Effect of flaxseed processing on its true metabolizable energy values for adult chicken

The objective of the present experiment was to study the effect of flaxseed processing on nitrogen corrected true metabolizable energy (TME_n) values for adult roosters. Flaxseed was processed as pelleted, autoclaved or microwave roasted. Leghorn roosters were used for the TME determination procedure. The TME_n value of flaxseed batch A, 14.48 MJ kg^?1 DM, was significantly (P < 0.05) increased to 17.89 MJ kg^?1 DM by three‐time repeat‐pelleting, or to 18.07 MJ kg^?1 dry matter (DM) by autoclaving, respectively. Microwave roasting also significantly (P < 0.05) increased the TME_n value of flaxseed batch B by 22%. The TME_n improvement observed due to processing was accompanied by increased ether extract utilization. The apparent ether extract digestibility of flaxseed batch A, 61.2%, was very significantly (P < 0.01) increased to 81.5 and 83.2% by processing as repeat‐pelleting and autoclaving, respectively. Microwave roasting also significantly (P < 0.05) increased the apparent digestibility of ether extract for flaxseed batch B from 49.1 to 64.4%. Proper flaxseed processing as pelleting, autoclaving and microwave roasting led to higher TME_n values for Leghorn roosters, mainly as the result of increased ether extract utilization. Copyright © 2004 Society of Chemical Industry     

Chemical,nutritive, deoxynivalenol and zearalenone content of corn relative to the site of inoculation with different isolates of Fusarium graminearum

Kernels from two samples of 18 ears of corn were hand-shelled into three fractions (Fl, F2 and F3) relative to the site (F3) where the ears had previously been inoculated with one of four isolates of Fusarium graminearum (Schwabe). F3 and Fl were from the nearest and remotest parts of the ear, respectively, to the inoculation site. Ears of uninoculated control corn were processed in the same manner. The resulting 30 samples were analysed, after grinding (20 mesh), for deoxynivalenol (DON), zearalenone (ZEA), ergosterol (EGS), dry matter (DM), 200 kernel weight, Kjeldahl nitrogen (N), ether extract, ash, sugar, starch, acid and neutral detergent fibre (ADF, NDF, respectively), cellulose, hemicellulose and lignin. The true metabolisable energy (TME), TME corrected to zero N balance (TME_n), true available amino acid (TAAA) and true DM digestibility (TDMD) contents of these samples and corn to which 4, 16 or 64 mg purified DON kg^?1 were added, were determined using adult White Leghorn chickens. The DON, ZEA, EGS, N and ash contents were higher (P<0.001), and ether extract, TME and TME_n values were lower (p<0.01) in F3 than in Fl. Higer avilabilites accured for aspartic and glutamic acids, isoleucine, leucine and histidine in F2 and F3 than F1 (P<0.05). Carbohydrate and fibre values varied little (p>0.05) among fractions either within or among incoulation treatments. Sources of Fusarium inoculate influenced (P<0.05) the DON, ZEA, N, fat and TDMD of the corn. The TME_n and total TAAA of corn decreased (P<0.001) when purified DON was added. Moderate relationships (r=0.57?0.73) occurred between DON and ZEA, EGS and N. In general, these results are similar to those for wheat, and indicate that chemical and nutritive content of feedingstuffs may be increased when they are infected by toxigenic fungi.     

Influences of Superheated Steam Roasting and Water Activity Control as Oxidation Mitigation Methods on Physicochemical Properties,Lipid Oxidation,and Free Fatty Acids Compositions of Roasted Rice

The feasibility of using superheated steam roasting and wetting to control the water activity in an optimal range to mitigate oxidation of roasted rice was evaluated. Changes in the bed temperature as well as rice kernel moisture content, water activity, and color were monitored during fluidized bed roasting with superheated steam and hot air at 170, 190, and 210 °C. Air‐roasted rice was rewetted to raise its water activity to 0.30 to 0.35. All the samples were analyzed for the total oil content, peroxide value (PV), thiobarbituric acid (TBA) value, and free fatty acids (FFA) content and compositions. Higher roasting temperatures, especially at 210 °C, led to a significant increase (P ≤ 0.05) in the total oil content of the roasted rice. Wetting led to a significant (P ≤ 0.05) decrease in the TBA value of the air‐roasted rice, although the total FFA content significantly (P ≤ 0.05) increased. Rice roasted in superheated steam at 210 °C exhibited significantly (P ≤ 0.05) lower PV and TBA value; their total FFA content also tended to decrease, which is desirable for a longer shelf life.     

