Formation of trans fatty acids in chicken legs during frying

The formation of trans fatty acids in chicken legs during frying in unhydrogenated and hydrogenated soybean oil was studied. Frying was conducted at 160°C, 180°C and 200°C for 15, 30, 45, 60 and 75 min, with the various cis and trans fatty acids being analyzed in unhydrogenated and hydrogenated soybean oil, as well as chicken leg meat and chicken leg skin, using a gas chromatography–mass spectrometry technique. Results showed that the amounts of most fatty acids decreased along with increasing frying temperature and frying time when fried in unhydrogenated or hydrogenated soybean oil. No trans fatty acids were formed in chicken leg meat fried in unhydrogenated or hydrogenated soybean oil. Instead, the formation of trans fatty acids was observed in chicken leg skin fried in hydrogenated soybean oil, probably because of oil absorption. A maximum level of trans fatty acids occurred 15 min after frying and then declined thereafter.     

Application of starch-albumen powder as breading material in fried foods: An optimization study

The potential of using starch-albumen powder (SAP) as solid coating powder for fried food application was studied. Egg albumen was mixed with 10–30% dried starch and dried at 40–60°C air velocity of 4.5 m/s to produce SAP. SAP was used to coat wet yam chips prior to frying at 180°C for 3 min. The drying temperature and starch content in SAP significantly affected the oil uptake and moisture of fried chips. The increased amount of albumen (or reduced starch) content significantly reduced oil uptake. The sensory attributes influenced the overall acceptability of the fried chips in the order of taste > flavor > texture > appearance. To minimize oil uptake and moisture content and maximize acceptability of the fried chips, SAP dried at temperature of 40°C with starch content of 11.3% should be used. The study further indicates the potential of using SAP as coating in some other food products.     

Effect of deep-fat frying on ascorbic acid,carotenoids and potassium contents of plantain cylinders

The influence of thermal treatment (frying of plantain) on the micronutrients ascorbic acid, potassium and carotenoids is evaluated. Cylinders (diameter 30 mm, thickness 10 mm) of plantain (Musa AAB ‘barraganete’) were fried at four thermal treatments (120–180°C and from 24 to 4 min) to obtain products with approximately the same water content (≈0.8±0.02 kg/kg¹) and fat content (≈0.15±0.06 kg/kg). The thermal study used the cook value and the mean cook value as indicators of the effect of several different treatment temperatures and times on quality. Deep-fat frying had no significant effect on carotenoid contents at any frying conditions, and on potassium content, except at 120°C and 24 min (loss?≤?11%). There was a significant, but not complete, loss (≤45%) of ascorbic acid. The process with the greatest effect was low temperature and long time (120°C/24 min), as observed for potassium and ascorbic acid. These results are in agreement with other studies that demonstrated short thermal treatments at high temperatures protect food nutritional quality, as shown by the cook value and the mean cook value. In our work, deep-fat frying of plantain preserved most of the micronutrient contents that were evaluated.     

Acrylamide in crisps: Effect of blanching studied on long-term stored potato clones

Acrylamide, a probable carcinogen, is formed via the Maillard reaction between reducing sugars and the amino acid asparagine during heating of carbohydrate-rich foods. Potatoes contain high levels of these precursors, and thus potato crisps can contain high levels of acrylamide. In this study, the effect of blanching on the concentration of precursors and acrylamide content was studied in three potato clones stored at 4 °C or 8 °C. After 6, 12 and 18 weeks of storage, potatoes were sliced and blanched for 3 min in water at 80 °C and deep-fat fried for 3 min at an initial frying temperature of 180 °C and a final frying temperature of 160 °C. Blanching reduced the acrylamide content by 51–73%. Interestingly, blanching affected the levels of the precursor sugars and asparagine, but not the acrylamide content to the same extent. The reduction of precursors was 17–66%. This may be due to restriction of the transport of precursors to the surface, as the availability of precursors for reactions is crucial for acrylamide formation. In conclusion, blanching was an efficient way to reduce acrylamide content in potato crisps, in addition to using potatoes low in asparagine and reducing sugars.     

