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Standards for the Growing, Harvesting, Packing, and Holding of
Produce for Human Consumption (the Produce Safety Rule).
Subpart L of the Produce Safety Rule addresses equipment
and tools " that are intended to, or likely to, contact covered
produce; and those instruments or controls used to measure,
regulate, or record conditions to control or prevent the
growth of microorganisms of public health significance.
Examples include knives, implements, mechanical harvesters,
waxing machinery, cooling equipment (including hydrocoolers),
grading belts, sizing equipment, palletizing equipment,
and equipment used to store or convey harvested covered
produce (such as containers, bins, food-packing material,
dump tanks, flumes, and vehicles or other equipment used
for transport that are intended to, or likely to, contact covered
produce). " Requirements address equipment and tool design,
construction, workmanship, installation, maintenance, storage,
and inspections as well as cleaning and sanitation. On a
global level, the 2003 Code of Hygienic Practice for Fresh Fruits
and Vegetables, the Codex Alimentarius (36) incorporates
routine cleaning and sanitizing of food-contact surfaces into
their recommendations for the primary production of fresh
produce. Within the industry, commodity groups have
developed commodity-specific food safety guidelines in
which best practices address cleaning and sanitizing of
equipment used in the field.
Since the 1990s, as evidenced by the aforementioned
food safety guidelines and standards, equipment has been
recognized as a potential conduit for pathogen transmission
from the environment to fresh produce. However, equipment
had often received less scrutiny than other means of microbial
cross-contamination in the field until recent circumstances
brought renewed attention to field equipment clean-ing
and sanitation practices. During a foodborne illness
outbreak attributed to Listeria monocytogenes contamination
of prepackaged salads, swab samples taken from equipment
surfaces and internal framework used to harvest lettuce
contained in the mixes tested positive for this pathogen.
Genetic analysis of L. monocytogenes isolates from equipment
samples revealed a match with the outbreak strain isolated
from patients affected by this outbreak (30).
As noted above, various types of tools, equipment, and
containers have direct contact with crops during produce
harvesting operations (44, 110, 158). Many produce commodities
(e.g., fruit, vegetables, and nuts) are harvested with
hand-held tools and placed by hand into containers or onto
mechanized harvest-aide equipment surfaces or conveyer
belts (45, 135, 161, 188). However, use of mechanical and/
or automated harvesting equipment is becoming increasingly
necessary and attractive, driven primarily by challenges in
labor availability that have affected the industry's ability to
harvest product in a timely fashion or to its full productivity
per acre. In addition to equipment and tools used to separate
product from the remaining plant and roots, harvesting operations
may also involve crop contact with auxiliary accumulation
and transport equipment and implements such as bins
and cartons (87, 103, 125, 146, 157), cloths used to wipe
harvested product (151), and workers' hands or gloves
(19, 52). For numerous produce commodities such as head
lettuce, berries, and cantaloupe, it is a common practice to
pack harvested product into retail-ready packaging (e.g.,
plastic clamshells, bags, or cartons) in the field. Berries are
placed directly into consumer units (clamshells) of various
sizes by individual workers. Field-packed cantaloupes are
generally placed on a conveyor, distributed on a large mobile
packing platform for size grading, and placed in single-use
corrugated fiber cartons or reusable packaging containers.
For diverse leafy greens, harvested product is typically
placed on individual packing station platforms or a common
conveyor and may be further trimmed by machine or handheld
tools and sprayed with water containing a minimal
amount of an antimicrobial and antibrowning agent before
being packaged or packed for transport. Equipment used
in these activities includes various types of food-contact
surfaces (e.g., blades, bands, conveyors, tabletops, and
cutting boards) constructed with a variety of materials such
as plastics, silicone, rubber, textiles, or metal. Many of these
food-contact surfaces have components that are difficult to
clean, due to either their design and construction (e.g., niches
or places that are hidden or unreachable) or the wearing or
corrosion of materials (e.g., formation of grooves or cavities)
(57).
For some commodities and/or growing regions, preharvest,
harvest, and postharvest operations are fully integrated
within a company, whereas for other commodities or growing
regions these activities are segregated among several
contractors. During harvest season, harvesting equipment
use is highly dynamic; equipment is frequently moved between
fields within a ranch, among crop owners (as defined
by business contracts), and even among growing regions as
production shifts with seasonal changes. Because of these
supply chain and business structure complexities, cleaning
and sanitizing activities can often be a daily or even splituse
day logistical challenge. Beyond decisions regarding
when to clean, decisions about cleaning methods, cleaning
location and frequency, and even next-day preoperational
recleaning also present significant challenges to equipment
operators. This review includes a discussion of current
industry practices, the food safety hazards related to equipment
and tools used during produce harvesting and field
packaging or packing activities, and the subsequent food
safety risk to harvested produce within and between lots
and farms when harvesting equipment and tools become
contaminated. The objective of this review was to compile
and summarize relevant research and synthesize relevant
findings to broaden awareness of and enhance the use of
best practices for produce harvesting equipment cleaning
and sanitation.
March/April Food Protection Trends 127
Food Protection Trends - March/April 2023

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