) based on Tukey s test.
Cultivar Palisade Russet Ranger Russet Russet Burbank Aberdeen, Idaho Hermiston, Oregon Othello, Washington 3.5b 7.6b 5.9b 9.3a 14.0a 11.7a 11.3a 18.4a 9.6ab Evaluations conducted at Pullman, WA using tubers harvested from 2006-2009 trials following 3 months storage at 8.9 o C followed by 4 months at 7.1 o C. A difference of 9 units between bud and stem end constitutes non-uniform fry color. Mean values followed by the same letter are not significantly different from one another (P<0.05) based on Tukey s test.
Background Identified as neurotoxin & carcinogen in rodents Suspected carcinogen in humans 2002: Acrylamide was found in carbohydrate rich foods processed at higher temperatures No country has set limits on Acrylamide Content in Food Concern to Potato Processing Industry Formation High Heat Reducing Sugars Free asparagine Mitigation Production: eg N & asn Chemical: asparaginase Processing: lower oil temp/duration of frying Low sugar/asparagine varieties
Contribution of sugars to acrylamide formation: Amrein et al. 2003. J. Agric. Food Chem. 51:5556-5560 17 potato varieties: R 2 =0.88 combined Williams. 2005. Food Chemistry. 90:875-881 5 potato varieties: R 2 =0.97 for both glucose and fructose, respectively De Wilde et al. 2006. J. Agric. Food Chem. 54:2199-2205 16 potato varieties: R 2 =0.82 combined Matsura-Endo et al. 2006. Biosci. Biotechnol. Biochem 70:1173-1180 5 potato varieties: R 2 =0.70 for both glucose and fructose, respectively Differences among varieties for acrylamide formation primarily explained by concentrations of reducing sugars
Contribution of asparagine to acrylamide formation Amrein et al. 2003. J. Agric. Food Chem. 51:5556-5560 17 potato cultivars: R 2 =0.01 Asparagine + reducing sugars: R 2 =0.91 vs- 0.88 for sugars alone Williams. 2005. Food Chemistry. 90:875-881 5 potato varieties: R 2 =0.1 De Wilde et al. 2006. J. Agric. Food Chem. 54:2199-2205 16 potato varieties: R 2 =0.04 However, some exceptions Matsura-Endo et al. 2006. Biosci. Biotechnol. Biochem 70:1173-1180 5 potato varieties: R 2 =0.03 when reducing sugars are limiting R 2 =0.68 when levels of reducing sugars are >2x levels of asparagine
Shepherd et al. 2010. Food Chemistry. 123:568:573. Genetic segregation for acrylamide production 43 breeding clones A subset of 227 clones from three years of data on chip color 12 best and worse and 19 covering the range between: 4 o C Harvested tubers stored at 4 o C for 4 mos Chip color, sugars, asparagine, and acrylamide data Acrylamide Formation: Reducing sugars: R 2 =0.25 Asparagine: R 2 =0.33
Reducing sugars and asparagine combined Explained 53% of the variation in acrylamide Increases in both sugars and asparagine=increased acrylamide in chips Breeding clone with lowest acrylamide had both low reducing sugars and asparagine Conclusion of authors: In conclusion our data indicate that conventional breeding approaches need to select for both low reducing sugar levels and low asparagine levels, in order to produce new improved processing cultivars that will deliver reduced acrylamide levels in the processed products.
