From the primitive ice buckets of yesteryear to the modern day refrigerator, the technology we use to keep our food cool has evolved. Yet, even though the methods have changed over the years, the basic principles of cooling have been the same for centuries and we have always used a cooling substance and some form of insulation.

Whereas early systems might have used ice as the cooling substance, today we use chemical refrigerants. Refrigerants work by moving through the refrigeration cycle changing from gas to liquid and back again. Early refrigerants posed risks but the R-134a and R-600a refrigerants used today are non-corrosive, non-toxic, low cost, and environmentally friendly.

Insulation is another important element of a fridge as it keeps the warm air outside from penetrating the cool atmosphere of the fridge. In times past, the insulation was simply the ice bucket itself, or the stone wall of an archaic ice house. Now, a more sophisticated type of insulation is used whereby a urethane foam and VIP (Vacuum Insulation Panel) maintain the temperature of a refrigerator.

At its most basic, a refrigerator consists of four main parts that together work their magic to produce refrigeration.

Refrigerant in the form of liquid or gas circulates in the refrigeration cycle successively for cooling action

• Compressor: The compressor circulates the refrigerant by converting it between a low-temperature, low-pressure gas to a high-temperature, high pressure gas

• Condenser: The condenser transforms the high-temperature, high-pressure gas to a room-temperature high pressure liquid by discharging radiation heat

• Capillary tube: The capillary tube drops refrigerant’s pressure for next cooling action by passing it through a narrow tube with high resistance – the room-temperature, high-pressure liquid becomes a low-pressure, low-temperature two-phase fluid

• Evaporator: The refrigerant which is decompressed by the capillary tube evaporates at low temperature when entering the evaporator. The evaporator cools the fridge and freezer by absorbing heat from the food, which turns liquid into gas

New Wave of Fridge Tech: Twin Cooling Plus^TM

Samsung is reinventing the fridge by developing Twin Cooling Plus^TM technology, first introduced in 1995. The Samsung Twin Cooling Plus^TM adds new levels of convenience and innovation with its two evaporators that manage the fridge and freezer space separately to minimize temperature fluctuation. This makes it possible to control optimal humidity and temperature because moisture in the fridge can remain separate from freezer. A higher humidity up to 70% preserves food for longer so this is a welcome addition that minimizes food wastage.

Additionally, in conventional – single evaporator – systems, odors from the fridge can be permeated to foods in the freezer because air from the two compartments is interconnected. Twin Cooling Plus^TM fridges, however, prevent mixed odors that taint the ice you store in the freezer because twin cooling systems prevent air transition between the two compartments.

The comparison between mono cooling with single evaporator (left) and Twin Cooling Plus TM with two evaporators (right)

Fridge flexibility is another bonus that users can make use of with Twin Cooling Plus^TM . It offers a range of options that enable users to customize their fridge in a way that best suits them. They can even switch off portions of their fridges to save energy. This is done through the separate cooling evaporators for the fridge and freezer that enables users to choose from five modes of operation: regular mode, energy saving mode, vacation mode, fridge max mode, and mini fridge mode.

A Growing Range

With Twin Cooling Plus^TM technology now an established feature in Samsung fridges, the range of available products has grown to accommodate the different consumer needs. There’s the side by side refrigerators, the bottom mount fridges and top mount fridges – all with their unique benefits and features.

Then there’s the T-type refrigerator – a world first Samsung. It’s the only Triple Cooling and dual compressor fridge in the world. Each zone can be controlled independently and maintain optimal high humidity levels.

The fridge has come a long way from the early days of inefficient appliance with limited capabilities. Samsung is now at the forefront of rethinking the fridge. As a result, it will get more efficient, offer better insulation, more space and it will get smarter. The fridge no longer needs to be forgotten about – it can be embraced and interacted with in new ways.

It’s a dilemma that has two options. One choice is to buy fewer items in the weekly shop and then make more trips to the local store throughout the week. But that’s inefficient, and ends up costing more in the long run. The other option is to buy a bigger fridge. The only problem there is the space in the kitchen limits your ability to buy bigger white goods.

The solution that makes the most sense is to opt for a bigger fridge that has the same footprint as your old one. Impossible? No, this is actually an issue refrigerator engineers have been tackling for quite some time.

Samsung SpaceMax Technology

SpaceMax technology is the sum of solutions Samsung engineers have found. One way Samsung works to offer more capacity than the average fridge is by being smarter with the insulation. The insulation in SpaceMax fridges is thinner but efficient.

The technology first made an appearance in Samsung’s 2008 refrigerators developed under project name Guggenheim. The application of thinner insulation helped increase the capacity by an additional 100 litres. Proving its impact on the market, this model is still on sale eight years on.

To get the correct formula for success, it requires an incredible feat in optimization. There’s a need to consider both capacity and energy. For instance, you cannot only make the wall thinner for expanded capacity. Similarly, you can’t just make the walls thicker to achieve better energy efficiency. You have to consider both factors rationally.

SpaceMax works through high efficiency poly-urethane (PU) foam insulation and Vacuum Insulation Panels (VIP) working in tandem to increase capacity without compromising on insulation. The results are clear. The freezer wall has gone from 60mm to 55mm, and the fridge wall 45mm to 30mm. The freezer door and fridge door have both slimmed down by 20~25mm and 5~10mm respectively.

