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Buffalo meat is considered in Italy as an alternative product for its good nutritional characteristics. The influence of three cooking methods (boiling, grilling and frying) on the chemical and lipid composition of buffalo meat was evaluated. All the treatments reduced the moisture and increased protein, ash and fat content. The increase in fat content was higher after frying due to the incorporation of fat from olive oil. Fried meat had lower saturated fatty acid content due to the incorporation of mono-unsaturated (C18:1) fatty acids from oil. The incorporation of oil fatty acids caused a decrease in conjugated linoleic acid relative content. Moreover, fried meat showed the highest levels of the unhealthy trans fatty acids. Therefore, frying was shown as the worst cooking methods regarding human health. Boiling and grilling increased thiobarbituric acid reactive substances, while frying had no effect on them. [ABSTRACT FROM AUTHOR]

Abstract: A standardized textural test was developed for characterizing the banana pulp softening process during boiling. While a correlation was established between initial dry matter content and firmness, we observed large differences in cooking behavior between varieties and genotypes, with various softening rates and equilibrium retainable firmnesses. After 33-min cooking, some genotypes exhibited firmnesses 7 times higher than the softest. The biggest firmness losses relative to initial textures found after cooking were: FHIA 20 (20-fold) and FHIA 18 genotypes (40-fold) after 2h, and Guineo (100-fold) after 98min. The extent of starch gelatinization was investigated by differential scanning calorimetry and correlated to the amylographic maximum slope using rapid visco analyzer. Regardless of water uptake, the first 15-min cooking demonstrated a strong contribution by the gelatinization process to thermal softening. The firmness losses of 15 Colombian cultivated dessert and cooking banana varieties were evaluated using fractional conversion, and were best fitted by a first-order reaction (R 2 ⩾0.98). Multiple regression was shown to be suitable for preliminary cooking time prediction using Musaceae flour amylographic properties. At 30-min cooking, firmness evaluation was shown to be sufficient for identifying genotypic behavior, and therefore for predicting consumer preferences. [Copyright &y& Elsevier]

Abstract: A fuzzy logic-based design of control for a unique thermal process in the food industry is presented. Products of the thermal process are pasteurized soft-boiled eggs. The function of temperature vs. time is unique in its shape and in its required precision, since the constraints of pasteurization and cooking of soft-boiled eggs are technically contradictory. Both processes can coexist only in a quite narrow temperature range, which is a nonlinear function of egg processing time. Precision in temperature control is essential. The thermal process is implemented in an apparatus that presents a novelty on the market of industrial kitchen appliances. A precondition for the present work was simulation of thermal energy propagation in hens'' eggs of different sizes and ages. A function of temperature vs. time for the media in which eggs are immersed was defined. The function is piecewise linear in time, with horizontal and near vertical sections and abrupt transitions between them. The process is patented and the quality of pasteurization is certified by the corresponding institutes. The result is pasteurized soft-boiled eggs for consumption in hospitals, schools and hotels. The presented fuzzy control implementation of the thermal process meets the requirements, and thus the implication is that the design and implementation of temperature control based on fuzzy logic is suitable for processes where precision is required. [Copyright &y& Elsevier]

Abstract: Three Lamiaceae often used in Portuguese folk medicine: Ground ivy (Glechoma hederaceae L.), oregano (Origanum vulgare subsp. virens (Hoffmanns. & Link) Ietswaart) and mastic thyme (Thymus mastichina L.), revealed to be good sources of powerful antioxidants such as vitamins (ascorbic acid and tocopherols) and phenolics. The HPLC methodology developed for tocopherols analysis proved to be, after validation assays, sensitive and accurate. Ground ivy showed the highest levels of vitamins: ascorbic acid (168±2μg/g dry weight) and tocopherols (3692±57μg/g dry weight). The phenolics extraction was optimized using mastic tyme, and different conditions (water and ethanol:water 50%v/v, 30min at 25°C and boiling temperature; ethanol and methanol, 24h at 25°C). The best methodology (25°C, 50ml of methanol, 24h) was further applied to the other Lamiaceae. Oregano proved to have the highest radical scavenging and lipid peroxidation inhibition capacity. Particularly, the very low EC50 value (0.01mg/ml) obtained for TBARS inhibition in brain homogenates is very promising, considering that brain is highly sensitive to oxidative damage. Significantly negative linear correlations were observed between phenolics, including flavonoids, and antioxidant activity EC50 values of the three Lamiaceae. [Copyright &y& Elsevier]

Abstract: The antioxidant activity and the relationship between total antioxidant activity and the main classes of antioxidants in the seeds of bitter and sweet Chenopodium quinoa seeds were measured before and after boiling, in order to establish which one showed the best antioxidant property and how a traditional cooking method could affect it. Our results, obtained by using DPPH (1,1-diphenyl-2-picrilhydrazyl) and FRAP (Ferric Reducing/Antioxidant Power) methods, showed that antioxidant activity of bitter seeds was higher than that of sweet seeds. This activity principally depended on phenols and flavonoids in bitter seeds, while it was mainly due to phenol, flavonoid and carotenoid compounds in sweet seeds. Moreover, boiling caused a significant loss of antioxidant capacity in water. [Copyright &y& Elsevier]

In this study, bighead carp treated with two doses, i.e. 400 and 580 μg MC-LReq (Microcystin-LR equivalent)/kg bw. After dosing bighead carp with 400 and 580 ug MC-LReq/Kg bw, the mean concentrations of microcystins (MCs) was significantly higher in boiled muscle than unboiled controls. These results indicate that the potential threat of microcystins contaminated fish to humans has been underestimated. The increase in microcystins occurs by the release of phosphatase-bound microcystins by boiling. [ABSTRACT FROM AUTHOR]

Abstract: The present study focused on the development of a sensory evaluation system, using a quantitative descriptive analysis (QDA) scheme, to define the sensory attributes of boiled potato slices. A HS-SPME–GC–MS technique for a rapid determination of volatile components in boiled potatoes was also investigated. In addition to the mechanism of generation of off-odours and off-flavours in boiled potatoes (POF), the effects of the use of food additives after cooking were examined. POF formation, analysed by both sensory evaluation and HS-SPME, demonstrated an oscillating mechanism of formation of volatile compounds, probably related to enzymatic lipid oxidation and hydroperoxide generation. In particular, POF were strongly correlated with the presence of 2-pentenal, 2-hexenal, 2-heptenal, 2-pentylfuran and 2-decenal. In all, about 50 compounds were detected by HS-SPME technique. Treatment with ascorbate or citrate, after cooking and before storage, did not prevent the formation of off-flavours, in contrast to sodium pyrophosphate. Potassium meta-bisulphite prevented POF formation, but caused the creation of other off-flavours detected by a trained panel. [Copyright &y& Elsevier]

