Efficacy of blanching in removing bitter aftertaste, nutrient retention, and saponins of Asparagus racemosus (Willd.) root powder

Asparagus racemosus (Willd.)has excellent galactogogue and antioxidant activity, and hence has been found very effective in improving lactation performance and being a natural preservative in extending the shelf-life of food products.However, it is endowed with a bitter aftertaste, which limits its utilization in the food industry.Efforts have been made to remove the bitter aftertaste of A. racemosus powder and to enhance mineral bioaccessibility through blanching.Blanching of A. racemosus roots was done at various time and temperature combinations, i.e., 80ºC, 90ºC, and 100ºC temperatures for 5, 10, and 15 min, respectively.The taste of the developed powder with or without blanching was analysed by a panel of 30 semi-trained judges.The effect of blanching on saponins, antioxidants, nutrient contents, and mineral bioaccessibility was analysed using standard methods.Blanched root powder (80 o C for 15 min) had higher total soluble sugars (35.66%) and retained maximum amounts of antioxidants (71.86%) and saponins (5.30%).Blanching at 80ºC for 15 min, developed a mildly sweet aftertaste in the powder and removed bitterness completely.The blanched root powder contained 6.08, 12.67, and 18.75 per cent of soluble, insoluble, and total dietary fibre, respectively.Blanching increased the content of the total and non-reducing sugars significantly in the developed powder.Total calcium, iron, and zinc were found to be 103.24,26.85, and 1.96 mg/100 g, respectively, in blanched root powder and the per cent in vitro bioaccessibility of these minerals were 53.35, 11.66, and 19.39 per cent, respectively.Blanching of A. racemosus roots at 80ºC for 15 min was highly effective in removing bitter aftertaste and better retention of antioxidants and saponins.