To declare that fruits and vegetables are hot right now would be an understatement. The health benefits of fruits and vegetables are well-documented (“Eat the rainbow,” as parents tell kids). Yet Americans still fall behind on the minimum, “five a day” recommended daily servings. People consume an average of only 1.1 servings of fruit per day and just 1.8 servings of vegetables, according to the CDC.
Meanwhile, the USDA is upping the ante on what is needed for optimum health, and in 2010, increased the daily guidelines to nine servings of plant-based foods.. In fact, the MyPlate campaign recommends filling up half the plate of every meal with vegetables and fruits.
Eating the recommended servings of fruits and vegetables, plus increasing the ever-expanding variety of available produce, decreases the risk of many diseases. These include cancer, hypertension, stroke, heart disease, obesity and diabetes. Increasing intake (through produce) of nutrients they often lack—such as vitamins (especially A, B, C and K), minerals, fiber and phytochemicals, better enables human bodies to counteract DNA- and cell-damaging oxygen-free radicals, boost immunity and optimize metabolic function.
On the chef scene, top chefs in most of the country’s food meccas are adding more vegetable-as-center-of-the-plate dishes to their menus. And in some venues, like Vedge in Philadelphia and Dirt Candy in New York, chefs are turning entire menus into vegetable extravaganzas. While the current trend is not to go completely meat-free, the attention is on the garden basket—building great dishes with plants and letting the animal protein take a back seat.
From Chef to Shelf
Moving plant-based dishes to the center of the plate is a “no-brainer” for restaurant chefs. Vegetables and fruit offer a variety of flavors, textures, aromas and visual appeal that can’t always be achieved with animal protein. Also, with increasing focus on sustainability and the impact the meat industry has on the economy and environment, today’s culinarians know that more vegetable items translate to happier eco-minded consumers. Couple this with the health benefits of eating vegetarian at least once a week, and meal makers reap big rewards from upping the vegetable- and fruit-based offerings available to consumers.
This leads to the development kitchen and how product developers can best take this growing trend and incorporate it into new lines. Whether the challenge is to make veggie- and fruit-centric products or to appeal to the omnivore looking to increase overall plant intake, developers have abundant opportunities. Options include the expanded ingredient choice assets of produce, as well as advanced formats now available thanks to produce and produce ingredient providers.
Fruit- and vegetable-based products range from fresh-cut pieces to spray-dried powders, and emerging technology is creating new products every day to assist with product creation. While cost and function typically rule the day, the ready acceptance in the market gives food makers more leeway to keep quality high.
“As a developer, you need to dig deeper into how a product is actually used in order to make it work in your application,” says Webb Girard, a food scientist for Seattle-based food product development consulting firm CuliNex LLC. “For example, if you’re making an edamame ‘hummus,’ it’s important to understand that edamame’s green color is not stable and can bleach out under the florescent lights in a supermarket setting. In such a case, spinach powder can be included to provide a nice, bright green color, making it a natural and even healthful choice to solve the problem.”
Another example Girard notes is using fruit as a flavoring in cooked or smoked formulations. While fruit juice concentrate is more expensive than fully diluted juice, in a product where processing includes cooking, smoking or evaporation—as with a smoked sausage or jerky product—a concentrate will save the bottom line. While using the regular-strength fruit juice at first seems cost effective, it is likely more juice will be needed to fully flavor the final product (or get the full functional benefits of the fruit).
It also will add prep steps and increase cook time. A significant portion of that delicious fruit juice is going to end up on the oven floor through evaporation.
By contrast, using a fruit juice concentrate in such a formulation will allow the developer to reduce the amount of moisture going into the product, while achieving the flavor and functional benefit desired. The result can be a more intensely flavored product that takes less time to cook.
In some products, a multi-pronged approach can be best to get desired results. In a frozen pasta entrée, such as lasagna, in order to balance the overall moisture content with texture, visual appeal and flavor, there are multiple tomato products from which to choose. A dehydro-frozen tomato added to a traditional sauce will bind moisture and improve texture and water activity, controlling syneresis (weeping) when the product is thawed and cooked. However, adding a little tomato powder can help brighten the sauce’s color and assist with water migration. It also will intensify the tomato flavor, actually helping it taste more “fresh” and increase the nutrient value.