The experimental data published by various authors who studied the burnout heat transfer in boiling have been analyzed. It is shown that the critical heat flux depends substantially on the physical properties of both the boiling liquid and cooled wall and its geometric parameters. [ABSTRACT FROM AUTHOR]

Abstract: Adequate dietary zinc is essential for appropriate growth, neurological development, and immune function in all age groups, especially in children. Eggs are a potentially attractive means of delivering dietary zinc. This study used an in vitro continuous-flow dialysis (CFD) method to determine the effect of cooking (boiling or frying) on bioaccessibility of zinc from eggs which had been biofortified in vivo. The intrinsically zinc-enriched eggs with the highest level of zinc (18μg/g) provided the highest available zinc at 75%. There was no statistically significant difference in the bioaccessibility of zinc from eggs enriched with inorganic zinc versus enrichment with organic zinc. The intrinsically zinc-enriched eggs from hens fed both organic and inorganic forms with the maximum available zinc (about 13.5μg zinc/g) were selected to study the effect of cooking. Boiling and frying did not have any adverse effect on zinc bioaccessibility in the eggs intrinsically enriched with inorganic zinc. However, boiling reduced by about 6% and frying reduced by about 10% the bioaccessible zinc in the control and eggs intrinsically enriched with organic zinc. One intrinsically enriched egg could provide 142% of the daily zinc requirement for a child aged one year. [Copyright &y& Elsevier]

Abstract: The effect of common domestic processing methods, such as splitting, soaking, boiling and pressure-cooking on the nutritionally significant starch fractions such as rapidly and slowly digestible starches (RDS and SDS), resistant starch (RS) and total starch (TS) in two legumes, Red kidney bean (Phaseolus vulgaris) and Yellow and Green peas (Pisum sativum) were studied. The legumes had comparatively high amount (>30%, dry basis) of RS. Soaking of all legumes resulted in reduced starch fractions, possibly due to leaching of soluble fractions. Ordinary cooking of soaked as well as unsoaked seeds led to a significant (P <0.01) decrease in RS and increase in RDS, SDS and TS. Pressure-cooking led to even greater reduction in RS and a greater increase in RDS. Cooking of legumes gelatinizes the starch and opens up the starch structure which makes them vulnerable to α-amylase hydrolysis. Splitting of legumes markedly affects the digestibility as well as RS content of raw as well as processed legumes indicating that the seed coat plays a key role in the digestibility of starches in these seeds. Overall, the enzyme resistant starch fraction of legumes was rendered more digestible by all the domestic cooking methods used. [Copyright &y& Elsevier]

Abstract: Stewing of rice grains by steam after boiling in excess water can be used for cooking rice perfectly. The effects of this procedure in cooking of three varieties of Iranian rice (Sang Tarom, Domsiyah and Fajr) on textural and morphological properties of cooked rice grains were investigated. The results showed that this step in rice cooking reduced the hardness and increased the adhesiveness of rice grains significantly. By the use of the scanning electron microscopy, it was shown that the outer surface of cooked rice stewed by steam had less porosity and closer pores due to the modification during cooking, and better gelatinization and more expansion of starch granules compared to non-stewed samples. The use of this procedure in rice cooking to provide a fully cooked and gelatinized, softer and stickier final product is recommended. [Copyright &y& Elsevier]

Abstract: Antioxidant activity of polysaccharide fractions isolated from Lycium barbarum Linnaeus was evaluated. Polysaccharides were extracted with boiling water, followed by precipitating with ethanol, protein hydrolysis, dialysis, and fractionation with a DEAE–Sepharose CL-6B column. A total of 4 fractions, including 1 neutral polysaccharide (LBPN) and 3 acidic polysaccharides were obtained, and compared with crude polysaccharide (CP), crude extract of polysaccharide (CE), deproteinated polysaccharide (DP), and deproteinated and dialyzed polysaccharide (DDP) for antioxidative activity. With the exception of CE and DDP, most polysaccharides were effective in scavenging DPPH and ABTS + free radicals, superoxide anion and hydroxyl radical at 1000μg/mL. [Copyright &y& Elsevier]

Abstract: Functional properties of raw, roasted and water-boiled canola meal (CM) were investigated and compared to those of soybean (SM) and flaxseed meals (FM) aiming to provide practical information to the manufacturers on the possible incorporation of this meal into new food products. CM, SM and FM showed significantly different functional properties. Heat treatments significantly increased water and oil absorption capacities while reduced nitrogen solubility of different meals. Neither roasting nor water boiling significantly affected the gelation of the meals. CM showed the best emulsification and foaming properties followed by SM and FM. Both emulsifying and foaming properties were significantly reduced after heat treatments. Raw, roasted and water-boiled CM revealed unique functional properties, which could be a base for selection in different applications. This study shows the potential of CM for incorporation into new functional foods and value-added products. [Copyright &y& Elsevier]

Abstract: The effect of water soaking, boiling, roasting, microwave cooking, autoclaving, fermentation and micronization on the nutritional quality of cowpea, pea and kidney bean was investigated. Pea seeds showed the highest crude fat, crude fiber and the lowest moisture contents while kidney bean had the lowest crude fat and the highest crude protein and ash contents. Glu and Asp were the main amino acids in all legumes while Cys and Met contents were the lowest. The protein efficiency ratio (PER), protein chemical score (CS) and the essential amino acid index (EAAI) of raw seeds ranged from 2.15 to 2.95, 39.07 to 68.30, and 55.49 to 62.84, respectively. Soaking, boiling, microwave cooking and autoclaving increased the total essential amino acids in all samples. Furthermore, raw and treated samples showed higher Lys content than the reference protein. Autoclaving was the most effective in improving protein quality followed by micronization, microwave cooking and fermentation. In addition, in vitro protein digestibility was improved after soaking, boiling, microwave cooking, autoclaving and fermentation but was reduced after roasting and micronization. [Copyright &y& Elsevier]

