Leopold Center for Sustainable Agriculture

Post-Harvest Handling Decision Tool

General Considerations

Branding - Equipment Considerations - Equipment Links - Food Safety Considerations - Packing Facility Considerations

 

labelsBranding

Putting your farm's logo on your products can increase market recognition, increase brand awareness, and create new marketing opportunities. Labels, twist ties, and hang tags all have the potential to increase sales of your product. Branding also provides a way to let customers know what's special about what they've bought: is it local, organic, or sustainable? Is it grown on a family farm? Branding can communicate these attributes in a retail environment where other differentiation may be lacking.

equipmentEquipment Considerations

Much of the work that distinguishes market farming happens by hand instead of by machine, and this is even truer of the work at the post-harvest handling stage. The speed at which a farmer can accomplish tractor work can be directly correlated to the size of the tractor and the equipment mounted on it. Mechanical harvesting systems often increase the speed of harvest by orders of magnitude; post-harvest equipment, particularly for the smaller, diverse market farms that are the focus of this document, may increase speed by a factor of only two or four.

With manual labor such as that required to move bunched greens into and out of a crisping tank, skill and motivation can make a much bigger difference than a properly-configured setup. In addition, the up-front investment of time and energy that goes into setup and cleanup can make a huge difference in the overall efficiency of an operation handling a diverse range of products.

The combination of diversity of operations, modest efficiency gains, and the manual nature of the work makes investments in new equipment and facilities significantly less concrete than simple number crunching.

The Post-Harvest Handling Decision Web

The following considerations form more of a decision-making web than they do a simple decision-making tree; an investment decision need not pass each consideration to be a good decision for your operation.

Strict (Mostly) Financial Considerations

Reduced Handling - Increasing the speed of post-harvest handling operations can actually reduce the amount of time workers spend moving product around the packing shed.

If operations happen quickly enough, produce can be washed as soon as it comes out of the field, instead of moving into and out of a cooler. This may require some redistribution of labor, with a distinction between the harvest and packing crews; or, it may be more advantageous with some crops than it is with others. At a larger scale of operations, such as that at Gardens of Eagan, the ability to move crops directly from the harvest vehicle into the packing process avoids an entire step of stacking and un-stacking totes of produce, increasing handling speed and reducing wear and tear on the farmworkers’ and farmers’ bodies.

In addition, rapid handling of product can increase the effective batch size handled at one time without increasing the time product sits outside of the cooler, resulting in much less effort in the movement of products. A standard handcart can handle five bushel boxes, while a pallet and pallet jack can move thirty bushel boxes with only a marginal increase in effort.

Product Improvement - In addition to improving the speed at which product is handled, post-harvest handling equipment has the potential to increase product quality. Rapid removal of field heat can significantly improve the shelf life of a product, increasing value to retailers, restaurants, and institutions, as well as final consumers. This increased value can translate into increased sales as well as an increased price.

“Back of the Envelope” Return on Investment Analysis -A Return on Investment analysis, or ROI, provides an answer to the question, “How long will it take to make a profit from this investment?” For large investments, this analysis can be very complete and thorough; for smaller investments, a back-of-the-envelope analysis can provide the information you need to decide whether to move forward. The main question we want to answer is, “Is this investment going to help my farm be more profitable within an acceptable period of time?”

The basic formula for an ROI is the change in Annual Net Income as a result of the investment, divided by the Total Investment. The Total Investment divided by the Annual Net Income gives a more practical figure, the number of years it will take for the investment to provide a return.

Facilities Considerations

Before investing in post-harvest handling equipment, determine if your facilities have or can be modified to have the additional elements required to support the equipment. Changes in water needs, electrical requirements, drainage, and space should be considered.

Weak Link?

Before investing in post-harvest handling equipment, you should first ask if another area of your farm operation should be addressed first.

It doesn’t make sense to scale up your handling capacity if you can’t consistently produce a crop, or don’t have the ability to get it out of the field, or have no place to sell it, or can’t store it until it’s time to sell it.

Sometimes, a weak link can occur because of a large point load, especially for storage crops. At Hog's Back Farm, David van Eeckhout washes all of his storage carrots as soon as they are harvested; with five thousand pounds of carrots to wash in just a few days, a barrel washer will ease the workload considerably. On the other hand, if Hog's Back was washing two hundred pounds of carrots each week for ten weeks, a barrel washer wouldn’t show the same benefits.

