How can kitchen professionals manage their production volume with less manpower without compromising on quality? Does time-shifted cooking solve the problem? If yes, which requirements have to be met for this? By Dieter Mailander, mailander marketing
Better known than any summer hit is currently the dirge from employers in many sectors, who are looking for labor all across the European Union, but don’t find enough – not even in the restaurant and the hotel industry. According to overviews of the German Federal Statistical Office, 9.5 million people worked in this sector three years ago. However, there were fewer than 8 million people working in the sector last year. That is a loss of 16%. This year, the number of employed will continue to decline in all probability. The development of the demographic pyramid of the Union suggests that this topic will still accompany us for quite some time: perhaps it will even develop into an ongoing topic.
A Recipe for Staff Shortages: Time-Shifted Production
But restaurateurs, chefs, and hoteliers can take measures in order to dampen these effects. For example, they can completely change their workflow and change from classic fresh cuisine over to a time-shifted partial or full production with blast chilling and shock freezing. But the prerequisite is that they invest in appropriate equipment and storage capacity as well as educating their personnel well.
The investments will be paid off by lowering their costs for personnel, goods, and production. The processes of blast chilling and shock frosting (both usually run in one device) are known in their basic features. The production is planned several days in advance and then implemented exactly according to plan (short-term changes are difficult). The food or the components are cooked until done, whereby the regeneration (the remaining cooking time) must be taken into consideration.
The storage time is usually up to five days. Immediately after cooking, therefore hot, the dishes or components are slid into the cooling device in GN containers or in portions. The higher the difference between the temperature of the dish and the cooling ambient air, the more effective the surrounding air of the dish extracts its warmth, which it emits to the vaporizer. The more powerful the refrigeration unit is and the more efficient the air is distributed in the device, the higher the cooling capacity is. In any case, it makes sense to pre-cool the device.
Speed is Trump
If food is to be blast chilled, its core temperature must be lowered within 90 minutes down to 3° C for hygienic as well as culinary reasons. It makes sense to use two different devices for this purpose. Fluid and pasty foodstuffs like stews, puddings, or purees have a high density. That’s why they keep their core temperatures very long and form quickly a skim on their surfaces. In a cooking and recooling kettle, these foods are stirred continually and thereby cooled down more evenly and faster without forming skim in comparison to convection cooling.
However, other dishes such as casseroles, stir-fry dishes, sliced roasts, or fish may not be stirred anymore after the cooking process. One uses the air circulation from the blast chillers in order to blast chill them. If the dishes are shock frosted, they must reach a temperature of -18° C within 240 minutes at the core. For this task, one uses the function “shock freezing” of the air circulation unit. This tight time frame is important for two reasons among others: With blast chilling and shock freezing, pathogenic microorganisms such as bacteria multiply between 65° and 10° C very strongly, partly even exponential; above 65° C, one is in the temperature range of pasteurization which stops this growth. With shock freezing, the process temperature sinks down to minus 40° C and puts any germ activity into a cold deep sleep.
The more efficient this process runs, the more actively the so-called microcrystals form. They don’t damage the cell structures of the food due to their small size. That has several positive effects: Moisture and liquid remain just as largely preserved as nutrients, especially vitamins. The dishes retain their color and keep their taste. Of course, one can’t beat this type of production of masterfully cooked dishes culinarily that are eaten fresh. This is also not the claim. But everywhere there, where à la minute isn’t possible, one can offer a culinary performance for his or her guests, patients, or residents, which pleasantly surprises most of them. Speed, temperature, and moisture are key parameters of both of these processes. No refrigerator, no freezer, and no cold store are able to deliver this accomplishment. That’s why they are totally unsuitable for blast chilling.
To read the entire article, please access your complimentary e-copy of Frozen Food Europe September-October, 2022 issue here.