Persimmons Cold Storage
Cold Storage Conditions for Persimmons
Temperature and Humidity
Proper storage of persimmons in cold storage requires precise control of temperature and humidity to prevent spoilage, quality loss, and undesirable changes in the fruit. Persimmons are sensitive to temperature and humidity, and improper storage can quickly lead to softening, mold growth, and color changes.
Persimmons should be stored at temperatures between 0 to 2 degrees Celsius. This temperature helps keep persimmons in optimal condition and prevents rapid spoilage. Within this temperature range, microbial and enzymatic activities that can cause fruit spoilage are minimized. However, storing persimmons at temperatures below 0 degrees Celsius can cause freezing and damage to the fruit's tissue.
Stable temperatures are crucial in persimmon cold storage. The cold room should maintain a stable temperature without large fluctuations to prevent stress on the fruit. Temperature changes can cause stress in persimmons, reducing their quality. Fluctuations may cause the skin to crack, the tissue to soften, and increase the ripening rate.
Relative humidity, like temperature, is a vital factor for proper persimmon storage in cold storage. Maintaining appropriate relative humidity helps keep the fruit fresh, maintaining its texture and quality for a longer time. Inadequate or excessive humidity can have adverse effects on persimmons.
Maintaining a relative humidity level between 90% to 95% is essential to prevent drying and maintain the fruit's firmness. This humidity level helps keep persimmons in optimal storage conditions and prevents undesirable changes in texture and weight.
High humidity helps prevent water evaporation from the fruit's surface. If relative humidity is low, persimmons lose water, becoming wrinkled and losing weight. Therefore, excessive water evaporation should be prevented. Adequate humidity also helps maintain the firm and fresh texture of persimmons, preventing early softening. Consequently, high humidity storage increases the shelf life of persimmons and maintains their quality for longer periods. Thus, the cold room should be equipped with humidifiers and dehumidifiers to keep the humidity level consistently within the desired range. These devices play a crucial role in regulating and maintaining ideal humidity conditions.
Low humidity causes water to evaporate from the fruit's surface, leading to drying and wrinkling of persimmons, resulting in weight loss and reduced commercial value. Conversely, very high humidity can lead to mold and other fungal growth on the fruit's surface, causing spoilage and reduced persimmon quality. Additionally, high humidity increases microbial activity, accelerating fruit spoilage.
Ventilation and Ethylene Control in Persimmon Cold Storage
Proper ventilation in persimmon cold storage is crucial to maintaining the quality and freshness of the fruit. Ventilation not only helps distribute temperature and humidity evenly but also helps remove harmful gases like ethylene, preventing early spoilage of persimmons.
Even Distribution of Temperature and Humidity
Ventilation systems help distribute air evenly throughout the cold storage, ensuring consistent temperature and humidity everywhere. This prevents cold or warm spots in the storage room and creates optimal conditions for persimmon storage.
Prevention of Harmful Gas Accumulation
Proper ventilation helps remove harmful gases like ethylene produced by persimmons. Ethylene accumulation can accelerate the fruit's ripening process, causing early spoilage.
Ethylene Management in Persimmon Cold Storage
Ethylene is a natural gas produced by fruits during ripening. Ethylene accumulation in cold storage can accelerate ripening and spoilage of the fruits. Proper ethylene management is essential to maintain persimmon quality and prevent early spoilage. Methods of ethylene management include:
Ethylene Absorbers
Using ethylene absorbers that can absorb and neutralize this gas can help reduce ethylene levels in cold storage. These absorbers are usually installed as filters in the ventilation system.
Proper Ventilation
Proper and continuous ventilation can help remove ethylene from cold storage. By regulating air flow and continuously removing harmful gases, the ethylene level can be kept at an optimal level.
Use of Chemical Absorbents
Some chemical substances, like potassium permanganate, can help absorb ethylene. These substances are usually placed in small packets in the cold storage.
Temperature Control
Storing persimmons at lower temperatures can reduce ethylene production. Lower temperatures slow down metabolic processes, reducing ethylene production.
