How Much Do Fruits and Vegetables Cost?
USDA's Economic Research Service (ERS) has estimated
average costs for 153 fresh and processed foods, using
data from Nielsen's 2008 Homescan panel to estimate average
retail prices per pound (or, for juices, per pint). Households
participating in Nielsen's Homescan panel keep a record
of their food purchases at retail stores including quantities
bought, amount of money paid, and date of purchase. Purchases
at supermarkets, supercenters, convenience stores, drugstores,
and other types of retail facilities are all included.
Nielsen also provides sample weights for estimating what
all households paid across the contiguous United States.
In order to estimate the cost to consume each food, ERS
researchers further adjusted retail quantities to account
for removing inedible parts and cooking that occur prior
to consumption. Costs to consume foods were then estimated
per edible cup equivalent as defined in the 2010 Dietary Guidelines for Americans.
Selecting Foods to Price
A wide variety of fruits and vegetables is available
at retail stores across the Nation. ERS priced selected
types of fruits and vegetables in various fresh and processed
forms. For example, apples include fresh apples, dried
apples, and applesauce. Apples are also priced in two
juice forms—ready-to-drink and frozen concentrate
that must be reconstituted at home.
Products identified for pricing are very specific products.
The final selection of food products was determined in
part by data constraints—ERS researchers could not
price fresh produce sold on a "random weight" basis, such
as whole, untrimmed heads of Romaine lettuce. Marketers
usually do not prepackage untrimmed heads of Romaine lettuce,
but sell the heads in loose form instead. Consumers can
choose heads from a store display and place their selection
in a plastic bag. Because the weight of the food item
placed in the bag is not fixed, the term "random weight"
describes this way of selling lettuce. Nielsen did not
provide data on sales of individual random weight foods
in 2008.
Even with certain data limitations, ERS was able to price
many types of fruits and vegetables in at least one fresh
form. For example, retailers sell Romaine hearts along
with random-weight heads of Romaine lettuce. The hearts
are generally sold in bags that include a manufacturer's
or retailer's brand name along with a Universal Product
Code (UPC, a type of bar code). Compared with an untrimmed
head of Romaine lettuce, Romaine hearts require less washing/preparation
and may also be more expensive.
Processed foods are priced by ERS in a similar manner
as their fresh counterparts. Researchers identified processed
foods that are as closely comparable in nutritional quality
as possible to the same type of fruit or vegetable in
fresh form. For that reason, ERS researchers excluded
apple juice blended with other juices and banana chips
made with oil. Some sweetened and flavored foods were
included because excluding all sweetened or flavored foods
would have overly restricted the selection. For example,
ERS priced canned peaches packed in juice and in various
types of syrup.
Estimating the Price of Buying Selected Foods at Retail
The next step in ERS's price analysis was to estimate the average cost of foods at retail stores on a per-pound (or per-pint for juices) basis. To do so, the 2008 Homescan data was used to estimate total expenditures by U.S. households on each food item and the total quantities bought. Next, average retail costs were calculated as the ratio of total expenditures to total quantities. From the Nielsen data, it was estimated that households living in the contiguous United States spent $247.1 million on frozen concentrated orange juice, which could make 480.7 million pints. Thus, the average retail cost of frozen concentrated juice was estimated at 51 cents per pint ($247.1 million/480.7 million pints).
To estimate total expenditures and quantities, ERS aggregated total purchases made by all households, in all seasons of the year, in all package sizes, and at all retail store formats. Nielsen's sample weights were applied to make the estimates representative of what all households across the contiguous United States paid in 2008.
Calculating aggregate quantities of foods purchased by households was more complicated than calculating aggregate household expenditures on each type of food. Fruits and vegetables are sold primarily by the pound or ounce. However, some items are priced on a "count basis," such as cantaloupes for $2.50 per melon. To convert these sales to a weight basis, ERS used the USDA National Nutrient Database for Standard Reference, Release 21 (SR). The SR estimates the weight of a medium cantaloupe at about 1,082 grams (roughly 2.4 pounds), including the weight of the rind and inedible cavity contents such as seeds.
Estimating the Costs to Consume Fruits and Vegetables
The final step in the analysis was to estimate the costs
for consuming fruits and vegetables per edible cup equivalent
as defined in the MyPyramid Equivalents Database,
Version 2.0 (MPED). The MPED measures only the edible
portion of a food item once it has been cooked or otherwise
prepared for consumption. One pound of store-bought fresh
pineapple yields 0.51 pounds of edible pineapple after
the removal of the core, crown, and parings. For many
fruits and vegetables, a 1-cup equivalent is equal to
the weight of a full measuring cup of edible food. For
example, a cup equivalent of cooked whole kernel corn
weighs 164 grams whether from fresh, frozen, or canned
product. On the other hand, it takes 2 edible cups of
a raw, leafy vegetable, like spinach, to make a 1-cup
equivalent, but only one-half cup of edible dried fruit
to make the same.
Data on cooking yields, edible shares, and inedible shares
(when available) of fruits and vegetables are from USDA's
Standard Reference (SR) and Food Yields Summarized
by Different Stages of Preparation (Handbook 102).
If weight is lost in preparation, ERS defines a food's
retail-equivalent weight as:
Retail-equivalent weight = weight of a cup equivalent/(1 - share lost)
where shares are expressed as fractions. For example,
the SR reports that 10 percent of a fresh apple is inedible,
while the MPED lists the weight of a 1-cup equivalent
of raw apple with skin at 106 grams. To eat a 1-cup equivalent,
households must therefore buy 106/0.9 = 117.78 grams of
whole fresh apples. In contrast, if weight is gained in
preparation, a food item's retail-equivalent weight is
defined as:
Retail-equivalent weight = weight of a cup equivalent/(1 + share gained)
where shares are again expressed as fractions. USDA Handbook 102 reports that cooking dry beans increases their weight. The weight of the cooked product is approximately 240 percent of the weight of the dry beans prior to cooking. The MPED further lists the weight of a 1-cup equivalent of cooked pinto beans at 173 grams. Households must therefore buy 173/2.4 = 72.08 grams of dry pinto beans at a retail store to eat a 1-cup equivalent at home.
Because cup equivalent weights are in grams, it was necessary
to convert earlier estimates of retail prices from a dollars-per-pound
basis to a dollars-per-gram basis (by dividing by 453.59),
and calculate the cost to eat a cup equivalent of a food
item as:
Price per cup equivalent = (average retail price per gram)
x (retail-equivalent weight in grams).
For more information, see How Much Do Fruits and Vegetables Cost?
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