Optimization of Hull‐Less Pumpkin Seed Roasting Conditions Using Response Surface Methodology

Abstract: Response surface methodology (RSM) was applied to optimize hull‐less pumpkin seed roasting conditions before seed pressing to maximize the biochemical composition and antioxidant capacity of the virgin pumpkin oils obtained using a hydraulic press. Hull‐less pumpkin seeds were roasted for various lengths of time (30 to 70 min) at various roasting temperatures (90 to 130 °C), resulting in 9 different oil samples, while the responses were phospholipids content, total phenols content, α‐ and γ‐tocopherols, and antioxidative activity [by 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH) free‐radical assay]. Mathematical models have shown that roasting conditions influenced all dependent variables at P < 0.05. The higher roasting temperatures had a significant effect (P < 0.05) on phospholipids, phenols, and α‐tocopherols contents, while longer roasting time had a significant effect (P < 0.05) on γ‐tocopherol content and antioxidant capacity, among the samples prepared under different roasting conditions. The optimum conditions for roasting the hull‐less pumpkin seeds were 120 °C for duration of 49 min, which resulted in these oil concentrations: phospholipids 0.29%, total phenols 23.06 mg/kg, α‐tocopherol 5.74 mg/100 g, γ‐tocopherol 24.41 mg/100 g, and an antioxidative activity (EC₅₀) of 27.18 mg oil/mg DPPH. Practical Application: A well‐defined roasting process is very important for the food industry to be able to produce pumpkin seed oil with desirable nutritive and chemical characteristics of this unique salad oil, which changes during the roasting. This study contributes to the knowledge of a product design process for the roasting conditions of naked pumpkin seeds based on results that have demonstrated that an increase in roasting temperature significantly increased the biochemical values and antioxidant properties of the obtained virgin oils.     

The effect of roasting on the nutritional and antioxidant properties of yellow and white maize varieties

Maize varieties (yellow and white) were roasted for 17 min; and allowed to cool, and later milled into powder. The nutritional evaluation (proximate composition, mineral and antinutrient content determination) and antioxidant properties investigation (reducing power, free radicals scavenging ability and Fe²⁺ chelating ability) of the product was subsequently carried out. The result of the study revealed that roasting caused a significant increase (P < 0.05) in the crude fat, carbohydrate, Ca, Na, Mg and Zn content. Conversely, a significant decrease (P < 0.05) was observed in crude protein, crude fibre, Fe and K content. A significant decrease in the phytate content was also observed. However, the reduced phytate content did not have sparing effect on Zn bioavailability. Roasting significantly (P < 0.05) reduced the extractible phenol and flavonoid content of the maize varieties. The antioxidant properties (1,1‐diphenyl‐2‐picrylhydracyl free radical scavenging ability and Fe²⁺ chelating ability) followed the phenolic content pattern. However, roasting caused a significant increase in the ferric reducing antioxidant power of the maize varieties. Thus, roasting reduced the protein content of maize but also increased the energy value and antioxidant capacity as exemplified by high reducing power.     

Effect of malting conditions and quality characteristics of malt and roasted malt extract from ‘acha’ grains (Digitaria exilis Stapf)

BACKGROUND: Considering the importance of malting and roasting on the quality of ‘acha’ beverages, a study was conducted to find optimum conditions for malting and the production of a high‐quality roasted extract that could be used for an ‘acha’ beverage. RESULTS: The data obtained were analysed using response surface methodology. The results revealed that the most significant (P < 0.05) malting factors that affect the response variables were the linear terms of germination time and drying temperature. However, for the extract production, the linear term of roasting temperature was the most significant (P < 0.05) factor. The quadratic and interaction terms exhibited significant (P < 0.05) effect in all cases apart from the flavour. CONCLUSION: The overall optimum regions were established at 28 h of germination time, 55 °C drying temperature and 5.0% moisture content for the malting conditions while for the extract production, a roasting temperature of 210 °C, extraction temperature of 70 °C and extraction duration of 20 min were established. Copyright © 2010 Society of Chemical Industry     

