Comparative study of the effect of dry and wet ginger (Zingiber officinale Roscoe) spice
on the proximate and microbial safety of soybean beverage

Adegbola Oladele Dauda, Olufunmilola Adunni Abiodun*

Department of Home Economics and Food Science, University of Ilorin, Ilorin, Kwara State, Nigeria

original scientific paper
DOI: 10.17508/CJFST.2017.9.2.07


Soybean beverage, most common nutritious local beverage in Nigeria and in the world, is a high protein beverage used as a dairy milk substitute with the limited utilization due to natural or ambient conditions that serve as growth medium for microorganisms. Hence, it has a short shelf life. This study examines the shelf life of soybean beverage preserved with the ginger spice (dried at 70 ˚C, 80 ˚C, 90 ˚C and 100 ˚C, and 2 g and 4 g of fresh/wet ginger respectively) over 7-week period. The samples were (A: plain soybean beverage; B: 200 ml soybean beverage + 2 g of ginger dried at 100 ˚C; C: 200 ml soybean beverage + 2 g ginger dried at 90 ˚C; D: 200 ml soybean beverage + 2 g ginger dried at 80 ˚C; E: 200 ml soybean beverage + 2 g ginger dried at 70 ˚C; F: 200 ml soybean beverage + 2 g fresh ginger; and G: 200 ml soybean beverage + 4 g fresh ginger respectively). The proximate, pH, microbial and sensory analyses of samples ranged as follows: 87.35% – 90.83% for the moisture content; 0.58% – 0.65% ash content; 4.65% – 4.96% protein; 0.10%-0.26% fibre content; 2.06% – 2.98% crude fat and 1.68% – 4.17% carbohydrate, and pH values ranged from 6.2 – 6.5. Microbiological analysis over storage period showed that the control sample ranged from 0.4×106 -8.3×106 cfu/ml, and treated samples from 0.4×106 to 2.4×106 cfu/ml. Low values of the samples treated with dry ginger spice were preserved better than others, probably due to preservative and anti-microbial properties of the spice. Sensory evaluation, carried out by twenty-eight persons, showed that the sample E: (200 ml soymilk+ 2 g ginger dried at 70 ˚C) was most preferred (with respect to taste, aroma and overall acceptability), while there was a significant difference in the appearance of the samples.


Keywords: Soymilk, ginger (Zingiber officinale Roscoe), proximate analysis, microbiological analysis, safety, shelf life, preservation