Department of Livestock Products Technology, College of Veterinary Science, S V Veterinary University, Rajendranagar, Hyderabad-500 030, Andhra Pradesh, India.
*For correspondance:hyd2_kkreddy5@sancharnet.in
An attempt was made to estimate the oligosaccharides content in fruits, vegetables and edible roots and to find the effect of drying on different oligosaccharides (stachyose, raffinose, maltotriose, maltotetraose, maltopentaose, maltohexaose and maltoheptaose) considering their importance as prebiotics (substrate for the growth of probiotics in human colon). Quantification involved hot water extraction (98°C/2 h) of oligosaccharides, different filtration steps, followed by high performance liquid chromatography (HPLC) analysis using 70% acetonitrile as eluent with refractive index (RI) detector and oligosaccharide standards as reference. Raffinose content was observed (mg/g of DM) in okra (0.089), onion (0.3015) and potato (in trace amounts). Stachyose content was noticed (in mg/g of DM) in apple (traces only) Maltotriose content was observed (mg/g of DM) in onion (0.1148). Maltotetraose content was observed (mg/g of DM) in beet root (0.2394), okra (traces), onion (0.105), garlic (0.3075), guava (0.0678) and banana (0.177). Maltopentaose content was found in three samples (mg/g of DM) in yam (traces), garlic (0.3929) and tomato (0.549). Maltohexaose content was present (mg/g of DM) in carrot but only in traces. Maltoheptaose content was not found in any analysed samples (fruits, vegetables and roots). Drying had no effect on enzymatic hydrolysis of different oligosaccharides compared to fresh samples. Carrot, okra, onion, garlic, beet root, yam, guava, apple, tomato and banana appear to be good sources for commercial extraction of prebiotics by using membrane processing technology.
Fruits, Vegetables, Roots, Oligosaccharides, Prebiotics, HPLC