Effect of roasting parameters on soy‐butter product quality

Effect of roasting temperature and time on the hardness, moisture content and colour of whole‐kernel of soybean was studied using response surface method (RSM). Colour of reference soy‐butter (RSB) was used to indicate the time and temperature suitable for roasting soybean kernels to prepare soy‐butter (SB). Temperature (160 °C) and time (90 min) for roasting were identified, soybean kernels were roasted, subsequently made into SB and compared with RSB on the basis of nutrient content, particle size, colour and rheology. SB contained 45 g% protein and 34 g% fat on dry matter basis. There was a significant difference (P < 0.05) between RSB and SB on the basis of L* values, D_3,2 and D_4,3. Rheology showed that SB samples behaved like a viscoelastic material. The mean apparent viscosity was significantly different (P < 0.0001) between SB (7.18 Pa.s) and RSB (4.72 Pa.s) which may be due to the significant difference in the particle size distribution (PSD). The Herschel‐Bulkley model could successfully explain the rheological behaviour of SB.     

Effects of roasting on ruminal nutrient degradability of sunflower seed

A study was conducted to determine the effects of roasting sunflower seed using heated particulate medium (heated salt at 250 °C, 60 s contact of salt and sunflower seed and 120 s holding time) on crude protein (CP) fractions, ruminal dry matter (DM) and CP degradabilities, and ruminal disappearance of amino and fatty acids. Two ruminally fistulated cows were used in a randomised complete block design. Roasting of sunflower seed decreased (P < 0.05) soluble protein and increased (P < 0.05) neutral detergent‐insoluble protein with little effect on acid detergent‐insoluble protein. Results of the in situ nylon bag study showed that roasting decreased (P < 0.05) ruminal degradability of DM and CP and increased (P < 0.05) ruminal undegraded CP of sunflower seed. Roasting increased (P < 0.05) intestinal digestibility of ruminal undegraded protein. Ruminal disappearance of all amino acids (following 12 h of incubation) was greater (P < 0.05) for raw than for roasted sunflower seed. Similar results were also observed for ruminal disappearance of fatty acids. It was concluded that roasting of sunflower seed using heated salt decreased ruminal nutrient degradabilities and thus increased the concentrations of amino acids and polyunsaturated fatty acids available for digestion in the small intestine. Copyright © 2003 Society of Chemical Industry     

Nutritional and physicochemical evaluations of tahina (sesame butter) prepared from heat‐treated sesame seeds

Dehulled sesame seeds were roasted using different heat treatments. The effects of roasting treatments on the nutritive value, physicochemical properties and sensory properties of produced tahina were studied. Resultant tahina contained 586–594 g kg⁻¹ crude oil, 219–226 g kg⁻¹ crude protein and <30 g kg⁻¹ crude fibre and ash. Crude protein, crude fibre, ash and N‐free extract in tahina samples were not affected by roasting treatments. However, crude oil was decreased by steam roasting and hot plate roasting. Hot plate roasting was more effective in reducing raffinose content than other roasting treatments, whereas vacuum roasting was less effective in reducing raffinose content than other roasting treatments. Tahinas were good sources of essential amino acids, especially sulphur‐containing amino acids, aromatic amino acids and tryptophan. Hot air roasted tahina followed by vacuum roasted tahina had higher total essential amino acid contents than steam roasted and hot plate roasted tahinas. Lysine was the first limiting amino acid in tahinas. Tahinas had a relatively high in vitro protein digestibility (over 83%). Tahina is a good source of niacin. Hot air roasted tahina had the highest content of B group vitamins compared with other tahina samples. Resultant tahinas had relatively high amounts of Na, Mg, K, Cu, Zn and Fe and a low amount of Ca. Roasting treatments did not affect the mineral contents. All roasted samples had a typical protein spectrum with a maximum absorption at 280 nm and minimum at 260 nm. However, the spectrum of hot air roasted tahina proteins was sharper than the spectra of other tahina proteins. Size exclusion HPLC fractionated tahina proteins into two fractions for hot roasted and vacuum roasted tahinas and three fractions for steam roasted and hot plate roasted tahinas. The gel filtration pattern of tahina proteins contained four peaks with identical elution volumes but different proportions. Hot air roasted and vacuum roasted tahinas had higher panel scores than steam roasted and hot plate roasted tahinas for all tested sensory properties. © 2000 Society of Chemical Industry     

