Presentation to the National 

Organic Standards Board 

Celery Panel

Andrew Milkowski

April 24, 2019
Outline

• Response to questions of the National Organic 

Standards Board regarding celery as a curing 

ingredient in processed meats

• Discussion of human nitrogen oxide physiology 
1. Is nonorganic celery powder still essential for 

the production of processed meats?

• I am unaware of any organic products containing high enough 

concentrations of nitrate or nitrite that would make them 

candidates to be a curing ingredient.

– The minimal Nitrite concentration needed to cure processed meat 

for pathogen safety and color benefits is 80-200 ppm (based on 

weight of meat used) 
Nitrite – The Multi-functional Food Additive

• Development of cured meat color

• Cured meat flavor

• Functions as an antioxidant

• Antimicrobial – C. botulinum, C. perfringens, L. monocytogenes

Nitrite** Nitric oxide (NO)

Myoglobin Nitrosomyoglobin Nitrosohemochrome

Nitrate*

*Pure nitrate or celery powder

**Pure nitrite or cultured celery powder 
4. Are there strategies to produce organic celery 

powder that is standardized to consistently meet 

safety and other requirements of the meat 

processing industry? 

• I am unaware of any, however this is not an area where I have 

expertise.
6. Are there commercially available agriculturally 

produced alternatives to celery powder? What is 

your experience with them? Are they organic? 

Does their use vary by application? Are they more 

effective in one application compared to another? 

• There are vegetables and tubers (e.g. celeriac, Chinese cabbage, 

endive, fennel, kohlrabi, leek, parsley, celery, cress, chervil, 

lettuce, red beetroot, spinach) which have enough nitrate in them 

to be candidates, but they have flavors and colors which limit 

their use on a practical basis.
7. What is the latest information on the human 

health risks of nitrate and nitrites present in 

processed meats from either synthetic or plantbased sources?

• IARC classifications of Nitrite & Nitrate (2006) and Processed 

Meats (2015)

• Important to note: 

– “IARC Monographs Programme evaluates cancer hazards but not the risks 

associated with exposure.” (https://monographs.iarc.fr/, Q&A link)

– The 2015 working group noted that cured meats are a minor source of nitrate/nitrite 

in human physiology

– There is no difference related to the source in how nitrate and nitrite are metabolized. 

As simple ions, naturally derived and synthetic nitrate and nitrite are physiologically 

identical.
Nitrogen Oxide Physiology

Hord, N. G., Y. Tang, et al. (2009). "Food sources of nitrates and nitrites: the physiologic context for potential health benefits." Am 

J Clin Nutr 90(1): 1-10.
Sources of Nitrate, Nitrite and Nitric Oxide Exposure*

Source Nitrate, NO3

- Nitrite, NO2- Nitric Oxide, NO

Diet, ex cured meats 50 - 220 0 - 0.7 -

75g/d cured meats 1.5 - 6 0.05 - 0.6 -

Water 0 – 132 0 - 10 -

Saliva >30 - 1000 5.2 - 8.6 -

Endogenous 

Synthesis

- - 70

* mg/day/adult person

Source: Milkowski, A.L., (2017) Sources of Exposure to Nitrogen Oxides, in Nitrite and Nitrate in Human 

Health and Disease, 2nd edition, Edited by: N.S. Bryan, and J Loscalzo, ISBN: 978-3-319-46187-8, doi 

10.1007/978-3-319-46189-2 Humana Press, New York, pp. 69-82
Nitrate is Secreted in Saliva

• Salivary glands extract nitrate from the blood plasma (25% of the nitrate you ingest from food 

or produce endogenously comes back into saliva)

• Salivary nitrate is chemically reduced by bacteria on the tongue to nitrite (20% of 

the nitrate in saliva)

– Thus 5% of ingested and synthesized nitrate is recycled into ingested nitrite

• Acidified salivary nitrite is protective against periodontal disease pathogens 

• Salivary nitrite is swallowed and enters the acidic stomach

• Acidified gastric nitrite is bactericidal for a number of gastrointestinal 

pathogens and is thus a form of innate immunity
Time Permitting:

Salivary Nitrate and Nitrite

Let’s check Nitrate and Nitrite in our own saliva
Salivary Nitrate and Nitrite

1. Wet the tip of your finger 

with saliva

2. Transfer saliva to each 

pad on the test strip and 

get it thoroughly 

moistened

3. Wait a couple of minutes

4. Hold the test strip with 

the pads up

5. Compare to the scale on 

the screen
Celery Powder

Industry perspectives on re-listing & constraints
An essential ingredient

– Celery Powder remains an essential curing 

agent for organic cured meats

– Only option currently available to comply with 

FSIS food safety requirements

– Cured meat products represent nearly 25% of 

Organic Meat Company’s gross revenue 

annually
Numerous Constraints

• Varietal differences

• Fertility/regional variation

• Nitrate to Nitrite conversion performance

• Sensory panel approval

– Taste

– Color

– Shelf-life
Market dynamics

Why isn’t the market just innovating and 

developing the product?

