Effect of Frying Temperature and Time on Thermophysical Properties and Quality Attributes of Deep-Fat Fried Plantain (Dodo)

This study investigated the effect of the processing conditions (frying temperature and time) on the thermophysical properties and product quality attributes of deep-fat fried plantain (dodo). The plantain were deep-fried at various frying temperatures (150-190 °C) and time intervals (120-240 sec). The thermophysical properties determined include specific heat, thermal conductivity, thermal diffusivity and density. The product quality attributes were moisture content, oil content and colour. The specific heat, thermal conductivity, thermal diffusivity and density of the deep-fat fried plantain ranged from 2.68 to 2.33 kJ/kgK, 0.37 to 0.33 W/mK, 1.12 to 1.36 x10-7 m2/s and 1049.50 to 1257.00 kg/m3, respectively. The quality attributes of dodo varied from 0.24 to 0.65 abs, 30.37 to 43.40% and 9.96 to 14.25% for colour, It was observed that the specific heat, thermal conductivity, thermal diffusivity and moisture content of the deep-fat fried plantain were significantly reduced as frying temperature and time increased. The colour and fat content of dodo were found to increase with increased temperature and time of frying. Outcome of the study resulted in the development of dodo with high acceptable quality characteristics. Therefore, generated data will be useful in choice of processing conditions for plantain and development of fryer.

Stability of Bioactive Compounds in Olive-Pomace Oil at Frying Temperature and Incorporation into Fried Foods

The stability of minor bioactive compounds in olive-pomace oils (OPOs) was evaluated at frying temperature under the conditions of a thermoxidation test. Bioactive compounds analyzed included squalene, tocopherols, sterols, triterpenic acids and alcohols, and aliphatic alcohols. In order to determine the amount of OPO bioactive compounds incorporated into foods after frying, three different kinds of frozen products were selected, i.e., pre-fried potatoes (French fries), pre-fried battered chicken nuggets, and chicken croquettes (breaded patties), and were used in discontinuous frying experiments. Results obtained in both the thermoxidation and frying studies showed high stability of triterpenic alcohols (erythrodiol and uvaol), oleanolic acid, and aliphatic alcohols, naturally present in OPOs. In all fried foods, the content of lipids increased after frying, as expected, although the extent of absorption of OPOs into fried foods and the exchange with food lipids depended on the food characteristics. Overall, frying with OPOs improved the nutritional properties of all products tested by increasing the level of oleic acid and by the incorporation of squalene, triterpenic acids and alcohols, and aliphatic alcohols, in significant quantities.

Optimization of the Frying Temperature and Time for Preparation of Healthy Falafel Using Air Frying Technology

Air-frying is an innovative technique for food frying that uses hot air circulation to prepare healthy products. The objectives of this study were to establish simplified models to reflect the efficacy of the air frying process at varying temperatures and times on the quality attributes of falafel, and to optimize the frying conditions for producing air-fried falafel. Moisture content, color, fat content, hardness, and sensory evaluation of the fried falafel were analyzed under varied temperatures (140 °C, 170 °C, and 200 °C) and time periods (5 min, 10 min, and 15 min). Statistical analysis was then applied to obtain the best fit model that can describe the properties of fried falafel. Results indicated that moisture content, fat content, and L*-value of air-fried falafel were adversely related to the frying temperature and time, but the hardness and ΔE of fried falafel were increased as the frying temperature and time increased. Moreover, an increase followed by a decrease was shown for the appearance, aroma, crispness, taste, and overall preference scores with the increase in frying temperature and time. The regression analysis showed that the proposed models could be properly used for predicting the properties of the fried falafel. In addition, the overlaid plots resulted in the optimum frying temperature of 178.8 °C and time of 11.1 min. Interestingly, the fat content of the air-fried falafel reduced by 45% at optimal frying conditions compared with that for the deep-fat fried one at 180 °C for 7 min (control). In comparison, the air-fried falafel was lower in fat content, higher in hardness with more acceptable appearance and crispness scores than deep-fat fried falafel. Such information could be beneficial to the manufacturers of the falafel to produce an optimal and healthy product.

The Effect of Vacuum Deep Frying Technology and Raphanus sativus on the Quality of Surimi Cubes

This study uses a response surface methodology to optimize the vacuum deep frying process of surimi cubes. The effects of vacuum deep frying temperature, frying time, and thickness on the hardness and color difference of surimi cubes with Raphanus sativus were studied. Further, the manuscript explored the quality changes of surimi cubes under different frying processes (vacuum deep frying, atmospheric deep frying, and shallow frying). Moreover, the Chinese Min-Cantonese cuisine-Raphanus sativus was utilized as auxiliary raw material to change the hardness and reduce the oil content. The optimal parameters of response surface methodology determined were: vacuum deep frying temperature 130 °C, frying time 900 s, and thickness 0.75 cm. Additionally, under this process condition, the hardness of the surimi chunks was 2015 ± 48.17 g, and the color difference was 23.27 ± 1.86. Surimi cubes without Raphanus sativus have superior elasticity and low hardness, and surimi cubes with Raphanus sativus have little color difference and high chewability. After the vacuum deep frying process, there was a high protein content and superior crispness. Shallow frying and adding Raphanus sativus effectively reduced the product’s oil content. Therefore, Raphanus sativus is suitable as a potential nutritional supplement to broaden its application in fried surimi foods.

