Determination of fat in live farmed Atlantic salmon using non‐invasive NIR techniques

Non‐destructive near‐infrared (NIR) measurements were performed on 100 live, anaesthetised farmed Atlantic salmon, whole weight 1–11 kg, using two different NIR instruments: a grating monochromator instrument equipped with a fibre optic interactance probe, and a diode array instrument measuring diffuse reflectance in a non‐contact mode. Crude fat content was determined using partial least squares (PLS) regression. Full cross‐validation was used to evaluate the performance of the calibration models, expressed as the root mean square error of prediction (RMSEP). For the fibre optic instrument the wavelength range from 800 to 1098 nm resulted in a correlation coefficient of 0.90 and an RMSEP equal to 14 g kg^?1 fat. The diode array instrument using the wavelength range from 900 to 1700 nm gave results of the same accuracy. The measurement times were 21 and 3 s respectively. It is concluded that either instrument could be used to determine the crude fat content in live Atlantic salmon, with good accuracy. © 2003 Society of Chemical Industry     

Mapping of Fat and Moisture Distribution in Atlantic Salmon Using Near-Infrared Hyperspectral Imaging

A nondestructive and rapid method using near-infrared (NIR) hyperspectral imaging was investigated to determine the spatial distribution of fat and moisture in Atlantic salmon fillets. Altogether, 100 samples were studied, cutting out from different parts of five whole fillets. For each sample, the hyperspectral image was collected with a pushbroom NIR (899–1,694 nm) hyperspectral imaging system followed by chemical analysis to measure its reference fat and moisture contents. Mean spectrum were extracted from the region of interest inside each hyperspectral image. The quantitative relationships between spectral data and the reference chemical values were successfully developed based on partial least squares (PLS) regression with correlation coefficient of prediction of 0.93 and 0.94, and root mean square error of prediction of 1.24 and 1.06 for fat and moisture, respectively. Then the PLS models were applied pixel-wise to the hyperspectral images of the prediction samples to produce chemical images for visualizing fat and moisture distribution. The results were promising and demonstrated the potential of this technique to predict constituent distribution in salmon fillets.     

Atlantic Salmon Average Fat Content Estimated by Near-Infrared Transmittance Spectroscopy

Near-infrared transmittance spectroscopy was used to determine the average fat content in farmed Atlantic salmon fillets with skin and scales. The fat content was 5.7–17.6% and weight range 1.0–5.4 kg. A partial least square regression including 43 salmon resulted in a multivariate prediction correlation of 0.97 and a root mean square error of cross validation of 0.75%. Regression models using 6 to 9 wavelengths in the 850–1048 nm range gave somewhat lower prediction errors than a model using 100 wavelengths. Results showed that NIR transmittance was suited to determine fat content nondestructively in whole salmon fillets with skin and scales.     

Composition,variation of nutritional contents in leaves,seed protein,fat and fatty acid profile ofchenopodium species

The foliage of Chenopodium belonging to 10 species were analysed for selected nutritional and antinutritional components. The overall range of moisture was 757-910 g kg^?1, carotenoid 78-190 mg kg^?1, vitamin C 0.5-2.4 g kg^?1, protein 26-64 g kg^?1, nitrate 2.6-5.0 g kg^?1 and oxalate 9-39 g kg^?1 (fresh wt). Variation of all the six parameters with respect to leaf position from the apex showed the highest amount of carotenoid at 7-8, vitamin C at 9-10, protein at 5-6 and nitrate in the youngest leaves, followed by a continuous decrease with age (increasing position). However, oxalate contents always tended to increase with leaf position (age). The protein, fat and fatty acid composition in seeds of eight species were also analysed. Protein varied from 106 to 142 g kg^?1 and fat from 30 to 62 g kg^?1; palmitic, oleic and linoleic were the major fatty acids in the oils.     

Non-invasive and non-destructive percutaneous analysis of farmed salmon flesh by near infra-red spectroscopy

Near infra-red (NIR) reflectance spectroscopy (700–1100 nm wavelength range) has been applied to the percutaneous measurement of oil and moisture in farmed salmon carcasses. Spectra were recorded through the skin and scales by means of a fibre-optic probe. Six selected sites were used on the dorsal and ventral surfaces of each fish side; 294 sample sites were utilized. Reference chemical values for oil and moisture were determined on these sites after excision. Calibrations were developed and evaluated separately for dorsal and ventral sites. The best dorsal calibration produced a standard error of prediction (SEP) for oil and moisture of 2.0 and 1.45%, respectively; corresponding figures for the best ventral calibration were 2.4 and 1.9%, respectively.     

