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School You know the difference between freeze-dried and dehydrated foods? Dehydration is the removal of water from the food by drying in the sun and air to or through the application of heat (such as in a greenhouse). The dehydration or lyophilization cold (freeze dry) is a process of preservation of organic products involving two methods of preserving biological products: superfrio and drying, do not use chemicals or preservatives and is the most appropriate to preserve cells, enzymes, vaccines, viruses, yeasts, serum, blood products, algae, as well as fruit, vegetables, meat, fish and food in general. In freeze drying the product is frozen to a very low temperature (below - 20 ° C), is subjected to a very low pressure (high vacuum), causing the water present in these products, has been transformed into ice, sublime, or pass directly from solid to gaseous state, resulting in a final product with a porous structure free of moisture and capable of being reconstituted by simply adding water. Thus, the lyophilized products do not change in size, texture, color, taste, smell, content of vitamins, minerals, proteins, etc.. When properly stored, even at room temperature resist very well. Lyophilized products are underweight, because most natural products has more than 80% water, are preserved even at room temperature and, when reconstituted, regain their original properties like no other product dehydrated. ACTIVITY Join packaging modified foods (powdered, dehydrated, freeze-dried, frozen, etc.) found in the market and are consumed daily. Then concoct posters with the class and make a presentation in school, putting next to the type of food the process by which it is modified. Each material has a different behavior when varying the conditions of temperature and pressure to which they are subjected. This behavior is characterized by physical-chemical properties of these materials. These properties serve to identify them. To prevent that in each study we calculate how these properties, they are generally found in tables. Solubility, density, melting point and boiling point, etc., are examples of physical and chemical properties of the materials. With the knowledge of physicochemical properties, we can predict the behavior of various materials used in construction, in aircraft, ships, medical and dental equipment and much more! Matter and Its Nature
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Škola Znate li razliku između liofilizirani i dehidriranu hranu? Dehidracija je uklanjanje vode iz hrane, sušenjem na suncu i zraku u ili kroz primjenu topline (kao u stakleniku). Dehidracija ili lyophilization hladna (zamrzavanje suha) je proces očuvanja organskih proizvoda koja uključuje dvije metode očuvanja biološke proizvode: superfrio i sušenja, ne koriste kemikalije ili konzervansa i najpogodnija je za očuvanje stanice, enzime, cjepiva, virusi, kvasci, seruma krvi proizvodi, alge, kao i voće, povrće, meso, riba i hrane u cjelini. U sušenje zamrzavanjem proizvod je zamrznut na vrlo niskim temperaturama (ispod - 20 ° C), podvrgnuta je vrlo nizak tlak (vakuum), uzrokujući vode prisutne u tim proizvodima, pretvorio u led, uzvišeno, ili Proći izravno iz krutog u plinovito stanje, što je rezultiralo u konačni proizvod s poroznu strukturu bez vlage i da je može rekonstituirati jednostavnim dodavanjem vode. Dakle, Lyophilized proizvodi ne mijenjaju veličinu, tekstura, boja, okus, miris, sadržaj vitamina, minerala, proteina, itd.. Kada se pravilno skladišteni, čak i na sobnoj temperaturi oduprijeti vrlo dobro. Lyophilized proizvodi su underweight, jer je većina prirodnih proizvoda ima više od 80% vode, sačuvani su čak i na sobnoj temperaturi, a, kada se rekonstituirati, vratiti svoje prirodne osobine kao što nitko drugi proizvod dehidrirana. AKTIVNOST Pridružite pakiranje modificirane hrane (u prahu, dehidrirana, liofilizirano, smrznuto, i sl.) nalaze na tržištu te se konzumira svakodnevno. Onda smisliti plakate s razredom i napraviti prezentaciju u školi, stavljajući uz vrstu hrane proces kojim se mijenjati. Svaki materijal ima drugačije ponašanje pri različitim uvjetima temperature i tlaka na kojoj su izloženi. Takvo ponašanje karakterizira fizikalno-kemijskih svojstava tih materijala. Te osobine služe kako bi ih identificirati. Da biste spriječili da se u svakoj studiji smo izračunati koliko je ta svojstva, oni se obično nalaze u tablicama. Topivost, gustoća, talište i vrelište, itd., su primjeri fizikalnih i kemijskih svojstava materijala. Uz poznavanje fizikalno-kemijskih svojstava, možemo predvidjeti ponašanje različitih materijala korištenih u izgradnji, u zrakoplovima, brodovima, medicinske i stomatološke opreme i još mnogo toga! materije i njezine prirode