Total solid content in milk products comparison of two methods

S obzirom daje udjel suhe tvari/vlage jedan od važnih čimbenika koji određuje kakvoću bilo kojega prehrambenog proizvoda tijekom berbe, skladištenja, prerade i distribucije, kao i kontrole gotovih proizvoda, njegovo određivanje mora biti brzo, točno i precizno. Standardna laboratorijska metoda određivanja suhe tvari/vlage sušenjem do konstantne mase bazira se na uklanjanju vode iz malih količina uzorka evaporacijom, a vaganjem uzorka prije i nakon sušenja dobiva se željena informacija, što traje relativno dugo. Za brzo određivanje vlage mnogih prehrambenih proizvoda razvijene su brojne druge metode, od kojih je jedna i sušenje mikrovalovima u različitim modelima sušnica. "Milestone" MSL-1200 Mega System korištena je u ovom istraživanju. Cilj istraživanja bio je odrediti udjel suhe tvari standardnom metodom sušenja i metodom mikrovalnog sušenja u uzorcima pasteriziranog mlijeka i mliječnih proizvoda (fermentirani mliječni proizvodi, topljeni sirevi i sladoledi), dobivene rezultate statistički obraditi i interpretirati te utvrditi može li se metoda mikrovalnog sušenja koristiti kao relevantna. Za procjenu valjanosti analitičkih metoda razmatrani su parametri: preciznost, usporedivost metode i točnost. Izračunati statistički parametri pokazali su da nema statistički značajne razlike između dviju korištenih metoda s obzirom na udjel suhe tvari u svim istraživanim uzorcima (gledano u cjelini ili zasebno po skupinama mliječnih proizvoda), tj. metoda mikrovalnog sušenja može se koristiti kao brža, a istovremeno i precizna poput standardne metode.Considering that total solid/moisture is an important part in determining the quality of any food during harvesting, storage, processing or distribution, as well as final product control, it is essential to perform these analysis quickly and accurately. Standard procedures for determining total solid/moisture by drying until constant mass is achieved are based on removing water from small quantities of samples using evaporation techniques, and final results are obtained by weighing the sample before and after drying, which is time consuming method. For a rapid moisture determination in food products many other methods have been developed the one of which is the method of microwave drying using various models of microwave dryers, like "Milestone MLS -1200 Mega Systems" used in this research. The aim of this work was to determine the total solid content, using two methods, in numerous samples of pasteurized milk and milk products (milk, fermented milks, processed cheeses and ice creams). The obtained results are statistically evaluated in order to find out weather the microwave drying method could be used as relevant method. The assessment of analytical methods, was judged according to precision, reproducibility and accuracy. Statistical analysis showed that there was no significant difference between there two methods. It is suggested that the microwave method can be used as faster, precise and accurate method as a standard method