Perubahan Mutu Minyak Kelapa dan Minyak Sawit Selama Penggorengan

<p>Abstrak</p><p>Proses penggorengan akan menyebabkan perubahan mutu minyak akibat reaksi hidrolisis, oksidasi dan proses termal. Penelitian ini bertujuan untuk mengetahui perubahan mutu minyak kelapa dan minyak sawit selama penggorengan. Minyak kelapa dan minyak sawit masing-masing digunakan untuk menggoreng kentang pada suhu 170°C selama 15 menit. Minyak tersebut digunakan untuk 3 kali penggorengan. Pada akhir penggorengan dilakukan pengambilan sampel minyak untuk dievaluasi kadar air, kadar asam lemak bebas, bilangan peroksida dan bilangan TBA (Tiobarbituric acid). Hasil penelitian menunjukkan bahwa sebelum penggorengan minyak kelapa dan minyak sawit memiliki kadar air yang hampir sama, tetapi kadar asam lemak bebas, angka peroksida dan TBA minyak kelapa lebih rendah dibanding minyak sawit. Selama penggorengan minyak kelapa dan minyak sawit menunjukkan pola perubahan kadar air yang hampir sama. Pada 1 kali dan 2 kali penggorengan kadar asam lemak bebas, angka peroksida dan angka TBA minyak kelapa dan minyak sawit cenderung berfluktuasi. Pada 3 kali penggorengan minyak kelapa memiliki kadar asam lemak bebas, angka peroksida dan angka TBA yang lebih rendah dibandingkan minyak sawit. Hasil yang diperoleh menunjukkan bahwa minyak kelapa lebih stabil terhadap reaksi oksidasi dibanding minyak sawit selama penggorengan.</p><p> </p><p>Pattern of Coconut Oil and Palm Oil Quality During Frying</p><p>ABSTRACT</p><p> </p><p>Frying was a process which affected the quality of oil due to hydrolysis, oxidation and thermal reactions. The aim of the research was to study the quality pattern of coconut oil and palm oil quality during frying. The oils were utilized to fry french fries at 170°C for 15 minutes and then used in frying process for 3 times. Samples of oil were taken at the end of each frying period and analyzed for its moisture, free fatty acid, peroxide and TBA (tiobarbituric acid) values. The results showed that, coconut oil and palm oil having similary moisture content before and during frying. Otherwise free fatty acid, peroxide and TBA values at coconut oil lower then palm oil. During 1 and 2 times of frying period these two oils showed fluctuation in free fatty acid, peroxide and TBA values. During 3 times of frying, coconut oil contained free fatty acid, peroxide and TBA value lower than palm oi. Thus, we consider that coconut oil was more stable to oxidation compared to palm oil during frying</p>

STABLE SUDANOPHILIA OF HUMAN NEUTROPHIL LEUCOCYTES IN RELATION TO PEROXIDASE AND OXIDASE

It seems improbable that leucocyte oxidase is a fatty acid peroxide, as suggested by Sehrt, on these grounds: 1. Positive reactions for aldehyde and for ethylene groups are not obtained. Hence the presence of fatty acid peroxides in leucocytes seems unlikely. 2. Peroxidase has been isolated from leucocytes by Agner. Histochemical behavior on treatment with adverse reagents and with heat indicates similarity of benzidine peroxidase and of indophenol oxidase, but dissimilarity of these from the sudanophil substance in leucocytes. 3. Sudan dyes demonstrate or produce in neutrophil leucocytes deeply colored granules of quite variable size, and the size of the granules apparently increases with the duration of staining. 4. The demonstration of sudanophil granules in leucocytes is accomplished with difficulty. The colored granules are highly stable toward many Sudan dye solvents. Decolorization is difficult and recoloration is uncertain. 5. True fats and lipoids, after staining with Sudan dyes, are readily decolorized by appropriate dye solvents and are restainable in apparently undiminished amounts. 6. Some oxidants tend to impair sudanophilia of leucocytes. Potassium bichromate improves the preservation of sudanophil lipoids, as in the Ciaccio method, but destroys the sudanophilia of polymorphonuclear leucocytes. 7. Hydrogen peroxide apparently possesses an inconstant and irregular, though sometimes quite pronounced, accelerating effect on the production of Sudan stained granules in leucocytes. 8. The sudanophilia of leucocytes depends on an as yet unexplained chemical combination of the dyes with cytoplasmic constituents which are probably not in the form of preexisting granules, rather than on lipoid staining.