Abstract

Over the last few years, the production of plantain has been increasing due to the introduction of some high yielding varieties. Unfortunately, very high post-harvest losses are incurred annually due to lack of appropriate storage technologies. This study evaluated the effect of shea butter as a food-grade wax on the pre-climacteric life and sensory qualities of four plantain varieties (Apem, Apentu,Asamienu and Oniaba). Waxing was achieved by brushing shea butter on fruits surfaces. The fruit diameter before waxing (d₁) and after waxing (d₂) was measured and the difference (d₂-d₁) taken as the waxing thickness. Parameters assessed were the uniformity of ripening, gloss quality, incidence of off-flavours and disorders. Waxing thickness of 0.5 and 1 mm resulted in irregular ripening, green-soft disorder and off-flavours. However, thin layer waxing (<0.05mm) prolonged the pre-climacteric life to 22, 20, 17, and 15 days in Apem, Apentu,Oniaba and Asamienu respectively. A prolonged post-climacteric life from 4 to 6 days across varieties as well as firm texture at senescence was recorded. Shea butter waxing resulted in significant decrease (P<0.001) in physiological weight loss of 9.46% by 22 days after storage compared to control which had 21.25% by 10 days of storage. Principal component analysis of sensory attributes showed that mouth-feel, colour, flavour and tastes accounted for 36.67 % of data variation whist texture alone accounted for 21.1% of data variability. Due to increasing lobby against the use of post-harvest chemicals, as consumers now want products with high nutritional value rather than having just superior external qualities, the use of shea butter as a food-grade wax can be further explored since no safety or residual effect is foreseeable.

Key words: Plantain, food-grade waxing, shelf life, sensory qualities.