Effects of roasting on phenolics composition and antioxidant activity of peanut (<Emphasis Type="Italic">Arachis hypogaea</Emphasis> L.) kernel flour

The effects of roasting on the phenolics composition and antioxidant activity of peanut (Arachis hypogaea L.) kernel flour were appraised. Peanut kernel flour, with and without skin, were roasted at 160 °C for 10, 20, 30, 40 and 50 min. The resultant changes in the antioxidant activity of roasted peanut kernel flour were assessed by the determinations of total phenolics, 1,1-diphenyl-2-picrylhydrazyl free radical-scavenging capacity, percent inhibition of linoleic acid oxidation and thiobarbituric acid test and compared with those of unroasted kernel flour. It was observed that roasting significantly (p < 0.05) increased the antioxidant activity of the peanut kernel flour. HPLC analysis revealed the detection of three phenolic acids (p-hydroxybenzoic, chlorogenic, p-coumaric), two flavonols (quercetin, kaempferol), and a stilbene (resveratrol) both in the roasted and unroasted samples. In peanut kernel flour without skin, the contents of the phenolics increased in the initial roasting phase, however, decreased gradually in the later phase (>20 min of roasting time). In contrast, over the course of heating, the amounts of phenolics were noted to be slightly increased in the peanut kernel flour with skin; the most significant (p < 0.05) increase occurred in the concentration of p-coumaric acid and quercetin at 30, 40, and 50 min of roasting. The results of this study reveal that optimum roasting time should be sought to enhancing the antioxidant capacity and phenolics concentration in peanut kernel flour.     

Effect of sand roasting on beta glucan extractability, physicochemical and antioxidant properties of oats

The antioxidant properties, damaged starch, beta glucan extractability and physicochemical properties of ten different oat cultivars were studied after sand roasting at 280 °C for 15 s. The groat content within the cultivars varied from 6.59 to 7.76 g/10 g oats. Roasting lowered the length/breadth ratio and bulk density and resulted in puffing of the groats. Color characteristics a∗ indicating redness and b∗ indicating yellowness and nonenzymatic browning index significantly (p < 0.05) increased upon roasting. The total phenolic (μg FAE/g) and flavonoid content (μg/g) decreased significantly by 11.4–50.2% and 22.7–49.9%, respectively. An increase in reducing power (μmol AAE/g) ranging from 1.1 to 37.6% and metal chelating activity ranging from 13.2 to 180.2% was observed in the roasted groats. The DPPH radical scavenging activity in the roasted groats increased by 4.6–73.0%. The peak viscosity of the roasted groat flour decreased by 9.1–51.1% while the final viscosity decreased by 15.4–57.5%. The damaged starch content in the groats increased after roasting and the increase ranged from 72 to 82%. Roasting significantly increased the extractable beta glucan content in the groats by 9.8–61.1%. It was concluded that roasting significantly affects the physicochemical and pasting behavior of groats and increases the availability of phytochemicals like beta glucan and the total antioxidant activity.     