Formation of trans fatty acids in chicken legs during frying

The formation of trans fatty acids in chicken legs during frying in unhydrogenated and hydrogenated soybean oil was studied. Frying was conducted at 160 degrees C, 180 degrees C and 200 degrees C for 15, 30, 45, 60 and 75 min, with the various cis and trans fatty acids being analyzed in unhydrogenated and hydrogenated soybean oil, as well as chicken leg meat and chicken leg skin, using a gas chromatography-mass spectrometry technique. Results showed that the amounts of most fatty acids decreased along with increasing frying temperature and frying time when fried in unhydrogenated or hydrogenated soybean oil. No trans fatty acids were formed in chicken leg meat fried in unhydrogenated or hydrogenated soybean oil. Instead, the formation of trans fatty acids was observed in chicken leg skin fried in hydrogenated soybean oil, probably because of oil absorption. A maximum level of trans fatty acids occurred 15 min after frying and then declined thereafter.     

Fluid replacement advice during work in fully encapsulated impermeable chemical protective suits

A major concern for responders to hazardous materials (HazMat) incidents is the heat strain that is caused by fully encapsulated impermeable chemical protective suits. In a research project, funded by the US Department of Defense, the thermal strain experienced when wearing these suits was studied. One particular area of interest was the fluid loss of responders during work in these suits as dehydration may be an additional health concern to the heat strain. 17 City of Raleigh firemen and 24 students were tested at two different labs. Subjects between the ages of 25 and 51 were used for human subject trials in a protocol approved by the local ethical committee. Six different Level A HazMat suits were evaluated in three climates: moderate (24°C, 50% RH, 20°C WBGT), warm-wet (32°C, 60% RH, 30°C WBGT), and hot-dry (45°C, 20% RH, 37°C WBGT, 200 W/m² radiant load) and at three walking speeds: 2.5 km/hr, 4 km/hr, and 5.5 km/hr. 4 km/hr was tested in all three climates and the other two walking speeds were tested in the moderate climate. Weight loss data was collected to determine fluid loss during these experiments. Working time ranged from as low as 20 min in the hot-dry condition to 60 min (the maximum) in the moderate climate, especially common at the lowest walking speed. The overall results from all experiments showed that fluid loss ranged from 0.2–2.2 L during these exposures, with the average fluid loss being 0.8 L, with 56% of the data between 0.5 L and 1 L of fluid loss. Further analysis showed that a suggestion of drinking 0.7 Liter per hour would safely hydrate over 50% of responders after one work-rest cycle. Applying this fluid volume over three work-rest cycles only put 11% of responders at risk of hypohydration vs. the 57% at risk with no fluid intake.     

Formation of trans fatty acids during the frying of chicken fillet in corn oil

To assess effects of heated edible oils on intake of trans fatty acids (TFAs); the formation of TFAs in cooking conditions was investigated by a frying system model, in which chicken fillet was fried in a commercial corn oil at 170?°C, for 12 frying cycles. The main TFAs detected in chicken fillet were trans C18:2 fatty acids (FAs) and trans C18:3 FAs, which exhibited no significant differences among the frying cycles. Besides, the content of trans C18:1 FAs were very low in all samples on different frying cycles. The intake of TFAs was estimated to be 0.06?g/100?g when chicken fillet fried in this process was consumed. These results suggest that an ordinary frying process upon a commercial corn oil has little impact on the daily TFAs intake.     

Repetitive Box Lifting Performance is Impaired in a Hot Environment: Implications for Altered Work-Rest Cycles

This study investigated the effects of environmental temperature on repetitive box lifting (RBL) performance, associated stress hormone and creatine kinase (CK) responses. Ten healthy males performed two experimental trials in a random crossover design. The trials consisted of three 40 min (10 min sitting, 20 min standing, and 10 min RBL) circuits performed in either 23°C or 38°C followed by a 180 min seated recovery period in 23°C. RBL performance (i.e., number of boxes lifted) was reduced (p ≤ 0.05) in 38°C compared to the 23°C trial. Physiological Strain Index was significantly different between trials (38°C: 8.5 ± 1.1 versus 23°C: 7.2 ± 0.7; p ≤ 0.01). Plasma testosterone was elevated (p ≤ 0.05) across both trials and then decreased at 60 min recovery, compared to pre-exercise (PRE) measures, but was higher (p ≤ 0.05) during the 38°C trial. Plasma cortisol increased (p ≤ 0.05) at 60 min during both trials and remained elevated until 120 min in 23°C, and until 60 min recovery in 38°C. Serum CK was greater through 48 hr post compared to PRE values in both trials. Thus, 10 min RBL performance was reduced in 38°C despite the 30-min rest periods between RBL intervals. Plasma testosterone and cortisol were generally higher during the 38°C trial, suggesting a greater stress response. Additional research is needed to determine optimal work:rest cycles for maximizing work performance in thermally oppressive environments.     

