Homemade in the factory

Consumers are a contrary lot. They love convenience food when they are ‘too busy’ to cook from scratch and they are so value-driven that they are forcing manufacturers and retailers into a never-ending race to drive down costs.

Yet at the same time one in two people doubt the food industry’s ability to meet the most basic requirement of selling food that is safe to eat, says Mintel senior food analyst Alex Beckett.

Only half of adults feel the UK food industry provides food that is safe to eat

Mintel analyst Alex Beckett

“That food should not be harmful should be one of the most basic of consumer expectations, yet only half of adults feel the UK food industry provides food that is safe to eat, signalling a widespread breakdown of trust in the agri-food chain,” he says.

Consumer mistrust of mass-produced food has given rise to a foodie fashion for all things rustic and artisanal, even though achieving a handmade appearance can be a hard trick to pull off for an industry that has worked for years to make consistent and repeatable products.

Last year, for instance, it was reported that Kraft Foods’ Oscar Mayer lunchmeat business in the US had developed a new cutting technique to give the company’s Carving Board brand of cooked meats the appearance of leftovers from yesterday’s roast dinner.

Development engineers said at the time that it took over two years to create a process that could mimic a person with a carving knife and cut each slice differently. Naturally enough after all that effort, the company is not saying much about how the process actually works.

Kraft is not alone in spotting the appeal of a hand-crafted appearance, and equipment suppliers have been busy devising ways to support manufacturers explore this niche across a range of food segments.

For example, the standard industry kit for cooking bacon is the linear microwave oven, but Unitherm Food Systems has patented the use of spiral ovens to give ready-cooked bacon a taste and appearance that is virtually indistinguishable from the pan-fried equivalent.

“It’s safe to say that the vast majority of producers pre-cooking bacon are using microwaves, a trend that developed when demand skyrocketed,” says Unitherm European sales and marketing director Camilla Howard.

“To date microwaves have been the only viable solution to meet production requirements. However the results are not at all natural or ‘home style’.”

Québec-based meat producer Olymel became an early adopter of Unitherm’s spiral oven technology for bacon at the end of 2012.

Olymel produces a variety of cooked and sliced meats, including gourmet products and the company’s Smart Nature brand. The company uses its spiral oven to cook bacon bits, pizza toppings and flaked bacon.

“Taste and appearance were deciding factors in the purchase of our spiral oven,” says plant manager Martin Croteau. “Both are important to the people who purchase our products.”

A natural looking and aesthetically pleasing product is one consumers are more likely to purchase

Unitherm’s Camilla Howard

Spiral ovens convey food upward on a continuous belt that travels in multiple, circular tiers inside a single oven enclosure. As bacon products cycle upward, fat is rendered from the ascending meat and disperses onto the bacon below. This bastes the bacon and provides the taste, aroma and appearance of a traditional, pan-fried product. As well as producing a more traditional taste, the spiral oven cooks wavy, natural-looking slices, in contrast to the flatter, duller looking products from microwave ovens, claims Unitherm.

“A natural looking and aesthetically pleasing product is one consumers are more likely to purchase,” says Howard. “After the initial purchase based on visual appearance, consumers base their decision for repurchase [on] flavour and texture. Unitherm’s spiral oven allows production of bacon at various levels of crispiness and colour based on the manufacturer’s preferences.”

Prepared meat may have a particular image problem to overcome, especially in Europe following the horsemeat scandal. However, the trend towards more rustic fare reaches far beyond that into a diverse range of processed foods.

“I think processed food is getting more and more a bad reputation,” says Thomas Pedersen, factory general manager of Quality Pellets in Denmark.

“There’s definitely a demand for more natural and handmade looking products and that’s a challenge for industrial processes.”

Quality Pellets makes snack pellets, which are dense, extruded intermediate products that are sold on to snack manufacturers.

The manufacturers turn them into finished snacks by cooking and puffing up the pellets using frying or hot-air expansion before adding flavours. Pellet production uses extruders to force dough (most commonly some combination of corn, wheat and/or potato) through one or more screws, where high pressure and friction heat and break down some of the components (gelatinisation). The gelatinised dough is then pushed out through specially shaped dies.

Screw results

This versatile process is great for making a wide range of 2D and 3D shapes, from simple cheese puffs to ghosts or bats for Halloween.

In recent years, the industry has tended to favour twin-screw extruders, largely because they promise tighter control and a more consistent result than single-screw machines. But Pedersen says that the success of Quality Pellets’ recent experiments into products with a more artisanal appearance relies precisely on the extra variability of a single-screw extruder.

