Impact of infrared finishing on the mechanical and sensorial properties of wheat donuts

Infrared radiation may be used to simulate an immersion frying heat flux and create products with fried-like textures but lower fat contents. The objective of this study was to determine the process parameters needed to produce partially-fried, infrared-finished donuts comparable to fully-fried (control) donuts. A total of 8 different sets of infrared oven parameters (emitter height and belt speed) were tested. Instrumental analysis showed that all infrared-finished donuts had significantly (P≤ 0.05) lower fat content (25.6% to 30.6%) than the control (33.7%). Setting the infrared emitters in a height gradient from 70 to 50 mm or at a constant height of 60 mm above the belt produced donuts that were most instrumentally similar to the control. Infrared-finished donuts had comparable (P≤ 0.05) overall acceptance scores to the control, 5.28 to 5.85 versus 5.83, respectively. Infrared radiation may be used to finish-fry partially-fried donuts, yielding a product similar to a fully-fried donut but with significantly lower fat content. Practical Applications: The partial-frying, infrared-finishing process detailed in this article may be used for other deep-fried foods. It is likely that these foods will also have a lower fat content when prepared with this process than when they are deep-fried. This process provides a method of lowering the fat content of fried foods without changing the food formulation.     

Comparison of analytical and predictive methods for water,protein, fat,sugar, and gross energy in marine mammal milk

Mammalian milks may differ greatly in composition from cow milk, and these differences may affect the performance of analytical methods. High-fat, high-protein milks with a preponderance of oligosaccharides, such as those produced by many marine mammals, present a particular challenge. We compared the performance of several methods against reference procedures using Weddell seal (Leptonychotes weddellii) milk of highly varied composition (by reference methods: 27–63% water, 24–62% fat, 8–12% crude protein, 0.5–1.8% sugar). A microdrying step preparatory to carbon-hydrogen-nitrogen (CHN) gas analysis slightly underestimated water content and had a higher repeatability relative standard deviation (RSD_r) than did reference oven drying at 100°C. Compared with a reference macro-Kjeldahl protein procedure, the CHN (or Dumas) combustion method had a somewhat higher RSD_r (1.56 vs. 0.60%) but correlation between methods was high (0.992), means were not different (CHN: 17.2 ± 0.46% dry matter basis; Kjeldahl 17.3 ± 0.49% dry matter basis), there were no significant proportional or constant errors, and predictive performance was high. A carbon stoichiometric procedure based on CHN analysis failed to adequately predict fat (reference: Röse-Gottlieb method) or total sugar (reference: phenol-sulfuric acid method). Gross energy content, calculated from energetic factors and results from reference methods for fat, protein, and total sugar, accurately predicted gross energy as measured by bomb calorimetry. We conclude that the CHN (Dumas) combustion method and calculation of gross energy are acceptable analytical approaches for marine mammal milk, but fat and sugar require separate analysis by appropriate analytic methods and cannot be adequately estimated by carbon stoichiometry. Some other alternative methods—low-temperature drying for water determination; Bradford, Lowry, and biuret methods for protein; the Folch and the Bligh and Dyer methods for fat; and enzymatic and reducing sugar methods for total sugar—appear likely to produce substantial error in marine mammal milks. It is important that alternative analytical methods be properly validated against a reference method before being used, especially for mammalian milks that differ greatly from cow milk in analyte characteristics and concentrations.     

Measurement of anthocyanins and other phytochemicals in purple wheat

The major anthocyanin composition of normal purple wheat and heat stressed purple wheat were measured using HPLC, LC–MS/MS and the pH differential method. The lignan secoisolariciresinol diglucoside (SDG) and melatonin content were also measured. Total anthocyanin profile of normal purple wheat (491.3 mg/kg) was significantly (P < 0.05) lower than that of the heat stressed purple wheat (522.7 mg/kg). Thirteen major anthocyanins were isolated and cyanidin 3-glucoside was the predominant anthocyanin in purple wheat. Using the pH differential method, the total anthocyanin content of normal (500.6 mg/kg) and heat stressed (526.0 mg/kg) purple wheat were similar to those observed using HPLC. The SDG content of normal and heat stressed purple wheat were 770 and 520 μg/kg, while melatonin content was 4 and 2 μg/kg, respectively. The presence of SDG and melatonin in addition to anthocyanins may contribute to the health benefits associated with consumption of coloured cereal grains.     

