Spices are some of the most expensive items in your pantry, but they don't last forever.

There are several different "rules of thumb" for how long spices last ranging from six months to four years, making it tricky to know what guidelines to follow, reports the Daily Mail.

While spices don't actually spoil or go bad, they lose their flavor over time and can completely change the way a dish tastes - usually not in a good way.

We asked food experts for tips on when to clean out your spice cabinet and how to get the most out of your stash.

Advertisement

1. Go through your spice cabinet once a year

According to Frank Proto, a chef instructor at the Institute of Culinary Education, expired spices wont hurt you, "they just won't taste as good".

He outlined out the typical shelf-life for each of the four main categories of spices:

Ground spices - up to one year
Dried leaves and flowers - one year
Whole spices - one to two years
Whole seeds and roots - from two to three years
Going through your spice collection once a year is often enough to make sure everything is still good to use.

2. Check freshness with the sniff test

Most containers have a best by date, but that date isn't always reliable.

Rob Patterson, head of business development at Spices Inc, recommends using the sniff test instead.

"The easiest way to tell if your spices need to be replaced is if they've lost their aroma," he said.

"When you buy a new bag of ground cumin, for example, take a big whiff of that smell and try to remember it. Then in a few months when you go to use it again and aren't sure if it's still good shake the bag and then open it.

"If it doesn't have a big robust smell it likely won't have much flavor when you end up cooking with it."

3. Only buy what you can use in the prescribed period of time

Spices that are common recipe additions such as garlic, chili powder and cinnamon can be bought in larger quantities because they're likely to be used before expiration becomes an issue.

Other more seasonal spices are best bought in smaller quantities so that they don't get wasted.

For example, spices for pumpkin pie are usually only brought out around the holidays - so they're best bought in smaller containers.

Proto says that he sometimes splits spice purchases with his friends so they're less likely to go to waste.

4. Buy spices whole and grind them yourself in a coffee maker

Not only are whole spices usually cheaper than ground ones, they last longer.

"If you want the absolute best quality spice you can get go ahead and get the whole [product] and grind it as necessary," Patterson said.

"This gives you both the freshest flavor and the best bang for your buck because you can usually purchase it in larger sizes knowing that you can keep it for longer.

"As soon as a spice is harvested or picked the freshness begins deteriorating, and as soon as it's ground that timeline is accelerated substantially."

That's because they have less surface area and thus have less exposure to the air which can leach out the oils and flavors.

Spice grinders can cost up to $75, but a simple coffee grinder will also do the trick for less.

5. Don't store spices near the stove

The biggest threats to a spice's shelf life are heat, sunlight and moisture.

"Most everybody wants their spices within close proximity to where they cook and usually that means above or near the stove," Patterson said.

"Having your spices so close to a heat source can shorten their shelf life considerably, same goes for leaving your spices in a place that gets a lot of direct sunlight."

He said that refrigerating and freezing spices is also not a good idea.

"When you do that you run the risk of trapping moisture in the bag or jar each time you open it and then put it back. This causes the spice to break down quicker than it should as well."

Instead, Patterson recommends storing spices in a cool, dry place such as the pantry.

He and Proto also both emphasized the importance of keeping spices in airtight containers.