Enzyme deactivation treatments did not decrease the beneficial role of oat food in intestinal microbiota and short‐chain fatty acids: an in vivo study

BACKGROUND: Steaming and roasting treatments are widely used enzyme deactivation methods in the oat food industry in China. Whether or not the enzyme deactivation treatments affect the nutritional function of oat foods is unknown. In the current study, we examined the effects of 4‐week ingestion of steamed or roasted oat foods on the intestinal bacteria and short‐chain fatty acids of rats. RESULTS: Compared with rats taking no oat foods, rats taking normal oat foods or enzyme‐deactivated oat foods showed significantly higher (P < 0.05) counts of Lactobacillus spp. and Bifidobacterium spp. in colon, significantly lower (P < 0.05) counts of Enterococcus spp. and coliforms in colon, and significantly higher (P < 0.05) levels of butyrate and acetate in colonic digesta. In addition, rats taking infrared roasting (IR)‐treated oat foods also demonstrated significantly higher (P < 0.05) fecal Lactobacillus spp. counts and significantly lower (P < 0.05) cecal and fecal counts of E. coli, Enterococcus spp. and coliforms than rats taking no oat foods. As for the comparison between the enzyme‐undeactivated oat group and the three enzyme‐deactivated oat groups, there were no significant differences in most of the parameters (P > 0.05), though a few exceptions did exist. CONCLUSION: Enzyme deactivation treatments did not decrease the beneficial role of oat food in the intestinal microbes and short‐chain fatty acids of rats. © 2012 Society of Chemical Industry     

Performance of dairy cows fed roasted sunflower seed

The objectives of this study were to determine the effects on milk yield, milk composition, ruminal fermentation and total tract nutrient utilization of feeding roasted whole sunflower seed to dairy cows. Three diets were formulated: a control diet with no sunflower seed (NSF), a raw sunflower seed diet (USF) and a roasted sunflower seed diet (RSF). The level of sunflower seed in USF and RSF was 78 g kg^?1 of dry matter (DM). The effects of dietary treatments on yield and composition of milk were determined using nine Holstein cows in three 3 × 3 Latin squares. Three ruminally fistulated cows were used to determine the effects of dietary treatments on ruminal fermentation and total tract nutrient digestibilities. Cows fed sunflower seed diets consumed 8% less (P < 0.05) DM but produced similar amounts of milk as cows fed NSF. However, milk fat content (30.7 vs 33.5 g kg^?1) and yield (1.33 vs 1.47 kg day^?1) were lower (P < 0.05) for cows fed USF and RSF than for those fed NSF. Supplemental sunflower seed had no effect on concentrations and yields of other milk components. The concentrations of short‐chain (C_4:0 to C_12:0) and medium‐chain (C_14:0 to C_16:0) fatty acids were, respectively, 27% and 29% lower (P < 0.05) while those of long‐chain fatty acids (C_18:0 to C_18:3) were 51% higher (P < 0.05) in the milk of cows fed USF and RSF than for cows fed NSF. Ruminal pH, ammonia N and total volatile fatty acids were not affected by dietary treatments. Feeding sunflower seed (USF or RSF) reduced (P < 0.05) the concentration of acetate and increased (P < 0.05) the concentration of propionate. Total tract nutrient digestibilities were not affected by sunflower seed supplementation or by heat treatment. Supplementing dairy cow diets with unheated or roasted sunflower seed improved the efficiency of milk production and increased concentrations of long‐chain and polyunsaturated fatty acids. Feeding sunflower seed at up to 78 g kg^?1 of diet DM had no adverse effects on nutrient utilization. Roasting had no additional benefits on milk yield or milk fatty acid composition. Copyright © 2004 Society of Chemical Industry     

The effect of village processing techniques on the content of aflatoxins in corn and peanuts in Zambia

The effect of village processing techniques on the aflatoxin content of corn and peanut products was investigated. In 30 trials, corn kernels were dehulled (bran removal), soaked for 24 h, washed and dried before grinding into flour and boiling in water to a thick consistency (Nshima). Shelled peanuts were either dry-roasted as whole kernels or ground into peanut meal and cooked. Dehulling, following by 24-h soaking (steeping) and subsequent washing significantly (P<0·05) reduced the aflatoxin B₁ content of corn flour from 900 to 150 μg kg⁻¹, and similarly that of aflatoxin G₁ from 929 to 114 μg kg⁻¹. Preparation of Nshima did not result into a substantial reduction in aflatoxin content, neither did extension of the cooking duration of 2 h afford any further decontamination. Whereas boiling peanut meal yielded a moderate reduction in the content of aflatoxins B₁ and G₁, roasting whole peanut kernels greatly reduced (P<0·001) the concentrations of the toxins from that in raw kernels (AFB₁= 8600 μg kg⁻¹ and AFG₁=6200 μg kg⁻¹) to 1300 and 1200 μg kg⁻¹, respectively. These results indicate that specific processing techniques carried out in Zambian villages are effective in reducing aflatoxin carry-over into edible fractions, while others are not. © 1998 SCI.     