It can’t get better than fresh, right? It might surprise many consumers, but from both a nutrition and flavor standpoint, that’s not always true. The issue with using fresh fruits and vegetables for development is just that—they’re fresh, therefore highly perishable and susceptible to breakdown that destroys both flavor and nutrients. Although a seemingly fresh strawberry glistening on the produce shelf has high appeal for a consumer, it differs in many ways from, for example, the strawberries that were processed and flash-frozen at -20°F in the field within minutes of picking.
Fresh produce presents other issues for the food technologist to consider, including moisture level, fiber content, fragrance, flavor and nutrition content. Returning to that strawberry, all these qualities can differ significantly from the berry to the left or right of it on the shelf—variables include season; where and when it was picked; how much water, sunshine and nutrients it received; how many days passed between when it was plucked from the plant to reaching its destination, etc. So, developing with fresh fruits and vegetables is not as easy as grabbing the best-looking produce from the shelf.
“Fresh produce is wonderful but tends to vary depending on the time of the year and all the variables of weather and nature,” agrees Robert Del Grande, executive chef of RDG + Bar Annie in Houston and one of the only restaurant chefs in the world with a PhD in organic chemistry.
“The ability to sort and use the produce by all its various criteria within a certain time frame is challenging. We always say, no two carrots are ever exactly the same. In development, you have to base your formula on the ‘mean quality’ of the products you hope to use,” says Del Grande.
A concurrent challenge to formulating foods for batch production using fresh produce is food safety.
“Fresh produce in a refrigerated product will need a ‘kill step’ or anti- microbioligical additive to stave off food-borne pathogens,” says Girard. “If the product is assembled with fresh produce and designed to sit in a refrigerator case after production, steps need to be taken to make that finished product safe. Often, fresh and frozen produce don’t go through their own kill step prior to distribution.”
Chemical qualities also vary, depending on the vegetable in use; this is often not taken into consideration.
“Certain vegetables, whose flavors change post-harvest or post-processing, are problematic,” says Del Grande. “Peeled garlic is a perfect example: As it ages, even over a few days, the flavor grows stronger and [more] assertive. Therefore, the same quantity of garlic can deliver a completely different flavor characteristic and impact.”
Many types of produce experience flavor fade after harvesting and picking. Or certain flavors fade and others grow (broccoli is a good example), or the item might develop bitter back-notes.
“Color in certain vegetables also is of concern,” adds Del Grande. “The red color of fresh chili peppers is never consistent, but the brilliant red color is highly desirable. And with fruits, there always is the ripeness issue. Everyone loves a perfect, ripe mango, but ‘perfectly ripe’ is difficult to achieve as the quantity needs expand.”
Other fresh produce problems concerning color are that, especially as produce is grown for its visual attributes as much as its other qualities, the color does not always translate to the level of ripeness or the intensity of flavor.
Working with fresh produce in the pilot or test plant and then moving on to full production runs has some unique pitfalls. Once a product is ready for the production floor, Del Grande cautions, the processor must be wary of an “over-dependence” on the outcome on a single product.
“If chili peppers for a sauce are not perfectly red, for example, then the sauce will look pale,” he says. “We try to couple ingredients together for the desired effect, so the shortcoming of one can be compensated by another.”
One beverage company, Fresh Promise Foods Inc., has taken advantage of new high-pressure processing (HPP) technology to get the most out of formulating with fresh produce. Products in the company’s unique Harvest Soul Chewable Juice are blends of non-GMO, all-organic vegetables and fruits (mixed with nuts, seeds and berries) blended just short of puréed, without heat pasteurization, to retain produce’s naturally high-fiber levels, as well as good protein, without any additives. HPP keeps the thick beverages flavorful and safe.
Del Grande further points out that few formulations are exactly linear in a large scale-up. “We look for ingredients than can buffer the deviations for the linear line. For example, garlic doesn’t always scale up in a linear fashion–no two cloves are exactly the same. We usually downplay the garlic quantities and use additional onion—a gentler allium flavor—to buffer the flavor profile, especially if an overt garlic profile will be rejected as flawed by the end-user.”
Where fresh produce is desired or even required, “freshlike”—frozen and individually quick frozen (IQF) versions—can be excellent, convenient and even lower-cost substitutes. Most varieties are available, sometimes with added salt, acid and/or sweetener, sometimes not. They have lengthy shelflives and improved nutritionals since, as pointed out, they typically are frozen at the peak of nutritional content without suffering the loss of nutrients incurred by long transport, storage times, and exposure to light and air.