Physicochemical characterisation of dietary fibre components and their ability to bind some process-induced mutagenic heterocyclic amines,Trp-P-1, Trp-P-2, AαC and MeAαC

The physicochemical properties of potato fibre, wheat bran and oat samples were investigated, along with their binding capability to heterocyclic amines (HCAs). Potato fibre displayed highest total dietary fibre content (71.8/100 g dry weight basis, dwb), followed by wheat bran (57.2/100 g dwb) and oat sample 2 (53.0/100 g dwb). Oat samples 1, 3 and 4 displayed considerably lower dietary fibre content (20.5–28.8/100 g, dwb). Oat samples 3 and 4 displayed highest soluble fibre content (70–83%), and oat sample 3 also displayed highest swelling and water retention capacity (WRC). Dietary fibre samples, except samples 3 and 4, displayed improved binding to HCAs as sample weight increased. The behaviour of wheat bran and potato fibre was similar to oat samples 1 and 2. Binding of MeAαC was comparatively greater than that of other HCAs. Dietary fibre fractions with high insoluble fibre and functional groups of HCAs may significantly contribute to the binding capacity.     

Extraction of ginsenosides from a blend of wheat flour and ginseng powder

This study explored conditions for maximum extraction of ginsenosides (G) from a blend of wheat flour (WF) and ginseng powder (GP). WF (0.9 g), GP (0.1 g), or WF–GP (0.9 g WF + 0.1 g GP) was mixed with distilled water (4.5, 0.5, or 5.0 ml, respectively) and heated at temperatures from 25 to 90 °C. Individual G (Rb1, Rc, and Rd) were fractionated and identified by RP-HPLC. Interactions between WF components and G, including interactions between the wheat starch fraction (SF) and G and between the gluten fraction (GF) and G, were observed in WF–GP heated at 90 °C. The degree of interactions between the SF and G was greater than that between the GF and G. The interactions between WF components and G decreased the amounts of G extractable from the heated WF–GP. The interactions between WF components and G could be disrupted by increasing ultrasonic extraction time to 90 min for maximum extraction.     

Aflatoxin contents of stored and artificially inoculated cereals and nuts

Aflatoxin contents of cereals and nuts, collected from local markets of NWFP, were determined by thin layer chromatography (TLC). The seeds of these crops were also inoculated with Aspergillus flavus and the aflatoxin content and its relation with the proximate composition of seeds was studied. The effect of storage for different durations of time (2–3 and 12–18 months) on the aflatoxin content of seeds was also assessed. Aflatoxin content of cereals (wheat, maize and rice) ranged from 14 to 45 μg/kg, and that of nuts (almond, walnut and peanut) varied from 5 to 17 μg/kg. The aflatoxin content was within the safe limit (50 μg/kg) recommended by FAO. The aflatoxin content of inoculated seeds was significantly (p < 0.05) increased over control (un-inoculated seeds). This was positively related (r = 0.65) to moisture content of the seeds. However, negative correlation (r = −0.50) existed between aflatoxin and ash contents of the seeds. Protein, fat and total carbohydrate (NFE) contents were not much affected by inoculation. Prolonged storage for 18 months (1.5 years) significantly (p < 0.05) increased aflatoxin contents of seeds compared to short storage periods (2–3 months). It was concluded that aflatoxin content of food should be monitored to ensure food safety. Prolonged storage of cereal and nuts in warm humid condition should be avoided to minimize the risk of aflatoxin contamination.     

