ABSTRACT

The general objective of this study was to evaluate the chemical and sensory properties of soymilk produced and stored using different techniques. Soybean seeds were procured from Ubani Main Market in Umuahia, Abia State. Soybean seeds were divided into three portions of 500g each for processing of soymilk using three different techniques (SYM1, SYM2, and SYM3). SYM1 was soaked, bleached for 30 minutes, manually dehaulled, washed milled and simmered for 10 minutes. SYM2 was soaked for 9hrs, parboiled in water for 45 min, dehaulled, washed, milled, pasteurized for 1hr at 85 ^oC and stored at 4-2 ^oC in refrigerator, SYM3 was soaked, for 11 hrs with 3g of sodium bicarbonate, dehaulled, washed, milled, strained with muslin cloth and was stored at ambient temperature 12^oC. The chemical composition and microbial count of products were determined in the laboratory and sensory evaluation of the soymilk samples were assessed by a 20-member panelist using nine (9) point hedonic scale with 1 representing the least score (dislikes extremely) and 9 the highest score (like extremely). Analysis of variance (ANOVA) was performed on the data and mean differences were considered significant at 95% confidence level (p<0.05). Result shows significant differences (p<0.05) in the chemical composition parameters of samples. Moisture content of SYM1 (86.34%), SYM2 (86.46%) and SYM3 (87.46%) were significantly different (p<0.05) from each other. The protein content of SYM2 (3.52%) was higher and significantly different (p<0.05) from SYM1 (3.47%) and SYM2 (3.46%) which had similar values (p<0.05). The fat content of Soymilk SYM1 (1.90%) was significantly different from SYM2 (1.86%) and SYM3 (1.86%) which had similar values. In similar manner, the fibre content of sample SYM1 (0.46%) significantly differed from SYM2 (0.43%) and SYM3 (0.39%). The carbohydrate content of the Soymilk samples, SYM3 (6.06%) was significantly different with SYM1 (7.09%). The energy value of the samples differed with each other significantly (p<0.05). Anti-nutrient content of samples ranges were; Tannins 0.57 – 3.61mg/100g, Saponin 3.51 – 3.57 mg/100g, Phytates: 0.77 – 0.85 mg/100 g and trypsin inhibitor 0.21-0.27 mg/100 mg. Tannin, Saponin, and Phytates in sample SYM3 were significantly (p<0.05) different from SYM1 and SYM2. The calcium (Ca) content of the Soymilk SYM1 (160.11 mg), SYM2 (156.90 mg) and SYM3 (156.90 mg) shows significant differences (p<0.05) from each other. Magnesium (Mg) content of the Soymilk ranged from 14.76 to 15.45 mg/100g and all the samples showed significant differences (p<0.05) from each other. All the samples showed significant differences (p<0.05) in K among each other ranged from 130.67 to 130.88 mg/100g. In similar manner, all the samples showed significant differences (p<0.05) in P content among each other ranging from 102.39 to 102.54 mg/100g. Iron (Fe) content ranged from 0.58 to 0.62 mg/100g and all the samples showed insignificant difference (p>0.05) from each other. The zinc (Zn) content of the Soymilk samples were within the range of 0.24 to 0.30 mg/100g. SYM1 and SYM2 were not different (p>0.05) from each other. However, SYM3 differed significantly from SYM1 and SYM2. Microbial count revealed that the Soymilk samples had less fungal and bacterial count below the acceptable limit as established by regulatory agency. The sensory evaluation showed that the Soymilk samples received general acceptability (cumulative mean value of 7.4). There was no significant difference (p<0.05) in mean response of the panelists on the appearance and mouth feel of the product. However, there were significant differences (p<0.05) in the taste, flavor and general acceptability of the product samples produced and stored using different techniques. This study showed that the Soymilk samples produced and stored using different techniques were nutritious and acceptable to the panelists. More work was recommended to ascertain and improve the shelf life of the Soymilk products.