David Lee holds on to his carts while shopping at a Costco Wholesale in Portland, Ore. (Rick Bowmer/AP)

Losing power during record-breaking temperatures was miserable at best and devastating at worst. Throwing out spoiled food only added to the agony, and people who buy food in bulk to save money were hit especially hard. Is it ever wise to stock up on groceries in these sweltering summer months?

“Common sense always needs to prevail when buying in bulk,” said Tod Marks, senior projects editor with Consumer Reports. “Perishables don’t keep as well in extreme heat or humid conditions. That means items that tend to spoil, as well as bread and cereals, can become soggy due to moisture and humidity.”

Although the heat burned us this month, that doesn’t mean we should stop stocking the kitchen. Marks tells us how to buy in bulk the smart way and how to save despite the tempestuous weather.

The summer bulk

Spoiler alert

Even if the electricity doesn’t go out for days, heat and humidity seep into homes. If you’re used to buying perishable items in bulk each week, take into account that these items will rot or expire faster in the summer than in the winter. “I’m reluctant to buy food in bulk during the summer, but dried goods, pastas, dried beans and canned goods are good things to buy in bulk,” Marks says. 


Buying flour or other food you plan to keep open in the kitchen? Marks warns of spoilers other than heat. “There are bugs in the summer that can penetrate open packages,” he says. 

Know your habits

The amount of food your household consumes varies with the seasons. Because of vacations, summer camps and increased outdoor activity, it’s possible that you’re drinking more and eating less. Stocking up on nonperishable liquids is recommended in the heat. Remember that hearty foods — breads, meats, cheeses, vegetables — may not be in demand.

Warehouse test

It’s still cheaper to buy in bulk

Consumer Reports conducted its supermarket ratings report by comparing four common shopping methods: the impulse shopper, the savvy shopper, the off-brand shopper and the warehouse clubber. By comparing the prices of the same grocery basket purchased in four ways, here’s what it found about shopping in bulk: 

Impulse shopper: $164

A basket of 30 items regardless of sale items and coupons cost more than $160.  

Savvy shopper: $93

The savvy shopper bought the same brand items in sizes on sale and saved about $70.

Store-brand customer: $66

Shopping off-brand, or replacing the 30 items with store-brand products rather than national brands, saved almost $100. 

Warehouse club: $68

Shoppers who bought the 30 brand items at warehouse stores saved almost $100 (after converting the purchase to units to compare weight).

Bottom line: Buying in bulk will save about 60 percent when you frequent warehouse clubs.

Expert tips

Institutional size vs. Multipack

Marks reminds us that shopping in bulk can be done two ways: buying institutional sizes of product (such as a six-pound can of tomatoes) or buying multipacks. If you’re buying food, it’s smartest to buy multipacks so most of the food remains sealed until you need it. 

Ignore the fee

Marks estimates that about 100 million people in the United States belong to some sort of warehouse club. That’s because they’re a good deal. “The fee is nominal,” Marks says. “You’re not just buying groceries. You’re buying services, prescription drugs, travel . . . and also clothing and electronics. You can pay off the cost of membership in one purchase.” 

Go in with a friend

For singles in the city who worry about spoilage, Marks suggests splitting bulk-food purchases with a neighbor or friend. Although buying in bulk makes sense for items such as aluminum foil, paper towels, dog food and tissues, storage space is a problem city dwellers must consider. Splitting these necessities between two shoppers is a great way to save space and money.


THE BOTTOM LINE: Buying in bulk tends to save money, but buying large quantities of food during the summer months, even without power outages, can lead to waste. It’s almost always cheaper to buy nonperishables from warehouse stores, but if you’re not feeding a family, avoid stocking up on stuff that spoils quickly.