PREVENTING DISCOLORATION - ASCORBIC ACID SOLUTION
Michigan State University Extension 
Preserving Food Safely - 01600943 
08/03/99 

* While preparing a canner load of jars, keep peeled, 
halved, quartered, sliced or diced apples, apri- 
cots, nectarines, peaches and pears in a solution 
of 3 grams (3000 milligrams) ascorbic acid to 1 
gallon of cold water. This procedure is also useful 
in maintaining the natural color of mushrooms and 
potatoes, and for preventing stem-end discoloration 
in cherries and grapes. You can get ascorbic acid 
in several forms: 

Pure Powdered Form--seasonally available 
among canners' supplies in supermarkets. One 
level teaspoon of pure powder weighs about 3 
grams. Use 1 teaspoon per gallon of water as 
a treatment solution. 

Vitamin C Tablets--economical and available 
year-round in many stores. Buy 500-milligram 
tablets; crush and dissolve six tablets per 
gallon of water as a treatment solution. 

Commercially Prepared Mixes of Ascorbic and 
Citric Acid--seasonally available among 
canners' supplies in supermarkets. Sometimes 
citric acid powder is sold in supermarkets, 
but it is less effective in controlling 
discoloration. If you choose to use these 
products, follow the manufacturer's 
directions. 

* Fill hot foods into jars and adjust headspace as 
specified in recipes. 
* Tighten screw bands securely, but if you are 
especially strong, not as tightly as possible. 
* Process and cool jars. 
* Store the jars in a relatively cool, dark, dry 
place, preferably between 50 and 70 degrees 
Fahrenheit. 
* Can no more food than you will use within a year. 



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