Business Structure

The structure of a farm business may point towards or away from the desirability of investing in post-harvest handling equipment. At Spring Hill Community Farm, Mike Racette and Patty Wright have kept their post-harvest equipment at a minimum because CSA members participate in the harvest, washing, and packing process. In this situation, simple systems with few moving parts make the most sense.

Similarly, a farm that relies on high school laborers to complete much of the washing and packing may find that several small crisping tanks make more sense than one larger tank. With several small tanks, one tank can drain and be refilled while others are in use; one large tank can create large pockets of downtime that a motivated and knowledgeable worker could fill with important tasks, but that a minimally-supervised crew of high school kids might not use wisely.

Certain pieces of equipment can help to create systems that workers plug in to, with widgets to crank and a machine to dictate the pace. They can also require a lower input of skills, speed, and personal motivation to do the job quickly and well. Bell peppers in a tank can be removed quickly or slowly, and may get scrubbed or may just get swished around, whereas peppers run through a brush washer move at a certain pace, reducing the human factor in how fast or how well the work gets done.

Is This Driving Me Nuts?

Most people get into farming, or stay in farming, for quality of life reasons. If your current systems leave your hands cold, break your back, or take away from the time you should be reading bedtime stories to your children, that alone can be an adequate reason to consider investing in post-harvest handling equipment.

The Ripple Effect

Occasionally, an investment will have far-reaching effects. For a farm that washes all of their fall roots at one time, speeding up the washing and packing process may provide an additional opportunity to finish fall field work. If that field work includes tasks such planting a final cover crop of rye that builds the soil and controls weeds, the effects of the additional time available at a critical moment may be hard to quantify, but it is meaningful nonetheless.

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barrel washerEquipment Links

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food safetyFood Safety Considerations

The market farmer occupies a rarified niche in the world of food handling, because she takes a raw product (vegetables) through its final step without heating, freezing, or otherwise transforming it before it gets consumed by the customer, often in its raw state.

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packing Packing Facility Considerations

A packing facility for fresh produce ideally provides a comfortable, safe, and efficient environment for people and produce alike. Facilities can range from a bare minimum to something that resembles a licensed processing facility.

Minimum Requirements

It doesn’t take much to get started with a packing facility, but some basic considerations should be taken into account:

A Roof -Some sort of roof, and preferably side walls in addition, should be used to provide protection from sun, wind, and rain. Small farmers often start with a simple farmers market awning. At the author’s Rock Spring Farm, a twenty-foot wide hoophouse with high rollup sides was used for this purpose; in the summer months, shade cloth provided protection from the sun’s heat. Although less-than-ideal, this setup enabled packing in relative comfort for four seasons every year.

A Walk-In Cooler - Every farm visited for this study had a walk-in cooler. Although many ways exist to chill produce, keeping it cool presents another challenge altogether. A walk-in cooler provides the ability to pre-harvest crops, and deliver them chilled to the customer.

Water - At a minimum, the packing facility needs access to a supply of clean, safe water, and a way to move it away from the workers’ boots. A deep gravel bed can provide an inexpensive way to drain water away, as can drainage hoses from the drain plugs of tanks.

Bathrooms and Handwashing Facilities - While none of the farms visited for this study had a bathroom attached to the packing house, everybody had a bathroom available for use by employees and workers. Hand sanitation in the bathroom and in the packing shed is a must; the absence of a handwashing sink creates an additional burden on management to guarantee the cleanliness of hands that come in contact with the produce.

A simple handwashing area can be created with a small, instant electric water heater, a basin, and a soap dispenser for under $500; while warm water isn’t necessary to soap’s effectiveness, it does increase the likelihood that workers will scrub their hands for the recommended twenty seconds.

Other Food Safety Considerations - Allowance should be made for sanitizing equipment and facilities, and pests should be excluded. Open-air packing facilities can’t exclude pests, but can make the packing area less inviting to rodents, flies, and birds by keeping the area clean of debris, installing bird netting over open rafters, and moving pallets regularly.

Food Safety

While food safety issues are beyond the scope of this document, they are important. With every new health scare, the likelihood that all farmers producing food for humans will be required to meet certain standards for facilities and procedures. Any vegetable farmer intending to stay in business should understand the steps they may need to take in a regulated environment, and make investments that will achieve those steps.

