Polymer blend may offer cheaper cumin encapsulation

The research, by scientists from the Institute of Chemical Technology, University of Mumbai in India, indicate that the specific blend containing 4/6:1/6:1/6 of gum arabic/maltodextrin/modified starch could offer industry an alternative to pure gum arabic.

The supply of gum arabic (E414 in the EU), also known as acacia gum because it comes from Acacia trees in the gum belt of Africa, is variable due to political and climatic factors in the primary producing countries like Sudan and Nigeria and this has led to spikes in the price of the ingredient.

Gum arabic, known as the 'Rolls Royce' of gums, is widely used by the food and beverage industry, and the top producers (mainly Sudan) bring about 50,000 tonnes of the gum to the market each year.

Attempts to find an alternative have lead researchers to look into alternatives that could be used as a thickener, adhesive, and stabiliser for food and beverage applications.

The gum is also widely used as a wall material for microencapsulation, but this is again limited by the cost, limited supply and quality variations.

"An area of research of increasing interest is the development of an alternative and inexpensive polymer or polymer blends, which could encapsulate flavours with same or greater efficiency as gum arabic," said the researchers.

Writing in the Elsevier journal Carbohydrate Polymers , lead author Dattanand Kanakdande reports that spice oils and oleoresins, said to offer improved flavour quality over distilled volatile oil, pose a number of problems due to their high concentration.

"Being immiscible in aqueous foods, they do not disperse well into the food matrix.

Also flavour loss occurs when incorporated into dry food mixes during high temperature processing," wrote Kanakdande.

"Besides, they are sensitive to light, heat and oxygen, and hence have a short storage life if not stored properly.

The microencapsulation method seems to be useful to solve these problems."

Blends of gum arabic (TIC Gums), maltodextrin (DE-18, Raptokos Brett & Co) and modified starch (HiCap 100, National Starch) were prepared with the ratios 1/3,1/3,1/3, or 4/6 or one of the constituents and 1/6 of each of the others.

The microcapsules were tested for the content and stability of volatiles, as well as the content of specific constituents after six weeks of storage.

The researchers report that, in general, gum arabic microcapsules performed better than either maltodextrin and modified starch, but was not as effective as the 4/6:1/6:1/6 blend of gum arabic/maltodextrin/modified starch.

"From these results, it is evident that the GA/MD/MS (4/6:1/6:1/6) provided best protection to the cumin oleoresin, in fact even superior than the gum arabic individually, and also its combination with maltodextrin and modified starch," wrote Kanakdande.

The research is in-line with the current trend of food manufacturers to turn to encapsulation technologies as a way of achieving much-needed differentiation and enhancing product value.

Tapping into key and emerging consumer trends with innovative techniques is becoming increasingly important for food manufacturers.

Source: Carbohydrate Polymers February 2007, Volume 67, Issue 4, Pages 536-541 "Stability of cumin oleoresin microencapsulated in different combination of gum arabic, maltodextrin and modified starch" Authors: D. Kanakdande, R. Bhosale and R.S. Singhal