Source: South Africa, Australia, and the United States of America
Availability: March through October
Availability: November through March
Source: United States of America
Availability: Year round
A minimum juice content by volume of 28 or 30% depending on grade; color: lemons picked at the dark-green stage have the longest Postharvest life while those picked fully-yellow must be marketed more rapidly.
Yellow color intensity and uniformity; size; shape; smoothness; firmness; freedom from decay; and freedom from defects including freezing damage, drying, mechanical damage, rind stains, red blotch, shriveling, and discoloration.
12-14’C (54-57’F) depending on cultivar, maturity-ripeness stage at harvest production area, and duration of storage and transport (can be up to 6 months).
Optimum Relative Humidity
Rates of Respiration
Temperature 10’C (50’F) 15’C (59’F) 20’C (68’F)
ml CO2/kg.hr 5-6 7-12 10-14
To calculate heat production multiply ml CO2/kg.hr by 440 to get Btu/ton/day or by 122 to get kcal/metric ton/day
Rates of Ethylene Production
<0.1ul/kg.hr at 20 OC (68 OF)
Responses to Ethylene
If degreeing is desired, lemons can be treated with 1-10 ppm ethylene for 1-3 days at 20 to 25 OC (68-77 OF), but this exposure may accelerate deterioration rate and decay incidence.
Responses to Controlled Atmospheres (CA)
CA of 5-10% O2 and 0-10% CO2 can delay senescence including loss of green color of lemons. Fungistatic CO2 levels (10-15% are not used because they may induce off-flavors due to accumulation of fermentative volatiles, especially if O2 levels are below 5%. Removal of ethylene from lemon storage facilities can reduce rate of senescence and decay incidence.
Chilling injury. Symptoms include pitting, membranous staining, and red blotch. Severity depends upon cultivar, production area, harvest time, maturity-ripeness stage at harvest, and time-temperature of Postharvest handling operations. Moderate to severe chilling injury is usually followed by decay.
Oil spotting (Oleocellosis). Breaking of oil cells due to physical stress on turgid fruits causes release of the oil that damages surrounding tissues. Avoiding harvesting lemons when they are very turgid and careful handling reduce severity of this disorder.
Green mold. Caused by Penicillium digitatum which penetrates the fruit rind through wounds. Symptoms begin as water-soaked area at the fruit surface followed by growth of colorless mycelium, then sporulation (green color).
Blue mold. Caused by Penicillium italicum which can penetrate the uninjured peel and can spread from one lemon to adjacent lemons. Symptoms are similar to green mold except that the spores are blue.
Altenaria rot. Caused by Alternaria citri which enters the lemons through their buttons. Preharvest treatment with gibberellic acid or postharvest treatment with 2,4-D delay senescence of the buttons and subsequent decay by Alternaria.
Careful handling during harvesting and handling to minimize cuts, scratches and bruises.
Treatment with Postharvest fungicides and/or biological agents.
Prompt cooling to the proper temperature range.
Maintaining optimum ranges of temperature and relative humidity and exclusion of ethylene during transport and storage.
Effective sanitation throughout the handling system.
[Sources: Mary Lu Arpaia and Adel A. Kader
Dpt of Botany and Plant Sciences, University of California, Riverside, CA 92521
Dpt of Pomology, University of California, Davis CA 95616; University of California Davis – Postharvest Technology Research and Information Center]
Most lemons are displayed in bulk. They should be of comparable size to avoid over handling by consumers in search of the largest fruit. However, offer consumers a choice by complementing bulk displays with bagged lemons. Displays of different sized lemons in two areas of the department can increase sales volume. Display ribbons of lemons amid green vegetables for eye appeal, suggesting use with salad and cooking vegetables. Lemons also make a nice tie-in with melons.
Lemons can be positioned with citrus, green peppers and apples or next to avocados and tomatoes along with guacamole mixes. Merchandise lemon-related gadgets near the display. Lemon faucets, juicers, peelers and graters can spur sales. Also cross-merchandise lemons with seafood department.
Themes: Cross-merchandising lemons with fish at the seafood counter is natural tie-in. Build a lemon boat for tartar sauce. Cut a lemon in half length-wise. Squeeze the juice and scrape shells clean with a spoon. Next, cut a thin slice off the bottom to prevent tipping, and fill with tartar sauce.
Lemon flavor is complementary to avocados and apples and it retards browning on those products when cut. Mix lemons with cooking vegetables since lemon juice is a taste alternative to salt in vegetable dishes.
Beverages are a strong tie-in for summer and around the holidays. Create a lemonade or tea stand display by including pitchers and bags of sugar.
Offer consumers information on the various uses for lemons. Include tips for serving lemons with fish, salads or using for baking or cooking. Fresh grated lemon peel adds aroma to baked goods, fruit compotes, dessert and savory sauces.
Highlight other lesser-known uses for lemons. For example, the juice can remove odors from hands, pots and pans by rubbing with a cut lemon just before washing. Another tip to pass along to shoppers: Lemons can keep garbage disposals smelling good by periodically running used lemon shells through them.
In addition to providing grams and Daily Values, nutrient content descriptors can inform consumers if a nutrient level is considered high or low.
When using a nutrient content descriptor. Food and Drug Administration labeling laws state that the descriptor should be used as in this example: broccoli, a low-sodium food, or broccoli, low in sodium, etc. The statement low-sodium broccoli implies that the broccoli is different or specially prepared. Do not use that type of misleading statement. Nutrient content descriptors allowed for lemons include: fat-free, saturated fat-free, very low sodium, cholesterol free, low in calories and high in Vitamin C.
Wash lemons before use. Foodservice operators can enhance a fish meal several ways: Fresh lemon and butter make a good basting sauce for barbecued fish steaks. When poaching fish, squeeze fresh lemon juice into the poaching liquid to season; it will help white fish retain its color. Serve tartar sauce in lemon boats.
Vegetables such as potatoes, cauliflower and turnips stay white while cooking when lemon juice is added to the cooking water. Substitute lemon juice for vinegar in all seasonings.