Formulating with frozen produce has its challenges, however. The freezing process, no matter how sophisticated and innovative, still results in some texture loss and, in most cases, increased saturation. This is due to the rupturing of plant cells which release water when the item is thawed. Care should be taken to adjust the moisture level of other ingredients in a formula to ensure texture, water activity and other affected aspects stay within project parameters.
It is possible to source fruits and vegetables that have been processed into liquid format at every viscosity imaginable. Commonly available forms include juice, juice concentrate, single-strength purées, and concentrated purées and variegates.
Fruit juices are simply fresh or frozen fruit crushed and pressed, filtered, pasteurized, packaged and sometimes frozen. Concentrates are juices that have been heated or enzyme-treated to remove pectin and starch. They’re then filtered and concentrated through evaporation to remove water. Juices come in a variety of strengths, as well.
Single-strength juice is great for adding moisture and subtle flavor, while juice concentrates can be an inexpensive way to add fruits and vegetables, especially when one wants to make a fruit or vegetable label claim (i.e., “contains two whole servings for of vegetables”).
Expect to pay a premium for the more exotic fruits and vegetables, or for produce with branded names (i.e., San Marzano tomatoes). Also, some more popular fruits and vegetables can be more expensive. Moreover, while frozen or juice preparations of produce can be less susceptible to seasonality and accompanying price fluctuations, they still are subject to standard supply-demand economics.
To mitigate cost, consider using a blend. For example, a peach or berry juice cut with less expensive apple or white grape juice has become a common way of including the more “sexy” fruit on the label yet keeping costs down.
Purées are fresh or frozen fruit that has been crushed and pasteurized. Concentrated purées are heat- or enzyme-treated to remove pectin and starch. They then are filtered and concentrated through evaporation to remove water, just as are juice concentrates. Purées are pure, simple, clean and can be concentrated down to specific brix (sugar content within the liquid solution), but they often are made with B-grade produce and don’t necessarily provide the fresh, just-picked flavors of higher-end variegates and preparations. When using these “straight shooters,” it sometimes is necessary to augment with flavorings to make up for lost top-notes or imperfect flavors.
Formulated preparations and variegates are intensely flavored, high-end purées formulated with sweeteners, flavorings and sometimes even fibers or gums. They are designed to create a tasty, consistent and functional product. These ingredients are at their most efficacious in products like ice cream, yogurt, baked goods and beverages. They are used where an attractive swirl of a brightly colored, intensely flavored fruit is needed.
From a functional perspective, some purées offer advantages beyond flavor. They can act as humectants, antimicrobials and mold inhibitors, giving developers natural alternatives to artificial additives. Purées and concentrates made from prunes, for example, are being used to add and retain moisture in a variety of foods. Boasting a natural sorbitol content of nearly 15%, prunes, prune concentrate and prune purée act as powerful hygroscopics to keep products such as bakery goods soft and moist.
At Sunsweet Growers Inc., ingredient technologists have made great strides in using prune concentrate to improve the shelflife, texture and flavor of meat, without adding sugar, salt, phosphates or preservatives. The high sorbitol content that helps baked goods stay moist also keeps meat juicy, and the malic acid content helps to inhibit microbial spoilage and retard mold growth.
When using these “wet” produce ingredients in a formulation, the focus should be on whether that ingredient is being used primarily to give the product fruit flavor or functionality. While both certainly are compatible—and in many products today, desirable—if the specific flavor is desired but limited by budget, a single- strength purée can be used, and then augmented with flavoring.
This approach is exemplified by the difference between, say a “mixed berry” product vs. “raspberry.”
“If a fruit or vegetable ingredient is needed specifically for function—texture, for example—it’s best to choose a subtly flavored product with no color or flavor,” suggests Emily Munday, nutritionist/culinologist and development chef for Tree Top Inc., makers of apple juice, apple sauce and other retail apple products.
A common concern when using vegetable and fruit purées is natural sugar content. Because of this, processors can exercise more control by investigating process points and adding a purée as late in the process as possible to avoid flavor flash-off, overcooking and/or scorching.
How Dry I Am
Advances in drying technology have vastly improved the quality of produce powders. The pale, slightly cooked and inferior-tasting products of the past have been replaced with brightly hued, vibrantly flavored nutritional powerhouses that not only provide organoleptic appeal but also pack nutritional punch. These new approaches, from low-heat spray-drying to freeze-drying to microwave-assisted processes and light evaporation, allow vital nutrients and phytochemicals to remain intact and color and flavor to stay vivid.
