Food items zada der bahar rakhne se kharab kyu hota hai? Aur fridge khane ko kharab kese nhi hone deta?
Food items ek structure ki bani hoti hai. Iss structure mein protein, fat, water, aur carbohydrates jessi cheeze naturally hoti hai. Structure damage hone se food items spoil ho jate hai. Food spoilage yani taste, appearance, aur smell mein change ajana.
Jab khana bahar rakhte hai to uska temperature badta hai aur uske oxygen ka khane ke sath sampark mein ane ke karan uska spoil hone ka process shuru ho jata hai.
Aur usme bacteria grow hona shuru ho jate hai. Ye microorganism sabse phele khane mein mojud protein ko consume krte hai. Jiski waje se khane ka structure disturb hota hai aur vo apne sare nutrients aur protein loose krne lagta hai.
Aur agar hum ussi khane ko fridge mai rakhenge to uska ka temperature 3 ya 4 degree celsius hota hai. Kam temperature hone ke karan khane mein microorganisms ki metabolic activities almost ruk jati hai, jisse vo normally function nhi kr pate aur unki growth ruk jati hai. Jisse khane ka structure maintain rahe.
Ye temperature unn food item ke liye best hai jinne aap 3 se 4 dino mein consume krne wale ho. Aur jinne items ko aap zada dino tak ya hafton tak fresh rakhna chahte ho, toh unko aap freezer mein bhi rakh sakte ho. Jaha per temperature -18℃ tak hota hai, jo kahne ke spoil hone ke process ko almost rook hi deta hai.
Food prevention and its stages
Home food preservation ghar pe khana conserve karne ka ek popular tareeka hai, jo 2020 mein zyada logon ke beech mein aur bhi popular ho gaya. Us waqt canning supplies jese ki jar lids aur canners ki kami ho gayi thi. Chalo, is topic ke origins pe ek nazar daalte hain.
National Center for Home Food Preservation ke mutabiq: “Jab bhi khana harvest hota hai, wo turant kharab hona shuru ho jata hai. Hamare purane ancestors ko survive karne ke liye kuch tareeke dhoondhne pade jo khana thande mahine tak fresh rakh sake. Thande climates mein, wo log meat ko barf pe freeze karte the; tropical climates mein, wo log dhoop mein khana sookhane ka tareeka istemal karte the. Ye purane methods ne ancient man ko ek jagah settle karne mein madad kiya aur communities banane mein bhi.”
Freezing ek aisa method tha jo cold areas mein kaam karta tha. Baad mein icehouses ka creation hua jahan ice aur khane ki items store kiye jaate the, jo bad mein iceboxes mein evolve hua. 1800s ke late 1800s mein, Clarence Birdseye ne discover kiya ki frozen meats aur vegetables ko jab jaldi aur very low temperatures pe freeze kiya jaye, toh wo behtar taste karte hain.
Canning ghar pe food preservation ka ek naya method hai. Canning ke process mein high temperatures aur cooling ke baad jar mein vacuum seal create hota hai. Iska goal ye hota hai ki microorganisms ko destroy kiya jaye aur enzymes ko inactive kiya jaye. Jab khana properly canned hote hain, vacuum seal microorganisms ko jar ke andar enter karne se rokta hai aur food ko contaminate hone se bachata hai.
National Center for Home Food Preservation kehta hai: “Canning ko 1790s mein Frenchman Nicolas Appert ne pioneer kiya. Usne discover kiya ki sealed glass bottles mein heat apply karne se khane ko spoilage se bachaya ja sakta hai. 1795 mein Napoleon ne ek award offer kiya tha jisne naye food preservation method ko develop karne ka challenge diya. Appert ne 1809 mein ye award jeeta. Appert ne ek successful method discover kiya, lekin us samay wo poori tarah se samajh nahi paya.
Usne socha ki air ko exclude karna preservation ka reason hai. Ye tab tak clear nahi hua jab 1864 mein Louis Pasteur ne microorganisms aur food spoilage ke beech ke relationship ko discover kiya. Pasteur ke discovery se pehle, Raymond Chevalier-Appert ne pressure retort (canner) patent kiya tha jo 212 degrees Fahrenheit se zyada temperature pe can karne ki suvidha deta tha. Lekin 1920s tak is method ki significance ko botulism prevention ke liye nahi samjha gaya.”
United States Department of Agriculture ke documents ke mutabiq, kuch notable achievements bhi hui thi jese ki 1812 mein Robert Ayars ne pehla American cannery open kiya aur 1858 mein John L. Mason ne Mason jar patent kiya. In discoveries ne home food preservation ko aage badhaya, jese ki 1884 mein Ball ne glass jars manufacture kiye aur 1903 mein home canning supply business shuru hua. Alexander H. Kerr ne 1915 mein two-piece disposable metal canning lid ka patent kiya jo aaj bhi home canning process mein use hota hai.
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