Abstract: Raw and treated cowpea, pea and kidney bean seeds were investigated for their content of antinutritional factors including tannins, phytic acid, trypsin inhibitors and oligosaccharides. Treatments applied included water soaking, boiling, roasting, microwave cooking, autoclaving, fermentation and micronization. Kidney bean contained the highest antinutrient content among all investigated seeds. The least tannins and phytic acid contents were recorded in Canadian cowpea while Canadian pea showed the lowest TIA. All treatments conducted caused significant decreases in tannins, phytic acid, TIA and oligosaccharides as compared to the raw seeds. Boiling caused the highest reduction in tannins followed by autoclaving and microwave cooking. Autoclaving and fermentation were the most effective in reducing phytic acid content. Heat treatments (boiling, roasting, microwave cooking and autoclaving) brought a total removal of trypsin inhibitors of all samples. Furthermore, autoclaving caused the highest reduction in oligosaccharides followed by fermentation while the least reductions were caused by either roasting or micronization with no significant difference between these two treatments. [Copyright &y& Elsevier]

Abstract: To clarify the effects of freshness of raw fishes and boil-retort process on the antioxidant activities, we determined stable 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging capacity and ferrous reducing power in the ethanol extract solution of chub mackerel Scomber japonicus and Pacific saury Cololabis saira meat before and after retort process (115°C for 80min). The antioxidant activities in boiled (mizu-ni) and canned fish were also investigated. The mizu-ni can products contain only fish meat and little salt. The radical-scavenging capacity was increased about ten times in chub mackerel and about six times in Pacific saury by the retort treatment. Both antioxidant activities of raw chub mackerel meat increased during 10 days storage at 4°C. On the other hand, the increasing of antioxidant activity in the stored and retorted meat was observed until four days storage. In the case of mizu-ni canned products, the antioxidant activities were high in common-grade cans rather than high-grade cans. Almost the antioxidant activities shown in this study were correlated with absorbance at 245nm. We consider that the results about differences of antioxidant activities between raw and retorted fishes or fresh and several day stored fishes are useful for the food functions and safeties. [Copyright &y& Elsevier]

Thermal decomposition of dried crystalline powder obtained from titanium(IV) bis(acetylacetonate) diisopropoxide (75% solution in 2-propanol) ( 1) was monitored by simultaneous TG/DTA, EGA-FTIR and EGA-MS measurements and the results were compared with those of amorphous powder obtained by gelling of acetylacetonate-modified titanium(IV) tetra-isopropoxide at molar ratio of 1:2 in boiling 2-methoxyethanol ( 2). Thermal degradation of 1 in the temperature range of 25–700°C consists of 5 steps with a total mass loss of 62.5%. EGA by FTIR and MS revealed the release of H2O below 120°C; followed by an intensive evolution of acetylacetone around 245°C. The release of acetone and acetic acid occurs up to 270°C and that of CO and CO2 up to 530°C. [ABSTRACT FROM AUTHOR]

In many rural areas of Mexico, pork infected with Taenia solium is still being consumed, mainly because of the domiciliary slaughter of animals in villages where meat inspection does not exist. It follows that taeniasis cysticercosis continues to be an important health problem both for humans who suffer from taeniasis and neurocysticercosis and for pork producers due to the economic losses involved. In order to recommend a simple and effective method for housekeepers in rural zones to inactivate the metacestodes, infected pork cut in slices of 4 cm thickness was exposed to different temperatures and periods of time. Evagination trials were done and hamsters were infected with the treated larvae. The results show that metacestodes in pieces of pork of 4 cm thickness are innocuous after boiling them for 15 minutes or freezing them at 0° C for 96 hours or for 48 hours at -20° C, but the latter is not feasible in a rural environment. Boiling or freezing at 0° C in a domestic refrigerator is recommended as a simple procedure in marginated areas to avoid the growth of Taenia solium in human beings and thus interrupt the cycle of the parasite. [ABSTRACT FROM AUTHOR]

Abstract: Taro corms were cooked in four different mediums (water, tamarind solution, lemon solution, or steam) during 25min. Changes in hardness, soluble sugars, soluble proteins, degree of gelatinisation (iodine index), degree of cell separation (VICS), resistant starch, total oxalate, absorbance at 280nm (A 280) and 450nm (A 450) were evaluated. The results showed that irrespective of the cooking medium, the hardness, soluble proteins, and resistant starch significantly decreased during cooking while A 280, A 420, iodine index, VICS and soluble sugars significantly increased. A significant correlation was observed between the hardness and the iodine value, resistant starch, soluble sugars and VICS, suggesting multiple mechanisms involved in the softening of taro corms during cooking. It was observed that steam cooking of the slices induces the highest softening while boiling in water induces the lowest softening of the corms. However cooking in tamarind and lemon solutions induced a bitter and acid taste to the corms. While no consistent change was observed during steaming, significant reduction was observed in the oxalate content during boiling probably due to leaching in boiling solutions and acid hydrolysis. [Copyright &y& Elsevier]

Abstract: Migration characteristics of nanoparticles in the pool boiling process of nanorefrigerant and nanorefrigerant–oil mixture are fundamental knowledge for the application of nanorefrigerants in refrigeration systems. In this paper, migration characteristics of nanoparticles in the nanorefrigerant–oil mixture as well as in the nanorefrigerant were experimentally studied and numerically simulated. Experimental results show that the migrated mass of nanoparticles in the pool boiling process of both nanorefrigerant and nanorefrigerant–oil mixture, increase with the increase of the original mass of nanoparticles and the mass of refrigerant; the migration ratio decreases with the increase of volume fraction of nanoparticles; the migrated mass of nanoparticles and migration ratio in the nanorefrigerant are larger than those in the nanorefrigerant–oil mixture. A numerical model, which can qualitatively well predict the migrated mass of nanoparticles, was established, and the deviations between the model predictions and experimental data were in the range of 7.7–38.4%. [Copyright &y& Elsevier]

