Rapid Assessment of Total Polar Material in Used Frying Oils Using Manganese Tetraphenylporphyrin Fluorescent Sensor with Enhanced Sensitivity

2020 ◽  
Vol 13 (11) ◽  
pp. 2080-2086
Author(s):  
Haiyang Gu ◽  
Xingyi Huang ◽  
Quansheng Chen ◽  
Yanhui Sun
2021 ◽  
Vol 13 (2) ◽  
pp. 561-570
Author(s):  
R. Kumar ◽  
B. Bhattacharya ◽  
T. Agarwal ◽  
S. Chakkaravarthi

The study was envisaged to examine the quality of frying oil used by street food vendors for two of the most popular food items viz. Samosa and Jalebi in India. Changes in the quality of frying oil were analysed by analysing the total polar material (TPM) content in the oil using an oil tester and Attenuated total reflectance–Fourier transform infrared (ATR-FTIR) spectroscopy. Total 143 oil samples were collected at different frying times, i.e. 0, 2 and 4 h from five different Samosa and Jalebi vendors. In both the fried food oil samples, TPM content increased with increasing frying time. The TPM content in the 4 h fried oil samples of Jalebi was significantly (p< 0.001) higher than the samosa fried oil. Partial Least Square Regression (PLS) model based on the 1st derivative FTIR spectra exhibited good prediction capability for TPM values with a high regression coefficient (R2 ≥ 0.99) and low root mean square error (RMSE).


2017 ◽  
Vol 7 (2) ◽  
pp. 61
Author(s):  
Ummi Kaltsum ◽  
Affandi Faisal Kurniawan ◽  
P Priyono ◽  
Iis Nurhasanah

Mutu jelantah lebih rendah dibandingkan minyak goreng baru, karena mengandung produk-produk degradasi (radikal bebas, molekul lemak jenuh, total polar material, dan polimer). Jumlah produk degradasi dalam jelantah dapat diturunkan menggunakan lapisan tipis TiO2 yang memiliki sifat fotokatalis. Lapisan tipis TiO2 dibuat dengan mencampurkan TTiP dan AcAc dengan perbandingan molar 1:2. Campuran dideposisikan di atas substrat kaca dengan metode spray coating pada suhu 450 oC. Sebagian lapisan tipis yang sudah di-coating kemudian dianil pada suhu 500 oC selama 2 jam. Proses penurunan produk degradasi dalam minyak goreng dilakukan menggunakan lapisan tipis TiO2 tanpa anil dan lapisan tipis TiO2 yang dianil secara terpisah melalui proses fotokatalis. Proses fotokatalis dilakukan menggunakan matahari selama 5 jam. Keberadaan produk-produk degradasi dalam minyak goreng dikaji berdasarkan perubahan sudut polarisasi cahaya minyak goreng. Besarnya perubahan sudut polarisasi minyak goreng sebanding dengan jumlah produk degradasi. Tidak ada perbedaan yang signifikan pada kedua jenis lapisan tipis TiO2 dalam menurunkan produk degradasi. Setelah proses fotokatalis selama 5 jam, kedua jenis lapisan tipis TiO2 berhasil menurunkan jumlah produk degradasi yang sama yaitu hingga 71,43%. Hasil tersebut menunjukkan kedua jenis lapisan tipis TiO2 mampu mengurangi produk degradasi dalam jelantah.


Processes ◽  
2021 ◽  
Vol 9 (3) ◽  
pp. 529
Author(s):  
Bojan Antonic ◽  
Dani Dordevic ◽  
Simona Jancikova ◽  
Bohuslava Tremlova ◽  
Marcela Nejezchlebova ◽  
...  

The study aimed to analyze the possibility of waste frying oil utilization in home-made soap production. Soaps were made from unheated and fried rapeseed, sunflower and palm oils that had total polar material (TPM) values up to 24%. Physicochemical and microbial analyses were performed on produced samples to check their quality. The hardness increased with the degradation level of rapeseed and palm oils, and opposite findings were obtained for sunflower-made soaps. The highest malondialdehyde (MDA) contents were recorded for sunflower oil-made samples, with the maximum of 6.61 µg/g, and the lowest for the palm oil-made samples, with the maximum of 0.94 µg/g. The antimicrobial assessment showed no significant (p > 0.05) differences between control soap samples and soaps made of oils with the highest TPM value. Gram-positive bacteria (methicillin-resistant Staphylococcus aureus: MRSA) were the most sensitive chosen microorganisms, compared to Gram-negative bacteria and yeasts. The obtained results did not show exact differences between experimentally produced soap samples from fried or not fried oils; these findings highlight the potential of home-made soap production from this byproduct.


2006 ◽  
Vol 76 (4) ◽  
pp. 230-237 ◽  
Author(s):  
Sanchez-Muniz

Diets of developed countries contain substantial quantities of fat subjected to different processing and heat treatments. Heating in the presence of air produces oxidative and thermal degradations in the unsaturated acyl groups of triacylglycerols and in other unsaturated compounds present in the oils and fats. These changes modify the nutritional properties of culinary fat and lead to the formation of many oxidized and polymerized compounds that present higher polarity than that of the original triacylglycerols. Some aspects of lipid peroxidation that occur in heated and used frying oils will be briefly presented and discussed. This paper will focus on appropriate methodology for the assessment of fat alteration (e.g. chromatography) and the point at which any oil used for frying should be discarded. Polar material (PM) and triacylglycerol oligomer content (TOC) determinations constitute the basis of legislation for oil discarding in some European countries; we will try to open some debate on whether PM or TOC is preferred for oil discarding assessment. Correct frying performance helps to lengthen oil frying-life and to decrease the alteration content in the fried food. Because many factors are present in the culinary and industrial frying, the effect of the process itself and that of the food and the type of oil used will be reviewed. The present report analyses and describes a wide variety of topics related to frying performance, and their nutritional implications with a special focus on the behavior during frying of most consumed oils in Mediterranean countries.


Author(s):  
M.T. Otten ◽  
P.R. Buseck

ALCHEMI (Atom Location by CHannelling-Enhanced Microanalysis) is a TEM technique for determining site occupancies in single crystals. The method uses the channelling of incident electrons along specific crystallographic planes. This channelling results in enhanced x-ray emission from the atoms on those planes, thereby providing the required site-occupancy information. ALCHEMI has been applied with success to spinel, olivine and feldspar. For the garnets, which form a large group of important minerals and synthetic compounds, the channelling effect is weaker, and significant results are more difficult to obtain. It was found, however, that the channelling effect is pronounced for low-index zone-axis orientations, yielding a method for assessing site occupancies that is rapid and easy to perform.


Author(s):  
Stuart McKernan ◽  
C. Barry Carter

The determination of the absolute polarity of a polar material is often crucial to the understanding of the defects which occur in such materials. Several methods exist by which this determination may be performed. In bulk, single-domain specimens, macroscopic techniques may be used, such as the different etching behavior, using the appropriate etchant, of surfaces with opposite polarity. X-ray measurements under conditions where Friedel’s law (which means that the intensity of reflections from planes of opposite polarity are indistinguishable) breaks down can also be used to determine the absolute polarity of bulk, single-domain specimens. On the microscopic scale, and particularly where antiphase boundaries (APBs), which separate regions of opposite polarity exist, electron microscopic techniques must be employed. Two techniques are commonly practised; the first [1], involves the dynamical interaction of hoLz lines which interfere constructively or destructively with the zero order reflection, depending on the crystal polarity. The crystal polarity can therefore be directly deduced from the relative intensity of these interactions.


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