Nutritional assessment of cookies supplemented with defatted wheat germ

Replacement of wheat flour with defatted wheat germ (DFWG) at levels of 0–25% was investigated for its effect on functional and nutritional properties of cookies. The crude protein content of DFWG was as high as 27.8% with a highly valuable amino acid profile, rich in essential amino acids, especially lysine (2.32 g/100 g). The physicochemical and sensory evaluation of cookies, revealed that up to 15% substitution of wheat flour with DFWG produced acceptable cookies similar to the control (100% wheat flour) cookies. The protein quality of the cookies was assessed through weanling albino rats by feeding a diet of cookies for 10 days, which was formulated to supply 10% protein, with a casein diet as a control. The cookies containing 15% DFWG, were best regarding protein bioavailability in rats. The protein efficiency ratio (PER), net protein utilization (NPU), biological value (BV) and true digestibility (TD) differed significantly among diets containing cookies with 0–10% DFWG, and casein diet when fed to rats. Diets containing 15% DFWG have values, of these parameters, similar to the casein diet.     

Computational fluid dynamics (CFD) modeling of an electrical heating oven for bread-baking process

Radiation is the most dominant heat transfer mode in an electrical heating oven. A 3D CFD model for an electric heating baking oven was developed. Three different radiation models namely, discrete transfer radiation model (DTRM), surface to surface (S2S) and discrete ordinates (DO) were employed for the simulation of the electrical baking oven. All models predicted almost similar results, which tallied well with the experimental measurements. During the full heating cycle, the oven set-point temperature was reached after 360 s. Lower temperature zones occurred near oven wall due to lower air flow. Based on preliminary evaluation of applicability, the DO radiation model was selected for bread baking simulation and validated with the experimental measurement of bread temperature. Bread simulation was carried out to study the profiles of temperature and starch gelatinization of crust and crumb of the product. This study indicated the baking process to be complete at 1500 s when the temperature of bread-center reached 100 °C.     

Effect of sodium chloride replacement and apple pulp inclusion on the physico-chemical, textural and sensory properties of low fat chicken nuggets

The effect of 40 percent sodium chloride replacement with salt substitute blend (potassium chloride, citric acid, tartaric acid and sucrose) and incorporation of apple pulp, at the levels of 8 (Treatment I), 10 (Treatment II) and 12 (Treatment III) g/100 g of formulation, on the various quality characteristics of low fat chicken nuggets was investigated. Emulsion and product pH values were significantly higher (P < 0.01) for the control when compared to treatments. Salt replacement and apple pulp addition resulted in significantly lower (P < 0.05) emulsion stability and cooking yield. Among low salt and low fat nuggets, the product with 12 g/100 g apple pulp had the highest moisture percent. Protein and ash contents were significantly lower (P < 0.01) in treatment products, whereas moisture protein ratio was higher. Incorporation of apple pulp significantly increased (P < 0.01) dietary fibre content, redness, yellowness and chroma index of the product. Textural properties of the products significantly decreased (P < 0.01) with substitution of common salt and addition of apple pulp. Sensory evaluation showed significant reduction (P < 0.01) in texture and overall acceptability scores of treatment products; however, scores were in the range of very good.     

Chemical characteristics,fatty acid composition and conjugated linoleic acid (CLA) content of traditional Greek yogurts

Many studies with conjugated linoleic acid (CLA) indicate that it has a protective effect against mammary cancer. Because dairy products are the most important dietary sources of CLA, we have investigated the CLA concentrations and additionally the fatty acid profiles and chemical composition of several commercial, traditional, Greek yogurts from different geographical origin. The fat content of yogurts was in the order of goat < cow < sheep. Cow, sheep and goat milk yogurts contain respectively 0.128–1.501, 0.405–1.250 and 0.433–0.976 g CLA/100 g fat. Low-fat milk yogurts showed lower values of c-9, t-11 CLA content on lipid basis compared to full-fat yogurts. Samples from mountain areas showed average c-9, t-11 CLA content higher than those from prairie districts. The highest amounts of saturated fatty acids (SFA) were found in low-fat yogurts, of monounsaturated fatty acids (MUFA) in sheep milk yogurts and of polyunsaturated fatty acid (PUFA) in low-fat cow milk yogurts.     