In this study, effects of boiling and hot smoking on proximate composition and shelf life of mussels stored at 4 ± 1C were investigated. Dry matter, crude protein, crude fat and crude ash levels were determined as 13.94, 10.30, 1.14 and 0.95% in fresh mussels 20.75, 13.83, 2.11, 0.77% after boiling and 39.57, 22.22, 10.04%, 6.02% after hot smoking, respectively. Trimethylamine nitrogen values in fresh, boiled and hot smoked mussels were determined as 1.13, 1.01 and 1.07 mg/100 g, respectively, and increased to 24.35 mg/100 g at 18th day of the storage period. pH value in hot smoked mussels ranged between 4.85 and 4.51 during the chilled storage. According to the results, mussels smoked by hot smoking and stored at refrigerator temperature (4 ± 1C) for 12 days can be consumed. PRACTICAL APPLICATIONS In many countries, smoking is used to obtain products that are popular for their texture and flavor. Mussels, scallops and oysters are some of the important mollusk species that are smoked and eaten in different parts of the world. In this research, the effects of hot smoking process (for 30 min at 82C) on proximate composition and shelf life of Mediterranean mussel stored at 4C was investigated. [ABSTRACT FROM AUTHOR]

Rheological parameters of Juniperus drupacea fruit pekmez were evaluated using a rotational viscometer at 10, 20, 30, 40, and 50 °C and at concentrations of 62.8, 68.9, 72.0, and 75.2% total soluble solids. The flow characteristics of Juniperus drupacea fruit pekmez were described by the power law and Herschel-Bulkley models. The Herschel-Bulkley model was found to be the best to describe the rheological property with the coefficient of determination higher than 0.993. Juniperus drupacea pekmez exhibited a time-independent shear thickening behavior. The effect of temperature on viscosity can be described by means of an Arrhenius equation. Depending on the soluble solid contents, the activation energies for flow of diluted samples vary from 78.23 to 60.38 kJ/mol. The effect of soluble solids on viscosity can be described by an exponential equation. Experimental data were fitted to several models in order to describe the effect of temperature and soluble solid co [ABSTRACT FROM AUTHOR]

Experiments show that in low-and high-velocity flows the boiling process is fundamentally different: in the former, the fluid boils on the walls, and in the latter in the volume. In high-velocity flows, the boiling intensity is orders of magnitude greater. In modeling fast and slow flows, the number of bubbles, which is a free parameter of the model and must be specified, differs by orders of magnitude. When high-speed flows of different kinds are modeled (vessel depressurization, nozzle flows) the number of bubbles specified also differs by orders of magnitude. In this study, we formulate the hypothesis that in both kinds of flows the process of boiling starts similarly, namely, on the walls. However, in high-speed flows the number of bubbles increases by orders of magnitude due to bubble fragmentation. As a result of intense fragmentation, the system “forgets” the initial number of bubbles and the process becomes volume boiling. This approach makes it possible to construct a universal model of boiling. To test this hypothesis, we constructed a mathematical model which takes into account the possibility of bubble fragmentation due to the instability developing under the action of centrifugal accelerations of the bubble surface. This model was used to calculate the process of depressurization of a high-pressure vessel. The calculations demonstrated that, for any initial number of bubbles, 1 ms after depressurization the bubble number attains the same level. Bubble fragmentation takes place in “self-sustained detonation waves”. The stationary structure of detonation waves in a boiling fluid is investigated. A scheme of the wave structure according to which the wave consists of a shock wave and a relaxation zone is proposed. Calculations of a boiling-fluid flow through a Laval nozzle reveal the periodic appearance of detonation waves. Accordingly, nozzle flows should be accompanied by significant oscillations of the parameters. [ABSTRACT FROM AUTHOR]

The effects of different cooking methods (boiling, frying and microwave cooking) on the antioxidant activity of some selected vegetables (peas, carrot, spinach, cabbage, cauliflower, yellow turnip and white turnip) were assessed by measuring the total phenolic contents (TPC), reducing power and percentage inhibition in linoleic acid system. TPC (gallic acid equivalents g/100 g of dry weight) and reducing power of the methanolic extracts of raw-, microwaved-, boiled- and fried vegetables ranged 0.333–2.97, 0.52–2.68, 0.48–2.08, 1.00–2.02 and 0.391–2.24, 0.822–1.10, 0.547–1.16, 0.910–4.07, respectively. The level of inhibition of peroxidation ranged 71.4–89.0, 66.4–87.3, 73.2–89.2 and 77.4–91.3%, respectively. Antioxidant activity of the vegetables examined was appreciably affected because of varying cooking treatments. TPC of vegetables, generally, decreased by boiling, frying and microwave cooking. There was a significant ( P < 0.05) increase in reducing power as a result of frying. However, boiling and microwave cooking did not affect reducing power. Inhibition of peroxidation increased by boiling and frying, whereas, in contrast it was decreased by microwave cooking. The results of the present investigation showed that all the cooking methods affected the antioxidant properties of the vegetables; however, microwave treatment exhibited more deleterious effects when compared with those of other treatments. Thus an appropriate method might be sought for the processing of such vegetables to retain their antioxidant components at maximum level. [ABSTRACT FROM AUTHOR]

Abstract   For many industrial, medical and space technologies, cryogenic fluids play indispensable roles. An integral part of the cryogenic transport processes is the chilldown of the system components during initial applications. In this paper, we report experimental results for a chilldown process that is involved with the unsteady two-phase vapor-liquid flow and boiling heat transfer of the cryogen coupled with the transient heat conduction inside pipe walls. We have provided fundamental understanding on the physics of the two-phase flow and boiling heat transfer during cryogenic quenching through experimental observation, measurement and analysis. Based on the temperature measurement of the tube wall, the terrestrial cryogenic chilldown process is divided into three stages of film boiling, nucleate boiling and single-phase convection that bears a close similarity to the conventional pool boiling process. In earth gravity, cooling rate is non-uniform circumferentially due to a stratified flow pattern that gives rise to more cooling on the bottom wall by liquid filaments. In microgravity, there is no stratified flow and the absence of the gravitational force sends liquid filaments to the central core and replaces them by low thermal conductivity vapor that significantly reduces the heat transfer from the wall. Thus, the chilldown process is axisymmetric, but longer in microgravity. [ABSTRACT FROM AUTHOR]

