Hanna manufactures products with the necessary accuracy and reliability to check the quality of food in all phases of preparation and distribution while maintaining compliance with the law.
At Hanna, we recognise that temperature is an important parameter throughout many stages of the food production process; from manufacturing, pasteurisation, to storage - temperature measurement is essential. Indeed, our food thermometers are relied on by the main UK supermarkets and high street restaurant chains.
There are a variety of thermometer technologies that we sell to help you with your process, and meet legal requirement, by checking those important temperature measurements.
Here is a brief introduction to our range, and some help in what they may be used for.
Thermocouple thermometers provide a fast response and are capable of measurement at very high temperatures, they also provide moderate accuracy.
Thermistor thermometers offer high accuracy with a moderate response time within a limited temperature range. Hanna offers a variety of thermometers and application specific probes for all temperature measuring needs.
If you are looking for something simple, then look no further than at the HI-151 Checktemp4. It is the perfect portable, high-accuracy thermometer for home and professional kitchens. The sharp, stainless steel, fold-out probe is ideal when testing fresh, cooked and semi-frozen food.
Six colour-coded thermometers are available to meet the Food Hygiene and Hazard Analysis Critical Control Point (HACCP) regulations.
Why measuring temperature in food industry sectors is important and the temperatures to aim for
Meat
The temperature of meat at slaughterhouses is a vital quality control test and needs to be checked at various points of production. Fresh meat should be stored at about 2°C.
For deep-freeze meat in storage, it should have an internal temperature around -22°C with the surface temperature reaching -35°C. In order to thaw the meat properly, the surrounding temperature should be 7°C.
Ham and Sausages
The temperature of salted meat stored for several months is around 2°C. Afterwards, the product is rinsed and dried at around 25°C prior to maturing at a preset temperature for a particular product. For sausages, the mixed ingredients are cooked at a certain temperature and then cooled at around 5 to 15°C.
Milk and Dairy Products
Milk is checked for impurities and bacteria upon collection. During storage, the temperature of milk is normally kept below 5°C. In order to slow down cream formation, milk is homogenized at about 60°C.
The pasteurisation of milk results in the reduction of microorganisms by 95% and is attained by raising the temperature to over 72°C. For UHT (ultra heat treated), milk is heated to 135/150°C in a pressurised vessel for a few seconds. If the process is repeated for several minutes, all microorganisms, including spores, are destroyed and the sterilised milk will have a 12 month shelf life. For cheese, temperature needs to be adjusted before and during various processes, for example, when rennet is added.
Temperature in the maturation chamber also determines the period of maturation needed. Likewise, temperature is important in the production of butter. For example, skimmed milk is separated from cream at around 55°C and the cream is then cooled to about 8°C. The temperature of incoming milk is raised to 45°C before the addition of a culture for yogurt manufacturing. In order to denature the whey proteins, milk is raised to very high temperatures. The incubation temperature is maintained for a few hours prior to its cooling to about 10°C.
Chocolate
Fermentation of cocoa beans is started by increasing the temperature to about 50°C. At different stages of chocolate manufacturing such as crystallization, accurate temperature measurement is a must. Once the chocolate is ready, the storage temperature should be monitored to ensure that it stays in the 15°C range.
Confectioneries
In confectioneries, temperature of the sugar syrup will dictate the consistency of the final product. For caramel or other soft candies, the sugar syrup is heated to 121°C; a brittle hard candy, such as a lollipop, requires the sugar syrup to be heated to 148°C. A few degrees temperature variation may cause significant differences from one batch to the next. Thermistor thermometers, such as the HI-93501, offer a high level of accuracy for accurate temperature monitoring in the confectionery production process.
Bread and Pasta
The temperature of stored grain in silos is controlled to ensure that premature fermentation does not occur. During pasta production, water at about 25°C is added to wheat flour during fermentation of dough for bread-making, the temperature is kept at around 30°C. The oven temperature for baking should be around 260°C and once baked, bread is cooled to room temperature. For semi-finished products that can be flash-baked, the dough has to be stored at very low temperatures.
Beverages
The temperature of spring or deep well waters that are extracted for beverage production must be continuously monitored to ensure purity. During the production of soft drinks, syrup is pasteurized before being added, to prevent bacteriological problems. In order to prepare fruit juices, fruit pulp is heated to just below boiling point for a few seconds to reduce the presence of microorganisms. During both of these processes, accurate temperature monitoring is crucial.
Coffee
Coffee is one the favourite beverages consumed by billions of people worldwide. Coffee, no matter the brand and quality, can be affected drastically during the brewing stage. The water quality plays a vital role in determining the taste of the beverage. An equally important physical factor is the temperature of the water. Brewing is a chemical reaction between hot water and coffee. Overall, the brewing process extracts compounds from the coffee grounds; how these compounds are extracted is temperature-dependent. Slight variations in temperature affect the taste and aroma of the coffee. Colder water will result in less extraction, leaving the coffee tasting sour, weak and diluted, whereas, water that is too hot will cause over extraction, resulting in bitter and burnt tasting coffee.
In order to invoke an aroma, coffee beans are heated up to 200°C. During roasting, the temperature is closely monitored. In order to provide a long shelf life, the finished product is frozen at -40°C prior to drying. To produce a good coffee, it is important to ensure that the temperature of coffee machines does not exceed 80°C.
Brewing
At its core, all beer is made from the same 4 ingredients: water, yeast, hops and grain. Some brewers will choose to modify this basic recipe to include spices or fruits. Regardless of additives, all beers can be classified as either an ale or a lager based on which yeast is used: ale yeast or lager yeast. Temperature plays an important role in yeast fermentation and can be a deciding factor as to which style is chosen.
To begin, milled grains, such as barley and oats, are added to a large vessel called the mash tun. Hot water is added, activating malt enzymes from the grains which then convert the starches into fermentable sugars. The next step, called lautering, separates the sugary liquid known as wort from the spent grains. In order to end enzymatic activity, the temperature is brought to over 77°C, a process known as mashing out. The wort and some water is sent through the mash, removing any final sugars. Brewers can use temperature and time to manipulate which enzymes are active to bring out the desired sugars and influence taste. In general, lower mash temps increase fermentability while higher temperatures decrease it.
The wort goes through a series of boils while hops and other additives are added, and once cooled down, the yeast is pitched and thus begins the process of fermentation. Over the course of the next 7 to 10 days, the yeast will convert the simple sugars in the hopped wort into alcohol and carbon dioxide.
During fermentation, sugar from the grains are converted to ethanol and carbon dioxide via yeast. Ale yeast ferments best at higher temperatures, typically 18-21°C. At these warmer temperatures, fermentation speeds up, taking less time and also producing esters and phenols that add to the flavour. Lager yeasts ferment best at lower temperatures around 10-13°C. These yeasts tend to ferment slower, producing fewer phenols and creating a flavour more influenced by the hops and grains.
Sanitisation of Machinery
The temperature of cleansing agents, together with their concentration, have a significant bearing on how effectively the machinery is sanitised. The temperature for fermentation vessels can range from room temperature to 40°C. For milk and yogurt, tanks may reach 70°C and as high as 150°C for steam sterilisers. In addition, regulatory bodies recommend a certain minimum temperature for cleaning agents to be effective; this can vary from 24°C for iodine and ammonia and 49°C (120.2°F) for chlorine.
Refrigeration for transportation
Hanna also sells a range of thermologgers designed for keeping records of temperatures of goods being transported. Enquire now for more information.
