Title:Evaluation of Consumer Sensory Acceptability and Shelf Life of Orangefleshed Sweet Potato-enriched Mozzarella Cheese
Volume: 17
Issue: 7
Author(s): Nixon Kebeya , John M. Nduko *Patrick S. Muliro
Affiliation:
- Department of Dairy, Food Science and Technology, Egerton University, Egerton,Kenya
Keywords:
Mozzarella cheese, sensory analysis, orange-fleshed sweet potato, shelf life, functional food, dietary fibre.
Abstract:
Background: Consumer interest in convenience foods is a new trend worldwide that is
expected to increase due to busy lifestyles. Studies have shown that sweet potato has unique
nutrients, which if incorporated into cheese, can make it a functional food. Food product
development process requires that before a product is commercialized, it is subjected to consumer
acceptability and shelf-life tests.
Objective: The objective of this study was to determine the sensory acceptability and shelf life of
mozzarella cheese that was enriched with orange-fleshed sweet potato to improve fiber content.
Methods: Mozzarella cheese was prepared with orange-fleshed sweet potato powder at 0% up to
5.5% at intervals of 0.5% and a seven-point hedonic scale was used to evaluate product
acceptability based on colour, aroma, acidity, texture, and fibrousness. Cluster analysis and
principal component analysis were carried out using Minitab® software. For shelf life, total
coliform count, E. coli, and yeasts and moulds counts were used.
Results: Hedonic scores for all sensory attributes except color were not significantly (p>0.05)
different between control and treatments. Cluster analysis grouped the sensory attributes into 3
clusters (1-color; 2-aroma, texture and fibrousness; 3-taste and acidity). All the sensory attributes
loaded positively on component 1, while taste, acidity, and fibrousness loaded negatively on
component 2 of principal component analysis. Fresh cheese had no coliforms, E. coli, yeasts and
molds. The yeasts and molds were used to predict shelf life and their numbers were directly
proportional with the cheese storage period. The control samples had the longest predicted shelf
life of 42 days and the shelf life decreased with increase in orange-fleshed sweet potato
incorporation with a treatment of 5.5% orange-fleshed sweet potato having 29 days.
Conclusion: Orange-fleshed sweet potato (OFSP)-enriched mozzarella cheese had similar
sensory acceptability as the control without OFSP. It should therefore be promoted as a
functional food with a possibility of using food grade anti-mold agents for extended shelf life.
