Cooking With Combi Ovens
Basic understanding of heat transfer is key to any form of cooking.
To understand combi ovens, you must understand the very basics of what it means to cook food. Whether over an open fire, skillet or an oven, this one thing, heat transfer, always has to happen to cook food. When heated, by definition of to cook, you are transferring heat to the food which causes physical and chemical changes of color, texture, flavor and nutritional value. But one key aspect often overlooked is, in order to cook food, moisture is being removed. Moisture is in every food item, and when heated, varying degrees of moisture is lost. It has to go somewhere, so it escapes the food and enters the cooking environment.
Cooking methods are generally divided into two categories: dry heat cooking or moist heat cooking. To debunk the complexity of the combi and the impact of humidity related to cooking, let’s try and understand the core essentials at play—temperature and humidity.
We always detail the ingredients in the foods we are cooking, yet pay less attention to how temperature and humidity can change these ingredients. Often time our understanding of combi, or lack thereof, is why we fear this cooking method the most. We understand a combi starts with modes; convection, steam and combi, yet the core of all modes is temperature and humidity. Controlling temperature and humidity is the root of all cook modes often referred to as combi, steam, convection, finishing, retherm, proofing, and more.
Relative humidity is the amount of water vapor present in the air divided by the maximum amount the air could contain at the given temperature. Expressed as a percentage, the relative humidity is 100% if the air is saturated with water vapor, and 0% if no water vapor is present. Think about a 90° day during the summer with 0% humidity. It’s a very dry heat, and feels like 90°. Now, the next day it is 90° with 100% humidity. This day feels a lot hotter than 90°, maybe even 110-120°. This phenomenon explains the science behind why food cooks faster with humidity in the cooking environment, such as in a combi oven.
Baking, grilling, roasting, steaming (water in a gas state) and broiling are all types of dry heat cooking. Typically temperatures are set to 300°F or higher. It is this application of heat that browns the food product; facilitating the delicious aromas and flavors your consumers enjoy.
Boiling, stewing, braising, and poaching are examples of moist heat cooking. Whether you cook with water, stock, wine, or another liquid, a moist heat method must involve cooking in moisture.
In the past, a foodservice operator would use both a convection oven and a steamer. Not so, anymore. Enter combi ovens. With one piece of equipment, an operator may employ multiple cooking capabilities to deliver a varied menu.
Looking to bake fresh bread for tonight’s service? A combi oven will circulate the temperature and humidity required to produce bread that is uniform in color and flavorful on the inside. Planning to poach fish for tomorrow’s lunch special? A combi oven will inject the necessary temperature and humidity into the oven to preserve the delicate nature of the fish. Braising a beef roast for stew? The precise levels of temperature and humidity in a combi oven will achieve the braising – in less time.
It is this versatility which has led to the adoption of combi ovens across many foodservice operations in the United States and Europe. Versatility is not the sole benefit of combi ovens, however.
Combi ovens also:
- improve product consistency
- decrease cook times
- allow for less kitchen equipment, saving on equipment acquisition costs
In addition, a combi oven also reduces the footprint of your commercial kitchen by allowing you to replace your convection oven and steamer with one piece of equipment, saving valuable floor space.
This article was written on August 2, 2016 by David Sager
Buying the Right Refrigerator
Considerations for investing in your business
We know that food quality is a key to your business success, and your refrigerator plays a vital role in maintaining that quality. We also suspect that with the constant demands that customers, employees, vendors and management place on your time, you likely haven’t had much opportunity to consider just how important your refrigerator—the unsung workhorse of your kitchen—is to your overall operation. Consider this: Refrigerators (freezers and hot-food cabinets) help maintain your food’s freshness, reduce unnecessary food loss, and work hard to keep your customers safe.
