There are primarily two types of soup classification: broth-based (think chicken noodle) or cream-based (think chowder). Tomato-based products can be classified as either; for example, minestrone would be a broth-based soup vs. a creamy tomato-basil. There are exceptions, such as thin purées of vegetable or legumes using water instead of broth, but these still may be considered broth-based, with the vegetable liquid matrix acting as would a meat or poultry broth.

Broth-based soups tend to be the most popular, and the method of producing soup broths can vary. In large-batch production, the use of soup bases became the most common method. But, the movement toward more natural products opened the door for companies that specialize in bases, making available multiple formats, from powdered to liquid to frozen; organic and “natural;” low-sodium and gluten-free; and custom bases. These are available in varying concentrations, as well.

Another option to bases is broths manufactured from residual byproducts of poultry, beef or other proteins. For example, a producer of IQF diced chicken will take the broth produced in the process, clarify it, then dilute it to a specified concentration.

Using these products often calls for the addition of other flavoring systems to boost their character. Such broths lack the salt and yeast that make up the strength of a concentrated base but give the flexibly to control the sodium levels and flavor of the finished product. In a concentrated broth system, the soup maker can add salt or salt substitutes to a desired level, then perhaps include a touch of a roasted flavor system and spices designed for a particular recipe or profile.

Of recent development are companies that make authentic stocks and demi-glaçes. However, for large-batch production, these can be expensive and are used mostly for retail or in restaurants.

Make it Chunky

Produce is one of the common soup components after broth. The tricky part about product inclusions is striking the right balance between particle size and batch volume. Fresh produce quality, including water content, varies widely—along with price—across and within any given season. Also, in-house processing of produce might not be optimal, due to additional equipment needs or labor costs.

To use fresh produce, a soup maker can connect with a local, Global Food Safety Initiative (GFSI)-certified  processor. Such certification is critical to any food operation, of course. But, when dealing with fresh produce sources, that certification might not always be in evidence.

A more common option is to use IQF produce. This option is best for overall price and consistency. Most frozen produce is processed and flash-frozen right in the field, preserving flavor, color and nutrients. This also avoids changes inflicted on produce through post-cut exposure to temperature variations, light and cross-contaminants. IQF produce products are most often contracted out to the buyer, so the farmer/packer knows what to grow, process and store for a client. This type of planned buying offers the best possible costing, although it does require advanced planning.

Spice it Up

Ethnic demands have helped make soup varieties more numerous than in the past. These are the soups that bring a touch of the global and exotic. Mexican posole, Thai tom kha kai or Vietnamese phô are in as much demand as the resurgent down-home comfort soups, such as chicken and dumpling, cream of mushroom, minestrone or beefy vegetable. Even the upscale and envelope-pushing soups, like roasted fennel and butternut squash or watercress and lemon, are entering the mainstream. All require authentic flavors for success in the marketplace.

Flavor systems come in many formats: dried, powdered, liquid, pastes, or oil- or water-based. Each challenges the formulator with different usage levels. There are systems for almost every flavor note, from herbs and spices, to protein flavors; roasted, grilled and fried flavors; and flavor systems for every dairy product imaginable. In fact, today’s flavor makers have developed such comprehensive portfolios that the flavor concept a developer has in mind is likely already available. And, if it isn’t, today’s flavor innovation centers are at the cutting edge of technical advancement, employing flavor biochemists and research chefs who can custom-build virtually any flavor concept from scratch.

Flavoring systems can be a valuable cost-reduction solution. Yet, employing pre-made flavors involves a balance between the desired flavor price one is trying to achieve and the flavor that will be. If used properly, one can achieve a cost reduction and an acceptable, very good product.

Even dried powders, now most common to ramen-type instant Asian soups, have become more sophisticated. No more are they little packets of mostly MSG and dehydrated onion. Instant soup companies have taken advantage of flavor technology to merge instant with homemade.

“Cooking miso soup from scratch usually requires lengthy simmering of its traditional ingredients to yield a rich soup stock,” says Joel Dee, founder and president of Edward & Sons Trading Co. “To make a soup the busy home cook can use to spare the cooking time and hassle of preparation but achieve authentic results, we developed specialized organic miso varieties.”

