Posts Tagged “pulp temperature”
It has been nearly three decades since TransFresh Corporation’s Rich Macleod created the Fresh Produce Mixer & Loading Guide and he still receives requests for 100 or more of the guides each year.
The guide continues to be a useful tool in preventing the transporting of incompatible fruits and vegetables, which can result in the loss of product quality, and even lead to claims or rejected loads.
Over the years Macleod believes increased knowledge of what produce items mix well together during transit has contributed to reducing problems with refrigerated produce loads arriving at destination – particularly on longer hauls. As stated on the guide, “Some items may tolerate less than perfect conditions for short periods (less than two days). Produce mix and temperature becomes critical with longer transit times.”
However, despite all of the information available on the topic, problems with arrivals of product at destination due to incompatibility of the produce on board still occurs.
“They (shippers) know if there is a load that is 90 percent head lettuce and there is a pallet of apples in the trailer, that is not good,” Macleod says. But sometimes chances are taken with incompatible items, especially if the transit time is not very long.
“The sensitivity of what does and doesn’t go on a load has really improved in the last five years,” Macleod notes.
He adds there are more larger carriers hauling produce and they are becoming more sophisticated with what to put in the trailer on mixed loads. He laments there seems to be fewer independent owner operator than in the past doing long haul trucking.
Macleod sees more shippers using their own brand on many fruits and vegetables, and they have become more particular how these products are loaded and transported because their name or brand is on the box.
He points out when a produce hauler picks up product in a warmer climate, there usually is a lot of activity, because a lot of produce is being moved. This increases the chance the product may not have been pre-cooled. While Macleod does not see this as a huge problems, he notes it still does happen.
“The primary protection for the driver (and receiver) is they know the pulp temperature of the product going into the trailer,” Macleod says.
Since Macleod works a lot with strawberry shipments, particularly through TransFresh’s Techtrol program, he is seeing less resistance to the driver being provided pulp temperature information on product just being load. He isn’t sure if it is a major problem with other produce commodities.
‘In the packaged vegetable industry they (shippers) clearly don’t want the driver punching a hole in it, but there is a way to do it. But it’s incredibly important to what that (pulp) temperature is going into the trailer,” Macleod stresses. “It impacts how much demand is going to be put on your reefer unit, the quality of the product, and it can impact the chances of rejected loads.”
Even if the driver did not observe the loading, he can still alert the customer (receiver) while still at the dock, if he notices the product is three to four degrees warmer than it should be.
(This is the fourth in a five-part series featuring an interview with Rich Macleod, vice president, pallet division North America for TransFresh Corp., Salinas, CA. He has been with the company since 1976, and has a masters degree in post harvest science from the University of California, Davis.)
When hauling the more perishable produce items such as strawberries, knowing your reefer unit, maintaining proper temperature and taking a pulp temperature at shipping point becomes even more critical. Doing things right results in delivering a better product to your customers, as well as reducing claims and load rejections.
These points are among some important findings in a study released last year, Comparison of Pallet Cover Systems to Maintain Strawberry Fruit Quality During Transport. As the title indicates, the study compares modified air controlled strawberry shipments using carbon dioxide (CO2).
Following up on that report, HaulProduce.com had an extensive interview with Rich Macleod of TransFresh Corp. of Salinas, whose product Tectrol came out looking pretty darn good when compared with competing companies offering controlled atmosphere bags covering palletized loads of strawberries.
The project was a combined effort of the University of California, Davis and the University of Florida in conjunction with the USDA.
“What this (study) demonstrates is when you put a bag over the pallet, you are going to get some in-transit warming,” Macleod observes. “It doesn’t matter whether it is a Tectrol (application) or somebody else’s bag because the warming is about the same for all of them.”
Where Tectrol shined in the study was the quality of the berries upon arrival after the cross country hauls from California to the east coast.
But back to the issue of in-transit warming. Rich points out when a palletized load is entirely bagged, the driver has to account for warming when adjusting the refrigeration unit set points accordingly at a colder temperature than if the load were “naked.”
He says, “I believe you can run a fully bagged Tectrol load (of strawberries) at 30 degrees F. if your (reefer) unit is well calibrated and your unit was built within the past four years.”
However, realistically Macleod knows most drivers prefer a 36-degree F. setting. As they become more familar with these type of loads they find out one can drop the setting to 34 or even 32 degrees.
“They (drivers) should not have issues with warmer product, if it is bagged. And they should not have any issues with frozen product. There are a number of drivers that have been incredibly successful handling Tectrol loads at 32 degrees F., but they know their units inside out and have them calibrated. They know what the floors are and the coldest temperatures that unit will be. Thirty-two degrees is a reasonable compromise.”
Macleod stressed that even if the fruit has been properly pre-cooled, carriers have to realize those bagged pallets will increase the temperature.
In fact the study itself points out in shipments with non covered pallets, the clamshell packaged strawberries remained at 32 to 35 degrees F. However, pallets covered with bags resulted in the temperature increase of three to four degrees by the time it arrived at destination.
“The rise in temperature during shipments indicate the trailers were unable to maintain the recommended 32 degrees F….” the study states.
What can a driver do if the pallets are already covered with CO2 filled bags upon arrival at the dock?
Although it is too late for a visual inspection of what is being loaded by the driver, Macleod says, “a well run (shipping) company should allow the driver to take a pulp temperature and they (shipper) should provide tape to reseal that hole (made by the driver to take the pulp temperature). It is a common practice and shippers respect that.”
(This is Part 2 0f 5, featuring an interview with Rich Macleod, vice president, pallet division North America for TransFresh Corp., Salinas, CA. He has been with company since 1976, and has a masters degree in post harvest science from the University of California, Davis.)