Frying Time and Temperature Conditions’ Influences on Physicochemical, Texture, and Sensorial Quality Parameters of Barley-Soybean Chips

Demand for innovative healthy snacks that achieve consumer satisfaction represents increased interest for competitive food producers. The aim of this work was the assessment of physicochemical and sensory quality of barley-soybean chips involving legume protein flours by studying the effects of different substitution levels (10, 20, and 30%) of defatted soybean (DSB) flour, frying temperatures (150, 170, and 190°C), and frying times (60, 90, and 120 sec). The chips’ moisture content was significantly decreased with increased frying temperature and time. The moisture content (1.40%) was achieved at 10% DSB fried at 190°C for 120 sec. The least absorbed oil (29.25%) was achieved at the least substitution percentage (10% DSB), the least frying temperature (150°C), and the least frying time (60 sec). These results were reflected on sensorial parameters that revealed that the most preferred chips were barley-soybean chips with 10% DSB fried at 150 and 170°C. The amylose content was increased by 33.80% in chips substituted with 30% DSB, while it was decreased to 27.16% in chips substituted with 10% DSB, and vice versa for the amylopectin content. TPA revealed that DSB substitution levels were directly proportional with hardness and inversely proportional with elasticity and adhesiveness. From obtained results, substitution levels with 10% DSB fried at 150°C are recommended. These findings encourage the production of innovative enhanced snacks involving legume protein while maintaining consumer satisfaction.

Effects of Food Types, Frying Frequency, and Frying Temperature on 3-Monochloropropane-1,2-diol Esters and Glycidyl Esters Content in Palm Oil during Frying

3-Monochloropropanediol esters (3-MCPDE) and glycidyl esters (GE) have high toxicity and have drawn global attention because of their widespread occurrence in refined oils and oil-based foods. In this study, the effects of food type (potato chips and chicken breasts), frying frequency, and frying temperature on the formation of 3-MCPDE and GE in palm oil (PO) were investigated. The results showed that 3-MCPDE was formed easier in chicken breasts than potato chips. The GE content decreased in PO after it was used for frying potato chips and chicken breasts with or without NaCl. Frying frequency was an influencing factor in the formation of 3-MCPDE and the decrease in GE in PO. Frying temperature was positively correlated with GE degradation, while it had a bidirectional effect on the formation of 3-MCPDE. The formation kinetic equations indicated that 3-MCPDE and GE followed zero-order reactions in PO. The estimated activation energy (Ea) of 1,2-bis-palmitoyl-3-chloropropanediol (Pa-Pa, 41.05 kJ/mol) was lower than those of the other three types of 3-MCPDE; this is the first theoretical explanation for why PO contains more 3-MCPD than other edible oils. Among GEs, glycidyl oleate (Li-GE) was degraded more readily than other GEs.

Frying Conditions, Methyl Cellulose, and K-Carrageenan Edible Coatings: Useful Strategies to Reduce Oil Uptake in Fried Mushrooms

Despite being widely consumed and appreciated, fried food has the unhealthy characteristic of high final oil content. Therefore, alternatives to reduce the oil uptake of fried products are being researched. The aim of this study was to investigate the effect of 0.5% methyl cellulose and 0.5% kappa-carrageenan edible films, as well as different frying procedure parameters, such as oil temperatures (from 150 to 180 °C), and thickness of slices (from 2 to 6 mm) on the oil uptake of whole fried mushrooms and their parts. The results showed a lower final oil content when lower frying temperature and thicker slices are applied. Hydrocolloid suspensions of methyl cellulose and kappa-carrageenan, used as edible coatings, were effective at reducing moisture evaporation and, consequently, oil uptake independently of the hydrocolloid temperature. A reduction of 10–22% in the final oil content was achieved. Adjusting the frying parameters and the use of methyl cellulose or kappa-carrageenan as an edible coating were useful strategies to reduce the oil uptake in fried products.

Process optimization of chili flavor beef tallow and analysis of its volatile compounds by GC-IMS

With chili and liquid beef tallow as the main raw materials, the processing conditions of chili flavor beef tallow were explored. Gas chromatograpy-ion mobility spectrometry (GC-IMS) was used to determine the volatile compounds in chili flavor beef tallow. The capsaicin and dihydrocapsaicin in chili flavor beef tallow were determined by high performance liquid chromatography (HPLC). The optimum technological conditions were determined, and the index of chromatic aberration, cholesterol was also determined. Based on GC-IMS analysis, 102 kinds of volatile compounds were detected, and the sample III (the ratio of solid–liquid was 1:5, the frying temperature was 120 °C, and the frying time was 15 min) performed better than other samples. The preparation of chili beef tallow improves its antioxidant activity and makes its aroma more intense and more in line with the taste of Chinese people, which provides a theoretical and practical basis for the development of spice beef tallow in the future.