Test Strips are Immersed Directly in Oil for Immediate Information

Each kit consists of a supply of the test strips ready to us, and a comparison chart that can be used to evaluate the color response of the strips.  Strips are dipped into the oil to be tested, and the color response immediately produce an easy to read color indication. 


Strips are dipped into the cooking oil at cooking temperature, and in seconds, you are able to determine the degree of shortening breakdown.

Color Indication of FFA is a Measure of Quality

Shortening quality is measured by "free fatty acids" or FFA.  The higher the FFA, the older and "more used" is the cooking oil (see note below).  Every cooking oil has a life cycle:

Early in the cycle, the quality of fried food is not the best, as there is conditioning of the oil to achieve the best taste and texture result.  This break-in period is brief, and soon the oil is at a fresh to optimum cooking level.  As the oil gets older, it continues to break down, producing discoloration of the cooked food, and eventually bad flavors and rancid aftertaste.  This entire cycle can be tracked chemically by determining the level of the FFA's using our test strips.    

A. Break-in Oil

White appearance of oil; no odors in cooked food; very little oil soak up by food materials.

B. Fresh Oil

Slight browning at the edges of the fry; crisping, more oil soak up by food materials.

C. Optimum Oil

Golden brown color; good crisping; optimal soak up by food materials.

D. Degrading Oil

Darken fry with too crisp edges, spots and hardening.  Too much soak up.

E. Runaway Oil

Hard rock fry surfaces; bad odor and too much oil soak up.  Uneven cooking.

Clearly, any operation will produce a better food product if oil is renewed as soon as it reaches the end of phase "C" in this cycle.  The only way to really do this is to measure the condition of the oil by measuring FFA's, and the only way to do this in the kitchen or commissary is using a test strip.

How to Use and Interpret the Strips

Our normal strips correspond to the above cycle, and can be interpreted* to make good decisions about your cooking oil's condition. Color bands run from good to bad, running from top to bottom. The lowest reading (2.0% FFA) is indicated when only the lowest color band has changed color from blue to yellow.  Each successive band that changes color from blue to yellow indicates a higher level. The highest level is 7.0% FFA or above.  This is indicated when all four color bands are yellow. These stages correspond to the oil cycle above in an overall sense, but depend upon the type of oil, temperature of cooking, and other factors.  Generally however, the guidelines to follow are as follows:

Stage 1. OK, past the break-in period and going towards fresh oil or optimum.

Stage 2. Probably OK, but check food quality.

Stage 3. Probably NOT OK, but if food quality is good, keep using the oil.  Use the "if in doubt, throw it out" rule.

Stage 4. Bad oil.  Discard it.

Low Range Monitoring Strips

Low level strips are used where regulatory requirements call for a lower range, or where the importance of quality is extremely important--generally food processing applications will require the low range.  Retail food preparation generally will do well with the higher range--high volume food processing is better with the low range. > 2.5% FFA > 2.0% FFA > 1.5% FFA > 1.0% FFA The scale in the critical transition from optimum to degrading is much finer, allowing complete control over oil quality in processing operation, and control over cooking results with particularly sensitive or delicate food types.  In these operations, a reading of >2.5% would call for oil renewal, while the readings at 1.0% through 2.0% FFA would indicate how close the operation is coming to a need for renewal.




Strip Type Choice Guide

Internal quality guidelines or mandated or recommended Federal Food Programs will specify levels of FFA that are acceptable.  In these cases, the choice is simple: purchase the strips that will give the needed monitoring results. Otherwise, here is a practical guide to what strips are best for your operation:  

Operation Best Strip Type
Processor Low Range
Seafood, Chicken Low Range
Fries, breaded vegetables and  breaded meats Regular
Un-breaded foods Regular
Retail Food Prep Regular

This chart is based on feedback from our customers, and is in keeping with generally accepted industry practice.

  *Note: The values produced by the strips are equivalent to official A.O.C.S. procedures Te 1a-64 and Ca 5a-40.