Classic, drum-dried powders are made by drying juices or purées in high-capacity drums that rotate and heat at relatively low temperatures. The resulting sheets of dried product are then ground into a fine powder. Using this traditional method gives a relatively consistent product. However, depending on the manufacturer, the flavor quality can vary—ranging from cooked, jam-like flavors to overly caramelized or even burnt notes.
Spray-dried powders take a similar journey, although instead of tumbling in a drum, the purée is sprayed into a chamber, where it hits slightly warm air (below 125°F), then quickly dries and falls to the bottom of the chamber. The resulting mass is ground into a fine powder that imparts concentrated flavor and vibrant color.
Another remarkable new technology in the world of fruit and vegetable powders is light-driven evaporation. This process gently removes water while keeping color, flavor and nutrients intact. This innovative technology results in uniformly shaped, non-porous granules that are moisture-resistant with low surface tension. This means intense, vibrant concentrated flavor—much stronger than that which is achieved through drum- or spray-drying—can positively affect end-costs. More intense flavor means lower product usage to achieve equivalent results.
More conventional treatments are no less interesting or innovative. Some fruit and vegetable ingredient makers utilize BIRS process, a system that combines slightly warm air (about 30°C/86°F) at ultra-low humidity (3% RH) with gravity to dry the product. Modern versions of this system can be quite large, such as the 75-meter (250-foot) BIRS tower in Burgdorf, Switzerland.
Produce, even dense produce such as carrots, are converted to pulp. The system gently sends droplets of the pulp from the top of the tower down, where it encounters the warm air from a ground blower that slowly dries the pulp to powder. Much slower than conventional spray- or drum-drying systems, the slower drying provides better color, flavor and nutrient retention.
Using fruit and vegetable powders can enhance color and flavor and allow for stronger nutrition claims. In addition, some powders contain high levels of fiber, making them very useful for texture and moisture retention. Powders of already dried fruits, such as from prune, apple, raisin and date, contain both soluble and insoluble fibers that, in addition to nutrition benefits, also help bind water, adding tenderness and improving texture.
The previously noted levels of sorbitol in these dried fruits, especially in prunes, assists further with water activity, increases batter stability in baked goods and improves moisture. While cost can be an issue, it takes a relatively small amount of fruit or vegetable powder to reap the functional benefits. Experts recommend starting with adding as little as 2-5% of the total formula.
Slice, Dice…and Dry
As with pulverizing produce, fruit and vegetable processors are equally adept at creating dehydrated products to add organoleptic and functional qualities to food products. Ranging in use from simple flavor or color enhancement to assisting with moisture retention and migration, dehydrated produce comes in multiple forms. Generally speaking, dehydrated and freeze-dried produce retains its color, flavor and nutritional value.
The move to dried fruits, especially superfruits such as berries and cherries, reflects the nutrition, taste, color and versatility of these fruits. Blueberries are still trending up as favored superfruits for formulations. According to the US Highbush Blueberry Council, consumers have indicated that blueberries in an ingredient statement say “wholesome” and “natural,” and they “view blueberries as a value-added, healthy ingredient.” Berries such as dried blueberries (and other formats) can allow for reductions in sugar, high-fructose corn syrup or other sweeteners, as well.
One rising star lately has been tart cherries. “In terms of product form, there is a strong shift toward dried tart cherries,” says Jeff Manning, CMO of the Cherry Marketing Institute.
“Increasingly, dried tart cherries are being blended into ‘high-antioxidant’ snack mixes. They also are being combined with more savory flavors and entrées. This surge in tart cherry ingredient use is being driven by their strong nutrition profile, their unique sweet-tart flavor and the bright red color they add to formulations,” Manning states.
Dehydrated inclusions are made by cutting or slicing the produce and dehydrating it to the desired level. Often, products can be further processed with flavors, coatings or additional cutting. Freeze-dried produce is achieved by nitrogen-freezing it (or sometimes a combination of frozen nitrogen and liquid methanol) to between -50°C (-58°F) to -80°C (-112°F) in a two-step drying process, during which the produce is subjected to a partial vacuum that helps wick away moisture without raising the heat significantly.
Freeze-dried produce (whole or in discreet cuts) also boasts the benefit of retaining shape and size. This is a definite boon for those applications, such as dry soup and rice mixes, where visual appeal is important. The rehydrated produce will come quite close to visually resembling fresh upon rehydration. It should be noted, however, that the rehydrated produce will have a different texture than fresh.