- Financial risk to the farmers

- Financial risk to the processors 

- Product is used in small amounts

- Potential gain for processors and farmers is 

limited
Environmental impacts

• Is use of synthetic nitrogen increased in 

conventional celery production for powder?

• Largely speculative

– Contracted growers (conventional) have been 

very unwilling to share in-field practices of their 

production systems.
Celery Powder – NOSB Panel

Dr. Erin Silva

University of Wisconsin-Madison

Organic Production Specialist

Question #2

• Compared with growing celery for vegetable 

production, is increased use of synthetic 

nitrogen fertilizers required to produce source 

plants with enough nitrate for celery power 

production?
Answer

• It is Dr. Sindelar’s understanding that there are 

specific recommendations for the production of 

celery for juicing as a meat curing agent, but we 

were not able to ascertain these 

recommendations
Question #3

• Since 2015, what progress has been made on 

the production of organic celery for powder 

production?
Current Grant Funding 

• USDA Organic Research and Extension Initiative 

Planning Grant

 Applied March 2016, awarded June 2016

 Led by the University of Wisconsin-Madison

• Organic Valley’s Farmers Advocating for 

Organics Fund
Experimental Approach

• Variety selection

• Fertility management strategies

• Farm environment

• Harvest date

• Yellow and white beets as alternative plant 

source
Experimental Approach

• Core experiment conducted at certified organic 

land at the UW West Madison Agricultural 

Experiment Station

 Certified organic 10+ years

 Under a vegetable rotation with extensive cover 

cropping

 3.5% organic matter, silt loam soil

 Fertilized annually with pelletized poultry manure 

(aiming for 120 lbs/N per acre, estimating 50% 

availability in given year)
Experimental Approach

• Three replications, split plot design

 Whole plot factor: variety 

 Split plot factor: fertility treatment (foliar feed 

versus sidedressing)

• Planted as 8 week old transplants in June

• Drip irrigated as needed

• Harvested in late September
Experimental Approach

• Samples were juiced and frozen at UW Madison 

 Aimed for within 24 hours of receiving samples, 

which were kept refrigerated

• Samples sent to Kerry Ingredients for further 

testing
Nitrate Concentrations of Organic Celery 

Samples by Variety 

Nitrate (ppm)

2016

Nitrate (ppm)

2017

Calypso 1618 882

Conquistador 1869 811

Tall Utah 2197 1009

Tango 1322 442

Mission 1112

Safir 424

P-value 0.2701 0.0004
Effect of Time to Juicing on Nitrate Concentrations
Effect of Early (145 days) and Late (171 days) Harvests on 

Nitrate Concentrations of Celery
Impact of Supplemental Fertility on Nitrate 

Levels in Organic Celery

2016 Foliar Feeds Unfertilized

Nitrate (ppm) 1549 1743

2017 Sidedressed No Sidedress

Nitrate (ppm) 827 726
Nitrate Concentrations of Organic Celery 

Samples Across Farms

Nitrate

(ppm)

Nitrate

(ppm)

Notes

Wisconsin West Madison ARS 1731 795

Equinox 190

Park Ridge Organics 997 410 CPM; Conquistador

Scotch Hill Farm 221

Blue Moon 450 CPM; Tango

Tipi Produce 207 CPM before and as 

sidedress; Tango

Squashington 102 Cover crop; Tango

California 488 741

P-value <0.0001 0.05
Question #6

• Are there commercially available agriculturally 

produced alternatives to celery powder? What 

is our experience with them? Are they organic? 

