EFFECTS OF SOME NATURAL PRESERVATIVES ON THE NUTRIENT COMPOSITION AND SHELF LIFE OF SMOKED TILAPIA SPECIES (Oreocromis niloticus)

Abstract

The effects of some natural preservatives on the nutrient composition and shelf life of smoked tilapia species (Oreocromis niloticus) was evaluated. Three natural preservatives Syzygium aromaticum, Myristica fragrans and Piper guineense were used in their powdery form at (10%) inclusion rate to coat tilapia species before smoking. Thesmokedtreatedtilapiafishsampleswerestoredfor8weeksandanalyzedfornutrientandshelflifeparameters using standard methods. Results of the nutrient composition showed significant differences (P<0.05) in nutrient retention among treatments throughout the storage period. The clove treated smoked tilapia species lost 2.41% crude protein, nutmeg treated smoked tilapia lost 1.70%, black pepper treated smoked tilapia was reduced by 9.03% while control had a significant (P<0.05) loss of 22.8% of its crude protein value. Clove treated smoked tilapia recorded highest lipid value (57.72%) while the control has lowest lipid percentage (31.70%). The ash content was significantly higher (P<0.05) for nutmeg treated smoked tilapia (93.5%) while the control gave an increment of (27.62%). The clove and nutmeg treated smoked tilapia species had moisture increment by (87.75%) and (89.07%) respectively while the controlhas the lowest moisture increment (53.88%). The nitrogen free extract (NFE) was significantly low for nutmeg treated smoked tilapia (49.16%) while the control had the highest value (61.72%). The result indicated that nutmeg treated smoked tilapia gave a high nutrients retention followed by clove treated smoked tilapia. All treatments including the control did not develop insect attack during the study period which is a function of good shelf life. Therefore, it is recommended that, for better nutrient retention of preserved smoked tilapia species and extended shelf life, Myristica fragrans can be used.