Sweet residues
AGRO-PROCESSING industries playa pivotal role in both the agricultural and industrial sectors. They provide links between agriculture and industry. The present wave of globalisation has had more influence on agriculture in general and agro-processing in particular. Progress in science and technology has resulted in the viable utilisation of by-products from agriculture through value addition. As a result, the value of raw materials has increased and environmental hazards have been prevented.
The book is a detailed account of sugarcane and its processing in the country. Besides sugar and jaggery, sugarcane supplies a wide range of by-products like molasses and bagasse to 25 industries. The book has 30 research papers grouped into 10 sections. Each section takes a look at different issues like bagasse, energy, fodder, effluent treatment and sugar complexes. The important technical aspects involved in processing have been explained in each paper.
Although India is the second largest producer of sugarcane in the world - next to Cuba - the processing of sugarcane has not been developed to the desired levels. According to the authors, this is due to the lack of technical personnel and resources. Advancements made by other countries in this area have been cited in appropriate places, and this would help policymakers suggest suitable guidelines. Nonetheless, India has some remarkable achievements to its credit. For instance, a public sector unit located in Pugallur in Trichy district of Tamil Nadu was the first in the world to produce newsprint using bagasse pulp.
Sugarcane is often blamed for being a water- guzzling crop. But, it provides food, fodder, fuel and feed. Given the situation, cost-effective methods to use such products have to be developed. From the papers, one gets an impression that currently available sugarcane-processing technology is not economically viable.
The section on food, fodder and feed is interesting and highlights methods to recycle sugarcane by-products. In India, the available fodder and feed are not sufficient to meet the nutrient requirements of the growing livestock population. Sugar- cane thrash (the residue obtained after extraction of pulp) provides fodder for livestock and can be processed and kept for a long time, for use during the slack season. Another area where sugarcane thrash can be viably used is mulching. Mulching not only helps proliferate useful organisms present in the soil, but also increases its capacity to retain water. Normally, the farmers simply burn thrash immediately after the harvest and this kills the beneficial organisms already present in the soil.
Another area which needs attention is effluent treatment. Due to a lack of proper effluent treatment and disposal, the environment is affected. In many sugarcane belts, this has led to quarrels and tension between the locals and sugar mill authorities. Some articles analyse effective effluent treatment techniques in the areas of paper, distillery and sugarcane crushing. The last section examines how best an integrated approach for sugar agro-industrial complexes can be developed.
The volume, which contains many technical concepts, may be a little difficult for the lay person to understand. Secondly, the data presented in many of the papers has not been updated. Barring these shortcomings, the book shall be useful to persons interested in the field.