Impact of Inulin Extracted, Purified from (Chicory and Globe Artichoke) Roots and the Combination with Maltodextrin as Prebiotic Dietary Fiber on the Functional Properties of Stirred Bio-Yogurt

Inulin is a prebiotic dietary fiber that plays an integral role in producing functional dairy products with improved health benefits. Therefore, the objectives of this study are as follows: extract and purify inulin from chicory roots and globe artichoke roots;evaluate the physicochemical, functional properties and functional groups of the purified inulin;determine the functional properties of chicory roots inulin-maltodextrin and globe artichoke roots inulin-maltodextrin and compare it with that of the commercial inulin;examine the impact of various inulin on physiochemical, microstructural, textural, sensory characteristics and as prebiotic dietary fiber on probiotic bacteria’s viability of stirred bio-yogurt. The characteristics of the microstructure were investigated by scanning electron microscopy and, Fourier transforms infrared spectroscopy to detect the functional group. The resulting inulin exhibited a high yield and purity along with enhanced functional properties. Stirred bio-yogurt fortified with chicory roots inulin or globe artichoke roots inulin showed enhanced physicochemical, microstructural, microbiological, and overall sensorial acceptability followed by chicory roots inulin-maltodextrin or globe artichoke roots inulin-maltodextrin and the commercial inulin as compared to the control. Stirred bio-yogurt samples can offer various health benefits and wide applications as supplement of prebiotic dietary fiber in dairy industry.

Biological Studies on Bio-Yoghurt Fortified with Prebiotic Obtained from <i>Jerusalem artichoke</i>

Inulin, an oligosaccharide produced by several plants, has been shown to enhance the viability of probiotic cultures in milk through storage. Jerusalem artichoke ( Helianthus tuberosus L.) is an interested prebiotic because its tuber has risen content of inulin and fructo-oligosaccharides. This study was aimed to: 1) set the effect of Jerusalem artichoke in deferent concentrations (2.5% & 5%) on the growth of probiotic Lb. acidophilus P106 in the bio-yoghurt during cold storage at 5℃ and sensory evaluation of probiotic yoghurts;2) study the effect of feeding with this synbiotic fermented milk on diabetic mice. It could be concluded that the Jerusalem artichoke influenced the growth of Lb. acidophilus P106 and 5% (w/v) Jerusalem artichoke was given the highest growth and sensory evaluation. On the other hand, no serious adverse effects were observed;the reduction of blood glucose was observed at the termination of empirical phase, also, high level (5%) of Jerusalem artichoke led to more reduction of blood glucose, cholesterol levels and total lipids compared with control.

Quality and Sensory Properties of Reduced Fat Yoghurt Made with Addition of <i>β</i>-Glucans

β-Glucans, isolated from Pleurotus citrinopileatus mushroom, were used in the manufacture of yoghurt from reduced fat cow milk with added proteins. β-Glucans were added to the milk in the form of a paste containing 1.21% (on a dry weight basis) of β-glucans, such that the final concentrations in the yoghurt were 0.3%, 0.4% and 0.5%. Control yoghurt was also manufactured from the same milk without the addition of β-glucans. The resultant yoghurts were examined for their physicochemical and microbial characteristics, gel formation and sensory properties and compared to the control at 1, 7, 14 and 21 days of storage. Results showed that the microbial population, pH, titratable acidity, ash and syneresis were not affected by the addition of different levels of glucans. The lowest fat, total solids and protein contents were recorded in the yoghurt containing 0.5% glucan. The yoghurt containing 0.3% β-glucan had the same viscosity as the control and the yoghurt containing 0.5% β-glucan had the lowest viscosity. Yoghurt with β-glucans received slightly higher scores for flavour, appearance and texture than the control. It was concluded that the incorporation of 0.3% or 0.4% β-glucans isolated from edible mushrooms, into the yoghurt does not affect the final product, which is similar or sensorially even better than the control.

Buffalo stirred yoghurt fortified with grape seed extract:New insights into its functional properties

Grape seed extract(GSE)is considered one of the major byproducts,which are rich in phenolic content and possess several health-promoting activities including antibacterial,anticancer,and antioxidant.The current research was devoted to improve the bioactive properties of stirred yoghurt through supplementation with GSE at three concentrations(0.1,0.25,and 0.5 g/100 g yoghurt).The obtained stirred yoghurts were analyzed for determining their composition,pH,syneresis,viscosity,and sensory evaluation.Furthermore,some functional properties including antioxidant,antibacterial,anticancer activities were estimated.Significant increments(p≤0.05)were observed in total solids,ash contents,pH,water holding capacity,and viscosity values,especially when 0.5%GSE was added.Moreover,adding 0.5%GSE showed higher(p≤0.05)in vitro antioxidant,antibacterial,and anticancer activities.Interestingly,the improved bioactive properties resulting from adding GSE,even at the higher concentration,were not accompanied by any change in sensory properties.In particular,the color descriptor was mostly preferred by panelists when 0.5%GSE was added.The assessors did not observe any off-flavors in any of the tested stirred yoghurt samples.Therefore,the functional properties of stirred yoghurt could be improved by adding GSE preparation without affecting its organoleptic properties.