MARTA TOMCZYNSKA-MLEKO
Institute of Plant Genetics, Breeding and Biotechnology, University of Life Sciences in Lublin, Akademicka Street 15, 20-950 Lublin, Poland

Abstract

Protein dispersions with or without sucrose were prepared with addition of different sources of protein: defatted milk, full milk, whey protein concentrate, whey protein isolate and egg white isolate. Carbonated beverages based on sparkling mineral water were obtained (4% protein content). Viscosity and surface tension of the dispersions and stability of creatine in the beverages were measured. Sensory analysis of the beverages was performed. Negative linear correlation between viscosity and flavour perception (R2 = 0.96) and positive correlation (R2 = 0.87) between viscosity and perceived consistency were noted. Storage of protein dispersions and beverages for 30 days at 4°C caused degradation of creatine in the range 21.3-28.9% in comparison to 46.1% in water. A 500 ml serving of designed new beverage would supply 20 g of high quality protein and 5 g of creatine for sportsmen and physically active people.

INTRODUCTION

Well-balanced nutrition is crucial for sportsmen and physically active people. According to rules created by nutritionists, humans should consume 5-6 meals per day with appropriate amount of carbohydrate, protein, fat, minerals and vitamins (1, 2). It is considerably easy to find foods being a good source of carbohydrates with low glycemic index, but foods with high protein content are less numerous. Very often consuming protein is connected with increased carbohydrates intake. To prevent this, and to create very convenient source of protein, many different protein supplements are produced. Usually the following proteins are used: whey proteins, casein and caseinates, egg white proteins, soy proteins and beef proteins. To fulfil better digestibility and less allergenicity, different protein hydrolysates are used (3). Protein supplements are usually produced as powders to dissolve in water or juices. Lately ready to drink supplements are for sale containing 25-60 grams of protein in one container. In some countries (USA, Japan) it is possible to buy these kinds of beverages in drink automats. In South Korea and Japan carbonated beverages with ...