This study focuses on the evaluation of official methods for determining frying oil quality with the new spectrophotometric method. The performance of these methods was examined by usage intermittent deep fat frying of potato chips in sunflower oil for 40 hr. at five consecutive days (8 hr., daily). Chemical analysis is the most reliable way to measure decomposition compounds in frying oil. With the prolonged frying time the amount of total polar compounds (TPCs) rises steadily. It has been suggested that the determination of TPCs is the most reliable method for the measurement of oil deterioration during deep frying processes. Beside, other oil quality indices during 40 hr. of intermittent deep fat frying were analyzed by the official methods and/or by rapidly spectrophotometric absorbance methods. Principal component analysis and linear regression analysis were used in order to assess the obtained results. The results were used to calibrate this spectrophotometric absorbance method. There was a strong correlation (r = 0.999) between quick spectrophotometric absorbance values and TPCs content in the same set of oil samples. The equation for conversion of the spectrophotometric absorbance values to TPCs content is: Y =-57.0083 + 2.64X + 0.049 X 2. Consequently, spectrophotometric absorbance method was developed to assess deep fat frying oil quality. This study was conducted to examine the relationship of TPCs contents determined by spectrophotometric method with physical, chemical indices and sensory evaluation. TPCs content was found to be correlated with refractive index (r = 0.950), viscosity (r = 0.989), colour (r = 0.993), acid value (r-0.899), iodine number (r = 0.947), P-anisidine value (r = 0.987), TBA test (r = 0.875), oxidized fatty acids (OFAs) (r = 0.975). Also, TPCs content was correlated with flavour (r-0.752), greasiness (r-0.917), crispy texture (r =-0.559) and overall acceptability (r =-0.649).These results showed that the new spectrophotometric absorbance method of frying oil is a good, rapid, simple, convenient and reliable indicator during deep fat frying of sunflower oil tested.

This study evaluates the effect of supplementation with Moringa leaves powder (MLP) at the concentrations of 0.25% and 0.50% (w/v) as additional sources of prebiotics to produce healthier fermented quinoa products. The biological experiment was used to study the influence of feeding with these fermented quinoa products on the blood biochemical parameters in experimental rats. The results indicated that selected probiotics, including Lactobacillus plantaram ATCC 14917 and Lactobacillus delbrueckii subsp. bulgaricus EMCC 11102 showed good tolerances to high acidity (pH = 2 or pH = 3), bile salts (0.3% w/v) and NaCl (7.5% w/v) and exhibited notable sensitivity against many antibiotics. Moreover, quinoa products supplemented with MLP at a concentration of 0.50% and fermented by both probiotics exhibited the highest counts of probiotic bacteria (9.32 and 9.12 log cfu/g, respectively) and showed more survival of probiotics than quinoa fermented without MLP (p > 0.05) during storage period. Also, the adding of MLP at both levels increased antioxidant activity and total phenolic contents of fermented quinoa by both probiotics, and the highest level exhibited highest values. Interestingly, fermented quinoa containing higher concentration of MLP showed the higher activity in improving serum lipid profile of experimental rats.

Fermentation of quinoa by probiotics provides higher nutritional value and can be considered as a significant source of bioactive compounds and alive probiotics for the human body. Moringa leaves powder (MLP) at the levels of 0.25 and 0.50% were used as an additional prebiotic source to supply quinoa fermentation by Lactobacillus plantaram ATCC 14917 and Lactobacillus delbrueckii ssp. Bulgaricus EMCC 11102 and produce healthier quinoa products. The results indicated that supplementation of fermented quinoa products with MLP at bath levels increased its contents of free phenolics and water extractable arabinoxylans as well as enhanced its antioxidant activity and phytate degradation. Fermented quinoa products with 0.50% MLP showed better chemical properties than fermented quinoa products with 0.25% MLP. Furthermore, supplementation of fermented quinoa products with MLP (0.50%) displayed positive effects on blood glucose levels of the experimental rats. Further studies are required on the test of more kinds of probiotics with different concentration of MLP in quinoa fermentation in the future.