Water - Water may well prove to be the most troublesome element in improving packing operations. Most post-harvest handling equipment uses water to clean and cool the produce, so you need a plentiful, easily-accessible supply of clean, safe water. Brush washers and barrel washers rely on a consistent supply of water; although manufacturers can provide more concrete information, a large brush washer can use up to 1.5 gallons of water per minute.

For crisping tanks, and tank-type barrel washers, the rate at which the tank fills can be a severely limiting factor. With inadequate water supplies, slow tank-filling requires a degree of organization and regimentation that can be difficult to achieve. At a rate of ten gallons per minute, a 300-gallon tank will take half an hour to fill, so cycling a full tank of dirty water to a full tank of clean water can easily involve forty-five minutes of downtime. (Not to mention that at low flow-rates, filling a tank with a hose can make it impossible to have a washing machine operating in the house concurrently!)

Washing vegetables uses a lot of water, and it has to go somewhere. The three-season packing houses visited in this study all vegetable wash water out to a pasture or grassy waterway. For a four-season packing facility, deep burial to avoid freezing would be an important consideration.

Adequate drainage from the packing area has an importance equal to or greater than an adequate supply of water coming in. The change from washing in a tank to using a barrel washer, for example, changes the ability of the ambient water to remove dirt and mud from the washing area; draining a tank creates a large flow of water all at once, sluicing the mud away with it; at 1.5 gallons of water per minute, a barrel washer allows mud to build up directly underneath it; in addition, without a catch pan, water from a barrel or brush washer can’t be directed to particular location, increasing the importance of adequate drainage and slope.

Materials Handling

In many ways, farming is a materials handling game. The more stuff you move the more quickly (while maintaining product quality) the more profitable your farm is likely to be.

Concrete may well be the foremost way to improve the materials handling aspect of the packing shed. Pallet jacks operate most efficiently on concrete, and it can greatly increase the ease of operation for two-wheeled dollies.

Access points should be designed according to product flow, and made flexible enough to accommodate new knowledge and new developments. Even for farms operating on a very small scale, all access points should be designed for the potential use of a pallet jack, with room to steer in and out.

Access for harvest and delivery transport should also be considered. For harvest vehicles, drive-through capability can greatly increase the efficiency with which product can make the transition from field to packing shed.

Coolers for Produce Storage - You can’t build a big enough cooler, so packing shed design should accommodate future potential needs for cooler expansion. Coolers should be big enough for palletized product, with enough room to maneuver and organize product as well as to store it.

Additional Storage - Waxed produce boxes, although designed for contact with moisture, are not designed for continual, long-term contact with water. They must be stored in a dry area. Rodents also have an excessive fondness for these expensive items.

Plastic clamshells can deform slightly in extremely cold weather, causing them to close with difficulty or not at all. Accommodation should be made for temperature-controlled storage for these items.

Electricity

Most post-harvest handling equipment utilizes some sort of electrical motor. Electrical outlets should provide adequate access without stringing electrical cords over long distances or through water. Outlets should be protected with a Ground-Fault Interrupter (GFI, or GFCI) switch, and be outfitted with a wet location in use cover to keep water from contacting outlets that have equipment plugged in.

Most equipment runs on a 110-volt supply, although refrigeration and ice machines may require a 220-volt supply.

Seasonal Considerations

In the Upper Midwest, the three-season packing facility seems to be the most prevalent design. All of the facilities visited for this project were open to the elements, and none had made arrangements for permanent heat in their packing facilities. Two had the potential to be sealed up and a unit heater utilized to provide temporary heat.

Growers looking into season extension – either with hoophouses or storage crops – should consider for how many dates each week and for how long into the winter they plan to wash and pack their produce when designing a packing shed.

Water management in an Upper Midwest winter can provide a real challenge, since extreme temperatures can freeze even moving water. At Rock Spring Farm, the author installed perforated drainage tile pipe five feet below the ground to move water from the packing shed to the drainage area, providing an opportunity for water to gradually soak into the groundwater on its way to a possibly frozen outlet.

System Capacity

As a farmer himself, the author is aware that farmers tend to run themselves and their facilities at overcapacity much of the time. Most market farmers can’t afford to invest in excess capacity that creates additional overhead, but at the same time, we can’t ask our employees to do what we, as entrepreneurs, are willing to do to achieve financial and lifestyle success. Designing a facility that is large enough, but not too large, and comfortable enough, but not too comfortable, is a task very dependent on the experience of the individual grower.

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