Food Evaluation, Food Resource [http://food.oregonstate.edu/], Oregon State University, Corvallis, OR

PHYSICAL AND CHEMICAL METHODS OF EVALUATION FOODS

E-MAIL
From: Deborah Yacas
Sent: Thursday, May 27, 2004 2:32 PM
To: food@orst.edu
Subject: Outdated Information on Food Resource web site
ERIC LARSEN FROM SUNKIST GROWERS CONTACTED ME AND INFORMED ME THIS INFORMATION IF VERY DATED AND THE EQUIPMENT ADVERTISED IS NO LONGER AVAILABLE.

This instrument is no longer available. You might "jury rig" one of your own. Get cups or glasses of known heights and use them as standard. Decide how long you are going to let it sit when you turn it out/over and how you are going to measure the sag. The Ridgelimeter would give you an automatic % sag, related to gel strength. You will need to take your original minus the final sag height all divided by the original height. The more sag the weaker the gel.

Sunkist Growers

Price: $90. 00
Ontario, California 91764

Directions:

Measurement of gel rigidity (Limits of sag: 10 to 340/o)

1. Material to be tested must completely fill a Ridgelimeter glass. A collar of masking tape will permit an over fill and gel can be leveled with wire slicer before measuring.

2. Material must be removed from Ridgelimeter glass without being damaged. For a gelatin gel the gel can be removed by dipping the glass into warm water until the gel loosens from the glass. For pectin, starch and egg gels, the gels can be removed by air displacement. This is done by inserting a knife blade between:the side of the glass and the gel. At this point of knife entry air is displaced. By rotating the glass the air will rotate around the gel-and thereby loosen the gel from the glass.

3. Quickly slip the gel from the glass onto a watch plate. After 60 seconds, take the reading.

4. To take a reading the black knob is turned until the tip of the pointer touches the surface of the gel.

5. To read the measurement the vertical column gives the whole number. The number is read at the point where the bottom of the dial meets the vertical column. The dial which rotates horizontally gives the tenth of a number. The total reading, as indicates the percent sag.

REFERENCES to Top

´ ´ Updated: Wednesday, October 31, 2007. ´
´ OSU Disclaimer. ´ ´

1.	Material to be tested must completely fill a Ridgelimeter glass. A collar of masking tape will permit an over fill and gel can be leveled with wire slicer before measuring.
2.	Material must be removed from Ridgelimeter glass without being damaged. For a gelatin gel the gel can be removed by dipping the glass into warm water until the gel loosens from the glass. For pectin, starch and egg gels, the gels can be removed by air displacement. This is done by inserting a knife blade between:the side of the glass and the gel. At this point of knife entry air is displaced. By rotating the glass the air will rotate around the gel-and thereby loosen the gel from the glass.
3.	Quickly slip the gel from the glass onto a watch plate. After 60 seconds, take the reading.
4.	To take a reading the black knob is turned until the tip of the pointer touches the surface of the gel.
5.	To read the measurement the vertical column gives the whole number. The number is read at the point where the bottom of the dial meets the vertical column. The dial which rotates horizontally gives the tenth of a number. The total reading, as indicates the percent sag.