1.Capsule Shell Integrity:

Brittleness: Temperature fluctuations can render the capsule shell more brittle, especially in cases of sudden shifts from high to low temperatures. For instance, if a hard capsule experiences a rapid drop in temperature, the gelatin may harden quickly, making the shell susceptible to cracking or breaking during handling or transportation.

Softening: Conversely, exposure to elevated temperatures can lead to softening of the capsule shell. This is notable in environments where the storage temperature exceeds the recommended range. Soft capsules may become misshapen, stick together, or exhibit adhesion issues, impacting the overall product quality.

2.Moisture Content:

Condensation: When capsules are subjected to fluctuating temperatures, especially if those temperatures are near the dew point, condensation may occur inside the capsules. For example, if a product stored in a cool environment is suddenly exposed to warmer conditions, moisture-laden air may condense within the capsule. This moisture can introduce a risk of chemical instability, microbial growth, or dissolution issues.

3.Chemical Stability:

Active Ingredient Degradation: Certain active ingredients are highly sensitive to temperature changes. For instance, proteins and peptides in pharmaceuticals may denature or degrade at elevated temperatures. Therefore, maintaining a controlled temperature environment during storage is critical to preserving the chemical stability of these ingredients within the hard capsule.

4.Capsule Dimensions:

Expansion and Contraction: Hard capsules may expand or contract with temperature variations. This phenomenon is particularly evident in the manufacturing process. For example, if capsules are filled at a higher temperature and then cooled, they may contract, affecting the final dosage form. This contraction can be critical in instances where precise dosing is essential.

5.Seal Integrity:

Seal Compromise: Capsules with separate bodies and caps that are sealed together may be vulnerable to temperature-related seal issues. For instance, if a capsule is filled at a higher temperature and then exposed to a rapid cooling process, the materials may contract at different rates, potentially compromising the seal integrity and leading to leakage or contamination.

6.Storage Conditions:

Recommended Storage Conditions: Manufacturers often specify temperature and humidity ranges for optimal storage conditions. For example, a pharmaceutical product enclosed in a hard capsule might require storage below a certain temperature to prevent degradation. Deviating from these recommendations could result in a reduction of the product's shelf life and efficacy.

To mitigate the effects of temperature fluctuations, manufacturers need to consider the specific characteristics of their products and capsules. This includes selecting appropriate materials, designing robust manufacturing processes, and implementing stringent quality control measures throughout the product lifecycle. Regular monitoring and testing are essential to ensure that hard capsules maintain their stability and deliver the intended therapeutic or nutritional benefits.

Enteric-coated HPMC Hollow Capsules