Poly-Urethane Foam Insulation with Smaller Cells

Let’s take a closer look at the high efficiency foaming technology used in the insulation. Urethane is a well-known material that fills up the inner wall of the fridge. It’s used in both commercial and general fridges. With an innovative advancement in creating a poly-urethane layer, Samsung was able to decrease the cell size from 200-300㎛ to 100-150㎛. This helped reduce thermal conductivity, which in result improves insulation efficiency by 6.5%.

Vacuum, Arguably the Best Solution for Insulation

While the PU foam layer became better at cutting of heat radiation, Samsung wanted to do more. That’s where the vacuum insulation panel comes in.

A vacuum state, by definition, eliminates matters that conduct heat. (That’s why many thermal bottles have a vacuum layer.) While it would be structurally and economically challenging to build a whole refrigerator wall that is in a vacuum state, Samsung engineers still found a way to add vacuum panels to cut off heat conduction. If you were to dismantle your Samsung refrigerator wall, you would find the panels on the outermost layer of the insulation – right under the surface material, inwardly sealed off by the PU foam.

Although the exact numbers vary between different models, the rule of thumb is that if the thickness of insulation decreases by 1mm, the capacity increases by 10 liters. Continued breakthroughs have meant that average capacity of our fridges has grown over the years. In the 1990s, capacity sat between 200 and 300 liters. By 2014, that figure was 980 liters.  Every millimeter counts in the challenge to increase fridge space. And if it means your groceries can slide in with ease, the SpaceMax innovation is worthwhile.

Temperature

Though many are not aware that certain foods must be maintained at certain temperatures and humidity levels, these two factors play a vital role in optimizing the freshness of food. For starters, bacteria starts tripling at 40 degrees Fahrenheit (4 degrees Celsius), and freezes at 32 degrees Fahrenheit (zero degrees Celsius) so keep the temperature at an optimal 37 degrees Fahrenheit to slow the growth of bacteria. Be sure to occasionally check the internal temperature to ensure your appliance is working properly.

Ensuring that this temperature is steady is also of great importance. Improved technological advancements in refrigeration, such as Samsung’s innovative Triple Metal Cooling steel panels, ensure a steady temperature and have greatly improved food freshness. For specific cooking and serving needs, like chilling drinks before a party or marinating meat, utilize temperature-controlled compartments.

Furthermore, you should minimize the number of times you open the fridge door, check to ensure that the door is sealed and let cooked foods cool down before putting them away to ensure constant and consistent cooling.

It should also be noted that certain food items require specific temperatures. Dairy products, for example, spoil easily and as such should be placed in the coolest part of the refrigerator — near the bottom, in the back — while products with more preservatives, like condiments and orange juice, are okay on the door, where temperatures tend to fluctuate. Avoid cramming too much into your fridge and place items in a way so that air can properly circulate between them to create a uniform temperature with fewer warm spots. Take note of foods that don’t need to be refrigerated, such as potatoes, tomatoes, onions and honey, to conserve space.

Humidity

Humidity levels can also impact the freshness of food. The general rule of thumb is that foods that wilt (like arugula, spinach and herbs) should be placed in a high humidity environment, while foods that rot (i.e. fruits and vegetables that emit ethylene gas, such as apples and pears) should be placed in a low humidity setting.

Newer cold storage appliances are designed in a way to allow for optimized freshness through humidity controlling features. Take the Samsung Chef Collection refrigerator, for example. While the appliance’s Triple Cooling technology, which uses three evaporators and two compressors to control temperature and humidity, promotes an air quality that ensures great freshness, its Chef Basket and Chef Pantry maintain precise temperatures and humidity levels for specific foods.

Storage and Organization

This particular refrigerator was designed by the Samsung Club des Chefs, a group of culinary masters who provided valuable insight into the design and features of Samsung’s latest line of kitchen appliances. Advisor to the club and food critic Pierre-Yves Chupin notes that checking the condition of the food before putting it in the refrigerator is just as important as how it is stored.

For example, you should systematically remove the cardboard or plastic wrapping from your groceries. Fruit and vegetables should be washed before being putting away, as food that has been in direct contact with the soil should never be placed around other edible items. After washing them, you should keep salads in containers, with a layer of paper towel at the bottom and on top, to keep them fresh and crisp. Raw meats and seafood should be placed on the bottom shelf to prevent spills. If marinating or preparing the meat to cook, features such as the dishwasher-safe Chef Pan are great for temporary storage.

Leftovers can be stored for up to four days in clear glass containers and drawers and baskets should be labeled with contents regularly. Seeing what foods are left over helps you to eat them sooner, creating less food waste. Additionally, before every grocery trip, move older foods hiding in the back to the front to take inventory.

Cleaning

It is important to clean the inside of the refrigerator regularly by emptying it and washing the doors and shelves with a disinfectant such as diluted bleach. Do not spray substances directly on the surface; instead apply a small amount of cleaner on a rag and then wipe the surface. For stubborn stains, make a paste of baking soda and warm water, and apply it gently to the area with a warm soft cloth. For fingerprints and smudges, a few drops of olive oil applied with a paper towel can do wonders.

To take the hassle out of cleaning, wipe spills and messes when fresh and remove expired items to save space for fresh leftovers and foods you’ll want to eat. To keep unwanted smells at bay, try placing a saucer of coffee grinds or half a lemon inside the fridge.