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Lard is a preferred frying fat in the Hungarian culinary routine. Our study aimed at measuring conventional fat quality indices and performing NIR-based calibrations of those indices, during prolonged heating. Lard was heated for 4 days at 8 different temperatures (160, 170, 175, 180, 185, 190, 200 and 230 °C) for 8 h a day (n=32+1, i.e. the original sample). Acid value (AV) and carbonyl value (CON) increased in parallel with the duration of heating and heating intensity. Peroxide value (PV) increased in the first 8 h, and decreased back during further treatment. p -Anisidine value (pAV) increased at each heating temperature below 200 °C, while temperatures above 200 °C decreased it. NIR analysis (NIRSystems 6500) was performed on original samples in transflectance mode (400–2500 nm wavelength range, 0.1 mm layer thickness, aluminium-plated reflector). Treatment characteristics (temperature, heat-sum, sampling event) could be estimated effectively. Calibration for AV was robust: R 2 =0.927; 1-VR=0.786. Weak relationship was found for PV (R 2 =0.48) and CON (R 2 =0.109). For pAV, good calibration was gained, expressly below 200 °C, in the 2000–2500 nm wavelength interval (R 2 =0.912; 1-VR=0.772). Based on calibration and cross-validation results, NIR technique may be a rapid, solvent-free alternative for the estimation of acid value and p -anisidine value of lard below 200 °C.

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Investigation of the complex thermal behavior of fats

Combined DSC and X-ray diffraction techniques

Journal of Thermal Analysis and Calorimetry
Authors: G. Keller, F. Lavigne, C. Loisel, M. Ollivon, and C. Bourgaux

The thermal behavior of three ural fats (displaying very different composition), cocoa butter (CB)2, lard, and a stearin obtained from anhydrous milk-fat (AMF) fractionation, were studied by both DSC and X-ray diffraction as a function of temperature (XRDT). To perform temperature explorations between −30‡C and +80‡C, at rates identical to those used for DSC and ranging from 0.1 K min−1 to 10 K min−1, a new set of X-ray sample-holders, temperature-controlled by Peltier effect, has been developed. It is shown that the three more stable polymorphic forms of CB were easily characterized by either X-ray diffraction or DSC, and existence of two Β-3L forms was confirmed. On the contrary, the more complex polymorphism of lard and AMF required combined examination by DSC and XRDT and the brightness of the synchrotron source for studies at the highest heating rates. Quantitative analysis of the long spacings of XRDT recordings is invaluable for interpretation of thermal events. For instance, it was found that the simultaneous formation of two polymorphic forms, of apparent long spacing of 34 and 42 å, at the onset of lard crystallization might explain the difficulty of its fractionation.

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Campos, R., Narine, S.S. & Marangoni, A.G. (2010): Effect of cooling rate on the structure and mechanical properties of milk fat and lard. Fd Res. Int., 3, 971–981. Marangoni A

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De Leonardis, A. , Macciola, V. , Lembo, G. , Aretini, A. & Nag, A. (2007a): Studies on oxidative stabilisation of lard by natural antioxidants recovered from olive-oil mill wastewater. Fd Chem. , 100 , 998

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sunflower oil obtained from Carnia hybrid and pork lard were the matrix used for antioxidants incorporation. Materials and methods Plant material Herbarium information of the seven plant species which are

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Acta Veterinaria Hungarica
Authors: József Szabó, Gergely Maróti, Norbert Solymosi, Emese Andrásofszky, Tamás Tuboly, András Bersényi, Geza Bruckner, and István Hullár

, the effects of specific macronutrients need further clarification. The aim of this study was to determine the special effects of the nutrients glucose, fructose, and lard replacing the starch content of the AIN-93G diet (control), at constant nutrient

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Development of rapid methods is often needed for the in-line process control of the proximate composition (e.g. fat or moisture content) of meat in the meat processing plants. This paper reports on the continuous wave nuclear magnetic resonance (CW-NMR) technique applied for determining fat content in fresh meat. The interfering moisture content in meat was removed by microwave drying and the dried residue was transferred quantitatively into the NMR-tubes. The total analysis time was about 35 min. Experiments were performed with pork (with a fat content from 1.7% to 21%), beef (with a fat content from 1.0% to 16.1%), lard (rendered pork fat) and tallow (rendered beef fat) samples and with their combinations: lard-tallow, lard-lean pork, tallow-lean beef and lard-tallow-lean beef-lean pork. The regression (prediction) equations (NMR-signal vs. fat content determined with the Soxhlet reference method) of pork and beef did not differ significantly. However, there was a noticeable difference between the regression lines of pure lard and pure tallow. Moreover, the latter ones differed from the regression equations of pork, beef and of the various meat-fat combinations. The variability of the fatty acid composition of the fat also seems to influence the stability of the calibration curves, because the sensitivity of the CW-NMR signal to the fatty acid composition interferes with the quantitative determination of fat content in meat.

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Healthy eating, chiefly the quantity and quality of dietary fats and oils, takes a prominent part in promoting the optimal health status and in preventing the development of chronic disorders, mainly cardiovascular diseases. In Hungary the consumption of lard (the characteristic fat in the Hungarian diet) has fallen by 30% since 1980, and that of edible oil (above all sunflower oil) has been almost triplicated since 1970. The total fat consumption remained unchanged. From the eighties and nineties the mortality of cerebrovascular diseases, atherosclerosis and acute myocardial infarction significantly decreased, that of hypertension remained unchanged. Although cardiovascular diseases have a number of aetiological factors, the change of dietary fats and oils may play a role in the improvement of mortality data.

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The aim of this study was to investigate the nutritional habits and lifestyle practice of elderly people living in their own home. Altogether 213 subjects (men over 65 years, women over 60 years), were recruited randomly from a primary care office in Budapest. Nearly 60% of people had three meals per day, but the number of meals increased during ageing. The most substantial meal was the lunch. Meals were prepared at home by 90% of the elderly. Lard for cooking was used by 44% of subjects. Additional use of salt was never mentioned by 18% of seniors only. Milk, dairy products, fish, fruits, fresh vegetables and vegetable dish were consumed far below the recommendations. All types of meat were radically decreased, especially beef compared to former Hungarian surveys and the data of the Hungarian Central Statistical Office. Almost one-third of the elderly took some kind of vitamins and/or mineral supplements. The average time spent with outdoor activity was only 12 h per week.In relation to non-infectious diseases connected with nutrition, the irregular consumption of food has to be underlined. The insufficient consumption of milk and dairy products may have an unfavourable effect on the bone status. Deficient consumption of fruits, vegetables and cereals may play a role in the development of cardiovascular diseases and certain types of tumours. The exaggerated salt intake has to be taken into account mainly in hypertension. The inadequate physical activity may be also responsible for decreased longevity of our population.

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A rapid and accurate direct injection enthalpimetric (DIE) method has been developed for the determination of the water content in some oils and fats of commercial interest. The method combines the DIE and the Karl Fischer Reagent procedures and is calibrated against real samples whose water content have been determined by a standard distillation method using toluene as the immiscible solvent. The reproducibility and precision are equivalent to those of the standard method for the water content of materials such as soya bean oil. The procedure is able to determine water contents in compounds such as lard, which cannot be determined by the Dean & Stark method. Once calibrated, the proposed method can be operated routinely by semi-skilled personnel. The main advantages of the method are those of time and the cost of analysis.

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