FDA-Compliant Retort Processing of Indian Milk-Based Sweets such as Gulab Jamun, Rasgulla, Cham Cham.

Indian milk-based sweets like Gulab Jamun, Rasgulla, and Cham Cham hold a special place in traditional cuisine. Known for their delicate texture, syrupy sweetness, and rich dairy flavor, these confections are beloved across the globe. But when it comes to making them shelf-stable and export-ready, especially for regulated markets like the United States, their delicate nature poses significant technical challenges.

This article explores how to make these traditional sweets compliant with FDA regulations using modern retort processing, while still preserving their quality, taste, and appearance.

Cooking and Preservation

The traditional process of preparing these sweets begins with forming soft balls from milk solids either deep-fried in the case of Gulab Jamun, or boiled like Rasgulla and Cham Cham. These are then immersed in a thick sugar syrup with a concentration ranging from 60 to 70 degrees Brix. This syrup not only provides sweetness but also acts as a natural preservative by lowering the water activity to some extent, typically between 0.86 and 0.95. This places these sweet products in the Low Acid Canned Foods (LACF) category governed by 21 CFR Part 113.

Hot-filling is a common method used in domestic production, where the sweets are filled with hot syrup (usually around 90–100°C) into containers and then sealed. Sometimes, these containers are held in hot water showers for additional thermal exposure. While this process can offer shelf lives of 3 to 6 months, it is not sufficient for FDA compliance in the export market, particularly under the Low Acid Canned Foods (LACF) category governed by 21 CFR Part 113.

Although hot-filling followed by hot water shower holding is a viable preservation strategy, especially for local distribution, this article focuses on a retort processing solution.

The Challenge: Bacterial Spores and Low-Acid Risks

From a food safety perspective, these sweets fall into the category of low-acid foods (pH > 4.6), which makes them vulnerable to the growth of dangerous pathogens if not properly processed. Of particular concern is Clostridium botulinum, a heat-resistant, spore-forming bacterium that can thrive in anaerobic, low-acid environments if not effectively controlled.

Other organisms like Bacillus cereus and Geobacillus stearothermophilus are also noteworthy. While the former can cause spoilage and illness, the latter is often used as a benchmark in sterilization studies due to its high thermal resistance.

Because of these risks, simply relying on sugar and hot syrup is not enough. An FDA-compliant thermal process must ensure commercial sterility by either destroying or rendering these spores non-viable under storage conditions.

A Quick Overview of Sterilization and Fo Value

Sterilization in thermal food processing is quantified using the Fo value, a unit that measures the lethality of the heat process, standardized to 121.1°C with a z-value of 10°C. Simply put, an Fo value tells us how much cumulative sterilization a product has undergone. This is most critial factor in retort processing and what we will be studying to ensure proper sterility.

For these types of milk-based sweets with high extremely sensitive profile and color, its not possible to aim for a full commercial sterilization of Fo>3. And with the added sugar content, you don’t necessarily need full sterilization levels. In most cases, a carefully controlled Fo in the range of 0.5 to 2.0 is sufficient to achieve microbial stability without damaging product quality. However, achieving this balance is not straightforward, especially since exceeding 110°C aprox. can cause Maillard browning, caramelization, and texture degradation, making the sweets rubbery and visually unappealing.

Retort Processing and the Role of Heat Penetration Studies

For sweets like Rasgulla or Gulab Jamun, where quality is closely tied to texture and appearance, the thermal process must be designed with precision.

The most important part of process development is the heat penetration study. This is a scientific procedure used to determine the exact combination of temperature and time needed to reach the desired Fo value at the product’s coldest point, typically the geometric center of the sweet ball.

To perform this study, high-accuracy thermocouples/wireless data loggers are inserted into the core of the product and monitored. Systems such as Ellab’s TrackSense or E-Val Pro are industry standards for capturing temperature with high precision.

Multiple batches are run at varying temperatures, usually between 90°C and 110°C and the internal temperature of the product is monitored throughout the come-up, holding, and cooling phases. The data collected is then used to calculate lethality curves and determine how efficiently heat is transferred to the product’s cold spot.

The goal is to identify a processing condition that achieves the desired Fo value without damaging the product. It’s a process of trial and refinement. Variables like syrup viscosity, product size, packaging type (pouches, cans, or glass jars), and fill weight all play a role in how heat penetrates the product.

Once an optimal condition is found, it is a full validation study including a Temperature Distribution Study (TD) and Heat Penetration Study(HP) are conducted, and the process is documented for regulatory submission.

Filing for FDA Compliance: SID and FCE

After proper validation studies, the next step is regulatory filing. To export these products to the U.S., your facility must be registered with the FDA and obtain an FCE (Food Canning Establishment) number. Then, each product and packaging combination must be assigned a unique SID (Scheduled Process Identification) number.

The submission includes detailed information about the product, packaging, processing conditions, equipment used, and the results of heat penetration studies. This documentation ensures that the product can be safely manufactured under controlled conditions that meet FDA requirements.

Conclusion

Developing an FDA-compliant retort process for milk-based Indian sweets like Gulab Jamun and Rasgulla is a complex but achievable task. With careful attention to heat sensitivity, microbial safety, and scientific process development, these traditional sweets can be transformed into safe, shelf-stable products suitable for global markets without compromising their authentic taste and texture.