No abstract

Fiber enrichment of carob pods powder (CPP), sugar and fat replacement are third effective ways in the creation of a healthy diet. This work was conducted to evaluate the effect of partial fat/or sugar replaced cupcakes made from wheat flour WF (72% ext.) by different levels (20, 40, 60, 80 and 100%) of carob pods powder CPP. Comparing between WF and CPP, data revealed that CPP had higher content of fat (2.10%), ash (3.33%), crude fiber (18.58%), phenolic compounds (1800 mg GAE / 100 g), antioxidant activity (17.2%), K (848 mg/100 g), Ca (212.540 mg / 100g), and Fe (38.15 mg/100g). Evaluating cupcakes chemically, physically, rheologically and organoleptically. Chemical composition of fat and/or sugar replaced cupcakes were high in ash content, crude fiber, phenolic compounds and antioxidant activity, while it was low in nitrogen free extract (NFE), protein and caloric values. Moreover, Fe, Zn, Ca and Mg contents were significantly improved. Results indicated that using CPP as a fat or sugar replacers, gradually increased the sensory characteristics with increasing the levels for up to 60% of replacing level, and still acceptable until the highest level of replacing. Findings showed that additives 40 or 60% of CPP as a fat or sugar replacer respectively, increased the water absorption, dough development time, degree of weakening and extensibility, Meanwhile, decreased stability time, resistance to extension, energy and proportional number. Noteworthy, lead to reduce the caloric value and staling case. It could be concluded that the supplementation WF with40 or 60% of CPP used as a fat and /or sugar replacer for cupcakes making to enhance the nutritional values, sensory and rheological properties without adverse effects on the physical and sensory attributes.

This study was conducted to reduce the simulated chemical changes of sunflower oil during intermittent heating and / or frying model technique, and to improve the thermal stability of oil, and to study the effects on acrylamide formation level by some additives such as oleoresin thyme (OTE) and rosemary extracts (ORE) at different levels (100, 200, 300, 400, 500 and 600 mg-1 L oil), in comparison to standard oil sample (without addition of extracts) and / or (with addition 200 mg-1 L oil of BHA), and the chemical changes were correlated with acrylamide content aiming at establishing prediction models for estimating acrylamide content; during intermittent heating and / or frying model technique of potato chips at 175 o C for 24 hrs. at three consecutive days (8 hrs. daily). The results could be concluded that addition of OTE and/ or ORE to sunflower oil kept its characteristics from being deteriorated. During the simulated heating and / or frying model technique, the OTE or ORE act as an antioxidant taking part in the chain radical oxidation, as well as simultaneously inhibiting the thermal processes occurring in oil. Induction period (IP) was decreasedby increasing the thermal treatment period. Moreover, the addition of OTE and/ or ORE up to 400 mg-1 L oil increase IP before thermal treatment then slows down the decreasing of the IP in comparison to the control samples, and TPCs, TBA and acrylamide content of control oil samples were significantly lower than that of the oil samples treated with OTE and/or ORE.Under the conditions simulated heating and / or frying model technique, the OTE inhibits oxidative processes more strongly than ORE or BHA. The results demonstrate that the heating model technique causes a slower increase in acrylamide content during treatment at 175 o C in comparison to frying model technique, (39.18 %) under heating model technique.While, ORE reduced the acrylamide ranged by 25.54% and 27.48% fewer than500 mg-1 L oil during frying and heating model technique respectively. The correlation coefficient between acrylamide level and frying time was very high (r = 0.986) for control sample, and an equation for prediction the acrylamide was γ =-190.9 + 0.116 X. The correlation coefficient between acrylamide level and TPCs content was very high (r = 0.994) for control sample, while the correlation coefficient between acrylamide level and TPCs (r =-0.621) for oil treated with OTE at 400 mg-1 L during frying, and (r = 0.732) during heating model system.During the progressive frying of the potato chips, the sensory panel could distinguish a difference in flavor between the fried potato chips in sunflower oil with and without OTE or ORE. Panelists preferred the chips fried in oil treated with OTE or ORE.

