1. Dishwashing and Waste Disposal
Chapter 16
Dishwashing and Waste Disposal
(c) 2014 by John Wiley & Sons, Inc.

2. Introduction to Dishwashing
Dishwashing is the process by which dishes, glasses, flatware, and so on are cleaned by using a combination of three things:
Hot water – Sufficient amounts of water, at hot enough temperatures to sanitize. Water amounts, temperatures and lengths of wash and rinse cycles specified by NSF International.
Detergent – Sufficient wetting action to soften water, penetrate food particles and loosen them from dish surfaces.
Motion – Necessary to cover all dish surfaces, with sufficient water volume and velocity to wash and rinse items fully.
(c) 2014 by John Wiley & Sons, Inc.

3. In this chapter, you will learn to:
Learning Objectives
In this chapter, you will learn to:
Describe sizes, types, and ratings of dishwashers, and how to evaluate their features.
Explain the purpose and functions of booster heaters.
Explain the steps for safely cleaning glassware, plateware, and flatware.
Identify the functions of food disposals and waste pulpers.
Identify the functions and features of specialty washers.
(c) 2014 by John Wiley & Sons, Inc.

4. Analyze warewashing functions for speed and potential cost-savings
Choosing a Dishwashing System
Analyze warewashing functions for speed and potential cost-savings
Overall dish volume – What and how much will you be washing?
Individual job functions – How and how often are dishes handled before reaching the dish machine? How much heavy lifting is required?
Working conditions – Can you improve on the noise, exposure to heat, humidity, and chemicals in a typical dish room?
Peak hours – A speedy, well organized dish room means you’ll need to stock less inventory of plates, glasses, etc.
Role of guests – Will they clear their own tables? Use a conveyor belt to send cafeteria trays to the kitchen?
Equipment service records – Sure signs the system needs a closer look: Continued dish machine maintenance problems, breakage, overall inefficiency.
(c) 2014 by John Wiley & Sons, Inc.

5. Getting ‘em clean while controlling costs…
Choosing a Dishwashing System 5
Getting ‘em clean while controlling costs…
Maximize use of sanitation personnel in kitchen.
Detergent is expensive! Control its use by prescraping or prewashing.
Use enough water, and enough energy to heat it, without wasting either.
Run only fully loaded dish racks through the washer.
Use proper wetting agent, which promotes faster rinsing, drying and prevents spotting.
Laying out dish room efficiently helps reduce breakage.
(c) 2014 by John Wiley & Sons, Inc.

6. A Dish Room Layout
Design the system with productive workflow, safety, and sanitation in mind
© John Wiley & Sons, Inc.
(c) 2014 by John Wiley & Sons, Inc.

7. These temperature differences are key
High-Temp or Low-Temp?
These temperature differences are key
The low-temp dishwasher washes and rinses at 140ºF, using chemicals instead of super-hot water for sufficient sanitizing.
Separate chlorine dispenser for sanitizing function is installed nearby (on wall or undercounter).
The high-temp dishwasher washes at 140º F, rinses at 180º F. Must be installed under a ventilation hood. Rinse water is heated that extra 40º by a booster heater, built in or separate unit.
Many dish machines are field convertible. They can be changed from high-temp to low-temp (or vice versa) with manufacturer’s instructions.
(c) 2014 by John Wiley & Sons, Inc.

8. A few dish machine comparisons…
High-Temp or Low-Temp?
A few dish machine comparisons…
HIGH TEMP
LOW TEMP
Requires more space: Under ventilation hood, possible separate booster heater
Reduced ventilation requirements; no need to install under hood
Better for items that react to chemicals (made of pewter, aluminum, silver)
Chemicals save money on energy for heating water
Faster drying time
Works well for glassware, coffee mugs
Works well for dissolving proteins, food residue
(c) 2014 by John Wiley & Sons, Inc.

9. Cost, environmental concerns drive detergent selection
Detergent Use
Cost, environmental concerns drive detergent selection
Phosphate-free dish detergents are better for the environment – but some are convinced they don’t work as well.
High phosphate levels in lakes, streams cause excessive algae growth. Some states don’t allow them in detergents.
Check labels for eco-friendly attributes: Are ingredients toxic? Biodegradable? Fragrance-free? Is packaging minimal and recyclable?
Do not exceed manufacturers’ recommendations for detergent amounts, sanitizing chemicals per load.
Too much leaves residue
Too little doesn’t clean well enough
(c) 2014 by John Wiley & Sons, Inc.

