Best Refrigerator Temperature to Keep Food Fresh

[MachineGhost]

Another mystery quantified!

For the food in your refrigerator to stay fresh for as long as possible—no ice crystals on the lettuce or bacteria breeding in warm spots—the refrigerator temperature should hover right around 37° F. In the freezer, a temperature of 0° F will keep foods thoroughly frozen.

Knowing that, the reasonable step would be to set your refrigerator to those temperatures. But the temperature controls on many refrigerators only allow you to choose from a series of numbers—say, from 1 to 5, with 1 being the coldest and 5 the warmest. Even when refrigerators have digital controls that allow you to set a specific refrigerator temperature, the settings aren’t always accurate. But the temperature-measuring equipment Consumer Reports uses in its tests is extremely precise, down to a fraction of a degree, so we can tell you exactly where to set your refrigerator temperature to achieve optimal freshness.

http://www.consumerreports.org/refriger ... ood-fresh/

[flyingpylon]

I bought a new refrigerator in 2014 that has a front digital display and it was set to 37 and 0 at the factory... I've never changed it and I guess now I know I don't have to. I haven't verified it either, but if I try to do that and it's not exactly right it will just be another problem to solve and ain't nobody got time for that!

[Maddy]

Speaking as someone whose livelihood for half the year revolves around commercial food production, I can say with some authority that the temperatures generally recommended for home refrigerators are way too high for optimal fresh food storage. Thirty-seven degrees F. may be adequate for food safety purposes, but the vast majority of fresh fruits and vegetables require temperatures in the area of 32-36 degrees. It's no coincidence that the term "cold storage" in commercial production refers to temperatures in a narrow range between 32 and 36 degrees F.

The rate of respiration in fruits and veggies is directly related to storage temperature, and it is the rate of respiration (together with the rate of growth of pathogenic fungi) that is the main factor determining the rate of decay. In some fast-respiring fruits (e.g., strawberries), it's been said that one hour at room temperature decreases the storage life by a full day.

Here are some examples of temperatures recommended by my state's ag service for various produce items:

Carrots: 32
Asparagus: 32-35
Broccoli: 32
Cabbage: 32
Apples: 30-40
Raspberries & strawberries: 32
Peaches: 31-32 (I happen to disagree with this one, but that's beside the point)

I'd suggest that the temperature settings recommended by government agencies (and imposed upon manufacturers) have more to do with politics than they do with optimal food storage practices.

[WiseOne]

Here are some examples of temperatures recommended by my state's ag service for various produce items:

Carrots: 32
Asparagus: 32-35
Broccoli: 32
Cabbage: 32
Apples: 30-40
Raspberries & strawberries: 32
Peaches: 31-32 (I happen to disagree with this one, but that's beside the point)

I'd suggest that the temperature settings recommended by government agencies (and imposed upon manufacturers) have more to do with politics than they do with optimal food storage practices.

Thanks Maddie!

I try to keep my fridge on lowest setting possible without freezing, but that's difficult as fridge temps are not that even. Stuff in the back freezes while temps in the front are in the mid 30s, and 40 degrees on the door shelves. That aside though....I don't understand the above temps. 32 degrees is the freezing point. I assume it means you need to keep them barely above freezing, but those numbers are just odd.

[Maddy]

Here's my understanding of it: 32 degrees F. is the freezing point of water, but it takes a slightly lower temperature for fruits and vegetables to freeze. For example, the freezing point for apples is 29.3 degrees F.; that of carrots is 29.5. Strawberries don't freeze until you get to 30.6.

Anecdotally, I find that there's a tension between what's optimal in terms of shelf life and what's optimal from the standpoint of quality. If produce is going to be consumed fairly quickly, its texture and appearance seem to me to be a whole lot better if it's kept closer to 40 degrees than 30. That's especially true with highly perishable fruits such as peaches and strawberries. But shelf life (longevity) definitely suffers as a result. The difference in quality is so apparent to me that when I harvest in the evening for delivery to the next day's farmer's market, I'll generally opt for storage in ice chests where the temperature is generally no lower than 50.

My observation that higher temperatures are better for maintaining produce quality over the short term run counter to everything I read in the articles coming out of the universities. I'd surmise that because those studies are geared toward large-scale commercial production, they're assuming fairly lengthy delays between harvest and consumption and that their idea of "quality" and mine are miles apart.

FWIW, it's my belief that the reason why you can't buy a decent peach in the grocery store is that the near-freezing temperatures that are required to keep them fresh during long-distance transport cause their innards to turn to mush.

[MachineGhost]

Then 37 it is?

[dragoncar]

I keep mine at 33. Sometimes get frost on vegetables but not a big deal. Still get mold on food when I'm not fast enough