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Trial Number 0

Client Number 318

Project Number 1

Trial Purpose:

To evaluate supplied product against a traditional automatic dishwashing liquid.

Date Run:

04/15/2009

Experiment Procedure:

This test method covers a procedure for measuring performance of a mechanical dishwashing detergent in terms of the buildup of spots and film on glassware. It is designed to evaluate household automatic dishwasher detergents during this cleaning procedure. Glass tumblers are washed in a mechanical dishwasher in the presence of food soil and the levels of spotting and filming allowed by the detergents under test are compared visually.

This test method is intended as a laboratory screening test to determine performance of the detergent under actual use conditions, but will not necessarily predict performance under all end-use conditions.

Tableware used was as follows: 10-in. diameter Dinner plates, 7-in. diameter Salad plates, 6-in. diameter Cereal bowls, and stainless steel Cutlery. Six dinner plates, six knives, six forks, and six spoons were used. These pieces were all placed on the lower rack of the dishwasher. Eight glass tumblers were loaded on the top rack.

Standard Food Soil Components: nonfat powdered milk, margarine, and wheat-based cooked cereal (optional).
Standard Food Soil Preparation: A mixture of 80 weight % of margarine and 20 weight % of powdered milk was prepared. The margarine was warmed until fluid and the powdered milk was mixed thoroughly.

A total of 40 g of food soil was distributed onto the six dinner plates, using a hand held swab. The VWR International Under-counter Glassware Washer (model 82020-922) was loaded as follows: In the lower (plate) rack, distribute the six soiled dinner plates uniformly with the smaller plates and bowls placed alternately about the dinner plates until the rack is fully loaded. In the upper (glass) rack, distribute the glass tumblers evenly. The eight glasses were placed along each side, four to a side.

Maintain a water temperature of 130 6 5°F (54.4 6 3.8°C) in the dishwasher.
Detergent Concentration—Use the quantity of detergent specified by the manufacturer. For a thorough investigation, evaluate at over and under usage.

Rating: The tumblers were visually inspected after each cycle for film and spotting. Evaluations were based on the following scale.

Rating Spotting Filming
1 no spots none
2 spots at random barely perceptible
3 about 1/4 of surface covered slight
4 about 1/2 of surface covered moderate
5 virtually completely covered heavy

Obtain number ratings by averaging the ratings for individual tumblers, keeping spotting and filming results separate.

Cascade Pure Rinse formula was used as the traditional dishwashing liquid. One set of trials was conducted using the supplied cleaner without rinse aid and a second set was conducted using the supplied rinse aid. No rinse aid was used with the Cascade formulation.

Trial Results:

The Cascade product had the best spotting and film rating. The supplied product cleaned better with the rinse aid. The film rating was about the same as it was without the rinse aid. Both trials with the supplied product resulted in ratings that averaged under the second level of the charts - spots at random and barely perceptible filming.

    Trial 1   Trial 2   Trial 3  
Product  Glass Spotting Film Spotting Film Spotting Film
Cascade A 1 1 2 1 1 1
  B 1 1 2 1 2 1
  C 2 1 2 1 1 1
  D 1 1 1 1 3 2
  E 1 1 2 1 1 1
  F 1 2 1 1 2 2
  G 1 1 1 1 1 2
  H 1 1 2 1 1 1
Overall Average Spotting Filming          
  1.42 1.13          
               
Alpha A 2 1 1 1 1 1
  B 2 2 2 1 2 1
  C 2 1 2 1 2 2
  D 2 1 2 1 2 1
  E 3 2 2 1 2 2
  F 2 1 2 1 1 1
  G 2 1 2 1 2 1
  H 1 1 2 1 1 1
Overall Average Spotting Filming          
  1.88 1.17          
Alpha A 2 2 1 1 1 1
w/rinse B 2 2 2 1 1 1
aid C 2 1 1 1 2 1
  D 2 1 2 1 1 1
  E 2 1 2 1 2 1
  F 2 1 1 1 2 1
  G 1 2 1 2 1 1
  H 2 1 1 2 2 1
Overall Average Spotting Filming          
  1.58 1.21          

Success Rating:

Results successful using TACT (time, agitation, concentration, and temperature, as well as rinsing and drying) and/or other cleaning chemistries examined.

Conclusion:

Based on comparing the supplied product and rinse aid against the traditional automatic dishwashing product, the product performed slightly lower for both spotting and filming. However, overall cleaning when compared to the rating system resulted in effective cleaning. A second cleaning protocol will be conducted using gravimetric analysis on similar substrates and soils.

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