The production of jam from indigenous fruits using baobab (Adansonia digitata L.) powder as a substitute for commercial pectin

摘要

Baobab(Adansonia digitataL.)powderhashigh gelling capacity, but its potential has not been exploited.In the present study, baobab powder was assessed as a potential alternative for commercial pectin in jam making. Itsgellingability and potential use was compared to that of commercial pectin in the production of jam from different indigenous fruits available in Tanzania. Jams were produced fromindigenous fruitsobtained fromvarious areas of Tanzaniaincluding,Smelly-berry (Vitex mombassae), Wild loquat(Uapaca kirkiana) and Marula plum (Sclerocarya birrea) usinglemon extract, commercial pectin andbaobab (Adansonia digitataL.)powderas sources of pectin. Total soluble solids (TSS) andtotal titratable acidity(TTA) for fruit pulps and jams weremeasuredto obtain the required acidtosugar ratio for quality jam. Pectin content of the fruit pulps, baobab and lemon extract were also determined. Shelf life of jams stored at room temperature was monitored for six months by determining moisture content, TSS, TTA, and microbiological changes. Sensory evaluation of the jams wasperformedto assess consumers’ preference among theproducedjams.Findings of this study reveal that, TSSranged from11.6% inAdansonia digitataL. to16.9% inUapaca kirkiana.TTA was highest inAdansonia digitataL.(2.27%)and lowest inUapaca kirkiana(0.05%).Pectincontentin fruits was highest inAdansonia digitataL.(2.56%) and lowest inVitex mombassae(0.12%).Jams formulated without addition of pectin were inferior in quality. Commercial pectin and baobab powder produced jams which did not differ significantly (p0.05) in moisture content, TSS and TTA. Jams formulated with commercial pectin and baobab powder were of acceptable quality up to six months. Sensory evaluationrevealedthatjam produced fromSclerocarya birreawas significantly (p0.05) superior in all sensory attributes compared to other fruits. The use of baobab powder as a source of pectin gave high quality jams, which compared favorably with that of commercial pectin.