Effects of Sun Drying, Shade Drying, Blanching and Cooking on the Nutrient Composition of Turmeric Rhizome (Curcuma longa)

Abstract

The study determined the effect of sun drying and shade drying on the nutrient composition
of turmeric (Curcuma longa). Two kilograms of fresh turmeric rhizomes were purchased
from a local market (Ogige) in Nsukka Local Government Area of Enugu State. The samples
were trimmed and thoroughly washed under running water to remove debris, peeled, and
thinly sliced. The sample was divided into two portions. The first portion was sundried
while the other portion was shade dried. The two samples were processed into powder and
packaged in a well-labeled airtight container for analysis. Association of Analytical Chemists
and other analytical methods were used to determine the nutrient composition of the
samples. Data were analyzed with Statistical Product for Service Solution (version 22) using
ANOVA and Duncan's New Multiple Range test at P<0.05. The findings of the study
revealed that the sun-dried sample had the highest value for carbohydrate (55.51%), ash
(8.03%), and moisture (18.50%) while shade dried sample had the highest protein (8.61%)
and fat (7.21%). The raw shade-dried sample had the highest values for Beta carotene (20.10
mg/100g) and Vitamin C (3.60mg/100g), while the boiled sun-dried sample had the highest
values for potassium (40.82mg/100g), iron (9.79mg/100g) and calcium (595.7mg/100g).
Therefore, sun-drying and shade-drying processing methods on the turmeric should be
encouraged as they conserve more nutrients.