Dee explains that, by adjusting the ratio of organic rice and organic soybeans in its miso recipes, including using a higher percentage of organic rice koji (the natural Aspergillus oryzae fungus used to ferment rice or soybeans), they were able to “create a sweeter tasting soup.” He adds, “Also, extending miso aging time from three to six months allowed us to produces a stronger umami characteristics and a wonderful, full-bodied aroma. Blending select seaweed and mushroom extracts with the special organic miso completes the complex flavor notes of our instant Miso-Cup offerings to rival the miso soups served in high-end Japanese restaurants and sushi bars.”

Pre-flavored broths are also available, combining the liquid portion and the flavorant systems in a single format. Campbell Soup Co. North America’s Swanson brand introduced a line of “flavor-infused broths” available for retail and for some processors. The company describes the line as “inspired by global flavors designed to satisfy the ever-expanding American palate.” The broths are available in Mexican Tortilla, Thai Ginger and Chinese Hot & Sour varieties. Each is “made with ethnic spices to add bold and complex flavors to dishes without the hassle of hard-to-find ingredients.”

The Mexican Tortilla flavor is infused with the Monterey Jack cheese flavor, lime, cayenne pepper, cumin, toasted corn, jalapeño pepper and paprika. The Thai Ginger is infused with soy sauce, cilantro, lemongrass, ginger, coconut and lime. The Chinese Hot & Sour Flavor also has the flavors of soy sauce, supported with cayenne pepper, onion, garlic and ginger.

From Pasta to Protein

Pastas, grains and meats can be applied to soup formulations in endless varieties and combinations. For raw animal protein, a HACCP plan should be in place to cover handling, as well as in-house storage and processing. However, prepared meat products come in all formats: roasted, rotisserie, grilled, diced, shredded, strips or ground form—all suitable for soups, stews and chilies. Using pre- or custom-prepared meats can be a huge benefit, decreasing stress and improving ingredient and labor costs.

The same holds true for pastas and grains. The advantage to these products, as well, is that they can be made to match all needed profiles. They can also address the increased demand for ethnic products: A dozen years ago, grilled chipotlé chicken and hominy for a tortilla posole soup were difficult find. Today, these ingredients are readily available.

The grain movement is moving ahead quickly with solid marketability built on positive health perceptions. Most grains take time to cook, and cooking them perfectly, as well as consistently, can be challenging. Today, many grains and grain products are available fully cooked and ready to add to the kettles. Turning to pre-cooked grain product can make for better success.

Cooking pastas in-house has advantages but also comes with challenges. Boiling and straining 100lbs of raw pasta yields 200-300lbs cooked, which then needs to be chilled before it turns to mush. Then, it has to survive packaging, shipping and storing or, again, mush. Formulators of late have been turning to frozen precooked pastas. These are available in most popular shapes, and whole-grain varieties are becoming more popular, too. With the gluten-free trend continuing to grow, noodles from alternate grains also are available. However, all of these products demand careful timing. Processors can work with suppliers to get the formula and timing right.

Grains and pastas are not the only uses of starch in a soup recipe. Thickening systems are integral for cream soups (and even some broth-based soups). A product line will have several needs for various thickening agents. While Grandma might have thickened her soups with the addition of flour, it is very unreliable. One cannot depend on the consistency of the protein and starch levels in flour or corn starch; these can break down easily or clump and separate if not supported within an overall stabilization system.

The most commonly used thickener is a modified corn starch, although potato starch and tapioca also are common. A frozen finished product will be having a different need than a low-acid product. The temperature a finished product reaches is another challenge to a thickening agent. For example, if a starch has a full bloom or swell at 185°F for 20 minutes, but a cream soup will scorch at that temperature and duration, alternative thickeners or stabilizers will be needed.

Increasingly used are functional starch forms; that is, modified and unmodified starches, functional flours and even functional native starches such as gums, dextrins and polysaccharrides, including carageenan, guar gum, locust bean gum or xanthan gum. (The FDA even has approved the use of acacia gum—also called gum Arabic—in food formulations, such as soup.) These starches have the “backbone of strength” needed for many applications. They’ve been especially designed to withstand select levels of heat, acidity, moisture, cooking duration and any other parameter chefs can throw at them.

Going to Pot

Equipment is often relegated to an afterthought, but the equipment on board for any type of soup can dictate much of what the processor can and cannot do. Today’s technology offers many choices in kettles. Choices can include steam-jacketed or steam-injection kettles; horizontal or upright kettles; kettles with agitation and without; and lidded or open.