Main Differences of Persimmon Storage Compared to Other Fruits
Persimmon storage in cold storage has distinct differences compared to other fruits, stemming from its physiological characteristics and specific storage requirements. Due to its soft and sensitive structure, persimmons require more care than other fruits. The skin of persimmons is easily damaged, and if scratched or bruised, it becomes prone to spoilage. Therefore, the packaging and transportation of persimmons should be done with greater care.
Persimmons are sensitive to temperatures below 0 degrees Celsius and may suffer from cold damage, while many other fruits can be stored well at lower temperatures. Thus, precise temperature control in cold storage is particularly important for persimmons. Persimmons require high relative humidity (about 90 to 95%) to prevent drying and wilting. While other fruits may need different humidity levels, high humidity is crucial for persimmons to maintain their quality and freshness.
Persimmon Storage Requirements in Cold Storage
Packaging Method
Using suitable and sanitary packaging can extend the shelf life of persimmons. Secure and appropriate packaging can prevent contamination and air penetration, maintaining persimmon quality.
Harvesting Methods
Persimmons harvested using sanitary and appropriate methods can be stored longer in cold storage.
Pre-Storage Handling
To preserve freshness, persimmons should be transferred to cold storage and from storage to consumption as quickly as possible. The shorter the optimal storage time, the better the quality preservation.
Generally, persimmons can be stored for up to 3 to 4 weeks in cold storage at appropriate temperatures with suitable packaging. However, to maintain the best quality and longest storage duration, it is recommended to transfer persimmons from harvesting to cold storage and from storage to consumption as quickly as possible.
When is Subzero Cold Storage Used for Persimmons?
Subzero cold storage for persimmons is typically used in two conditions:
Long-Term Storage
When there is a need to store persimmons for a long period, such as international transportation or long-term storage for markets requiring frozen persimmons. In this case, persimmons are stored at subzero temperatures to prevent spoilage and biological changes from chemical and biological processes. This type of storage allows persimmons to maintain their freshness and quality for longer periods.
Special Conditions
In some special cases, there may be a need to store persimmons under specific conditions. For example, for special dietary programs or producing processed products that require preserving persimmons' freshness and quality over a long period, subzero cold storage can be used. In these cases, storing persimmons at lower temperatures can prevent bacterial growth, fermentation, and other spoilage processes, making persimmons suitable for use in high-quality food processing.
Hygiene and Disinfection of Cold Storage for Persimmon Protection
The disinfection process of persimmon cold storage is vital for maintaining hygiene and reducing food spoilage. This process includes several main steps. First, cold storage surfaces are periodically cleaned with detergents to remove various contaminants. Then, the surfaces are sprayed with specific disinfectants to kill potential microbes and bacteria. Additionally, all equipment used in cold storage must be disinfected. Using air ventilation systems with proper filtration can also help keep the air inside the cold storage clean, eliminating contaminated and bacteria-laden air. These processes should be continuously and periodically performed, with regular monitoring to ensure cold storage hygiene and maintain the stored products optimally.
Importance of Packaging in Persimmon Storage
Packaging persimmons in cold storage plays a crucial role in maintaining the quality and health of this product and should be done to prevent contamination, air penetration, and contact with contaminated surfaces. Proper packaging should be hygienic, using durable and impermeable boxes and bags to prevent contamination. These packages should be secure to prevent air and environmental contamination, maintaining persimmon quality.
Preserving persimmons' freshness is also crucial; packaging should prevent quality and freshness loss, achievable with non-permeable boxes and bags and storing in cold rooms at appropriate temperatures.
Labeling packages is also essential, as it shows important information like production date, expiration date, and storage conditions, helping consumers and cold storage managers maintain optimal storage conditions for persimmons. Moreover, packaging should be designed to transport persimmons to and from cold storage without damaging the product's quality. These packages should be durable and secure to prevent scratches and damage to persimmons during transportation, preserving their quality.