Stability During Frying of Moringa oleifera Seed Oil Variety “Periyakulam 1”

The frying performance of the Moringa oleifera seed oil variety Periyakulam 1 (PKM 1) from India, extracted using cold press (CP) and n -hexane (H), during frying of potatoes and cod was studied especially as regards repeated frying operations. The oils were used for intermittent frying of potato slices and cod filets at a temperature of 175±5°C for 5 consecutive days. The chemical changes occurring in the oils were evaluated. Free fatty acid content, peroxide value, specific extinction at 232 nm, polar compounds colour and viscosity of the oils all increased, whereas the iodine values, smoke points, polyunsaturated fatty acid content, induction period and tocopherol concentration decreased. The effect of the oils on the organoleptic quality of these fried foods was also determined by expert panellists. The analytical and sensory data showed that the lowest deterioration occurred in cold pressure produced oil and the highest in n -hexane extracted oil. Therefore, cold pressure oil appears to be the most appropriate for frying. Potatoes and cod were also fried in virgin olive oil in order to have a direct comparison between the different oils. The results clearly indicated that virgin olive oil has the highest resistance to thermal deterioration during frying compared with the other two oils.     

Dough Characteristics,Baking Performance,and Staling of Taftoon Bread as Affected by Supplementation with Sesame Oil

Taftoon bread is one the main traditional flat breads consumed in Iran and various parts of the Middle East. We studied the effect of different levels (1–3% w/w flour-based) of sesame oil on dough characteristics, baking performance, and staling of Taftoon bread during storage (5 days) in room (25 ± 1°C) or refrigerator (4 ± 1°C). Supplementation of dough with 1 or 2% oil led to improved Farinograph characteristics. Breads with 2% oil showed higher oven spring and specific volume and lower baking loss. The moisture and water-soluble starch content of the oil-added samples were higher, but their firmness was less than the control bread. Supplementation of bread with oil led to a lighter Hunterlab color and improved sensory scores. Generally, the best quality was obtained at the optimum usage level of 2% sesame oil. Bread staling, as monitored by moisture, water-soluble starch, and firmness analysis, was slower in refrigerator than in room.     

Removal of Phenolic Compounds from Aqueous Phase by Adsorption onto Polymer Supported Iron Nanoparticles

The removal of phenolic compounds, i.e., o-cresol, m-cresol, and p-cresol from aqueous solution have been evaluated employing activated carbon (AC) coated with polymer supported iron nanoparticles (FeNPs). The synthesized FeNPs were characterized by scanning electron microscope and X-ray diffraction analysis. High correlation coefficient values indicated that the adsorption of phenolic compounds onto AC coated with polyvinylpyrrolidon (PVP) supported FeNPs obey Freundlich and Langmuir adsorption isotherms. Higher Freundlich and Langmuir constant values for AC coated with PVP supported FeNPs indicated its greater efficiency than AC. The adsorption data are well represented by both the Freundlich and Langmuir isotherms, indicating favourable adsorption of cresols by the adsorbents. Cresols were effectively removed (90 %) by adsorption process from aqueous solution using AC coated with FeNPs. The percentage removal of above phenolic compounds was studied under varying experimental conditions such as pH, temperature, adsorbent dosage, and contact time. The adsorption of phenolic compounds is quite sensitive to pH of the suspension and optimum uptake value was found at pH 7.0. Temperature also has a favorable effect on adsorption when varied from 20 to 50°C. On the contrary, beyond 30°C, a decrease in the adsorption was noticed.     

