The shelf life of cottage foods

Have you ever wondered how grocery stores determine the “use by” or “sell by” dates on food packages? These dates are based on how long the food maintains its best quality.

Here’s what those labels really mean:

Understanding packaging dates

• Sell By: This is the date by which the store should sell the product. It doesn’t mean the food is unsafe after that date. These dates are determined by inventory needs and potential quality deterioration in food.
• Best By: Indicates the date that the product will be at its peak flavor and quality. This is about taste and texture, not safety.
• Use By: This date is used to communicate to the consumer. This is the last date recommended for using the product while it’s still at peak quality. After this point, quality may noticeably decline. This date does not determine food safety. Exception: do not use infant formula or baby food past the “use by” date.

Food safety vs. quality

Although food safety and quality are related, they are not the same:

• Food safety refers to how food may affect someone’s health due to contamination from physical (e.g., hair, metal), chemical (e.g., cleaning agents), or biological (e.g., harmful bacteria) sources.
• Food quality encompasses taste, texture, appearance, and overall appeal. 

Spoilage occurs when microorganisms change the smell, taste, or appearance of food. While not all microorganisms that cause spoilage are harmful, some can lead to serious illness. For example, Clostridium botulinum can cause both food spoilage and botulism if ingested.

Shelf life and the Cottage Food Law

Under the Cottage Food Law, you are not required to determine the shelf life of your products. However, understanding shelf life helps answer customer questions and manage your own inventory effectively.

What impacts food quality?

The following environmental factors can impact food quality over time.

Sunlight and oxygen

Exposure to light and air can lead to chemical reactions that degrade food. These elements can cause fats to become rancid and alter the food’s color, smell and taste.

Moisture

Moist environments are ideal for the growth of bacteria and mold. Even sealed packaging can allow moisture to penetrate over time, increasing the risk of spoilage and stale texture.

Packaging

Proper packaging acts as a crucial barrier between food and the external environment. Using clean, food-grade, and appropriately designed packaging helps protect against contamination and limits exposure to sunlight, oxygen, and moisture. This plays a key role in preventing spoilage and the growth of harmful microorganisms.

Heat

Elevated temperatures can accelerate spoilage, promote bacterial growth, and degrade food quality. Storing food at the correct temperature is essential to preserving freshness and safety.

Shelf life by food type

Baked goods

• Shelf life: 2–3 weeks
• Signs of spoilage: Mold growth, texture or color changes, and off-flavors. 
• Tips: Store in an airtight container to maintain freshness.

Dried produce (fruits and vegetables)

• Shelf life: 6–12 months
• Signs of spoilage: Mold growth, texture or color changes, and off-flavors.
• Tips: Use airtight, moisture-proof packaging—for example, foil-lined bags with zip tops. Freeze-dried foods are especially moisture-sensitive; add food-safe moisture-absorbing packets for extra protection.

Canned foods

• Shelf life: Up to 12 months
• Signs of spoilage: Bulging (rounded) lids, leaking seals or mold. This may be a sign of Clostridium botulinum growth. Do not consume and dispose of it immediately. 
• Tips: Always use new, undamaged lids and follow tested canning procedures. Rings may be reused as long as they are in good condition and undented. A proper airtight seal is essential for both safety and shelf life.

Additional tips to extend shelf life

• Storage: Keep foods in a cool, dark, and dry place. Avoid excessive heat or humidity, as this can speed up spoilage and microbial growth.
• Sunlight: Exposure can cause fats and oils to go rancid, resulting in an off-flavor.
• Cleanliness: Always prepare and package food in a sanitized environment. Good hygiene and cleanliness help prevent contamination and prolong freshness.

Helpful resources

Food product shelf-life guide — Agriculture Utilization Resource Institute

Food storage guide — North Dakota State University