No abstract

The oxidative stability of 12 edible fats and oils was determined at three different temperatures (80, 100, and 120°C) using the Oxipres apparatus, and compared with their characteristics (peroxide value, fatty acid composition, antioxidant capacity determined by the DPPH method and tocopherol content). Using a simple correlation analysis, oleic acid content was found to correlate most strongly with the oxidative stability of the analysed fats and oils (p < 0.01). Highly reliable models (p < 0.00001), defined the induction period as a function of the oleic/linoleic acid ratio, antioxidant capacity and peroxide value, were obtained by multivariate linear regression analysis at each of the three temperatures. In additional experiment, the effect of temperature on the induction period of sunflower oil, pork lard and extra virgin olive oil was studied in detail within the temperature range of 80–130°C. It was found that the logarithm of the induction period decreased linearly with increasing temperature (p < 0.01). However, the induction period of the different fats and oils decreased with temperature to a varying degree, i.e., the ratio between the induction periods of these fats and oils was affected by the temperature. Practical applications: Analyses to determine the oxidative stability of fats and oils are frequently required by food manufacturers, who use this information for the quality control of raw materials and, in particular, the selection of suitable fats or oils for food production. However, only a relatively small number of analytical laboratories are able to determine and interpret results obtained for the oxidative stability of fats and oils. On the other hand, determination of the composition of edible fats and oils (fatty acid composition, tocopherol content and other parameters) are routinely performed analyses. The ability to predict the oxidative stability of fats and oils from these commonly determined parameters can assist the selection and quality control of suitable raw materials for food manufacturers. The oxidative stability of selected edible fats and oils is determined at different temperatures using the Oxipres apparatus, and compare with their characteristics. Highly reliable models defined the induction period as a function of the oleic/linoleic acid ratio, antioxidant capacity and peroxide value, are obtained by multivariate linear regression analysis at each of the three temperatures.

Sensory acceptability of the consumption of whole baked house crickets by assessors in the Czech Republic was investigated. The main aim was to observe attitudes to eating edible insects before and after their tasting and to assess the extent of the effect of prejudices. Hedonic evaluation of the overall acceptability of edible insects was carried out under laboratory conditions by trained assessors. Of the 98 panellists, 68 were willing to evaluate the sample visually and then by tasting. They showed statistically significant differences (P &lt; 0.0001) in overall pleasantness before tasting (40 ± 22%) and after tasting (61 ± 17%). No statistically significant differences between male and female assessors were observed, either before or after tasting. Women and younger assessors were slightly more open to entomophagy, but there were no statistically significant differences between males and females or between the two age categories (18–25 and 26–45 years of age) in the results. The preferred methods of culinary preparation of edible insects that the respondents would choose were baking, roasting and frying.<br /><br />

Inadequate culinary conditions used for preparation of baked meat can contribute to an increased oxysterol intake in the diet. Frozen storage did not stop oxysterol formation. The inhibition effect of marjoram on sterols oxidation was not confirmed. © 2017 Society of Chemical Industry.

Contemporary society is faced with the question how to ensure suffiecient nutrition (quantity and quality) for rapidly growing population. One solution can be consumption of edible insect, which can have very good nutritional value (dietary energy, protein, fatty acids, fibers, dietary minerals and vitamins composition). Some edible insects species, which contains a relatively large amount of fat, can have a potential to be a "good" (interesting, new) source of minor lipophilic compounds such as sterols (cholesterol and phytosterols) and tocopherols in our diet. For this reason, the objective of this work was to characterize the sterols and tocopherols composition of fat from larvae of edible insect Zophobas morio L. and Tenebrio mollitor L. Cholesterol and three phytosterols (campesterol, stigmasterol and β-sitosterol) were reliably identified and quantified after hot saponification and derivatization by GC-MS. Other steroid compounds, including 5,6-transcholecalciferol were identified only according to the NIST library. Cholesterol was the predominant sterol in all analysed samples. Both types of larvae also contained high amount of phytosterols. Different region of origin had a no significant impact on sterols composition, while the effect of beetle genus was crucial. Tocopherols were analysed by reverse phase HPLC coupled with amperometric detection. Tocopherols content in mealworm larvae was lower than content in edible oils, but important from the nutritional point of view. Change of tocopherols composition was not observed during the storage under different conditions. Larvae of edible insect can be a potential good dietary source of cholesterol, but also vitamin D3 isomers, phytosterols and tocopherols.