Whether you're shopping at a conventional grocery store like Kroger or a budget retailer, you're probably looking for value — good quality at a good price, says John Karolefski, grocery store analyst and editor of Grocery Stories. And if you regularly shop at Aldi, you know the grocery chain often delivers.
"Aldi, happily, has a lot of good quality , good-tasting products at good prices," Karolefski tells CNBC Make It. "It's one of the reasons they've been so successful in the U.S."
Part of the secret to the store's low prices is that the vast majority of their products are private label, so you're not paying for the marketing and advertising that many brands need to spend to attract customers. It's a strategy similar to the one used by fan favorite Trader Joe's, and it's worth noting that Aldi U.S. and Trader Joe's are independently operated companies with distinct but once-related corporate parents. It could be said that Aldi and Trader Joe's are "estranged cousins. "
Overall, Aldi has "got a good formula," Karolefski says. But of course some products are a better value than others.
Based on a mix of recommendations from Karolefski and our in-house analysis, here are five items you should always buy at Aldi.
Aldi's "SimplyNature" brand offers shoppers great value on organic products. Elsewhere, those "can be pricey, but you can get them for a good value at Aldi," Karolefski says.
In addition to being organic, frugal shopping expert LaurenGreutman reports that the SimplyNature products do not contain over 125 ingredients that experts have deemed questionable, including artificial flavors, high fructose corn syrup, trans fatty acids, nitrates and propylene glycol.
And still, many products cost substantially less than similar products sold under the Whole Food's "365 Everyday Value" label. For example, SimplyNature organic oatmeal pancake mix is $1.99, compared to the 365-brand organic pancake and waffle mix that goes for $3.99, according to local prices analyzed by CNBC using Basket, a grocery price comparison app.
Aldi's wines have received a lot of attention over the years, as they are arguably one of the best values around. Last year, Aldi's One Road Shiraz ($7) beat out a bottle that retails for $267 during the Great Australian Shiraz Challenge.
Aldi also took home an award for its Broken Clouds Chardonnay Sonoma Coast 2016 at the Private Label Manufacturers Association's 2018 International "Salute to Excellence Awards."
Overall, Aldi's site lists over a dozen wines that have won awards over the years.
Aldi's Specially Selected line of cheeses are hard to beat. For example, for only $2.79, you get 10 oz of the Specially Selected Aged Reserve White Cheddar, which won a gold medal at the 2013 United States Cheese Championship. An 8 oz block of the popular Cabot Vermont sharp cheddar cheese is $5.99 at a conventional grocery store like ShopRite, according to Basket.
The Specially Selected line also includes Gruyère and several soft cheeses.
Even more common options like string cheese for kids' lunches can be had for less. For example, a 12-pack of Sargento reduced-fat mozzarella string cheese is $3.94 at Walmart, while a Aldi's Happy Cows brand cheese is $2.79.
When it comes to meat, Karolefski recommends checking out the weekly ads and a promotional flier called Aldi Finds, where the store lists all the items on special sale. More expensive meats such as beef, salmon and turkey are typically featured at bargain prices.
For example, next week Aldi is offering a 10.6 oz pack of cold-smoked salmon for $10.99. The weekly ad also promotes a fresh, USDA Choice hand-trimmed beef tenderloin roast for $9.99 per pound.
If you're looking to pick up necessities like bread, milk and eggs, Aldi offers inexpensive and often high quality options. In a recent shopping experiment, we found that the price of bread at Aldi was 34 percent cheaper than at a conventional grocery chain like Acme. When it came to milk, Acme charged $2.99 for a half-gallon of regular whole milk, while Aldi's milk was just $2.69 — and it was organic.
"They have good prices across the board, but for the household staples like milk, eggs, bread — those are consistently lower priced," Karolefski says.
Don't miss: 6 foods you should never buy at Whole Foods
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