Formation of Alkylbenzenes and Tocochromanols Degradation in Sunflower Oil and in Fried Potatoes during Deep‐Frying and Pan‐Frying

Tenebrio molitor (T. molitor) (mealworm) larvae are one of the most promising insects for feed–food purposes. Mealworms are rich in several macro and micro nutritional elements and can be practically reared on side stream substrates. In this study, the effects of seven different cooking techniques were tested on the nutritional value of mealworms focusing the attention on protein digestibility, fatty acid (FA) profile, and oxidative status. Uncooked larvae (UC) were used as control and compared to two combinations of temperature/time in oven cooking (70°C for 30 min, OC70-30, 150°C for 10 min, OC150-10), two methods of frying (mealworms fried in sunflower oil as deep fry, DF, or pan fry, PF), microwaving (MW), boiling (in plastic bag under vacuum, BO), and steaming (ST). Proximate composition, in vitro digestibility (gastric and duodenal), FA profile, and oxidative status (tocopherol and tocotrienol, carbonyl, and lipid oxidation) were then tested. Cooking technique affected all the tested parameters. As expected, cooking affected proximate composition in relation to the method applied (dry matter increased after oven cooking and frying; lipids increased by frying). In vitro digestion revealed the highest value for the OC70-30 method, followed by UC and ST. Deep frying revealed the worst digestibility percentage. FA profile was deeply affected by the cooking technique, with general decrease in SFA and MUFA. The highest modifications in FA profile were revealed in ST larvae with an increased percentage of linoleic acid linked to the lowering of SFA and MUFA contents. Furthermore, deep frying larvae in sunflower oil increased the relative abundance of PUFAs. Tocols values were higher in DF and MW groups than PF (about 6-fold more) and all other groups (7-fold more). Carbonyls increased with oven cooking (OC150-10 and OC70-30), whereas the values were lower with frying and similar to ST and UC. Lipid oxidation was highest as well in OC150-10 but similar to frying methods (DF and PF). Based on the obtained results, it can be concluded that mealworm larvae surely meet human nutritional requirements, but the cooking method must be carefully chosen to maintain a high nutritional value.

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Quality parameters of different oils and fried foods after repeated deep-fat frying

Meso ◽

10.31727/m.22.6.3 ◽

2020 ◽

Vol 22 (6) ◽

pp. 460-474

Author(s):

Tomaž Polak ◽

Lea Demšar ◽

Nežka Lazar ◽

Iva Zahija ◽

Mateja Lušnic Polak

Keyword(s):

Fatty Acid Composition ◽

Fatty Acid ◽

Acid Composition ◽

Sunflower Oil ◽

Peroxide Number ◽

Deep Frying ◽

Deep Fat Frying ◽

Chicken Nuggets ◽

Frying Process ◽

Fried Foods

The aim of present study was to investigate the quality, stability and suitability of different frying oils (coconut, palm, frying mix, rapeseed and sunflower oil), the quality and stability of breaded and fried foods (chicken nuggets) and the applicability and suitability of certain parameters (fat absorption, acid number, peroxide number and thiobarbituric acid (TBA) number, fatty acid composition and acrylamide content) as well as sensory attributes to control the repeated deep-(fat) frying process. Three repeated deep-frying processes affected the hydrolytic and oxidation stability (increase in the peroxide number and TBA number), the sensory properties (darkening of the oil colour, occurrence of odd smell and aroma as well as rancidity in oils) and the fatty acid composition of oil and fried chicken nuggets, and the acrylamide content in the nuggets (from the second deep-frying process onwards). All oils used in study were suitable for deep-frying; in terms of stability, coconut oil (followed by sunflower, palm, frying mix and rapeseed oil) was most suitable; in terms of fatty acid composition, the frying mix, rapeseed and sunflower oil were most suitable; and in terms of acrylamide formation and sensory quality, coconut and palm oil were most suitable.

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Carvacrol methyl ether, a compound from the essential oil of Gardenia jasminoides fruits, exhibits antioxidant effects in the deep-frying of Chinese Youmotou using sunflower oil

LWT ◽

10.1016/j.lwt.2020.109502 ◽

2020 ◽

Vol 128 ◽

pp. 109502

Author(s):

Dongying Wang ◽

Qing Wang ◽

Shuchang Li ◽

Yuanxin Xu ◽

Xuede Wang ◽

...

Keyword(s):

Essential Oil ◽

Methyl Ether ◽

Sunflower Oil ◽

Deep Frying ◽

Gardenia Jasminoides ◽

Antioxidant Effects

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Phytosterols in frying oils: evaluation of their absorption in pre-fried potatoes and determination of their destruction kinetics after repeated deep and pan frying

Procedia Food Science ◽

10.1016/j.profoo.2011.09.092 ◽

2011 ◽

Vol 1 ◽

pp. 608-615 ◽

Cited By ~ 7

Author(s):

Panagiotis E. Igoumenidis ◽

Maria A. Konstanta ◽

Fotini N. Salta ◽

Vaios T. Karathanos

Keyword(s):

Frying Oils ◽

Destruction Kinetics ◽

Pan Frying ◽

Fried Potatoes

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Fatty Acid Changes in High Oleic Acid Sunflower Oil during Successive Deep-Fat Fryings of Frozen Foods

Food Science and Technology International ◽

10.1106/197r-7yne-8qnh-715y ◽

2001 ◽

Vol 7 (4) ◽

pp. 317-328 ◽

Cited By ~ 16

Author(s):

C. Cuesta ◽

A. Romero ◽

F. J. Sánchez-Muniz

Keyword(s):

Fatty Acids ◽

Oleic Acid ◽

Fatty Acid ◽

Sunflower Oil ◽

Frying Oil ◽

Oleic Acid Content ◽

High Oleic Acid ◽

Frozen Foods ◽

High Oleic ◽

Fried Potatoes

High oleic acid sunflower oil (HOSO) is a monounsaturated oil that is being extensively used in frying. The level of total altered fatty acids and the fatty acid pattern of a fryer oil was used to evaluate the alteration of a HOSO used 20 times to fry various frozen foods with frequent replenishment (FR) or without replenishment (NR) with fresh oil during the frying. In addition, the levels of total altered fatty acids and the fatty acid composition of the fat extracted from the fried potatoes after numerous fryings were determined and compared to those of the corresponding fryer oils. Altered fatty acids increased linearly through 20 fryings within FR and NR in the frying oil and also in the fat extracted. Although differences were not quantitatively relevant, changes tended to be higher in the extracted fat, and in the NR modality as a consequence of oil renovation and fat exchange between the frying oil and the potatoes. The decrease in the oleic acid content in the oil was more pronounced ( p< 0.001) in NR than in FR method, and more (at least p< 0.01) in the oils than in the corresponding extracted fats. Nevertheless, other fatty acids remained quite stable and similar or increased during frying, by both methods. These results suggest that total fatty acid alteration measure is a useful tool for frying assessments, and that they must be related not only to the degradation of unsaturated fatty acids but also to migrations of some fatty acids from the frozen prefried foods to the fryer oil as revealed by composition of the fat extracted from the fried potatoes.

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