Nowadays, consumer trends towards healthier and low fat products have a significant impact on the deep fat frying industry. The objective of this study was to design a modified deep fat fryer (MDF) to have a smaller surface area relative to height, with made a steam blanketing over the fryer. Different levels of water injection flow rates have been used (0.1, 0.2 and 0.3 ml/20 min. per 1 liter of tested oil), compared with conventional fryers (CDF). Frying was conducted at 170 ± 10 °C into sunflower oil using CDF (H√A = 0.24) and MDF (H√A = 0.8) in batch 8 min. 16 batches every day (eight hrs. /day)for up to 40 hrs (Consecutive five days). The modification was intended to related oil deterioration. Water injection had a dual effect. In comparison with CDF, water injection increased the acidity (expressed as oleic acid) from 0.34 % to 0.97 %, after 40 hrs at 170 ± 10 °C of deep fat frying, and a contrarily, the protective role was observed in all the other quality indices. Significant reductions in TBA values (from 8.9 to 4.81mg malonaldehyde/liter of tested oil), P-anisidine values (from 35.6 to 12.9), TPC contents (from 34.5% to 18.64%), conjugated diene (232 nm) (from 8 to 5.59) and conjugated triene (268 nm) (from 1.9 to 1.33) were recorded in sunflower oil compared with CDF. These quality indices of sunflower oil developed dramatically in the first level of water injection flow rate. Consequently, the first level of water injection had the highest (P≥0.05) inhibitory effect compared with the other levels of water injection. Fatty acid composition of fried oil properties during deep frying CDF and MDF designs were determined. There were significant differences (P≥0.05) of fatty acids composition between the fried oil induces during using of CDF and MDF designs. Total unsaturated fatty acid at MDF design gave the highest values. Also, organoleptic evaluation of fried potato chips by CDF and MDF were evaluated by panelists. Fried potato chips during the first level of water injection flow rate had the highest (P≥0.05) flavor (4), crisp (4.5), greasiness (4.6), and overall acceptability (4.8), compared with fried potato chips during other levels of water injection flow rates and with CDF. Findings suggest that determination of the oil quality indices are good makers of sensory evaluation during deep fat frying. Results indicated the changes in moisture content, oil uptake and shrinkage percentages of potato chips at different levels of water injection compared the control samples. The negative correlation coefficient between oil uptake and moisture content was high (r = -0.915) and linear regression equation for prediction the oil uptake y = 34.1064 -2.0291X. Also, results suggest that during deep fat frying by MDF design may reduce the thermal deterioration of sunflower oil. Water injection can be applied as a simple method to improve oil quality during deep fat frying.

Fermentation of oat by probiotic bacteria enhances its nutritional value and can be considered as a significant source of bioactive compounds and alive probiotics for the human body. Moringa leaves powder (MLP) at the levels of 0.25 and 0.50% were used as an additional prebiotic source to supply the oat fermentation by Lactobacillus plantaram ATCC 14917 and Lactobacillus delbrueckii ssp. Bulgaricus EMCC 11102 and produce healthier oat products. The results indicated that oat products supplemented with MLP at a level of 0.50% and fermented by L. plantaram ATCC 14917 and L. delbrueckii ssp. Bulgaricus EMCC 11102 showed the highest probiotic counts (10.61 and 10.11 log cfu/g, respectively) and exhibited more survival of probiotics than oat fermented products without MLP (p > 0.05) throughout the storage period. Moreover, fermented oat products supplemented with MLP at the same level showed higher activity of reducing both fasting and postprandial blood glucose levels in the experimental rats. These products may have a potential role as effective vehicles for probiotics and control of type 2 diabetes mellitus (DM) in the future.