RITA FIAGBOR, RABIN GYAWALI, ROBERTA CLARO DA SILVA, HEATHER COLLERAN, SALAM A. IBRAHIM*
*Corresponding author
Food and Nutritional Sciences Program, North Carolina Agricultural and Technical State University Greensboro, USA

Abstract

In this  study, we investigated the impact of tiger nut extract (TNE) supplemented with dairy proteins (whey protein concentrate, WPC; and sodium caseinate, NaCN) and pectin gum on the growth of the probiotic bacterium, Lactobacillus rhamnosus GG (ATCC 53103). The bacterial populations in supplemented tiger nut media were determined  after 12 h of incubation at 37°C. TNE with both protein types supported the growth of the LGG strain. A maximum bacterial population of 7.76 log CFU/mL was reached in the TNE medium supplemented with 1.0 % WPC and 0.1% pectin. This growth was comparable to the population reached in a tested standard growth medium such as MRS. However, increased concentrations of protein did not have a significant effect (p > 0.05) on the bacterial growth. The results thus indicated that TNE could serve as an acceptable growth substrate for the cultivation of probiotic strains.

INTRODUCTION

Tiger nut (Cyperus esculentus L.), also known as “chufa”, edible cyperus, rush nut, earth almond, groundnut and edible galingale, is a perennial crop grown extensively in Tropical and Mediterranean regions. It is consumed under different forms in West and Central Africa: unprepared, soaked in water or dried and mixed with roasted groundnut (1, 2). The nut is nutritious, and has found wide application in food technology. The best-know application of tiger nut is the production of a milky beverage called “horchata de chufa.” (3).  It has also been used as flavoring in ice cream and bakery, in the preparation of a nonalcoholic beverage with low viscosity, a sweet-acidic taste and a milky appearance (4). In recent years, tiger nuts have been investigated regarding their potential use in developing functional foods such as probiotic drinks (3, 5). Consumption of probiotic L. rhamnosus has shown to enhance systemic cellular immune responses and may be useful as a dietary supplement to boost natural immunity (6).

Interest in a tiger nut extract (TNE) has emerged not onl ...