Purpose I.D. of varieties having low acrylamide following processing Rapid evaluation and adoption by industry Coordinated Effort Processors USPB / NPC State Commissions QSR/Retail Potato Breeders Federal Grant First Trial Conducted in 2011: 81 Entries
ME OR ID ND MN WI CO
Acrylamide Three readings taken: After harvest and following 3 months and 7 months Acrylamide storage Concentrations 8.9 o C Among 81 NFPT Entries 2350 Low and high acrylamide entries identified having relatively consistent rankings across all three sites Trend for increasing acrylamide 1310 concentration with increased duration of storage 955 Range of acrylamide observed (averaged across all 3 sites) 355 595 838 113 142 187 Highest Average Early 3 mos 7 mos Lowest Concentration (ppb)
Asparagine Two readings taken: After harvest and following 7 months storage Asparagine at 8.9 o Concentrations C Among 81 NFPT Entries 17,4 More entry variability across sites 13,6 Range of asparagine observed (averaged across all 3 sites): 8,2 7,5 3,3 3,4 Highest Average Early 7 mos Lowest Concentration (mg/g DW)
0,7 0,6 0,59 0,6 0,5 0,4 0,3 0,2 0,1 0 0,44 0,37 0,33 0,37 0,33 0,19 0,14 Idaho North Dakota Washington Early Mid-Storage Late Storage
I.D. of low acrylamide varieties/advanced breeding clones Useful to the processing industry in meeting current CA acrylamide reduction mandates and possible national mandates However, must meet agronomic, processing and QSR specifications Low acrylamide formation industry acceptance Useful to potato breeders Asparagine and acrylamide concentrations relative to industry standards Interplay between asparagine and sugars on acrylamide Reducing sugars a key contributor to acrylamide formation Asparagine become more important with longer-term storage Information allows directed breeding to develop low-acrylamide varieties Substantial improvements can still be made in reducing acrylamide formation in potato products by developing varieties which are resistant to low temperature sweetening and with lower asparagine contents either by breeding or genetic engineering. Vinci, R.M et al. (2012) Acrylamide formation in fried potato products Present and Future, a critical review on mitigation strategies, Food Chemistry 1138-1154.
80% of fresh tuber weight Approximately 70% of tuber dry matter is starch Stark and Love, Potato Production Systems, 2003 Too Low: Greater Oil Uptake Too High: Tougher Fry Texture
Desired Ideal Tuber for Yield Size: of French Fries 170-284 g: ~70% (68-74%) >284 g: ~ 30% (28-40%) WSU Potato Research Group
Important to QSR s Customers expectations met Quality assurance New varieties must meet French fry quality standards Russet Burbank the standard for comparison Fry Characteristics Color Rigidity Texture Flavor Aroma
50 Fries >2.54 cm in length assessed Fry Externals Good: The fry has more than 66% of the following: A surface that is moderately crisp and dry to the touch. An appearance and feel of four edges Poor: The fry has more than 33% of the following: It bends (likes a rubber hose) It collapses and/or sags when picked up Fry Internals Good: The fry has more than 66% of the following: A baked potato appearance with white fluffy crystals when gently squeezed Center is firm, but not hard/undercooked Poor: The fry has more than 33% of the following: Wet, soggy, fishy, and or/oil soaked No baked potato internals Center is very hard
The Bite The shell should separate easily when bitten No noticeable tough pulling sensation, but rather a soft, crisp, clean bite Chewing Attributes When chewing, the shell should feel dry, thin and flaky, with no chewy or leathery characteristics No noticeable buildup in the molars The shell material should seem to dissolve in the mouth
Trained Panel Taste, After-taste, Aroma, and Texture Evaluated 15 point scale 0 = none 1 = barely detectable 2.5 = very slight 5.0 = slight 7.5 = slight to moderate 10.0 = moderate 12.5 = moderate to extreme 15.0 = extreme Comparisons with: Russet Burbank: Approved by prior QA grading New varieties must consistently score comparable or better than Burbank Ultimate decision for acceptance of new variety from QSR customer