Effect of hot water treatment of in-shell pecans on physicochemical properties and consumer acceptability of roasted pecan kernels

The effect of hot water pre-treatment of in-shell pecans on physicochemical properties, consumer acceptance and purchase intent of dehulled and roasted kernels was evaluated. In-shell pecans were first subjected to hot water at 70, 80 and 90 °C for 8.6, 6.6 and 4.6 min respectively and kernels were later dry roasted at 160 °C for 10 min. The physicochemical properties of hot water treated and untreated nuts, before and after roasting were determined. Furthermore, consumer acceptance and purchase intent of the roasted kernels were determined. Hot water treatment, alone and subsequent roasting had minimal effect on pecans’ physicochemical properties. Consumers liked (P < 0.05) the colour and aroma of treated pecans. No effect (P > 0.05) of pre-treatment was observed on the acceptability of other sensory attributes. Safety claim increased treated pecans’ overall liking; however, it decreased purchase intent. Hot water treatment showed promise as a post-harvest microbial intervention strategy without affecting the physicochemical properties and consumer acceptability.     

Effect of UV-C irradiation on inactivation of Aspergillus flavus and Aspergillus parasiticus and quality parameters of roasted coffee bean (Coffea arabica L.)

ABSTRACT

This study investigated the antifungal effect of ultraviolet-C (UV-C) against Aspergillus flavus and Aspergillus parasiticus on roasted coffee beans. Also, any changes in the quality of the roasted coffee beans were measured after UV-C irradiation. As UV-C irradiation time increased (0–2 h), the number of surviving A. flavus and A. parasiticus spores significantly (P < .05) decreased. The reduction values of A. flavus in round part, crack part, and whole roasted coffee beans were 2.16, 0.71, and 1.58 log₁₀ CFU g^?1, respectively, and the reduction values of A. parasiticus in round part, crack part, and whole roasted coffee beans were 1.03, 0.37, and 0.72 log₁₀ CFU g^?1, respectively, after 2 h of UV-C irradiation. Field emission scanning electron microscopy showed that the morphology of A. flavus and A. parasiticus spores included expanded wrinkles that were deformed by UV-C irradiation. The Hunter colours were significantly reduced (P < .05). There was no significant change (P > .05) in moisture content, but the pH was significantly decreased (P < .05). Most of the sensory parameters did not change, but there was a significant difference (P < .05) in flavour. Based on this study, 2 h of UV-C irradiation was effective in reducing 90% of A. flavus, but it was not effective against A. parasiticus present on roasted coffee beans. Also, Hunter colour, pH, and sensory parameters (flavour) were changed by UV-C irradiation.     

Roasting effects on fatty acid distributions of triacylglycerols and phospholipids in sesame (Sesamum indicum) seeds

Sesame seeds were roasted at different temperatures (180–220 °C) using a domestic electric oven. The positional distribution of fatty acids in triacylglycerols (TAGs) and phosphatidylcholine (PC) isolated from total lipids in these seeds was investigated as well as the naturally occurring antioxidants that are present. Major lipid components were TAGs and phospholipids (PLs), while steryl esters (SEs), free fatty acids (FFAs) and sn‐1,3‐ and sn‐1,2‐diacylglycerols (DAGs) were minor ones. Following roasting, a significant increase (P < 0.05) was observed in FFAs and in both forms of DAG (primarily sn‐1,3‐DAG). The greatest PL losses (P < 0.05) were observed in phosphatidylethanolamine (PE), followed by PC and phosphatidylinositol (PI). On the other hand, the amounts of γ‐tocopherol and sesamin remained at over 80 and 90% respectively of the original levels after roasting at 220 °C. The principal characteristics of the positional distribution of fatty acids were still retained after 25 min of roasting: unsaturated fatty acids, especially linoleic and/or oleic, were predominantly concentrated in the sn‐2‐position, and saturated fatty acids, especially stearic and/or palmitic, primarily occupied the sn‐1‐ or sn‐3‐position. The results suggest that unsaturated fatty acids located in the sn‐2‐position are significantly protected from oxidation during roasting at elevated temperatures. © 2001 Society of Chemical Industry     

