Issue link: https://read.dmtmag.com/i/491350
STiR tea & coffee industry international 61 Bulk delivery is becoming more common since a plastic lined container holds 21 tons of coffee versus 18 tons when bagged, a payload increase of almost 17%. This represents freight savings of 15% per container (based on coffee traveling from Brazil to New York). The bins make less efficient use of storage space however as ordinary pallets of cof- fee can be stacked six high under OSHA rules. The warehouse floor space required for 500 bags (76,000 pounds) on conventional pallets would accommodate only 24 super sacks holding 48,000 lbs. since the sacks cannot be stacked. Some warehouses regulate temperature and relative humidity, all control exposure to light and odor. Services include customs and FDA food safety clearance at some locations, and weighing and bulk processing at most. Some warehouses also clean, destone, color-sort, size, recondition and even blend coffee. Reference samples are cupped and graded. According to the Coffee Exporters Guide (3rd Edition) coffee must be stored in an easily identifiable manner, using a numbered bay system in the warehouse with the bay numbers and boundaries painted on the floor. Scannable barcodes have replaced painted lot numbers to automate tracking. Every pallet is checked periodically and individual sacks must be readily identified. "Coffee must always be stored on dry, clean wooden baulks or pallets, off the floor away from walls," according to the Guide's list of best practices. "Make weekly stock checks, preferably using people who do not know what is expected and therefore can only report what they find. All stacks should bear a clearly visible stack card, showing the detail and history of the coffee stored. There should never be unidentified coffee in any warehouse. Make regular random weight checks to verify that bags are of the correct weight and that scales have not been tampered with. The guidelines suggest warehouse operators occasionally tear down a stack, again at random, to verify there are no holes or an empty drum in the middle." Stacked and coded, the coffee lies quietly in the dark as it waits the final leg on its journey. The coffee is quiet, but water never rests. Thermodynamic energy in water is known as its activity, which is represented by the symbol: aw. Water activity describes the escaping tendency of vapor. It is measured as the ratio of the vapor pressure within the coffee bean to the vapor pressure of pure water at the same temperature. Moist coffee (10.8% water) is ideally in equilibrium but the effects of dissolved sugars, the capillary effect of vapor, variations in heat, surface tension and interaction with un-dissolved compounds make that unlikely. As it dries water molecules carry away tightly bonded aromatic compounds and when it escapes, water causes mischief throughout the warehouse. Too much humidity leads to a myriad of problems, including growth of deadly toxins known to survive the intense heat of roasting. The ideal relative humidity for storing coffee is 60%, according to research by the Mesoamerican Development In- stitute MDI (www.mesoamerican.org). MDI is a pioneer in environmentally beneficial methods of processing coffee, including high efficiency industrial solar dryers for dry- ing coffee beans and the subsequent storage in the (patented) ultra-hermetic enclosures called Cocoons™ and SuperGrainbags™ manufactured by GrainPro, Inc., Concord, Mass. Dried properly, coffee retains the ideal moisture for nine months to a year when stored in air tight sacks made of non-natural material. According to MDI: "Coffee stored under hermetic conditions will not gain or lose moisture content even during long-term storage in tropical regions (country of origin). This is critical in maintaining quality and flavor, and in preventing mold and associated Ochratoxin that can pose a health risk to consumers." "In jute or natural fibers, the ideal stable moisture is between 10.8%-11.5%. This is the range where water activity is stable. If stored at 60% Relative Humidity (RH) and between 65-75 degrees Fahrenheit the coffee should remain stable for months with little loss of quality," explains Scott Presnell, marketing director at Paris Brothers, Inc. which operates a 650,000 sq. ft. warehouse in Kansas City, Mo. Paris Brothers stores specialty coffee underground in a carefully controlled environment certified to meet the USDA's National Organic Program standard. Gulf Winds stores several million pounds of coffee in 7 warehouses in Houston, LaPorte and Seabrook Tex. Continental Terminals was the primary warehouse for Maxwell House in N.J. and Nestle Beverage Co. in Virginia. Jamaican Blue coffee is still shipped in kegs stored on the Paris Brothers warehouse floor in Kansas City, Mo.