Fermented crackers, soda crackers withstand humidity in similar way.

Crackers are a family of crisp baked goods that have been either chemically leavened or fermented. Soda crackers are a traditional type of fermented cracker. They are produced from a laminated dough. Snack crackers are also produced from a laminated dough. But they have more flavoring added to them and undergo less fermentation.

Crackers are one of the most popular snack foods and are enjoyed by millions in the United States. Two of the most popular crackers in the country are soda crackers and fermented crackers. When they are stored, it is common that the crackers become soggy, especially in humid climates.

On many occasions soggy crackers are discarded even though they are otherwise safe to consume. It is therefore important to learn which crackers stand up better when they are stored and exposed to different levels of humidity.

Scientists at Florida State University placed saturated solutions of KOH, K-acetate, Mg(NO3)2, NaCl and K2SO4 in dessicators at 25 C for 10 days to generate water properties (Aw) of 0.0823, 0.227, 0.529, 0.753 and 0.973, respectively. The crackers were stored in aluminum trays placed inside the dessicators.

The researchers determined the moisture content of the control and experimental crackers by AOAC method 925.40. Cracker texture was determined by using a Bailey shortometer. All experiments were conducted twice. The mean moisture gain was maximum at Aw 0.753 for both types of crackers. Contrary to expectations, both types of crackers gained similar amounts of moisture, particularly at high Aw levels.

Shortometer readings indicated that shear force declined as the moisture increased. Monolayer values for soda and fermented crackers were respectively 0.044 g and 0.024 g of water per g of solids. At Aw of less than 0.529, the crackers remained dry.

The data suggest that both types of crackers behaved in a similar manner regardless of the level of humidity to which they were exposed.

Further information. Shridhar Sathe, Department of Nutrition, Food and Exercise Sciences, Florida State University, 402 Sandels Building, Mail Code 1493, Tallahassee, FL 32306; phone: [phone]; fax: [phone]; email: [e-mail].