The Effect of Pre-Treatments on the Growth of Aspergillius Niger Mold on Dried Apples

The objective was to determine the effect that citric acid, honey, and salt pre-treatments have on the Aspergillius Niger mold growth on dried apple slices. The importance of applied biology to food nutrition and health can lead to fix malnutrition and improve the safety of preventing mold and bacteria growth on dried fruits and vegetable.  Global aid companies could also drop off these supplies or use these pre-treatments when passing out food to villages and poverty stricken areas.

Measuring the mold growth by subtracting the initial amount from the final amount in mm2, six trials of five apples each pre-treatment were conducted for the three pre-treatments and control.   Three factors were being tested: citric acid, honey, and salt. A control with no pre-treatment was also tested to determine the validity of the experiment. The growth of the mold for each pre-treatments tested was averaged. The researcher applying the Aspergillius Niger mold put a consistent amount of 75mm2 on each apple. The plastic containers provided an ideal storage and transportation environment for the apples.  The room temperature was ideal for growth of the mold.  The apples were left in plastic containers for four days as determined during pre-trials and research that this was ample time for mold to grow.

The best growth preventer was produced by the citric acid pre-treatment with an average of 27.3333 mm2 growth.  The worst growth preventer was produced by the salt pre-treatment with an average of 36.5333 mm2 growth.  A two sample t-test was conducted to prove if one pre-treatment was significantly better than the other pre-treatments.  It was determined from the two sample t-test that no pre-treatment was significantly better than the other pre-treatments.  This means all the pre-treatments tested will prevent mold growth the same.

Research Conducted By:

Max Edwards
Sterling Heights High School

Destiny Kacir
Sterling Heights High School