Typical Sensory Ratings: Russet Burbank Shoe String Fries Oil Aftertaste Exterior Overall Aroma Off Aftertaste Exterior Caramelized Aroma 10,0 Exterior Oil Aroma Caramelized Aftertaste Sweet Aftertaste Bitter Aftertaste 8,0 6,0 4,0 Exterior Off Aroma Interior Potato Aroma Interior Off Aroma Potato Aftertaste 2,0 Crispness Overall Aftertaste 0,0 Toughness Off Flavor Firmness Oil Flavor Mealiness Sweet Taste Moistness Caramelized Flavor Persistence of Crispness Potato Flavor Overall Flavor Chewiness Oily Mouthfeel
Long-term Storage Short to mid-term storage most varieties Russet Burbank: Up to 10 months following harvest Alpine Russet: Released in 2008 Both dormancy & ability to process from long-term storage Blackspot Bruise 80% bruise-free is ideal 70% is minimum Tolerance for Bruising: 255 g peeled tuber: Area no more than 9.5 mm diameter circle <255 g peeled tuber: Area no more than 4.8 mm diameter circle Two or more bruises of any size = bruised potato
Low Input Varieties: Important in Sustainable Production
Reduced Production Inputs: Nutrients Improved efficiencies in: Physiological Utilization Root Uptake Water Tolerance to water stress Pesticides Pest /Pathogen resistance Benefits? Reduced Production Costs Fertilizer Pesticides Mitigate Water Issues: Leaching of nutrients Urban vs- agricultural demands Address Consumers Concerns Environment Food Safety
Courtesy of Dr. Jeff Miller Late Blight Susceptible: Dead Vines Late Blight Screening Trial Bonners Ferry, Idaho-2004 -No Fungicides -Late Blight Inoculated Defender
Defender Late Blight Resistant Processing Varieties Palisade Russet Stevenson, W. R. et al. 2007. Fungicide spray programs for Defender, a new potato cultivar with resistance to late blight and early blight. Plant Dis. 91:1327-1336. Even if only 20% of Washington and Wisconsin potato growers adopted this new cultivar, savings of several million dollars due to lower fungicide costs and fewer losses in storage could result. Defender additionally presents a viable alternative for organic potato producers. (Stevenson et al. 2007) Reduced and conventional fungicide spray programs in WI & WA and organic (WA) Standards: Russet Burbank & Ranger Russet
Total Yield (cwt/a) 500 450 440 400 350 400 Alturas Russet Burbank 300 250 155 240 0 90 180 270 360 Nitrogen Rate (lb N/A) J. Stark & P. Bain, U. of Idaho
Five Irrigation Environments 1. Full Season Irrigation at 100% ET 2. 100% ET with Early Cut-Off on Aug 10 3. Full Season Irrigation at 70% ET 4. 70% ET with Early Cut-off on Aug 10 5. Step Down 100%-70%-50% Six Varieties Russet Burbank Ranger Russet Russet Norkotah Alturas Summit Russet GemStar Russet Split plot, randomized complete block Five Replications 2 years 2002 and 2003 J. Stark et al., Potato cultivar response to seasonal drought patterns. In Review, American Journal of Potato Research
70 60 58 61 50 40 30 40 39 40 45 30 30 38 43 2002 2003 20 10 0 100% ET 100% ET 8/10 70% ET 70% ET 8/10 Step Down
40 35 30 37.8 30.2 80% 30.9 82% 25 GemStar Alturas 20 Ranger 15 Burbank Norkotah 10 Summit 5 0 100% ET 100% ET 8/10 70% ET 70% ET 8/10 Step Down 29% 32%
Must have the complete package. Acceptable Tuber Sugar Concentrations Specific Gravity Tuber Shape and Size Ability to Store Long-Term French Fry Sensory Attributes: Appearance, flavor, aroma, and texture and then some for the future: Improved Sustainable Production Lower Acrylamide in Fries and Other Potato Products
Tri-State Colleagues: Special Thanks to: Dr. Jonathan Whitworth, USDA-ARS, Aberdeen, ID Dr. Rick Knowles and Dr. Mark Pavek, Washington State University Dr. Nora Olsen, Tina Brandt, and Dr. Jeff Stark, University of Idaho Steve Vernon, Debra Schmidt, and Angel Marie Bowie, J.R. Simplot Company, Caldwell, ID NFPT Researchers and Industry Representatives Project Support Staff Mark Fristad, Darren Hall, Charlene Miller, Brian Schneider, Steve Wheeler