Onion, in its raw form, is recognized as an antiplatelet agent that may contribute to the prevention of cardiovascular disease. In raw onions, the content of pyruvate, is significantly correlated with antiplatelet activity (AA) and the sensory perception of pungency. However, onion is generally cooked before consumption. Herein, we examine the effect of heating — using different boiling intensities — on the in vitro antiaggregatory activity (IVAA), the pyruvate concentration and the flavor (pungency) of crushed-onion samples. In general, heating is detrimental for onion AA. Boiling for 3 min has no significant effect on platelet aggregation, as compared to raw onion. Heating for 46 min completely suppresses IVAA, whereas samples boiled for > 20 min have pro-aggregatory effects. Significant differences in AA are found between the blood donors. Pyruvate content is not reduced after 30 min boiling. Pungency ratings decrease with the intensity of the heat treatment. Strong significant positive correlations are found between IVAA and pungency, but not between pyruvate and the former two variables. Our results suggest that: (i) in order to obtain the maximum health benefits onions should be eaten raw or moderately cooked, (ii) extensive heating may result in pro-aggregatory effects, (iii) pyruvate is not a good indicator of AA in cooked onions, (iv) the decrease in IVAA and pungency during onion cooking may be due to degradation of sulfur compounds (e.g. thiosulfinates) which are, likely, less tolerant than pyruvate to the high temperatures. [ABSTRACT FROM AUTHOR]

Abstract: Asian styles of noodle products represent the end-use of at least one eighth of all wheat produced globally and are potentially a good dietary source of essential nutrients. In order to investigate the factors influencing thiamin content, three styles of noodles were made under controlled laboratory conditions. The losses during preparation of dried white salted noodles were low. Boiling of these noodles resulted in a 43% decline in total thiamin level. In contrast, the relative losses of thiamin were high for yellow alkaline noodles and these occurred at each step in the process including dough mixing and drying. For instant noodles decreases also occurred at each step and these were smaller than for yellow alkaline but greater than for white salted noodles. The variation in ingredients and processing accounts at least partially for differences in thiamin levels of different noodle styles. [Copyright &y& Elsevier]

The article presents several examples of Fermi problems adapted from the 37th International Physics Olympiad (IPO) held in Singapore from July 8-17, 2006. The two effects that were used to determine the camera's effectiveness as a photographic tool are diffraction by the aperture and the pixel size. It cites the amount of cooking time needed to make a hard-boiled egg. The solution to know the frames in an animation movie is presented.

Soaking and boiling whole wheat kernels in water are the key steps in the preparation of an Egyptian dish called 'balila'. The effects of washing, soaking and boiling wheat kernels in tap water or in 0.1 M Na2CO3 solution on the deoxynivalenol (DON) content of the wheat kernels were studied. Boiling contaminated wheat kernels in water reduced the DON content of the grain by 70%. The mechanism of decontamination due to boiling is probably a leaching of DON out of the grain into the boiling medium. A combined treatment of soaking in 0.1 M Na2CO3 solution (pH 11) with subsequent boiling reduced the DON content of the grain by 93%. Data suggest that apart from leaching DON out of the kernels into the boiling medium, a degradation of DON occurred in alkaline medium. Modifying the traditional process of 'balila' preparation by using Na2CO3 solution may be useful to reduce the risk of mycotoxin exposure via 'balila'. [ABSTRACT FROM AUTHOR]

The effects of dry- (roasting) and moist-heat (boiling) treatments on the biochemical characteristics of Terminalia catappa (tropical almond) seed were determined. There were no significant differences in crude protein, fat, ash, and carbohydrate content of the seeds with respect to processing. Boiling increased significantly (P <0.05) the crude fibre, however roasting reduced it. Roasting had a better effect on the total dietary fibre (TDF) and gross energy level of the seeds than boiling. There were no significant differences in the effects of both processes on the amino acid, fatty acid and sugar profiles of the seeds. Roasting improved the potassium, phosphorus, copper and iodine, reducing the magnesium, calcium, zinc and iron contents. Boiling improved the sodium and selenium and reduced the potassium, magnesium and calcium levels. [ABSTRACT FROM AUTHOR]

Purpose - The aim of this study was to evaluate the influence of temperature and action time on the extraction rate of carbohydrates of Jerusalem artichoke concentrate powder and inactivation of inulin during boiling and sterilization. Design/methodology/approach - Water suspension of Jerusalem artichoke concentrate (5g/100ml) at 25, 50 and 100?C was tested after 5, 15, 30 and 60min to determine the content of inulin, glucose, fructose and sucrose and evaluate the extraction rate. The stability of inulin was studied after boiling and sterilization at 120?C during 1, 2 and 3h. The extraction rate was evaluated by Fourier-Transform Infrared (FT-IR) spectroscopy as well. Findings - It was shown that extraction of soluble carbohydrates - fructose, glucose, sucrose and inulin, from water suspension of Jerusalem artichoke concentrate was practically completed in 5min at 25?C. The extraction rate was not significantly influenced by temperatures lower than 100?C. Inulin was stable during boiling for 1h but sterilization for 1h caused significant losses. Infrared spectral analysis of soluble and insoluble fractions showed that inulin was practically fully extracted. Originality/value - The paper shows that inulin can be easily extracted from Jerusalem artichoke concentrate powder even at 25?C and it maintains for 60min at temperatures up to 100?C, nevertheless boiling or sterilization at higher temperatures for longer time causes significant loses of inulin and consequently the functional quality of Jerusalem artichoke powder. These results must be taken into account when applying inulin concentrates as functional food components. [ABSTRACT FROM AUTHOR]

Purpose - This study aims to investigate the levels of some anti-nutritional factors and minerals and the effect of boiling or roasting on selected commonly consumed Caribbean tuber crops. Design/methodology/approach - Three commonly consumed tuber crops in the Caribbean namely: Yellow yam (Dioscorea cayenensis), Cocoyam (Xanthosoma sp.) and Sweet potato (Ipomea batatas) were harvested from farmers' field in the Parish of Manchester, Jamaica and assessed in their boiled, raw and roasted forms for levels of some anti-nutritional factors and minerals. Findings - Zinc and iron levels were highest in raw Yellow yam, while the highest levels of calcium were observed in Sweet potato. The phytic acid to zinc molar ratio was higher than 15 in all the tuber crops in their raw and roasted forms. Boiling reduced this ratio to below 15 for Yellow yam and Cocoyam but still remained above 15 for Sweet potato. Cyanoglucoside level was highest in raw Sweet potato followed by Yellow yam and Cocoyam. Boiling or roasting reduced the levels of cyanoglucosides. Roasting greatly lowered the level of trypsin inhibitor activity compared to boiling. The highest level of trypsin inhibitor activity was recorded in the raw tubers, and slight reductions were observed upon processing. Practical implications - Trypsin inhibitor was more stable to heat treatment compared to similar tubers grown in Africa. It may be beneficial to isolate and characterize trypsin inhibitor in these Caribbean tuber crops for utilization in nutraceutics. Originality/value - This study shows that the two traditional processing methods were effective in lowering the levels of anti-nutritional factors. [ABSTRACT FROM AUTHOR]