Does their use vary by application? Are they 

more effective in one application compared to 

another?
Nitrate Concentrations of Organic Beet Samples 

by Variety 

Nitrate (ppm) Brix Nitrate (ppm) 

standardized to 

Brix

Avalanche 946 2.39 1718

Boulder 561 2.31 1007

Touchstone 719 3.00 1150

P-value 0.2701 ns 0.1175
Continued Work

• Seeking USDA Organic Research and Extension 

funding for larger project
Key Take-Aways

• Significant work has been completed since 

2015 to better understand the ranges of nitrate 

we can anticipate from organically-grown 

celery

• More work needs to be completed to 

understand the role of G x E x M on nitrate 

concentrations and related variability

Classified as General Business

© Kerry 2019

Growing the Market for 

Sustainable, Profitable 

Organic Vegetables

April 24, 2019
2 | Taste & Nutrition | © Kerry 2019

Classified as General Business

The Celery Circle

The number of steps within the celery circle add complexity to this initiative.
Classified as General Business

© Kerry 2019

Are there strategies to produce organic celery powder 

that is standardized to consistently meet the safety and 

other requirements of the meat processing industry?
4 | Taste & Nutrition | © Kerry 2019

Classified as General Business

Sustainable, Profitable Celery Circle: Opportunities & Challenges

Meets Nitrate Spec

Doesn’t Meet Nitrate Spec

Outlet 

Needed

Juicer Distance?

Celery shelf life?

Juicer capacity?

Full Conversion

Progress has been made but additional research is needed to develop a robust process to minimize risk 

for Organic growers.

Cultivar?

Growing Practices?

Acreage Available?

Meets Nitrate Spec
Classified as General Business

© Kerry 2019

Since 2015, what progress has been 

made on the production of organic 

celery for powder production?

Is an increased amount of synthetic nitrogen 

fertilizer required to produce plants with high 

nitrate levels for celery powder production?
6 | Taste & Nutrition | © Kerry 2019

Classified as General Business

Nitrate Levels of Conventional Celery Approaching Maturation

0

0.5

1

1.5

2

2.5

3

0

500

1,000

1,500

2,000

2,500

3,000

3,500

4,000

4,500

5,000

75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97

Cumulative Rainfall (inches)

Nitrate (ppm)

Days post-planting

Nitrate (ppm) Cumulative Rainfall (in)

Foliar Feed 

Applied

0.94 in 

from Day 75

1.38 in 

from Day 81

Maturation

High nitrate levels can be achieved by strategically timing harvest.

Foliar feeding with urea had minimal impact on conventional celery nitrate levels.
Classified as General Business

© Kerry 2019

Since 2015, what progress has been 

made on the production of organic 

celery for powder production?

Since 2015, what progress has been 

made on the production of organic celery 

for powder production?
8 | Taste & Nutrition | © Kerry 2019

Classified as General Business

• Four Organic celery varieties were grown at the West Madison Agricultural Research Station in 2016 & 2017.

• Before planting each year, the soil was tested and a nitrogen based fertilizer was applied so that the starting 

nutrients would have been the same year on year.

Nitrate-to-Nitrite Conversion Data

Organic Celery Variety % Conversion

2016

% Conversion

2017

Conquistador 100% 47%

Tall Utah 100% 27%

Calypso 100% 55%

Tango 85% 49%

Table 1. % Nitrate-to-Nitrite Conversion of Organic celery varieties grown in 2016 & 2017

Organic celery has shown inconsistent performance. Future research is needed to address this.
Classified as General Business

© Kerry 2019

Since 2015, what progress has been 

made on the production of organic 

celery for powder production?

Are there commercially available, agriculturally produced 

alternatives to celery powder? 
10 | Taste & Nutrition | © Kerry 2019

Classified as General Business

Alternate Vegetable Sources Tested

Low Nitrate Levels Conversion Consistency 

Issues

Acceptable Nitrate + 

Conversion

Organic Celery

Spinach Spinach

Conventional Kale

Yellow Beet

Swiss Chard*

Lettuce Chinese Cabbage**

*Dark color may have impact in lighter meat applications.

**Strong flavor impact 

Celery is the ideal vegetable for meat due to its high functional and low organoleptic properties.
Classified as General Business

© Kerry 2019

If not enough organic celery is being 

produced to support the meat 

industry, why not?
12 | Taste & Nutrition | © Kerry 2019

Classified as General Business

Sustainable, Profitable Celery Circle: Opportunities & Challenges

Meets Nitrate Spec

Doesn’t Meet Nitrate Spec

Alternate 

Market 

Needed?

Juicer Distance?

Celery shelf life?

Juicer capacity?

Full Conversion

Progress has been made but additional research is needed to develop a robust process to minimize risk 

for Organic growers.

Cultivar?

Growing Practices?

Acreage Available?

Meets Nitrate Spec
Classified as General Business

Thank you!!!