BY-PRODUCTS TECHNOLOGY

Module 3. Processing and utilization of whey

Lesson 24
WHEY BEVERAGES

24.1 Introduction

Production of whey based beverages started in 1970’s and until today a wide range of different whey beverages has been developed. Whey beverages include wide range of products obtained by mixing of native, sweet or acid whey, deproteinised whey and whey powder with different additives like tropical fruits ( but also other fruits like apples, pears, strawberries, cranberries), crops and their products ( mainly bran), isolates of vegetables proteins, CO₂, chocolates, cocoa, vanilla extracts and other aromatizing agents. Whey beverages also includes dietetic beverages, drinks with hydrolyzed lactose, milk like drinks and powder drinks. The prominent type of new whey drinks are based on blends of fruit juices and whey. The main advantages associated with such beverages are the healthful combination of the fruit base, vitamin containing components and the dairy based calcium and whey proteins. The manufacture of whey-fruit juice mixtures can be relatively simple and, therefore, many dairy processors have attempted to enter the beverage market with their, own " variants of the common theme".

Other types of whey-containing beverages currently available in the market include whey proteins fortified whey beverages, deproteinated whey beverages, fermented dairy-type beverages containing whey, and flavoured milk-type products containing whey or whey components. Some of these products may be suitable for marketing in dry form as well. In view of increasing demand of beverage in the form of cold drinks and fruit juices, whey has a promising future in the beverage formulation. As a drink, it can replace much of the lost organic and inorganic salts to the extracellular fluid. It also possesses almost all the electrolytes of Oral Rehydration Solution (ORS), which is invariably used to control dehydration.

24.2 Classification of Whey Beverages

gives the classification of main type of commercial beverage product from whey. Whey based beverages are broadly classified into two categories: Fermented and Non fermented. In this lesson, non fermented whey beverages are discussed in detail.

24.2.1 Plain whey beverages

Plain whey beverages include the mixing of whole whey along with sugar, flavour (either synthetic or natural) and colour. These may or may not be carbonated.

24.2.2 Whey based fruit beverages

Different types of whey based fruit beverages have been prepared. Whey-fruit beverage products marketed in Europe is presented in Table 24.1. These whey based fruit beverages can be classified depending on the type of raw material used and different processing conditions. These are as follows:

24.2.2.1 Whey based natural fruit juice/pulp drink

Whey based fruit beverages are manufactured by mixing of appropriate fruit pulp/ juice or juice concentrate and processed whey . The more sophisticated technological approaches include the painstaking selection of proper flavour or flavour blends, complex whey treatment operations and often the inclusion of additional nutrients to increase the consumer appeal. The common operation for the manufacture of whey based beverage is to blend the whey and fruit juice components, followed by proper heat processing and packaging. The sedimentation problem can be removed by centrifugal clarification to remove all sedimentable casein fine particles (Jelen et al, 1987). The pH adjustment in the heat processed long shelf life beverage is important in order to minimize heat induced whey protein precipitation. A typical feature of these products is their low protein and high total carbohydrate content, often exceeding that of a carbonated soft drink or fruit juice product. This high carbohydrate content is a result of the high lactose content of the whey, which contributes little to product sweetness. The overall character of the successful products resembles fruit juices with a somewhat heavier body; the resulting image may be that of a nutritious, rather than a thirst-quenching beverage. The tetra- pack paper based containers of 200 ml capacities predominate in India, while 250 or 500 ml plastic cups with aluminium foil are being used in western countries.

Table 24.1 Whey - fruit beverage products marketed in Europe

24.2.2.2 Concentrated fruit based whey beverages

Concentrated fruit based whey beverages have been developed to deliver the product in more convenient form, minimize the transportation and packaging requirement and improve the protein content. For preparing such products whey is concentrated in vacuum pan or evaporators, mixed with fruit juice concentrate, sugar and other additives, heat treated and packaged.

24.2.2.3 Fruit flavored drinks

In this type of whey based fruit beverages, different types of fruit flavours are used which may be artificial and natural.

24.2.3 Deproteinated whey beverages

Whey permeate which is obtained during whey protein preparation using ultrafilteration process, can be an ideal starting material for the development of such products. These can be carbonated and non carbonated beverages. All beverages made with whey permeate are higher in electrolytes (Na, K, Zn, Mg, P) compared with commercially available sports beverage.

24.2.4 Whey protein enriched whey beverages

Whey protein is used to increase the protein content of whey based beverages. Swedish Dairy Cooperative developed and marketed a protein rich fruit drink called “Nature’s Wonder”. It was produced by mixing a high-grade whey protein, hydrolyzed lactose and pineapple, orange and passion fruit juices. Similarly whey in the form of high protein dry whey powder or concentrate is used for preparation of both dairy type or fruit based beverages.

24.2.5 Whey based soups

The common sequence of the operation in the development of whey based soup involves blending of vegetable in whey and cooking of corn flour followed by heat processing. The time-temperature combination for cooking of vegetables, corn flour and seasoning is important for proper dispersion of vegetables, gelatinization of starch and flavour perception of soups, respectively. The development of long shelf life soup involves proper sterilization of soup. Whey based soup powders can be manufactured by cooking of vegetables in concentrated whey, mixing of blended vegetables in whey, frying of seasonings, gelatinized starch followed by spray drying .

However, commercial soup powders are available as a result of blending of dried vegetables in gelatinized starch. Paneer and cheese whey were utilized for the potato-carrot-tomato and spinach soups . Cheese whey was preferred for the manufacture of vegetable soups than paneer whey (Singh et al., 1994). The reason could be the low pH of paneer whey that resulted in acidic product not usually compatible with most vegetables. Whey based soups have been reported to be more viscous as compared to water based most probably gelation of whey proteins on heating.

24.3 Conclusion

Beverages and soups based on whey continue to receive a considerable amount of attention nowadays. These indicate the growing awareness among consumers and manufacturers alike for the enormous potential these offered for diversifying product profile. Technological packages are available for wide range of whey based such products and with better understanding regarding the functionality of different ingredients it would be possible to develop “functional” whey products for specific target groups.

Selected references

Jelen, P., Currie, R. and Kadis, V.W. 1987. Compositional analysis of commercial whey drinks. J. Dairy Sci., 70: 892-895.
Parekh, J.V. 2007. Small-scale utilization of whey. In: Dairy India-sixth edition, ed. P.R. Gupta and Sharad Gupta. Dairy India Yearbook, New Delhi: 245-246.
Singh, S., Ladkani, B.G., Kumar, A. and Mathur, B.N. 1994. Development of whey beverages. Indian J. Dairy Sci., 47: 586-590.