Microwave in-pack pasteurisation gives chilled meals 30-day shelf-life

By Rick Pendrous

- Last updated on GMT

Related tags Food Cooking

Microwave in-pack pasteurisation gives chilled meals 30-day shelf-life
Imagine a superior chilled ready meal that doesn’t require extensive high-risk and low-risk production areas and has a shelf-life of 30 rather than the usual 14 days. Korma in the sky? Absolutely not.

Such products are available now from a new company that has set up business in Hayes, west London.

Hayes based S&R Foods is producing such products now, and is run by the former owner of Greenford-based Spurway Foods, Afzaal Hussain, a producer of samosa snacks who sold his business to Kerry Foods in 2006.

Kerry had acquired nearby ethnic food producer Noon Products the year before. S&R has teamed up with Andrew Niznik, who heads up Simply Microwave, which has the licence to sell the novel in-pack microwave pasteurisation technology from Swedish company MicVac in the UK and elsewhere. Niznik is a former technical director for Noon Products.

Hussain who set up the new business in December 2009 with members of his family recognised the huge potential of MicVac's technology to make a range of high-quality chilled ready meals, currently in Indian, Chinese and Italian variants. MicVac offers the unique selling point of a much longer shelf-life but without the need for costly production facilities and high staff numbers all thanks to the processing method.

Production started at the end of April 2010 and S&R's branded product 'Whistling Chef', is now on sale through Makro stores and independent retail outlets around the M25 corridor. It also supplies Rail Gourmet, which handles the catering for the major UK rail operators.

In June S&R Foods will start producing a range of meals for East End Foods, which will supply Tesco stores. "We are going to manufacture a range of Indian ready meals under the East End label, but with our technology," ​says Hussain. "At the moment in 50 selected stores but hopefully with a roll-out."​ Needless to say, he is also in talks with other multiples that have recognised the potential of this technology.

Whistling Chef

The name Whistling Chef plays upon the technology used to make the product. The meal packs make use of a special steam valve to allow products to be reheated by consumers. But what makes the MicVac technology so different from other valve-based ready meal approaches is the way meals are prepared and cooked in the factory.

Cooked sauce is added to a flexible tray, followed by raw protein and raw vegetables. The film lid containing a valve is then added, after which packs pass continuously through an industrial microwave oven. This cooks, for example, raw chicken and vegetables for two minutes at 98°C (the equivalent of 90°C for 10 minutes). Steam is produced, which is released by the valve, removing oxygen in the pack. Packs are resealed as the product cools and a vacuum forms, ensuring a bacteria-free product.

Simplicity itself

"It's so simple," ​says Hussain. "Take Chicken Jalfrezi, for example. We put chicken and vegetables on top [of cooked sauce] raw. And when you take it home and reheat it you've still got [texture] in those peppers."​ Another advantage is that, because of the extended shelf-life, longer production runs are possible, which also helps with allergen control.

While a shelf-life of 30 days is recommended by MicVac, independent laboratory analysis has shown that properly refrigerated products remain safe to eat for almost three months!

"Basically, you can [manufacture] most of what's on retail shelves now,"​ says Niznik. "But you can give it 30 days' chilled shelf-life with no preservatives or additives it's a step-change for the food industry."

All consumers have to do is take a pack from the fridge and reheat it in their microwave for around three minutes until a whistling sound is heard. At that point, the product is reheated, ready to eat no piercing of film is required nor stirring halfway through to mix the contents.

In contrast, traditional chilled ready meal packs are autoclaved or retorted in 12t batches for 1.52h from start to finish after preparation to cook products and ensure they are safe to eat.

The downside is that products towards the outside of ovens tend to be overcooked, since higher temperatures are required, to ensure that those in the middle receive adequate cooking time. Alternatively, cooked protein is added to the sauce in trays, in an operation requiring a high-care environment to avoid contamination.

Since the critical control point for the MicVac process is inside the sealed pack and cooking takes place continuously, the problems above are removed. And because cooking is carefully controlled, delicate ingredients such as vegetables are not overcooked S&R even adds fresh coriander leaves to some curries.

S&R Foods has a capacity to produce 10,000 meal a day, but Hussain is already planning to add an additional facility of 1,860m2​ nearby to allow for expansion and increase turnover to around £5M over the next couple of years.

Related topics Chilled foods

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