The effects of soaking, boiling and combination of soaking and boiling at various treatment levels on the detoxification of trypsin inhibitor, cyanogenic glycoside, hemagglutinin, alkaloids and tannin in pigeon pea and vegetable cowpea were studied. Soaking was carried out for 6, 12 and 18 h while boiling was carried out for 40, 60 and 80 min. In combined soaking and boiling method, the beans were soaked for 12 h and then boiled for 40, 60 and 80 min. The results showed that the most effective method of detoxifying any of the toxicants was soaking for 12 h and boiling for 80 min. This method was able to reduce the trypsin inhibitor from 12.45 to 2.59 TUI/mg in pigeon pea and 25.60 to 3.20 TUI/mg in vegetable cowpea. The method also reduced the hemagglutinin content from 27.88 HU/mg to nil and 49.50 to 9.52 HU/mg; the cyanogenic glycoside from 40.50 mg/kg to nil and 83.81 to 5.06 mg/kg; alkaloids from 0.26 to 0.16% and 9.61 to 0.50%; and tannin from 1.60% to nil and from 3.42 to 1.28% in pigeon pea and vegetable cowpea, respectively. This method was found to be more potent in eliminating any of the toxicants rather than soaking or boiling alone. [ABSTRACT FROM AUTHOR]

The aim of this study was to determine the effect of different cooking processes (microwaving, roasting, boiling, grilling and frying) on naturally incurred enrofloxacin residues in chicken muscle. Enrofloxacin and its metabolite, ciprofloxacin, were analysed using a validated LC–MS method with limits of detection (LOD) and quantification (LOQ), respectively, of 2 and 5&ThickSpace;ng&ThickSpace;g -1 quinolones in muscle samples. The method was shown to be linear over the range 5–500&ThickSpace;ng&ThickSpace;g -1 . Mean intra-day relative standard deviation (RSD) at a concentration of 50&ThickSpace;ng&ThickSpace;g -1 ( n &ThickSpace;=&ThickSpace;6) was 6%; inter-day RSD was 12%. A recovery study demonstrated that 65–101%, of the drug and metabolite could be recovered from the tissue. The RSD with naturally incurred roasted chicken breast was 9.18% at a concentration of 11&ThickSpace;±&ThickSpace;1.01&ThickSpace;ng&ThickSpace;g -1 ( n &ThickSpace;=&ThickSpace;6). In water, enrofloxacin remained stable for 3&ThickSpace;h when heated at 100°C. It was concluded that residue data from raw tissue are valid for estimation of consumer exposure to this drug, as well as the ADI calculations because cooking procedures did not affect enrofloxacin residues, which remained stable during heating. However, there was an apparent decrease in quinolone concentration in tissue because some was lost by exudation into the liquid used for cooking. Conversely, for a cooking procedure with water loss, there was an apparent increase in residue concentration. [ABSTRACT FROM AUTHOR]

White salty and yellow alkaline noodles were prepared raw and also as cooked for varying periods between 2 and 14 min by boiling in distilled water and then tested in tension at room temperature on a universal testing machine to characterize their stress–strain and fracture behaviors. From these tests, it was deduced that a period of∼ 7 min of cooking time for both types of noodles produced the greatest notch sensitivity. A sensory panel was constructed to evaluate the sensorily perceived optimal cooking time of these products. This perception correlated well with the notch sensitivity results obtained from the tensile tests. From a materials perspective, solids that are notch-sensitive have firm mechanical links between their structural components. Raw, undercooked and overcooked noodles variably lack this. These results suggest that notch sensitivity may be important in sensory perception and help in constructing a physical definition of “cookedness” for these types of food. [ABSTRACT FROM AUTHOR]

Abstract: The vacuum cooling of cooked meats is described in this paper. Based on the energy and mass balance, a modified mathematical model based on a previous model is developed to analyze the performance of the vacuum cooler and the evaporation-boiling phenomena during vacuum cooling of cooked meat. Validation experimentation is performed in the designed vacuum cooler. Boiling occurs inside the cooked meat. There is a boiling front, and the boiling front moves toward the center of the cooked meat as the vacuum cooling proceeds. The experimental data are compared with the simulation results. It is found that the differences of the temperature between the simulation and the experimentation are within 5°C, and the deviation of weight loss between the simulation and the experimentation is within 4%. The simulation results agree with the experimental data well. The modified model can be used to predict the variation of the vacuum pressure in the chamber, the temperature and pressure distributions and the weight loss profiles of cylindrical cooked meats. [Copyright &y& Elsevier]

Pacific Island people commonly eat taro (Colocasia esculenta var. Schott) as a staple food in their home islands and also like to consume this familiar food when living in New Zealand. Some of these foods are imported from the islands and some attempts are, currently, being made to grow these crops in New Zealand. The taro leaves in this experiment were grown in a greenhouse in the North Island of New Zealand. The soluble oxalate content of the raw leaves was 236.10 mg oxalate/100 g wet matter (WM). Soaking the raw leaves in water for 30 min marginally reduces the soluble oxalate content by leaching into the tap water. Soaking for 18 h results in a 26% reduction in the soluble oxalate content of the raw leaves. During the soaking treatments the insoluble oxalate (calcium oxalate) content of the leaves remained constant (mean 171.64 mg oxalate/100 g WM).Boiling the taro leaves resulted in a 36% loss of soluble oxalates, while the soluble oxalate content of baked tissue was very similar to the raw tissue. The mean insoluble oxalate content of the raw, boiled and baked tissue was 226.28 mg oxalate/100 g WM. Overall, boiling the taro leaves was an effective way of reducing the soluble oxalate content of the cooked tissue. [ABSTRACT FROM AUTHOR]