10. Do you really need a dish machine?
Dishwasher Sizes and Ratings
Do you really need a dish machine?
Dish volume – Decide whether you’ll have enough dirty dishes to require mechanical dishwashing. It can always be done by hand.
Available space – Is there room to store dirty dishes and wash them periodically, all at once? Larger machines are run less frequently than smaller ones – but what fits in your dish room?
(c) 2014 by John Wiley & Sons, Inc.

11. Undercounter Types of Dishwashers
A small but highly efficient unit that fits on or under a countertop.
Can also fit beneath a dish table with sink for prerinsing.
Some are freestanding.
Uses 3 to 5 gallons of water per wash cycle; each cycle is less than 2:30 in length.
Low-temp or high-temp models available; runs on electricity.
Courtesy of Champion Industries, Huntington, West Virginia.
(c) 2014 by John Wiley & Sons, Inc.

12. Glasswasher Types of Dishwashers
Courtesy of Champion Industries, Huntington, West Virginia.
A variation of the undercounter dish machine. Washes with tap water; final rinse with sanitized water.
Quick-drying option heats water to 212ºF.
Cycle takes about 20 minutes; uses 3 gallons of water.
Conveyor models can clean up to 1000 glasses per hour.
(c) 2014 by John Wiley & Sons, Inc.

13. Single-Tank Door Style or Stationary Rack
Types of Dishwashers
Single-Tank Door Style or Stationary Rack
Most widely used model. Efficient and easy to operate.
Washes 35 to 80 dish racks per hour.
Freestanding; often installed with dish tables on either side.
Uses 1.2 gallons of water per wash cycle.
Must be positioned under an exhaust canopy.
Courtesy of Champion Industries, Huntington, West Virginia.
(c) 2014 by John Wiley & Sons, Inc.

14. Moving Dishwashers Types of Dishwashers
Rack conveyors – Single tank ( racks per hour) and double-tank ( racks per hour)
Water may be heated by electricity, gas or steam
People can load/unload; optional automatic features can help minimize labor costs
© John Wiley & Sons, Inc.
(c) 2014 by John Wiley & Sons, Inc.

15. Side loader – Saves space in corner installations.
More Options for Conveyor Machines
Side loader – Saves space in corner installations.
Curved unloader – Pushes clean racks off conveyor.
Condenser – Dries moist air exhausted from dish machine. In some cases, may replace need for exhaust hood. Increases height requirements.
Blower-dryer – Electric or steam-heated blower dries dishes faster, but increases length and height of unit and adds exhaust requirements.
Cowls – Add ventilation capability at each end of dish machine, but also add length.
(c) 2014 by John Wiley & Sons, Inc.

16. Circular Dishwashers Types of Dishwashers
Courtesy of Champion Industries, Huntington, West Virginia.
Exterior portion of conveyor is curved, minimizing need for employees at both ends of the machine.
Three “types” based on rack capacity per hour: Type 1 (180 racks); Type 2 (387 racks); Type 3 (480 racks).
Requires use of curved dish tables in some spots.
Depending on size, has 1, 2 or 3 water tanks.
(c) 2014 by John Wiley & Sons, Inc.

17. Flight-Type Conveyor Dishwashers
Types of Dishwashers
Flight-Type Conveyor Dishwashers
Also called rackless conveyors or belt conveyors.
A large, long dish machine for use in settings of 600 to 800 meals per hour.
Moving conveyor has plastic-tipped pegs to hold dishes. Special racks for glassware, flatware fit onto pegs.
Manufacturers offer a variety of water- and energy-saving options.
© John Wiley & Sons, Inc.
(c) 2014 by John Wiley & Sons, Inc.

18. Booster Heaters
Most dish machines today have built-in booster heaters.
Separate unit can be standalone or installed undercounter.
This small water tank raises final rinse cycle water temperature to 180ºF for sanitizing.
Energy use depends on amount and temperature of incoming water supply.
Gas and electric models available – select yours depending on local utility costs. Newest models use infrared heating.
Steam-heated boosters are found in large facilities where steam is created for other reasons.
Even the largest booster heater will pay for itself within a few years through utility cost savings.
(c) 2014 by John Wiley & Sons, Inc.