Amaranthus hypochondriacus and Amaranthus caudatus germplasm: Characteristics of plants,grain and flours

In the present study, the plant, grain and flour characteristics of 48 Amaranthus hypochondriacus and 11 Amaranthus caudatus lines are reported. A. hypochondriacus grains had a higher thousand kernel weight (0.62–0.88 g), a creamish yellow colour (L∗ = 61.38–68.29, b∗ = 5.26–6.8 and a∗ = 19.71–23.84), whereas A. caudatus grains had a lower thousand kernel weight (0.46–0.70 g) and a reddish-brown colour (L∗ = 47.1–51.2, b∗ = 11.82–14.02 and a∗ = 7.72–13.29). The A. caudatus lines had a higher protein content, fat content and tendency for retrogradation, and lower α-amylase activity as compared to A. hypochondriacus lines. The Amaranthus lines with higher a∗-values and lower thousand kernel weight, L∗- and b∗-values, had a higher fat, crude fibre and protein content. The correlation of fat and crude fibre content with the thousand kernel weight, L∗-, a∗- and b∗-values, was significant. The A. hypochondriacus lines showed higher pasting temperature, and lower peak viscosity, breakdown and setback, as compared to the A. caudatus lines. The result reflected that the lines with higher α-amylase activity showed a lower peak viscosity, breakdown, final viscosity and gel hardness, and a higher pasting temperature.     

Effectiveness of oxygen barrier oven bags in low temperature cooking on reduction of warmed-over flavor in beef roasts

A 3 × 3 × 2 factorial was utilized to determine if roast size (small, medium, large), cooking method (open-pan, oven bag, vacuum bag), and heating process (fresh, reheated) prevented warmed-over flavor (WOF) in beef clod roasts. Fresh vacuum bag and reheated open-pan roasts had higher cardboardy flavor scores compared with fresh open-pan roast scores. Reheated roasts in oven and vacuum bags did not differ from fresh roasts for cardboardy flavor. Brothy and fat intensity were increased in reheated roasts in oven and vacuum bags compared with fresh roasts in oven and vacuum bags. Differences in TBARS were found in the interaction of heating process and roast size with the fresh and reheated large, and reheated medium roasts having the lowest values. Based on TBARS data, to prevent WOF in reheated beef roasts, a larger size roast in a cooking bag is the most effective method.     

In-home consumer and shear force evaluation of steaks from the M. serratus ventralis thoracis

The M. serratus ventralis thoracis was obtained from US Select arm chucks (n = 87) to investigate if this underutilized muscle can be used as a steak alternative. Muscles were assigned randomly into three treatment groups: (1) control; (2) blade tenderization; and (3) injection, containing salt, phosphate, and papain. Steaks were cut from each muscle for in-home consumer evaluation (n = 136) and Warner–Bratzler shear (WBS) force determination. The WBS values for injected steaks (13.1 N) were lower (P < 0.05) than for blade-tenderized (18.4 N) and control (19.9 N) steaks. Tenderness ratings for the injected steaks were higher (P < 0.05) compared to the other treatments when steaks were grilled, oven prepared or were cooked in a skillet; however, this improvement did not significantly influence overall like scores for steaks that were oven prepared or cooked in a skillet. For the most part, degree of doneness did not significantly impact consumer evaluations of steaks prepared by the various cooking methods. However, there was a treatment × degree of doneness interaction for grilled-cooked steaks where increased doneness for blade-tenderized and injected steaks resulted in increased palatability ratings, whereas increased doneness for control steaks generally resulted in lowered palatability ratings. Consumer ratings and WBS values for the M. serratus ventralis thoracis indicate that merchandising steaks from this muscle may be a viable option in the marketplace, especially if blade tenderization or injection processes are used for further enhancement.     