Technology ranging from pasteurization of fresh fruits to blending drum-dried fruits to improve cost, or adding coconut water to fruit juices to reduce sugar and sweetness, provide endless options for cost and health-conscious developers.
Fruit and vegetable inclusions can be pricey but have big impact on the appearance of the final product. If cost is an issue, using a very small piece size can show abundance. If using dried fruit pieces in batter applications, smaller pieces also will be favorable over large pieces, as they stay suspended in baked goods, providing even ingredient disbursement and a more appealing product.
In addition to the obvious inclusion in baked goods and dry blends, fruit and vegetable pieces also make their way into savory applications, assisting not only with flavor, color and aroma, but also used as fat replacers, thickeners, humectants and bases for more complex flavor profiles. This is a significant advantage, not only for consumers seeking healthier yet still flavorful food options, but for marketers as well. Produce and produce products are not “new” news in the industry, but new forms, functions and application occasions open up a new world of possibilities to the food developer.
Taking the Cure
Vegetable powders present functional assistance for creating today’s meat products. Beet, celery and rosemary powders are used as natural preservatives and nitrite replacements, allowing manufacturers of cured meats and similar products increased clean label options, while maintaining the rosy pink color and familiar, pleasant toothsome-but-yielding quality of high-end cured meats consumers expect.
While perfectly suitable for “uncured” label claims, nutrition and health experts are quick to point out that a nitrite, even naturally derived, is still a nitrite. So, as consumers become increasingly concerned about the ingredients in their food, manufacturers could find that using such “natural cures” could be considered equally dubious to using conventional nitrites. In addition, until very recently, formulating with these products was tricky, at best—not always yielding perfect results.
As recently as 10 years ago, food manufacturers had to calculate the conversion of plant-based nitrates into nitrites themselves, bringing in cultures and managing the process manually. This resulted in several challenging issues: First, the resulting nitrite levels were often too low to meet the desired 25,000-28,000ppm. Second, products made with these early-adopted powders often had off vegetal flavor notes and tinges of green coloring due to the large amount of celery powder needed to reach proper curing levels. Finally, the process proved to be inconsistent with varying levels of nitrite from batch to batch, making it nearly impossible to get a consistent product off the line.
However, developers have come up with new and improved natural cures that do the converting for the manufacturer. While the previous versions of pre-converted natural nitrite ingredients contained approximately 10,000ppm sodium nitrite, they also had the similar limitations of nitrate-based ingredients—negative flavor, color and aroma being the primary complaints. The latest versions seek to make the use of natural cures even simpler.
Today’s converted natural curing ingredients contain approximately 40,000ppm nitrate equivalent (roughly 15,000ppm sodium nitrite equivalent) and can be used at much lower levels than their predecessors. In addition, natural cure manufacturers have refined flavor, color and aroma profiles to make the off-colors of previous versions a thing of the past.
Anibal Concha-Meyer, Ph.D.
There is huge potential in finding food ingredients and bioactive compounds from agribusiness byproducts. Much effort in produce ingredient science has moved toward research and discovering added value from a diversity of food “residues,” resulting in many components of interest for the food industry. Byproducts of processing, peeling, cutting, milling and blanching, etc., include parts such as peel, seeds and discarded pulp that are rich in bioactive nutrients. Polyphenols, antioxidants, colorants and other compounds are examples.
These can be treated and re-applied with the secondary positive impact of reducing the waste material volume produced by most of the agricultural industry. Examples include products such as tomato paste that discards most of the skin which is rich in lycopene; seeds that are rich in essential fatty acids; and good fiber. Olive pomace—the residue from olive oil production—also is rich in polyphenols, such as tyrosol and hydroxytyrosol. These have well-known health benefits for humans.
These secondary products become the bioactive ingredients, colorants and other technological solutions for processors, performing such functions in formulation as antioxidant, anti-browning factors. Best of all, since they are derived from fruits and vegetables, they are a boon for food and beverage companies seeking a natural/eco-friendly/clean label.
Anibal Concha-Meyer, PhD, is a fruit and vegetable product development scientist and research coordinator at the Centro de Estudios en Alimentos Procesados (CEAP) in Talca, Chile. His primary areas of research are food and beverage product creation, food safety and food microbiology. He can be reached at firstname.lastname@example.org.