Canned and packaged foods are among the most tightly regulated products in the world. Every container that reaches store shelves carries essential information—batch codes, lot numbers, expiration dates, and sometimes branding—that ensures food safety and compliance with regulations. In our experience, the canning industry depends on permanent, reliable markings to safeguard consumers and protect manufacturers from risk. One of the most practical ways to achieve this permanence is through custom hand stamps, which provide durable identifiers that last throughout production, distribution, and storage.
This article builds on our earlier discussion of traceability with serial number stamping by expanding on the specific markings required in the canning and food packaging sectors—and by taking a closer look at the history and importance of expiration dates.
Types of Markings Required in Food Packaging
Markings on food packaging serve multiple purposes. They satisfy regulatory requirements, enable traceability, and provide consumers with vital information. In our experience, the most common markings include:
Lot Codes
Lot codes identify a group of products manufactured under the same conditions, often within a single production run. If a defect or contamination is discovered, lot codes allow companies to quickly identify and isolate affected products. Without them, recalls can become overly broad, resulting in unnecessary waste and damage to brand reputation.
Batch Numbers
Batch numbers are similar to lot codes but often carry more detailed information, including the exact date and shift of production. In large-scale canning operations, batch numbers are critical for linking products back to specific machines, operators, or ingredient sources. In our experience, stamping batch numbers directly onto cans or packaging provides an indelible record that supports both quality assurance and regulatory compliance.
Expiration Dates
Expiration dates—or “best by” and “use by” dates—are the markings most visible to consumers. These dates provide assurance that the food remains safe and of acceptable quality until a certain time. Unlike lot codes, which are primarily for manufacturers and regulators, expiration dates communicate directly with customers. Because of this visibility, they must be applied in a clear, legible, and permanent way. A smudged or missing date not only raises compliance issues but also undermines consumer trust.
Compliance Labels and Symbols
In some regions, cans and food packaging must carry additional compliance identifiers, such as FDA or USDA inspection marks. These demonstrate that the product has passed required safety checks. Permanent engraving ensures that these symbols remain intact throughout the product’s lifecycle, even when exposed to moisture, sterilization, and handling.
Branding and Logos
While not strictly required, many food manufacturers engrave or emboss branding onto packaging. This reinforces authenticity, discourages counterfeiting, and builds customer loyalty. In our experience, custom engraving allows companies to merge compliance with marketing by combining identifiers like lot codes with distinctive brand marks.
The History of Expiration Dates
The concept of expiration dates is relatively modern in food history. For centuries, preservation methods like salting, smoking, or canning were trusted without official labeling. However, as food production industrialized in the 19th and 20th centuries, consumer demand for transparency grew.
Early 20th Century Developments
Expiration labeling began gaining traction in the early 1900s when packaged foods became widespread. Manufacturers wanted a way to reassure consumers about freshness and safety. In our experience, early marks were often codes intended for internal use rather than clear dates for customers.
The Rise of “Sell By” and “Use By” Labels
By the 1970s, consumer advocacy groups pushed for clearer labeling. Retailers began using “sell by” dates to manage stock rotation, while manufacturers added “use by” and “best before” dates to guide consumer use. This shift represented a major step in consumer rights, as customers now had direct insight into product shelf life.
Regulatory Standardization
In the decades since, expiration dates have become regulated by national food safety authorities. Today, nearly all packaged foods, especially canned goods, must carry expiration information. This labeling not only prevents spoiled food from reaching consumers but also streamlines recalls by linking products to specific timeframes.
How Permanent Marking Supports Expiration Dates
Expiration dates are only effective if they remain visible throughout the product’s journey. Inkjet codes and labels can fade, peel, or smear during sterilization, transportation, and storage. In our experience, custom hand stamps create impressions that remain clear even after years in a pantry or warehouse. This permanence ensures that consumers, regulators, and retailers can always read critical information.
Traceability Benefits Beyond Expiration Dates
Expiration dates are just one part of the bigger picture of traceability. When combined with lot codes and batch numbers, they form a complete system that allows manufacturers to track every product from raw materials to consumption. In our experience, permanent engraving supports this system by providing an unbroken chain of information that cannot be lost to fading ink or missing labels.
Examples of Markings in Practice
Different food categories use expiration and lot markings in slightly different ways:
- Canned vegetables and meats: Typically stamped with batch codes and expiration dates that survive sterilization processes.
- Beverages: Often require clear “best by” dates for consumer confidence and regulatory compliance.
- Baby food: Marked with precise expiration dates due to heightened safety requirements.
- Ready-to-eat meals: Carry lot codes for traceability and expiration dates for both consumers and regulators.
Best Practices for Applying Markings in Canning
Based on our experience, successful marking in the canning industry follows a few best practices:
- Apply permanent marks early in the production process to avoid errors or omissions.
- Ensure that expiration dates are clearly legible to consumers.
- Combine compliance symbols with lot codes to streamline audits and inspections.
- Train operators to use stamping tools consistently to maintain uniform markings.
Final Thoughts: Markings as a Pillar of Food Safety
Markings on cans and food packaging are far more than regulatory details—they are a direct link between manufacturers and consumers. Lot codes and batch numbers safeguard traceability, while expiration dates reassure customers that the product is safe and fresh. In our experience, custom hand stamps provide a reliable way to make these markings permanent, legible, and compliant across the food supply chain. For an industry built on consumer trust, there is no substitute for clarity and permanence in packaging identifiers.