Development of Low Oil-Uptake Donuts

ABSTRACT: Reduced oil donuts are one goal of the do nut industry. In this investigation, donuts were developed using wheat flour and various additives. Donut properties were analyzed including dough consistency (DC), firmness (FN), moisture content (MC), and oil uptake (OU). Replacement of wheat flour with long-grain or waxy rice flour resulted in lower DC and MC, and higher FN and OU. Replacement with gelatinized rice flour or acetylated rice starch resulted in generally higher DC, MC and FN and lower OU. Donuts formulated with wheat flour and up to 50% gelatinized rice flour were comparable to wheat donuts in general characteristics but as much as 64% lower in oil uptake.     

Hard Red Spring wheat/C-TRIM 20 bread: Formulation,processing and texture analysis

C-TRIM, a β-glucan-rich fraction, was added to Hard Red Spring wheat (HRSW) flour to increase soluble fiber content of bread, and to obtain a minimum of 0.75 g/bread serving (0.75 g/30 g or 2.5%) required by FDA for health claim. Three treatments or blends FGT0 (100% wheat flour – control), FGT1 (58% flour, 25% gluten and 17% C-TRIM) and FGT2 (60% flour, 22.5% gluten, and 17% C-TRIM) were used in the study. The total amount of soluble fiber from C-TRIM in FGT1 and FGT2 was 4.07–4.17% which was more than the amount required by FDA. The presence of C-TRIM increased both, the Farinograph water absorption and the arrival time. The dough mixing tolerance index (MTI) was also increased by C-TRIM. The FGT1 had higher stability than FGT2, whereas, the loaf volume of FGT1-B was also significantly higher than FGT0-B control and FGT2-B bread. The DSC results indicated that the amount of freezable-water in C-TRIM treated bread (FGT1-B and FGT2-B) was significantly higher than the control wheat flour bread (FGT0-B). This may be attributed to the higher amount of water absorbed by C-TRIM during bread dough (FGT1-D and FGT2-D) preparation and trapped or bound within the bread matrix after baking as compared to the control. After storage of FGT0-B, FGT1-B, and FGT2-B breads 2, 5, and 7 days storage at 25 °C, 4 °C, and −20 °C, the texture of bread were measured with a Texture Analyzer and the data analyzed statistically. The FTG0-B control bread firmness was significantly higher than FGT1-B and FGT2-B C-TRIM treated breads after 7 days storage at 25 °C. The amount of 0.1 M acetic acid-extractable protein was lower in FGT1-B than the control wheat flour (FGT0-B) sample. In addition, more protein was extracted at pH 7.0 than pH 4.5 because of less charges at neutral pH than pH 4.5. The free zone capillary electrophoresis analysis showed obvious differences in the protein charge and size between the dough and bread.     

Yeast leavened banana-bread: Formulation,processing, colour and texture analysis

Banana powder (BP) was added to hard-red spring wheat (HRSW) flour intended for yeast-leavened bread formulation. Five different formulations containing 10%, 15%, 20%, 25%, and 30% BP were prepared with varying amounts of base flour, while vital gluten was maintained at 25% in all blends. Based on the added BP amounts only, the prepared bread could deliver 42.87–128.6 mg potassium/30 g of bread (one regular slice) and 0.33–1.00 g of fibre. Although the dough water absorption was increased, due to BP addition, the dough mixing tolerance (MTI) decreased. The bread loaf volume was significantly higher than the control except for the 30% blend, where the loaf volume was similar to the control. Bread staling increased with BP levels due to the high sugar content but, this effect was limited to the first two days of storage. Blends exhibited darker colour due to the high sugar and protein, while the 25% and 30% blends had the lowest percent of freezable water. The amounts of acetic acid extractable proteins from the dry blends and the dough decreased with increase in BP. The linear rheological properties of the control, 10%, and 30% blends exhibited similar viscoelastic solid behaviour, where both G′ and G′′ had plateaus (G′ > G′′) and they were parallel to each other over three decades of the frequency. Blends showed higher moduli values than the control.     

