DEVELOPMENT OF LOW-FAT YOGURT USING FAT REPLACER (INULIN)

Abstract

The study was conducted to develop low-fat yogurt using skim milk in addition with Inulin (fat replacer) as well as to evaluate physicochemical and sensory properties of the developed low-fat yogurt. The influence of different levels of inulin on the quality of low-fat yogurt production was also investigated. Inulin was added to milk containing 0.2% of milk fat to give inulin levels of 1, 2 and 3% named T1, T2 and T3. The experimental yogurts were compared with control yogurt produced from whole milk with 3.5% of milk fat. The total solids content of milk was standardized by adding skim milk powder to the experimental yogurt. The titratable acidity, pH, chemical composition and sensory evaluation were determined in the experimental yogurts at the 1st and 7th day. In the study moisture, protein and ash% of the samples showed significant difference between the treatments. T2 sample had the highest moisture content 86.74% whereas T3 being the lowest value 86.58%. The moisture% of T3 was significantly better than the other samples. The ash content was recorded higher in our developed samples than our control samples, where highest value of ash content 1.02% was found in the T1 sample followed by T2 (0.95%) and T3 (0.87%). The result showed that the ash% of T1 was significantly better than that of other samples. The protein content was recorded higher in our developed samples than our control samples, where highest value of ash content 4.49% was found in the T1 sample followed by T3 (3.95%) and T2 (3.94%). The result showed that the ash% of T1 was significantly better than that of other samples. The addition of 1%, 2% and 3% inulin to yogurt was slightly affected by its pH and acidity during storage. Sensory properties of the yogurts were evaluated during storage (4°C temperature). The scores of aroma taste and overall acceptability showed no statistical significant difference between treatments. Sensory evaluation, the highest score of taste was recorded in control samples and T3 samples (7.6) than other two T1 and T2 sample group. Among the four groups of sample, highest score of body and texture was given 8 in control samples followed by T3 (7.4), T1 (7.2) and T2 (6.6). The addition of inulin didn’t significantly affect pH and titratable acidity. In case of the organoleptic quality of three groups of low-fat yogurt, yogurt containing 3% inulin (T3) had the highest score (7.5) in overall acceptability. Overall, the yogurt contain 1% of inulin (T1) was almost similar in quality characteristics to control yogurt with whole milk. The better quality of low-fat yogurt can be made by using 3% of inulin as fat replacer as well as 1% of inulin can also be a better choice in case of high ash(1.02%) and protein(4.49%) with best benefit-cost ratio.