They’re required to consistently keep their cool in often hot, humid conditions, and they must seamlessly support your kitchen’s workflow. The fact is, if things are going well, you probably don’t give your refrigerator a second thought. However, think about what happens when your refrigerator doesn’t perform as expected. First and foremost, your customers’ health could be at risk. There’s also the potential for experiencing a devastating financial loss on your food investment. And it’s impossible to lose sight of the havoc a downed refrigerator can cause on your prep lines.
With all of these considerations impacting your success, it’s essential to invest in the right refrigerator. In this paper, we’ll provide you with the key points to consider when you make that important purchasing decision.
Performance reliability: The right refrigerator keeps food cold all day, every day.
We see it all too often in the news: contamination scares stemming from the foods we least expect,
like produce. These headlines clearly illustrate that sometimes it’s the foods we don’t expect to cook
that become most hazardous, under less than ideal circumstances. In light of this reality, you must have complete confidence that your new refrigerator will maintain a safe holding temperature in the real-world conditions of your kitchen 24/7/365. No surprises; no exceptions.
Virtually all brands can hold the right temperature some of the time. The real trick is holding that temperature regardless of how often the door is opened, how hot your kitchen becomes or both. Here are
things to consider when evaluating a unit’s performance reliability:
Refrigerant Metering Devices
Refrigerant is your unit’s lifeblood. The refrigerant metering device maintains the proper flow of refrigerant throughout the cooling system. The device causes your refrigerant pressure to drop, which, in turn, decreases the temperature. The resulting change in pressure and temperature allows heat to be absorbed during the refrigeration cycle.
There are two common refrigerant metering devices: thermal expansion valves (TXV) and capillary tubes. Using a sensing bulb that drives refrigerant response, a TXV immediately reacts to increased demand—such as door openings—by releasing more refrigerant into the system. This responsiveness (known as “recovery”) improves the system’s ability to quickly cool the cabinet. Faster cooling promotes food safety and maximizes a food’s shelf life.
Separately, capillary tubes are thin pipes made of copper. They allow a measured amount of refrigerant
into the evaporator coil. They do not respond to demand. That is, they provide the exact same amount
of refrigerant regardless of whether the door is open or closed. Because of this design, they are unable to experience rapid temperature recovery. Without rapid temperature recovery, they can contribute to increased food temperatures. Higher temperature ultimately leads to reduced shelf life and increased food cost.
To emphasize the impact of increased food cost due to improper refrigeration, consider what happens to milk at varying temperatures. A global leader in refrigeration science indicates that milk held below 41 degrees Fahrenheit will last up to seven days. However, at 45 degrees Fahrenheit, milk remains safe for only three days. In terms of dollars and cents, $25 of recurring weekly food loss due to improper refrigeration works out to $1,300 over the course of a year. Of course, that number increases dramatically if even more than that dollar amount of food spoils prematurely each week. Also keep in mind that food quality strongly impacts the customer experience. That means customer satisfaction and, ultimately, repeat business can also be adversely affected by poor storage temperatures.
Read the entire white paper.
Hobart “Glass Washers”
Hobart “Glass Washers” help provide better drinks, reduce operating costs and saves labor with no more hand washing required. With Advansys LXGe glass washers, serving your drinks in clean, sparkling glassware has never been easier — or more energy efficient. Every feature is designed to help you save time and money, with superior cleaning performance eliminating chemical residue so the full flavor and enjoyment of your beverages always shine through.
STANDARD FEATURES INCLUDE:
InSinkErator’s PowerRinse Waste Collection System improves kitchen efficiency by increasing pre-rinse and scrapping speed, while reducing bulk waste without griding. With PowerRinse, operators can now double or even triple their speed. PowerRinse utilizes 50 percent less fresh water per hour than competitive units–only 1 Gallon Per Minute! Scrapping and pri-rinsing can be accomplished in just one step prior to dishwasher. Solid waste is sent down the drain. An alternative to food waste disposers or pulper systems, PowerRinse is easy to service, maintain, and install. Each unit is pre-plumbed a pre-wired, with a direct connection to hot and cold water, electricity, and drains. The system can be hosed down and components are dishwasher safe.