Shelf life enhancement of juvenile shoots of edible bamboos through different processing and preservation techniques and evaluation of their phytochemicals

Abstract

The juvenile bamboo shoots are a traditional underutilized food which is rich in nutrients and bioactive compounds, but have some antinutrients and a very short shelf-life therefore need to be processed and preserved. Presently, shoots of three edible bamboo species viz. Bambusa bambos, B. nutans and D. sikkimensis were evaluated for shelf-life after preservation in different packaging materials (glass bottles, high density polyethylene bottles and low density polyethylene bags) and preservation conditions (raw/boiled shoots and water/brine medium) and their nutritional, anti-nutritional and bioactive profile were determined after various processing and preservation techniques. B. nutans shoots containing minimum antinutrients content thus are best for consumption in fresh form. B. bambos has high bioactive compounds and macromineral elements content. Different processing techniques eliminated the antinutrients content to a safer consumption limit, where 20 minutes boiling and 12 hours soaking treatments are best durations for retaining substantial nutrient composition; fermentation enhanced bioactive compounds and storage period of shoots; freeze drying is best for maintaining original color and structural dimensions with maximum nutrient retention in shoots while sun drying optimally retained bioactive compounds. Overall retention of nutrients and bioactive components was highest in brine preserved raw shoots stored in glass bottles. The antinutrients were almost totally removed during storage. After evaluation based on visual observations and microbial infection, shelf-life and quality of bamboo shoots of all the three species could be enhanced upto 12 months when brine preserved boiled shoots were kept in glass and high density polyethylene bottles (4oC), where the shoots of D. sikkimensis were best for preservation.