It is interesting to select and identify probiotic cultures of either yeasts or lactic acid bacteria and to be able to ferment and protect food.You should investigate
1. Probiotic capability of the isolated cultures from foods or other sources such as tolerance to bile and acidity , growth, production of enzymes and bacteriocins...etc.
2- Select the best in step 1 and test for starter ability to ferment certain foods
3- Choose the antimicrobials producers which can attach smooth surfaces of experimental rats or other animals.
The most common research around food sciences usually about packaging effects, storage duration, or food preservatives.. I recommend to find an alternatives way with the same function as sodium nitrite instead of using sodium nitrite.
Thank you. As you are honors level student, when you post this type of question, it is important to mention a framework in including available facilities and time farm.