“A lot of processing equipment in extrusion is made to make very consistent products, but that’s not what we’re looking for here,” says Pedersen. “A single screw gives more options in die design and how things come out of the process. It’s more difficult to control and handle single screw machines, which is why many people use twin-screw processes. But if you want a more varied result, single screw is good.”

Pedersen is wary about giving too many details about how the company has developed its new process, but he does provide a few clues.

“We can do things to the pressure going into the dies, so maybe the friction and speed is a little different on one part of the dough or the other,” he says.

“By varying the friction and the speed of the dough in the ‘backhead’ behind the die, we can do something that affects the curling afterwards when the pellet is cooked.”

The backhead is the section of the extruder just behind the die insert. Depending on the set-up, it may form multiple channels for the dough to flow through, or it may form one larger space.

“Many in our industry don’t pay much attention to this area, but we think it can be very useful,” says Pedersen. He says that the company has recently succeeded in developing a set-up that can make products that look more irregular and handmade than the usual pellet snacks.

“We’re pretty much there,” says Pedersen.

“We have the technology ready and the products are ready.”

Now it is just a question of getting Quality Pellets’ downstream manufacturing customers to buy into the idea.

Consistency and conformity is generally the goal in food production

Baker Perkins’ Keith Graham

One of the limitations on the degree of variability available to the pellet manufacturers is the need to control the pellet thickness so that they cook evenly in the snack manufacturer’s fryer or oven. However, there may be a little more flexibility in direct-expanded snacks and cereals.

These products skip the intermediate pellet stage and are typically extruded from the raw ingredients at the final snack manufacturer’s facility. In this case, snacks emerge fully cooked from the extruder and puff up as the pressure is released. Because they’re fully cooked during the extrusion process, the subsequent process step is drying, rather than frying or baking.

According to Keith Graham, marketing manager with equipment supplier Baker Perkins, the fact that direct-extruded snacks are dried rather than cooked following extrusion means there is a more leeway with the residence time in the dryer.

Because no browning of the product takes place, all the products can remain in the dryer until the thickest sections are sufficiently dry to optimise product quality and shelf life, without the thinner sections becoming too dark or overcooked.

“This opens up the possibility of making things different sizes because, within reason, you can dry them all down to the same moisture level without impacting on quality,” says Graham.

So, for example, a twin-screw extruder might have between 10 and 20 outlets, each producing product of a slightly different shape. “You can extrude products from each one with a slightly different profile,” he says.

For packaged foods in general, introducing variability in the appearance of products must be carefully controlled, otherwise it could cause big problems during packaging operations.

“Consistency and conformity is generally the goal in food production,” says Graham. “[This is] partly to make sure that the product goes through the packaging system okay and that the packs have the correct weight.”

Take chocolate chip cookies, for instance. Each lump of cookie dough deposited should be the same weight, although they can then be manipulated using clever cooking techniques to appear slightly irregular.

Although the specifics may vary, cookies, crackers and other baked goods typically all go through the same three stages during the cooking process: development, drying and colouring. The most crucial step for creating an irregular appearance is the development phase.

“If products are going to lift [form bubbles] or flow, that’s where it’s going to happen,” says Graham.

Key first steps

“So you might start with cookie dough in 30mm rounds and want it to flow to form 50mm rounds.

You’ll use pure radiation in the first stage and make sure the humidity remains high so they don’t dry out and form a crust that will prevent flowing.”

The development phase is also where uneven surface features are created. So in cream crackers, for example, the use of high radiant heat in the first phase results in ‘oven spring’ and bubbles forming.

The next step is drying, which sets the structure in place, and the final stage is colouring, where the surface browns.

If you have generated surface structures such as bubbles or fissures in the development stage, this is where they can result in an uneven colour.

Similarly, the cooking techniques deployed through an industrial baking process can be fine-tuned and combined in different ways to suit each product, but they’ll often include some combination of direct radiant heat and/or hot-air convection.

Direct-fired ovens can achieve a fast blast of heat that results in the dough spreading and/or the surface of the product cracking or bubbling during the development phase. In contrast, like a domestic fan oven, hot air convection provides very even heating and therefore a more-even final appearance.

At the end of the day, Graham warns that there is only so much variation that consumers will tolerate, whatever they may believe they want.

“Consistency and conformity are what consumers expect,” says Graham.

“They might want things to look different but they don’t want the eating quality to be affected. They don’t want some to be soggy, some to be dry and some to be bitter because they’re too dark. There’s actually a very limited range over which they’ll accept variation.”