FRESH PRODUCE TOOLKIT
Storing Fresh Produce
Dr. Cindy Tong, Extension Postharvest Horticulturalist
Karen Lanthier, Asst. Director, Sustainable Agriculture and Food Systems, Regional Sustainable Development Partnerships
Greg Schweser, Assoc. Director, Sustainable Agriculture and Food Systems, Regional Sustainable Development Partnerships
Ryan Pesch, Extension Educator, Community Economics, Center for Community Vitality, U of M Extension
Matt Olson, Fresh Purchasing Manager, Mississippi Market
Quality Fruits and vegetables benefit from certain storage conditions. If possible, try to make a
space that fits each of these optimal temperature ranges and features1:
•
Three separate rooms set at three
different temperature ranges for optimal
storage of fruits and vegetables (32 - 36°
F, 45 – 50° F, and 55 – 60° F)
•
If only two rooms are available, set one
at 35 - 40° F and another at 50 - 55° F.
•
If only one room is available, use a
compromise temperature of 40° F and
produce that normally prefers 55 – 60° F
can be stored in an air conditioned or
cool area until able to be displayed.
•
Move cold-tolerant produce items (32 36° F) to cold storage as soon as possible
(Photo Credit: Matt Olson)
because delays will shorten shelf-life. Avoid
moving produce repeatedly between warm and cold places because these changes could
result in water condensation in packaging, encouraging pathogen growth and decay.
•
Optimal relative humidity for most produce in storage rooms is 85- 95%.
•
Good air circulation is a must to maintain temperature and humidity balances - make
space between boxes, pallets, and walls.
For example storage room layouts, see p. 9 and Appendix F of the Retail Fruit and Vegetable
Marketing Guide2:
http://www.cdph.ca.gov/programs/cpns/Pages/retailfruitandvegmarketingguide.aspx
Handling Fresh Produce
Temperature Control
Fruits and vegetables that are tolerant of 32 - 36°
F or 45 – 50° F temperatures should be kept in
refrigerated display cases. A few items (like
apples, pears, kiwifruit, and oranges) that do not
lose water quickly and have long shelf lives, can
tolerate short-term (1-2 weeks) storage at room
temperature. Ideally, storage case temperatures
should match optimal storage temperatures. If
you have an older refrigeration case, determine if
and where colder or warmer spots exist and
adjust to place vegetables and fruits as close to
their ideal temperatures as possible. For example,
place “cold-loving” asparagus toward the back of
an old case if the case has a cold air outlet there,
and put “cool-loving” bell peppers toward the
front of the display case where the temperature
may be closer to their ideal 45 – 50° F.
Make sure the produce is cooled to its
recommended temperature when you first place it
(Photo Credit: U of M Extension RSDP, 2016)
in the display case since many cases do not have
enough capacity to cool products from a warm temperature to their ideal temperature. Make sure
cold air is able to circulate within the case.
Misting
Certain fruits and vegetables benefit from high humidity conditions. Listed below are fruits and
vegetables that benefit from misting and a few additional tips to optimize produce shelf life:
•
Some common produce items that benefit from misting – if exposed to airflow and not
packaged - include:
o
•
Beets, broccoli, Brussel sprouts, cabbage, carrots, cauliflower, celery, corn (sweet),
green onions (scallions), kale, leeks, lettuce, parsley, radishes, spinach, and sprouts.
Excess air movement can cause water loss in fresh produce, so protect produce with
perforated films when the store is closed and occasionally mist during store hours using a
plastic spray bottle filled with potable clean water.
• Place asparagus vertically with cut ends on a water absorbent pad or shallow container of
potable water.
Crisping
Leafy greens that have wilted and are
less than a week old may be revived by
crisping. To crisp greens, trim the
bottom of the stalk, soak the entire
head in cool (not cold) potable water for
at least 20 minutes, and then put the
head in the cooler. The cool (or “tepid”)
water will be taken up by the head
through the newly cut end, and the
cooler’s low temperature will help
complete water reabsorption.
Greens that could benefit from crisping (Photo Credit: Ryan Pesch)
Benefits to Cleanliness
Minimizing in-store produce exposure to chemical or pathogen contamination is good practice, so
be sure to regularly clean display tables, cases, cabinets, or other features in contact with fresh
produce. It is also good practice to have a rotating cleaning schedule. For example, the produce
areas can be divided into sections for cleaning. Depending on size, one or two sections can be
deep-cleaned each week, rotating through each section on a regular schedule.
Ethylene Sensitivity
Controlling the rate of ripening is critical when selling fresh produce. Certain fruits and
vegetables naturally produce a gas called ethylene which can increase the rate of ripening of
some produce. Ethylene gas is used purposefully in some commercial operations to ripen
harvested produce like tomatoes and bananas, but it can be a nuisance in other situations.
Separating high ethylene producers from low ethylene producers can increase shelf life of
produce items susceptible to ethylene. Ensuring adequate air circulation within coolers can also
help decrease ethylene levels within the coolers. Another option is the use of ethylene absorbing
products. Note that ethylene production is temperature-sensitive. The colder your cooler, the less
likely that produce will synthesize and emit ethylene or react to the ethylene. Conversely, the
higher the temperature of your storage area, the more likely ethylene emitters will produce the
gas and sensitive items will react to ethylene.
•
High Ethylene Producers: Apples, bananas (when ripe), cucumber (when overripe), green
onions, grapes, honeydew, mangoes, potatoes, stone fruits (plums, peaches, pears,
apricots), tomatoes
o NOTE: Gasoline powered machines or tools (e.g. with internal combustion engines)
also produce ethylene, so be cautious in storing produce near these areas.
•
Low Ethylene Producers:3 Asparagus, berries, broccoli family (including Brussel sprouts,
cabbage, cauliflower), carrots, cherries, green beans, eggplant, lettuce, onions, parsnips,
peas, peppers, sweet potatoes squash, watermelon
High Ethylene Producers
Low Ethylene Producers
Storage/Handling Tips for Locally Grown Fresh Produce
Inspect locally-grown produce carefully at delivery to make sure that you have received the quality
you and the farmer have agreed upon. Trim and store the produce as you would non-local
produce.
Certain produce (e.g. lettuce, cauliflower, radish, and salad mixes) that you receive from your local
farmers may benefit from being handled more gently than individually-wrapped or bagged
equivalents from your distributor. Without a plastic covering, the produce may be more prone to
water loss and bruising. Therefore, locally-grown produce may benefit from practices like crisping,
misting, and gentle handling.
RESOURCES CITED
1.
2.
3.
Kader, A and Thompson, J. Grocery Store Display Storage. University of California, Davis. Perishables
Handling Quarterly. August 2001, Issue 107.
Retail Fruit and Vegetable Marketing Guide. California Department of Public Health. Accessed 0ct. 21, 2016.
http://www.cdph.ca.gov/programs/cpns/Pages/retailfruitandvegmarketingguide.aspx
Roper, T., Delahaut, K., and Ingham, B. Storing fruits and vegetables from the home garden. University of
Wisconsin Extension. 2006. Retrieved from http://learningstore.uwex.edu/assets/pdfs/A3823.pdf
QUESTIONS OR COMMENTS?
Send a message to Assistant Program Director for Sustainable Agriculture and Food Systems,
Karen Lanthier, at [email protected].
Project funding provided by a Minnesota Department of Agriculture
Specialty Crop Block Grant
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