Today, horizontal kettles have become highly popular. This is because of their advanced surface efficiency, as well as increased agitation surface efficiency. Agitation can be extremely critical when concerned with kettle scorch. More surface contact with more revolutions will reduce the chances of scorch, however.

Lids are another option. Most kettles have lids, and they help prevent loss from evaporation, retain heat and prevent contamination. But, for formulations that rely on evaporation or a reduction-type process to achieve a required finished profile, an easily adjustable lid is essential.

Proper agitation also is critical for an even cooking of ingredients. Soups are more sensitive than some formulations to these conditions, because of the multiple textures and densities of the ingredients in the total soup matrix. Without proper agitation, or due to uneven temperature distribution, the consistency of a particulate can be lost in the kettle. Part of the product will overcook in some hot spots; other parts will be undercooked in the colder areas.

Depending on a manual agitation process is inconsistent, leading to inconsistent results and out-of-spec finished products. In fact, it is unreasonable to expect to agitate manually any soup batch greater than 125 gallons. Mechanical agitation also is imperative for product transfer out of the kettle, especially in the case of a closed, Clean in Place (CIP) system. Also, a manual extraction process, such as would be done with a tilt kettle, to transfer cooked soup to vessels is highly unreliable, and it’s nearly impossible to control particulate distribution.

Steam injection can increase efficiency of a kettle soup manufacturing process. This is done by typically adding a wand along the center agitation post that induces steam. There are pros and cons to steam injection. The top advantages to the steam-injection method is that it reduces cook time and increases even temperature distribution. Shorter cook time reduces risk of scorch or even eliminates it, especially with the option of early termination of the surface heat. The steam is an addition to the kettle surface heat—or the preparer can leave the surface heat off and only use stream if it benefits the end-product.

The challenge with the steam injection is that it does add water to the product; this means the soup formula must be adjusted to compensate for the water added thru the steam. For cream-based soups, however, manipulating ratios of cream to milk or total liquid can compensate. Or, dairy concentrates can be used if acceptable.

Just Chillin’

Of course, boosting the heat with steam raises the issue of cooling a soup product so that it does not continue to cook beyond the needed time. With a batch product, less surface area means more contained heat within the formulation and, thus, slower decline in cooking temperatures. Moreover, surface parts cease cooking, while internal sections continue to break down from heat. Chilling in the same kettle can be easily effected in a jacketed kettle that allows the user to shift to cold water in the jackets.

There are kettles that both cook and chill, and do not require additional equipment to chill the products other than freezing capabilities. The drawback to this process is it can limit output, as the kettles are tied up chilling while they could be producing another batch. For this reason, some manufacturers may wish to invest in separate chilling equipment.

Spiral chillers are now a common method of chilling soup-like products. The corkscrew-type conveyor belts move product from the bottom upward (or vice versa) with cascading, chilled water continuously covering the packaged products. The speed at which the belts move will depend on the volume in the container or packaging. The larger the package size, the slower the belt. In most cases, the chill must go below 40°F in less than four hours. Other options for chilling are large water baths. These can work for smaller capacity products. Such options do take up more space than a more preferred spiral chiller, for example, but can be ideal for pouches.

In many situations, the packaging is more critical than the cooking of the soup. After the soup base is brought to the acceptable temperature, it goes through a heat exchange cooling system before going into the packaging along with the particulate. There are many different systems in this arena. Several aspects of the process moving forward must be evaluated, such as attaining even distribution of particulates while removing finished product from the kettle. Also, how much does the product temperature drop during the process of removing the soup? The timing from cook to chill to package to store has to be controlled, consistent and perfect.

Several options are available for packaging. Hot fill—mostly for fresh-made products or products needing an extended shelflife—involves pouches from 4oz to up to 10lb. Smaller packages mean longer packaging times, which can cause problems, especially if particulates are in the product, since they might not hold their integrity under the extended time in the kettle.

Cold-fill products are most often, if not always, frozen. The benefit to this is that the products do not have to be brought to as high a temperature in the cooking process. This can protect product integrity. However, these products will need to be heated for a longer time by the end-user.

Another cold-fill packaging method also used is a dual-phase process. Dual-phase processing is where the broth or cream bases and the particulates portion of the soup are prepared in different vessels, then simultaneously pumped into the packaging on the production line. This is most commonly used for frozen products that are reheated at lower temperature. Commonly, the particulates also can be placed in the pouch first, then top-filled with the broth- or cream-based portion before sealing and freezing.