The influence of γ-irradiation on some biological activities and electrophoresis patterns of wheat grain albumin fraction

Water-soluble proteins were extracted from irradiated wheat grain for the purpose of assaying biological activities, reducing sugars content and SDS–PAGE electrophoresis. The differences between samples after γ-irradiation were tested by analysis of variance at the level of significance (P ? 0.05). Ionising radiation (0.05–10 kGy) caused an increase in the activity of endogenous amylases, statistically significant at doses of 5 and 10 kGy (P ? 0.05), which was well correlated with the highest extractable protein content. γ-Irradiation of wheat grain at a dose of 0.05 kGy caused an increase of inhibition activity against Sitophilus granarius L. α-Amylase, whereas there was a decrease at 10 kGy (P ? 0.05). On the other hand, grain irradiated by 0.5 and 1 kGy doses showed a significant increase in inhibition activity against α-amylase of Tribolium confusum Duv. (P ? 0.05) while at the remaining doses the inhibition activity was on the same level as the control grain. Decrease of Ephesitia kuehniella Zell. α-amylase was observed only at 5 kGy radiation dose (P ? 0.05). At the remaining doses this activity was comparable to non-irradiated grain.     

Enzymatic and fluorometric determination of triacylglycerols in cow milk and other opaque matrices

The fat content of milk is an important indication of quality, both economically and physiologically. Existing analytical methods of milk fat are based on physical determination, i.e. gravimetric determination or near infrared spectroscopy (IR). Triacylglycerols (TAG) constitute up to 98% of total fat in milk. The present study describes a new method for determination of triacylglycerols in milk. The present method is a chemical, i.e. enzymatic–fluorometric assessment of glycerol, the content of TAG is consequently given in mol per litre. The method demonstrates a good accuracy and precision and the correlation with standard IR methods shows a fine association between the different assessment methods (n = 228; r = 0.905). Fatty acid profiles of sixty individual milk samples indicate that parameters co-linearly connected to specific fatty acids may explain a considerable amount of the variation between the methods. Furthermore, discrepancies between the present method and the established IR method may partly be due to the fact that IR spectroscopy is calibrated individually against gravimetric methods not taking fatty acid profiles and thereby molar weight of TAG into account.     

Impact of Infrared Broiling on the Thiamin and Riboflavin Retention and Sensory Quality of Salmon Steaks for Foodservice Use

Salmon steaks were broiled using infrared radiation and compared to convection oven baking. Total percent cooking losses of moisture and fat content were not significantly different. Samples broiled by infrared oven retained 87.2% and 92.6% of thiamin and riboflavin content, respectively. There were no significant differences for vitamin retention by both methods. Appearance and color of salmon steaks baked in the convection oven were rated significantly higher than infrared broiled samples. Tenderness and juiciness scores for infrared broiled steaks were significantly higher than those for convection oven baked steaks. There were no significant differences in panel scores for odor, flakiness, flavor and overall acceptability of steaks prepared by both methods.     

Baking kinetics of muffins in convection and steam assisted hybrid ovens (baking kinetics of muffin…)

Effects of oven type and baking temperature on acrylamide concentration, surface browning, temperature profiles and drying rates of muffins were investigated. Muffins were baked in convection and steam assisted hybrid ovens at 145, 160 and 175 °C for different baking times. For all oven types, the acrylamide concentration of muffins increased with increasing baking time and temperature (p < 0.05). The formation was considered as the first order reaction kinetics except for the lowest baking temperature at natural convection and steam assisted hybrid ovens. The reaction rate constant, k was found to be in the range of 0.027–0.078 (min⁻¹). For the forced convection oven, the effect of baking temperature on acrylamide concentration followed the Arrhenius type of equation; with activation energy of 36.35 kJ/mol. The minimum drying rate was observed by the steam assisted hybrid oven, at all conditions. Steam assisted baking resulted in lower acrylamide concentration at all baking temperatures, while providing the average moisture content not significantly different.