Effect of Storage Method and Associated Holding Time on Nitrogen and Phosphorus Concentrations in Surface Water Samples

Assessments were conducted to determine the effect of sample storage method and associated holding time on surface water nutrient concentrations from field sites. Six surface water sites and two nutrient spiked, laboratory water samples were evaluated for nitrate, nitrite, ammonium, filtered orthophosphorus, and total orthophosphorus concentrations on four separate days throughout the period of 1 year. Samples stored at ambient temperature (23°C) for 24 h prior to nutrient analyses resulted in 18 % ± 2 % of results being significantly different from controls (which were analyzed immediately upon collection). Samples placed in the cooler (4°C) for 7 days prior to nutrient analyses resulted in 30 % ± 1 % of values being significantly different from controls. Samples placed in the freezer (?20°C) for 7 days prior to analyses resulted in 34 % ± 12 %, 44 % ± 10 %, and 28 % ± 5.7 % of ammonium, filtered orthophosphate, and total orthophosphate, respectively, values being significantly different from controls. This study highlights the challenges facing researchers in efficient collection, storage and nutrient analysis of samples, especially when sites are remote and difficult to access .     

Effects of Gum Arabic Edible Coatings and Sun-Drying on the Storage Life and Quality of Raw and Blanched Tomato Slices

This study was conducted to investigate the effect of gum Arabic coatings of different concentrations (1, 5, and 10%) on quality attributes (dry matter [DM], water activity [a_w], total soluble solids [TSS], pH, and browning index [BI]) of sun-dried raw and blanched tomato slices during storage (6 months). Coating at higher concentration (5 and 10%) coupled with blanching reduced the a_w and rate of increase in DM content during storage. There was no significant difference in the TSS and pH of coated and uncoated slices. Also, coating of tomato slices reduced the BI during storage and this decreases with increase in the concentration of gum Arabic. Also, the blanching has a synergistic effect in reducing the BI compared to raw slices. High concentration of gum Arabic coating prior to drying is effective in increasing the shelf-life of tomato slices.     

不同食用油和烹调方式的油烟成分分析

目的:分析不同食用油和不同烹调方式的油烟成分及其对健康危害。方法:应用粉尘采样器(15 L/min×20 min)和大气采样器(0.1 L/min×30 min)采集不同的食用油(菜籽油、花生油、大豆油、玉米油)及不同烹调方式(炸上排、炸蔬菜、炸鱼、煎鱼、炒菜)的油烟样品并分析。结果:菜籽油、大豆油及煎鱼、炒菜的油烟浓度均较高;烷烃类的含量以大豆油、炸蔬菜较高,炒菜较低;抗氧化剂存在不同油与食物中。结论:在本实验条件下,单纯食用油烹调比加入食物烹调的油烟浓度大;大豆油的油烟浓度及有机物含量均较高,炒菜的油烟浓度较大但有机物的含量最小。     

Mutagenic activity of heated potato/oil systems

Mutagens detected with Salmonella typhimurium strain TA 98 in the presence of liver S9 mix were extracted from potato slices, but not pure potato starch, after frying in oil. No mutagenic activity was detected using strain TA 100, in the presence or absence of S9 mix with either fried potato slices or potato starch. Mutagenic activity was detected at frying temperatures of 140°C and above. The mutagenic activity was limited to the outer portion of the fried potato slices and increased with frying time and temperature. Mutagenic activity ratios for extraction with both (NH4)2SO4/ NH4 OH and Na2 SO4 /NaOH were similar.     

Evaluation of soybean oil quality during conventional frying by FTIR and some chemical indexes

Conventional deep fat frying is a common food preparation technique in Mauritius. The deterioration of soybean oil, commonly used in conventional frying, has been studied during frying of potato chips. The oil was subjected to continuous frying at 180 degrees C for a total of 600 min. The quality changes in soybean oil were evaluated at 90 min interval by Fourier transform infrared (FTIR) spectroscopy and some routine chemical parameters, namely peroxide value, iodine value and free fatty acid. An increase in hydroperoxide and free fatty acid concentration has been observed during the frying process by FTIR technique and the chemical parameters, peroxide value and free fatty acid respectively. A significant decrease in triglyceride ester linkage was observed by FTIR. The linear decrease noted for iodine value (P < 0.01) indicated a general loss of unsaturation. Furthermore, FTIR studies showed a loss of cis double bonds along with an increase in trans unsaturation. The formation of unsaturated aldehyde has also been observed during the frying process by FTIR technique.     

