United States Department of Protecting Agriculture Agricultural Perishable Foods Marketing Service During Transport by Truck Transportation and Marketing Programs Handbook Number 669 September 1995 Reprinted July 2008 B Protecting Perishable Foods During Transport by Truck by B. Hunt Ashby Agricultural Marketing Service Transportation and Marketing Programs September 1995 Reprinted July 2008 The U.S. Department of Agriculture (USDA) prohibits discrimi- nation in all its programs and activities on the basis of race, color, national origin, age, disability, and where applicable, sex, marital status, familial status, parental status, religion, sexual orientation, genetic information, political beliefs, reprisal, or because all or part of an individual’s income is derived from any public assistance program. (Not all prohibited bases apply to all programs.) Persons with disabilities who require alternative means for communication of program information (Braille, large print, audiotape, etc.) should contact USDA’s TARGET Center at (202) 720–2600 (voice and TDD). To file a complaint of discrimination, write to USDA, Director, Office of Civil Rights, 1400 Independence Avenue, S.W., Wash- ington, D.C. 20250–9410, or call (800) 795–3272 (voice) or (202) 720–6382 (TDD). USDA is an equal opportunity provider and employer. i Contents Introduction I. Important Factors in Protection of Perishable Foods Refrigeration ....................................................................................................................1 Refrigeration Methods ....................................................................................................2 Mechanical Refrigeration ..........................................................................................2 Ice ..............................................................................................................................3 Cryogenic Refrigerants ..............................................................................................3 Trailer Design and Construction......................................................................................4 Insulation ....................................................................................................................4 Air Circulation Systems ............................................................................................4 Multi-temperature Vehicles ........................................................................................6 Humidity ..........................................................................................................................7 Precooling the Product ....................................................................................................8 Freezing and Chilling Injury............................................................................................9 Controlled and Modified Atmospheres..........................................................................11 II. Preparation for Loading Adequacy of Equipment ................................................................................................13 Cleaning and Sanitation ................................................................................................13 Vehicle Maintenance......................................................................................................13 Precooling or Prewarming of the Vehicle......................................................................16 Preloading Checklist......................................................................................................16 III. Loading Considerations Type of Air Delivery......................................................................................................17 Type of Shipping Container ..........................................................................................17 Whether Frozen or Nonfrozen ......................................................................................18 Bracing Needs................................................................................................................18 Compatibility of Mixed Loads ......................................................................................18 Whether Palletized or Unitized......................................................................................19 Length of Transit Period................................................................................................19 IV. Loading and Load Patterns Basic Terminology ........................................................................................................20 Loading Vehicles with Top-air Delivery........................................................................20 Hand-stacked Loads ................................................................................................20 Unit Loads ................................................................................................................22 Loading Vehicles with Bottom-air Delivery..................................................................22 Unit or Pallet Loads ......................................................................................................24 Vented Loads..................................................................................................................24 Top-iced Loads ..............................................................................................................24 Loading Checklist..........................................................................................................27 V. Individual Commodity Requirements Fresh Fruits and Vegetables ..........................................................................................28 Apples ......................................................................................................................28 Apricots ....................................................................................................................29 iii Artichokes ................................................................................................................29 Asparagus ................................................................................................................29 Avocados ..................................................................................................................30 Bananas ....................................................................................................................30 Beans (green, snap, or pole) ....................................................................................31 Beans (lima, in pods)................................................................................................31 Beets ........................................................................................................................31 Beet Tops ..................................................................................................................32 Blackberries..............................................................................................................32 Blueberries................................................................................................................32 Broccoli ....................................................................................................................33 Brussels Sprouts ......................................................................................................34 Cabbage ....................................................................................................................34 Cantaloupes ..............................................................................................................35 Carrots ......................................................................................................................35 Cauliflower ..............................................................................................................35 Celery........................................................................................................................36 Cherries ....................................................................................................................36 Corn (sweet) ............................................................................................................37 Cranberries................................................................................................................38 Cucumbers................................................................................................................38 Eggplants ..................................................................................................................39 Endive and Escarole ................................................................................................39 Garlic (dry) ..............................................................................................................39 Grapefruit..................................................................................................................40 Grapes ......................................................................................................................40 Kale ..........................................................................................................................41 Kiwi Fruit ................................................................................................................41 Lemons ....................................................................................................................42