Innovation in Tigernut (Cyperus Esculentus L.) Milk Production: In Situ Hydrolysis of Starch.

Djomdi Djomdi,Philippe Michaud,Richard Ejoh,Cedric Delattre,Robert Ndjouenkeu,Guillaume Pierre,Thierry Tran,Olivier Gibert,Bakari Hamadou

doi:10.3390/polym12061404

Abstract

Tigernut tubers (Cyperus esculentus) are used for the production of vegetable milk, commonly known as “Horchata de chufa” in Spain. The presence of starch in the tuber limits the yield of the milk, since this carbohydrate gelatinizes during the pasteurization of the milk and leads to the considerable solidification of this drink. The present work aims to improve the yields and extraction practice of the milk by an in situ hydrolysis of starch, using exogenous amylases of industrial or vegetable origin. The obtained results show that sprouting improves the extraction yields of tigernut milk, which goes from 50% to about 70%. This improvement in milk yield corresponds to a hydrolysis of about 35% of the starch in the tuber. The use of exogenous amylases leads to starch hydrolysis rates of 45% and 70%, respectively, for amylolytic extracts from sprouted tigernut tubers and amylase, with the corollary of a natural increase in the sweetness of milk. This technical approach makes it possible to produce a naturally sweetened tigernut milk which easily lends itself to pasteurization without a significant increase in viscosity.

Highlights

Tubers are foodstuffs that contain more starch, by dry weight, than almost all other food crops [1].Many authors have shown that Cyperus esculentus L. is an edible plant which produces tubers containing an important starch quantity [2,3,4]
The experiments were carried out on tigernut tubers Ø > 1 cm bought in the market from the locality of Guili (Mokolo, Savannah Region of the Far North of Cameroon)
The tubers were subjected to soaking treatments in vitamin C solution (SVT), and part of the soaked tubers was subjected to sprouting (ST)

Summary

Introduction

Many authors have shown that Cyperus esculentus L. is an edible plant which produces tubers containing an important starch quantity (about 30–40%) [2,3,4]. These tigernut tubers are used in Spain for the production of a milky drink called hochata de chufa [5,6]. This drink does not lend itself well to thermal sanitation treatments due to the gelatinization and retrogradation of its starchy component during pasteurization and cooling. Sugar is added at the drink to improve the taste

Objectives

Methods

Results

Conclusion