Effects of soaking conditions on the antioxidant potentials of oolong tea

The antioxidant properties of water extracts of oolong tea (Commercial name: Fenghuangdancong) prepared using different soaking temperatures and times were investigated. The yield of powdered extract ranged from 6.7% at 80 °C for 3 min soaking to 22.7% at 100 °C for 10-min soaking. Oolong tea extracts reduced peroxidation of peanut oil and delayed the time of POV20 (peroxide value). Among these soaking treatments, soaking for 10 min in 100 °C water produced extracts with the greatest ability to inhibit the peroxidation of peanut oil. As well, the SC50 (scavenging-percentage) of the α, α-diphenyl-β-picrylhydrazyl radical (DPPH radical) was 0.119 mL of oolong tea extract using 3-min soaking at 100 °C, which is closed to the SC50 of 0.109 mL (2 mg/mL) for vitamin C. The DPPH radical scavenging activity of oolong tea extracts increased with increasing temperature of the soaking water indicating greater extraction of antioxidant compounds. In addition, inhibition of oxidation of peanut oil and DPPH radical scavenging activity by water extract of oolong tea was associated with polyphenol concentrations. Sensory assessment, found that the water extract of oolong tea using 3-min soaking at 95 °C had the strongest aroma and sweetness attributes.     

Influence of Processing Parameters on Microbial Load,Sensory Acceptability,and Mineral Contents of Dehydrated Catfish (Clarias gariepinus)

Catfish was dehydrated to improve handling using Response Surface Methodology for experimental design. Brine concentration (%), brining time (min) and drying temperature (°C) as processing parameters interacted in different combinations. Influence of processing parameters on microbial load, sensory acceptability and mineral contents of dehydrated catfish was investigated. Data analysed using regression, ANOVA and average ranking grade. Low total viable and fungi counts (ranged 1.0x10³-3.0x10³ CFU/g) with no detection of pathogen indicates safety for consumption. Brine concentration significantly (p < 0.05) influenced the texture of catfish. The model accounted for only 29.36% of the total variation (R² = 0.2936). The 6% brine, 90 min and 110°C treatment, significantly improved the overall-acceptability. Calcium content (ranged 19.60–52.60 mg/100 g) was significantly higher which could improve the nutrient intake to facilitate development and maintenance of strong bones. Knowledge about safety, acceptability and nutrient content of dehydrated catfish could contribute positively to reshaping decision-making about catfish consumption.     

The efficiency of ozonated water from a water treatment plant to inactivate Cryptosporidium oocysts during two seasonal temperatures

We investigated the efficiency of residual ozone from an advanced water treatment plant with an applied dose of 2.5 mg l^-1 to inactivate viable Cryptosporidium oocysts during summer (i.e. 24°C) and winter (i.e. 18.9°C) in Queensland, Australia. Containers for sample collection were inoculated with 1,000 oocysts l^-1 and filled with ozonated water. Ozone residual concentrations were measured at 0, 5 and 10 min intervals. Viability was determined by excystation. Non-ozonated water from the plant, trip and laboratory controls were also analysed. The applied ozone dose of 2.5 mg l^-1 produced an immediate residual concentration of 1.25 mg 1^-1 at 24°C and 1.34 mg 1^-1 at 18.9°C in unseeded samples. The initial ozone residual in seeded containers was 1.22±0.03 mg 1^-1 at 24°C and 1.37±0.04 mg 1^-1 at 18.9°C. There was a gradual increase in inactivation of oocysts, with 49% of oocysts inactivated at 0 min to 92% after 10 min at 24°C and 57% at 0 min to 92.8% at 10 min at 18.9°C.     

Amaranth Pasta in Mexico: A Celiac Overview

Amaranth is one of the most representative crops in Mexico and could represent an alternative for consumers with celiac disease. Since it possesses no gluten, it can be included in the production of non-conventional starchy foods. This work was focused on the evaluation of process conditions and adequacy of a gluten-free lasagna. Four amaranth formulations containing corn and tapioca starches at different concentrations were analyzed. Ready-to-cook samples were obtained after drying (80°C for 45 min). Pasta containing 8% corn starch reported the highest stability during blending (1.5 min) and a firmness value of 16.060 kg. This formulation was subjected to sensory analysis by 10 celiac consumers. Overall acceptability received an average score of 4.7 on a 9-point hedonic scale with a possible intention of buying.