Stable Bleaching Powder: A Game-Changer for Sericulture Farmers

Grasim’s Stable Bleaching Powder (SBP) is becoming a popular disinfectant among silk farmers in Maharashtra.

Written by:

Rajendra Parab, Panchakshari Swami and Mehul Patel, GCA Sales and Marketing.

Introduction to Sericulture

Sericulture, or silk farming, is one of the fastest-growing agricultural segments in India today. It has spread extensively across southern and northeastern India and is also gaining popularity among farmers in Maharashtra, who are making remarkable efforts to expand this sector.

Sericulture involves the organized and professional rearing of silkworms. Silkworms are carefully nurtured through their life cycle until they form protective cocoons made of protein-based fibres. These cocoons, small white balls that harden upon contact with air, are collected and processed to produce silk.

Importance of Disinfection in Sericulture

Over the years, Indian sericulture has adopted various modern farming practices to improve crop quality, yield, and the number of harvests per year. This places pressure on farmers to ensure that every crop of silkworms grows in a healthy, well-maintained environment. Disinfection of rearing houses and equipment is one of the most critical factors for achieving healthy silkworm growth.

Several disinfectants are available in the market, and Stable Bleaching Powder (SBP) is one of the most widely used. Research from Indian sericulture institutes also recommends bleaching powder as a suitable disinfectant for silk farming.

Grasim Industries Ltd. has been India’s leading manufacturer of high-quality SBP for over 40 years. Our SBP is widely used across the country to maintain high standards of disinfection and hygiene in multiple sectors — from drinking water treatment (to prevent the spread of waterborne diseases) to hospitals, hotels, malls, and residential colonies. Additionally, SBP is highly popular in prawn aquaculture, ensuring hygienic cultivation of prawns, a seafood delicacy enjoyed worldwide, including in India.

Why SBP is the Preferred Disinfectant

• Chlorine has been the world’s most effective disinfectant for many years. However, handling chlorine gas requires strict safety measures. SBP, a chlorine-based compound that provides about 35% available chlorine, is far safer and easier to handle.
• Like chlorine, SBP offers broad-spectrum effectiveness against microorganisms.
• At recommended doses, SBP targets harmful organisms without causing significant harm to humans or the surrounding environment.
• it is easy to use and apply.
• it has a long shelf life and requires simple storage.
• it is affordable and widely available compared to other disinfectants.
• it is produced by reputed companies like Grasim, which also provide technical and practical guidance to farmers.

SBP Chemistry & Mechanism of Action

Stable Bleaching Powder (Ca(ClO)â‚‚) reacts with water to form calcium hydroxide (slaked lime) and hypochlorous acid (HOCl). HOCl then decomposes to release chlorine, a powerful oxidizing agent.

- Chlorine destroys bacterial cells through irreversible oxidation of their cell walls, leading to immediate cell death.
- Hypochlorous acid diffuses through the cell wall and disrupts metabolic processes, further ensuring microbial death.

This dual mechanism makes SBP highly effective against microorganisms without allowing them to develop resistance.

General Guidelines for Preparing SBP Solution

To prepare a chlorine solution from SBP, use the following formula:

Grams per litre (g/L) = ( % of diluted solution desired × 1000 ) ÷ ( % of available chlorine in SBP )

Note: The available chlorine content (usually around 35%) should always be checked before preparing the solution. Lower chlorine concentration requires a higher quantity of SBP.

Materials required:
• Clean 15–20 L plastic bucket (preferably with volume markings)
• Clean water (filter through cotton cloth if needed)
• Wooden stirring rod (avoid painted or polished materials)
• SBP powder (stored in airtight plastic containers)
• Plastic measuring spoon (with gram markings or fixed capacity)
• Safety goggles, apron, and gloves
• Clean white cotton cloth

Procedure:
1. Calculate the required water volume and SBP quantity.
2. Add the measured water into a clean bucket.
3. Stir in the required SBP with the wooden rod until a milky white solution forms.
4. Wait a few minutes, then filter the solution through cotton cloth into another clean bucket.
5. Use the filtrate immediately.

Important safety notes:
• Prepare fresh solution daily; do not store as chlorine dissipates quickly.
• Use only clean water, as impurities reduce effectiveness.
• For best results, water pH should be below 8.
• Prepare solutions in a well-ventilated area, away from children and animals.
• Always wear protective gear (goggles, gloves, apron).
• Store SBP in airtight containers in a cool, dry, ventilated place, away from other chemicals.
• Refer to the Indian Standard: Stable Bleaching Powder — Code of Safety (IS 15738:2007) before use.

Summary

Bleaching Powder (SBP) is a proven, cost-effective, and widely recommended disinfectant in sericulture farming. It ensures healthy silkworm growth, resulting in high-quality raw silk. Its affordability and availability make it a preferred choice among farmers.

Grasim manufactures SBP at five world-class facilities across India, ensuring top-quality products with at least 34% available chlorine — higher than many alternatives in the market. To further support farmers, Grasim now offers SBP in smaller 5 kg packs and provides technical guidance to help farmers maximize its benefits.