19. Dishwasher Maintenance
Don’t program shorter cycles or use less detergent or sanitizing chemicals to try to save money.
Leave dish machines door open when not in use. On machines with curtains, clean and hang them up to dry at end of day.
Dish machines have same mineral buildup problems as other equipment that uses water. Remove mineral scales regularly.
Remove and inspect spray nozzles to clear clogs.
Clear scrap screens daily.
Inspect water lines, water pump shafts for leaks.
Check water temperatures, water pressure.
(c) 2014 by John Wiley & Sons, Inc.

20. Care and Cleaning of Dishes
Keeping glassware breakage to a minimum:
Don’t use glasses still hot from being washed.
Place dirty glasses directly into dish racks; don’t stack them elsewhere.
Use flatware baskets in bus tubs; don’t stack flatware in glasses.
Don’t scoop ice out of an ice bin with a glass. Use the scoop!
Instruct servers not to pick up multiple glasses at a time in one hand.
Protecting plateware:
Store plates level with or below the plating area. When workers have to reach up, more dishes get dropped.
Don’t use one dish to scrape food off another.
Pre-rinsing dishes in very hot water can cause stains, discoloration.
Teach servers not to overload trays, bus tubs.
Air-dry plates when possible.
Don’t stack plates more than 12" high; cover if stored for more than a week.
(c) 2014 by John Wiley & Sons, Inc.

21. Care and Cleaning of Dishes
Keeping flatware looking good:
Presoak (no more than 30 minutes) before sending into dish machine.
Makes it easier to remove food particles in wash cycle.
Minimizes contact with acidic foods that can corrode.
Don’t use steel wool or scouring pads on flatware.
Pack loosely into flatware baskets.
Consider a flatware washer, which cleans and sanitizes in 90 seconds.
Keep flatware out of garbage disposal and trash cans.
Wetting agent in rinse cycle will help minimize spotting; in hard-water areas, a water softener may also be needed.
Consider use of a cutlery polisher or, for silver plate, a burnisher to maintain shiny finish and remove spots.
(c) 2014 by John Wiley & Sons, Inc.

22. The Pre-Rinse Station Waste Disposal Options A pot sink
A (low-flow) spray nozzle or faucet with flexible hose
A food waste disposer – if your city allows it
Continuous feed shreds waste whenever it is turned on
Batch feed handles a specific amount at a time
Sized by horsepower or number of meals served
Rotor size is as important as horsepower
Automatic reversal function is handy in case of jams
Read the instructions to prevent serious (and preventable) accidents
Scrap basket and/or vinyl guard is important for sink drain; prevents bones, jewelry, flatware from ending up in disposer
(c) 2014 by John Wiley & Sons, Inc.

23. Waste Pulpers and Collectors
Waste Disposal Options
Waste Pulpers and Collectors
Waste pulper is preferred alternative to food disposer when building is on septic tank instead of sewer system
Also used in addition to disposers in busy kitchens
Paper, Styrofoam, plastic, aluminum foil – it shreds them all.
Uses much less water than disposals
Chops solid waste into a slurry, then squeezes out the water to reduce waste to 15% of its original size
Can be composted if incoming waste was completely biodegradable
Deodorant, sanitizers can be added to reduce odor
Downsides: Machines are expensive, noisy; pulping reduces size of waste but not its weight. Some items (glass, cloth, etc.) can’t be pulped.
Scrap collector is a perforated pot that sits in sink, straining scraps as water circulates through it. Uses only 2 gallons of water per hour.
(c) 2014 by John Wiley & Sons, Inc.

24. Can save up to 75% on labor costs and 50% on detergent and water.
Washing Pots and Pans
Mechanical pot/pan washer – similar to dish machine but adapted for large pots and pans, sheet pans, etc.
Can save up to 75% on labor costs and 50% on detergent and water.
Takes 4 to 15 minutes per cycle
Undercounter models available to save space
Requires scrapping area for pre-rinsing and scraping, and sufficient landing space
Power sink – Three-compartment sink with built-in water heater, water circulation, and high-pressure spray capability
Water jets or whirlpool-style circulation options
Some units can retrofit onto regular pot sink
Requires presoak, rinsing area and sanitizing sink
(c) 2014 by John Wiley & Sons, Inc.