Experiments on cooking characteristics of full-fat and defatted soya flakes were performed using different cooking treatments, viz., normal boiling, cooking with additive salts, pressure cooking to explore the feasibility of using such flakes in the preparation of broth. The results indicated that the optimum cooking time of soya flakes can be successfully reduced from 142min by normal boiling to 69min by pre-heating and boiling in 1% sodium bicarbonate (NaHCO3) and 11min by pre-heating and pressure cooking in 1% NaHCO3 for the preparation of good-quality broth thus reducing time and energy in cooking considerably. [Copyright &y& Elsevier]

A cylindrical shaped box type solar cooker was constructed and its thermal performance was tested under the prevailing weather conditions in Karabuk, Turkey. Experiments were conducted on a single glazed cooker with a plane reflector and one cooking pot during August 2004. The international test procedure was applied to the solar cooker and the stagnation temperature, and the sensible water heating tests were performed to predict the heating characteristic curves. The results obtained from the tests were used to calculate the two figures of merit, overall thermal efficiency, specific and characteristic boiling times as well as the cooking power. The first figure of merit obtained was greater than value suggested in the international standard test procedure. The second figure of merit was found to increase almost linearly with the quantity of water. These figures of merit are then used to predict the characteristic heating curves. Good agreement exists between the predicted heating curves and the experimental results. The solar cooker with 1 m2 aperture area is able to boil 1 kg water in 13·6 min with 30·5% daily thermal efficiency. [ABSTRACT FROM AUTHOR]

The article focuses on a study which examined the volatile compounds of traditional Chinese Nanjing water-boiled salted duck (NJSWD) during its processing stages. A number of ducks were processed via dry-curing, brining, roasting and boiling in this study. The total number of volatile compounds identified in duck meat was 92. Results of the study showed that there was an increase in aldehydes, alcohols and hydrocarbons during dry-curing. It cites aldehydes as the most common compound in NJSWD.

The superheated steam drying at reduced pressure is performed, and the effects of operational conditions such as drying pressure and temperature on the drying characteristics are examined. In order to obtain the basic guideline for the design of the superheated steam dryer at reduced pressure, the heat flux to sample was calculated and the optimal conditions were estimated. After the sample temperature reached at the boiling point, the temperature was maintained at the boiling point and the drying rate became almost constant. Once the sample was dried out, the temperature suddenly increased up to the drying gas temperature. From the calculation of combined heat flux, the followings were found. The contribution of radiative heat transfer to the combined heat flux became larger as the drying pressure was lower. The combined heat flux had a maximum value against the drying pressure. The optimum drying pressure, which gave the maximum heat flux, became lower as the drying gas temperature decreased. It was found that reduction in the drying pressure is effective for the enhancement in drying performance. [ABSTRACT FROM AUTHOR]

This article presents a method allowing the effective diffusion coefficient to be determined from experimental drying kinetics as a time-dependent parameter. The method combines an analytical solution of Fick's equation in which the Fourier number is raised to the empirical power ( a ), with a semi-theoretical equation derived for quasi-stationary conditions. The method has been validated by applying the resulting equation to literature data on drying kinetics for parboiled rice and cut tobacco leaves as they approach a sphere and a slab, considered to be standard geometries in diffusion problems. [ABSTRACT FROM AUTHOR]

Drying kinetics and quality parameters of potato cubes were evaluated as affected by high pressure processing and hot water blanching. The potato cubes in 1% citric acid solution as immersion medium were pressure treated at 400 MPa for 15 min. Hot water blanching was conducted in boiling water for 3 min. Drying kinetics and quality parameters (i.e., rehydrability, texture, color and apparent density) were assessed for the high pressure–treated and water-blanched samples and for dehydrated and rehydrated samples. Drying rates were found to be higher ( p [ABSTRACT FROM AUTHOR]

Soybean protein is highly rich in the essential amino acid needed by human body. In the developing countries, its use will be more generally acceptable when converted to flour like wheat. This work focused on establishing the optimum conditions of some physical characteristics of soybean for high quality and acceptable soy flour. The characteristics studied for soybean samples subjected to heat treatment of boiling and oven drying were the effect moisture content (MC) and the hull thickness on the quality of the flours. Ten samples of Tax 1485 at different moisture levels ranging from 20.6% to 8.6% and five varieties (Tax 1440-1E, Tax 1740, Tax 1485, Tax 1456 and Tax 1448-2E) obtained from International Institute for Tropical Agriculture (IITA), having different hull thicknesses were used. Soybean with mixed varieties commonly found in the open markets was also used to compare the effects of MC on the studied parameters. Flours obtained from the samples milled in an attrition mill were subjected to proximate, sieve and organoleptic evaluations. The hull thickness was found to have no correlation with protein retention, acceptability and our yield, but moisture content has a very significant effect on the qualities. Between moisture content of 20.6% and 8.6%, protein and acceptability reduced from 40.0% to 27.7% and 4.3 to 2.2 respectively while yield increased from 0.9% to 5.8%. Though protein was reducing with reduced MC, there was no significant difference (p<0.05) in protein retention between MC of 20.6% and 10.1% but it became significant at 9.4%. There was no significant difference in acceptability from 13.6% to 8.6% MC and between 8.9% and 11.0% MC for flour yield. Both Tax 1485 and mixed varieties followed the same trend only that they have different absolute values. The mixed varieties however had no significant difference in protein content between 19.8% and 10.2% MC. These results, therefore established that to obtain acceptable soy flour of high flour yield and protein content, moisture content of soybean after processing should be about 10% (dry basis). [ABSTRACT FROM PUBLISHER]

