ABSTRACT

This study evaluated the effect of packaging materials and storage conditions on stability of three indigenous soups of South South Nigeria. The soups namely Afang, Edikang Ikong and Afere Ndek Iyak soups were packaged in Plastic, Polyethyelene bags and Aluminum pouches and stored at ambient, refrigeration and freezing condition for five months. Soups were evaluated for quality changes monthly. Response Surface methodology was used to evaluate the performance of the packaging materials, the storage temperature and the soups. Some of the quality indices evaluated were the proximate composition, the vitamins and mineral elements. Others were the free fatty acids, thiobabituric acid, total soluble solids and microbial analysis. The soups in freezing and refrigeration storage were analysed monthly while those in ambient storage were analysed daily.  The soups stored at ambient temperature had microbial counts beyond acceptable limits (10⁵cfu/g) after 24 hours, irrespective of whether it was packaged in plastic, polyethylene bag or aluminum pouch. The soups stored in refrigeration condition had significant (p< 0.05) microbial and chemical deterioration after two months storage and were discarded, while those in the Freezing storage lasted five months. The proximate composition of the soup showed that: Protein ranged from 4.32 to 5.77%, Fat 4.30 to 10.86%, Ash- 2.33 to 2.88, Moisture- 76.26 to 82.07%. The micronutrient composition of the soups was: Iron – 0.6 to 0.87 mg/100g, Calcium- 170.88 to 186.94mg, Vitamin B1- 0.26 to 0.77mg/100g, Vitamin C- 16.39 to 29.29 mg/100g. The physicochemical properties of the soup were thus:  Free Fatty Acid- 1.29 to 2.55%; Thiobiaturic Acid- 0.032 to 0.046%, Peroxide value- 1.785 to 2.880 mg/kg, pH- 6.33 to 6.69, Total Soluble Solids- 2.795 to 3.570%. The microbial properties indicated that Total Fungal Count (TFC) ranged from 1.75 x 10³ to 6.0 x 10³cfu/ml while Total Viable Count (TVC) ranged from 8.35 x 10³ to 14.95 x 10³cfu/ml. The shelf life was studied using physicochemical properties, all the soups had similar trend after storage for five months but optimization using Response Surface Methodology showed that Afere Ndek Iyak, Polyethylene bag and Freezing was the best.