Effects of roasting and boiling on the chemical composition,amino acids and oil stability of safflower seeds

The objective of this study was to determine the effects of roasting and boiling on compositional and oil stability of safflower seeds. The moisture, carbohydrate and fibre contents decreased because of roasting and boiling treatments while fat and protein contents increased. The fatty acid compositions of treated samples changed slightly compared with control. The total amount of amino acids in control sample was 151.29, and this amount increased to 158.8 and 186.9 mg g^?1 N by roasting and boiling, respectively. The peroxide value of the oil increased because of roasting and boiling, and it reaches above the accepted value to consumer. Concentrations of major elements such as Na, K and Cu in raw safflower seeds were significantly (P < 0.05) higher than roasted and boiled seeds. The effects of roasting and boiling with regard to loss and retention of the nutrients differed significantly (P > 0.05), with only the roasting retaining more of the nutrients than boiling. The peak intensities of control oil using FTIR spectroscopy were changed in comparison with treated oils.     

Evaluation of the fixed nitrogen-to-protein (N:P) conversion factor (6.25) versus ingredient specific N:P conversion factors in feedstuffs

BACKGROUND: The crude protein (CP) of feedstuffs is important as an indicator of essential and non‐essential amino acids for livestock. The protein (P) level needs to be known accurately, to minimize the feeding of excess nitrogen (N) and to reduce N pollution. Laboratory methods for determining N content report N from amino acids, but also N from ammonia and from non‐amino acid sources. The determined CP based on 6.25 × N level typically overestimates the true protein of feedstuffs. RESULTS: Determined ingredient‐specific N:P conversion factors k_A, k_P and k were not equal to the standard 6.25 factor. The k_A had the highest value in all ingredients, which leads to the estimation of specific crude protein (SCP), which is closer to true protein (the summation of the total amino acid residues from amino acid analyses). The SCP(k_A) was lower than CP and true protein in all ingredients, demonstrating that CP might overestimate the actual protein in feedstuffs. CONCLUSION: Based on data from 677 feedstuff samples from 2009, it is concluded that the mean k_A should be 5.68 for corn, 5.64 for soybean meal, 5.74 for corn DDGS, 5.45 for poultry by‐product meal and 5.37 for meat and bone meal. Copyright © 2011 Society of Chemical Industry     

Effect of Drying and Roasting on the Quality Attributes of Fufu Powder

Abstract

The effect of drying and roasting on the physicochemical and sensory qualities of fufu powder were investigated. The four samples of fufu: cooked dried fufu, cooked roasted fufu, dried fufu slurry and roasted fufu slurry, respectively, were subjected to physicochemical and sensory analysis. The water binding index, water solubility index, and water absorption index, varies between 3.44 and 0.17 (g/g sample), 0.07 and 0.01 (g/g), and 4.73 and 0.83 (g/g) respectively, while the starch damage and amylose content varies between 50.8% and 0.4%, 10% and 13% respectively, with roasted fufu slurries recording the highest values. The proximate composition of dried and roasted fufu samples showed the values of fat (0.6%–0.4%), protein content (0.2%–0.1%), ash content (37.8%–1.0%), moisture content (8.2%–10.2%), crude fibre (1.25%–8.5%) and carbohydrate content (43.0%–84.65%) respectively. Generally, there were no appreciable differences in the proximate composition of dried fufu samples. The pasting temperature of fufu samples varies from 78 to 95°C with roasted fufu slurries recording the highest values. The peak viscosity of dried fufu samples ranges between (80 and 900BU) and viscosity at 50°C ranges between (260 and 460BU). There are no significant differences (P > 0.01) for the sensory qualities in term of color, taste, and overall acceptability except for odor and texture at (P < 0.01).