In the developing countries animal proteins are very expensive and cannot meet with the protein requirement of the current explosive population trend hence, supplementing with plant protein is pertinent. Soybean, which is widely consumed when processed to flour and flour products, is one of the best substitutes if properly processed. This study, therefore, aimed at establishing the best thermal treatment among the commonly used methods that will conserve the protein content of soy flour maximally, result in high flour yield and acceptability. Four different methods: Roasting (ROA), Extrusion (EXT), Boil and Sun Dry (BSD) and Boil and Oven Dry (BOD), were used to prepare samples from Tax 1448 soybean variety obtained from International Institute for Tropical Agriculture (IITA) and mixed variety obtained from market. The samples were milled in an attrition mill and the flours obtained were subjected to proximate, sieve and organoleptic evaluations. The results of the experiment, showed a protein content of 40.5, 40.7, 40.1 and 40.3%, flour yields of 32.0, 3.7, 29.7 and 37.9%, and acceptability of 58.0, 61.0, 36.0, and 48.0% and protein content of 33.7, 34.4, 32.7 and 32.7%, flour yields of 17.0, 5.0, 14.1 and 12.3%, and acceptability of 64.0, 68.0, 48.0 and 60.0% for BOD, EXT, ROA and BSD respectively for Tax 1448 and mixed variety. These results indicated that BOD is a better method over others. EXT, though, has the highest acceptability and protein contents, these values (p < 0.05), have no significant difference from those of BOD. EXT however has a very low flour yield. This study has therefore established that BOD is the best of the commonly used domestic methods for producing acceptable soy flour of high protein content and flour yield. [ABSTRACT FROM AUTHOR]

The effects of boiling on the microstructure of yams and their association with the textural quality of “boiled yam,” arguably the most common food product from yams, were studied using six varieties with variable cooking qualities from each of the two species, Dioscorea alata L. and D. rotundata Poir. Histological studies on raw yams showed parenchyma cells of both species to be three-dimensional and polyhedral in shape, with starch granules loosely arranged in D. rotundata but densely packed in D. alata. Generally, there was cell separation and rounding off of cells in cooked yams of D. rotundata varieties, whereas cell separation was only partial with no rounding off in D. alata . Mealy boiled yams showed complete cell separation and the “rounding off” phenomenon, whereas the waxy ones showed partial retention of textural cell integrity. These relative changes in microstructure of yam when boiled could serve as indicators of textural quality in boiled yam. [ABSTRACT FROM AUTHOR]

The objective of the present work was to develop a method to distinguish between metabolically inactive and active parts of plant roots. White clover (Trifolium repensL.) roots were stained with 2,3,5-triphenyltetrazolium chloride (TTC) followed by root colour classification with an interactive scanner-based image analysis programme (WinRHIZO). Roots inactivated by boiling were unstained and pale brown, whereas fresh samples with predominantly metabolically active roots turned dark red, red or pale red after staining. A small amount of very young, presumable active roots (0.8% of total active root length) failed to stain red with TTC. The colour analysis of inactive and active roots was based on four colour classes for boiled roots and seven classes for fresh roots, respectively, as defined upon visual examination of images. Pixel colours falling outside the defined classes were allocated to the nearest defined class - an option that increased objectivity and stability and reduced the required number of colour classes. For the fresh white clover roots, 75-86% of the total root length was determined as active, while 3-7% of the boiled roots fell into the same category. The percentage of total root length measured by WinRHIZO that was identified as metabolically active was linearly correlated with the percentage of fresh roots in mixtures of fresh and boiled roots (R2=0.99). Colour classes chosenà priorifrom one experiment could be used to distinguish fairly satisfactorily between active and inactive roots of another white clover cultivar grown under other conditions, but failed to classify activity in ryegrass (Lolium multiflorumLam.) root samples. In the latter case, colour classes needed to be re-defined in order to produce reliable data. Our work shows that WinRHIZO’s colour identification sub-module provides a new promising tool to classify root activity as identified after staining with TTC, but colour classes must be carefully evaluated on every new occasion. [ABSTRACT FROM AUTHOR]

The sales of fermented, roasted and boiled bamboo shoots in the market places of Arunachal Pradesh, Manipur, Meghalaya, Nagaland and Sikkim, of the North-Eastern Himalayan (NEH) region, India have been reported. The results are based on the survey of 118 markets covering 1200 primary and secondary vendors from 51 districts of NEH region. The consumption of fermented, roasted and boiled shoots was estimated to be ca. 680 tonnes; the highest occurs in Arunachal Pradesh (481 tonnes/year) and the lowest in Nagaland (19.5 tonnes/year). The bamboo shoots are consumed in the form of fermented-slice, crushed-fermented moist, crushed-fermented dry, fermented whole shoot, roasted whole shoot and boiled whole shoot in different states of the region. Cost–return analysis for sales of these bamboo products revealed a net income of 23 million rupees per annum (US$ 502 950) from the entire region with the highest (17.5 million rupees/year or US$ 38 270) in Arunachal Pradesh and the lowest in Sikkim (0.47 million rupees/year or US$ 10 280). Employment opportunities have also been worked out and ca. 1260 persons/year could earn their subsistence through selling of bamboo shoot products. [ABSTRACT FROM AUTHOR]

Salmonella enteritidiswas cultivated in egg yolks and submitted to boiling and frying methods commonly used in domestic conditions in the south of Brazil. The results have demonstrated a rapid growth of the microorganism reaching counts of 9.0 log 10 at 168 h. When contaminated shell eggs were placed in water and slowly heated, a population of approximately 7.0 log 10 was completely inactivated after boiling for 1 min. However, in eggs placed directly in boiling water, the reduction was only 1.35 log 10 after 1 min, and the entire population was eliminated after 3 min. A reduction of approximately 2.78 log 10 was observed after frying for 1.5, 2.0 and 2.5 min. Even though the solidification of yolk has been pointed out as an indicator ofS. enteritidiselimination in egg yolks, attention should be given to frying procedures, as considerable high levels of this microorganism could be recovered even from solidified yolks. [ABSTRACT FROM AUTHOR]

The fate of B-aflatoxins was studied during the toasting and boiling of contaminated maize. One lot of aflatoxin-free grain served as the control Lot 1 (L1). Lot 2 (L2) and Lot 3 (L3) had aflatoxin concentrations of 120.7 and 575.0 μg kg−1. In the case of contaminated pinole-powder, the aflatoxin content was 22.9 for L2 and 171.0 μg kg−1 for L3 and, after atole preparation (a Mexican porridge-like drink), the aflatoxin content was 9.7 and 68.2 μg kg−1 for L2 and L3, respectively. According to these results, higher reductions in mycotoxin levels were achieved during the toasting process and only a moderate extra-reduction occurred during the boiling process. [Copyright &y& Elsevier]