Non‐destructive texture analysis of farmed Atlantic salmon using visual/near‐infrared reflectance spectroscopy

Fillets of farmed Atlantic salmon were assessed by visual/near‐infrared (VIS/NIR) reflectance spectroscopy, Kramer shear force measurement and texture profile analysis (TPA). Comparison of the Kramer measurements between pairs of subsamples gave correlation coefficients of 0.85 for pre‐rigor (2 h after slaughter), 0.78 for post‐rigor (6 days after slaughter) and 0.97 for pre‐ and post‐rigor combined. TPA gave non‐significant correlations between subsamples. VIS/NIR fibre optic probe measurements gave cross‐validated correlation coefficients for prediction of Kramer shear force of 0.76 for pre‐rigor, 0.68 for post‐rigor and 0.94 for pre‐ and post‐rigor combined. Classification using linear discriminant analysis of the VIS/NIR measurements gave up to 79% correct classification into three categories: low Kramer shear force (2.13 × 10^?2–4.41 × 10^?2 J g^?1), medium Kramer shear force (4.41 × 10^?2–6.37 × 10^?2 J g^?1) and high Kramer shear force (6.37 × 10^?2–7.90 × 10^?2 J g^?1). Using these class limits, no low‐Kramer‐shear‐force sample was misclassified as a high‐Kramer‐shear‐force sample, and vice versa. It can be concluded that non‐destructive VIS/NIR fibre optic probe measurement gives fair predictions of Kramer shear force. Its most useful application in salmon production plants may be to classify fillets into broad classes according to texture before further processing or sale. © 2001 Society of Chemical Industry     

Nutritional and antinutritional composition of vegetable and grain amaranth leaves

The foliage of 61 accessionso f amaranthus comparising both the grain and vegetable types referable to 10 species were evaluated for carotenoid, protein, nitrate, odxalate and moisture contents (fresh weight). Carotenoid varied from 90 to 200 mg kg^?1 in vegetable types and from 60 to 200 mg kg^?1 in the leaves of grain types. Variation for leaf protein was found to be 14-30, 15-43 g kg^?1; nitrate 1.8.-8.8, 4.1-9.2 g kg^?1; oxalate 5.1-19.2, 3-16.5 g kg^?1; and moisture 780-860, 750-840 g kg^?1 in vegetable and grain types, respectively. Analysis of the amino acid composition of leaf protein of some high carotenoid lines revealed a well balanced composition with high lysine (40-56 g kg^?1). variation of all the five parameters (carotenoid, protein, nitrate, oxalate and moisture) with respect tot he leaf position in vegetable type (4- and 8-week-old plants) and with respect to age (- to 4-month-old plants) in grain types was also studied.     

Non-Destructive Determination of Fat and Moisture in Whole Atlantic Salmon by Near-Infrared Diffuse Spectroscopy

A near-infrared spectrometer equipped with an interactance optical fiber probe was used to determine the average crude fat and moisture content in the muscle of whole Atlantic salmon (Salmo salar). The fat contents were 8.8—19.2% and moisture 61.0—70.8%, and fish weight range 1.0—5.7 kg. A partial least square regression including 49 salmon resulted in root mean square error of cross validation of 1.12% fat (R = 0.87) and 0.98% moisture (R = 0.86). Results showed that NIR interactance was a suitable non-destructive screening method for fat and moisture content in farmed Atlantic salmon.     

Prediction of fat in intact cereal food products using near‐infrared reflectance spectroscopy

To evaluate the feasibility of an intact product approach to the near‐infrared (NIR) determination of fat content, a rapid acquisition spectrometer, with an InGaAs diode‐array detector and custom built sampling device, was used to obtain reflectance spectra (1100–1700 nm) of diverse cereal food products. Fat content reference data were obtained gravimetrically by extraction with petroleum ether (AOAC Method 945.16). Using spectral and reference data, partial least‐squares regression analysis was applied to calculate a NIR model (n = 89) to predict fat in intact cereal products; the model was adequate for rapid screening of samples, predicting the test samples (n = 44) with root mean square error of prediction (RMSEP) of 11.8 (range 1.4–204.8) g kg^?1 and multiple coefficient of determination of 0.98. Repeated repacking and rescanning of the samples did not appreciably improve model performance. The model was expanded to include samples with a broad range of particle sizes and moisture contents without reduction in prediction accuracy for the untreated samples. The regression coefficients for the models calculated indicated that spectral features at 1165, 1215 and 1395 nm, associated with CH stretching in fats, were the most critical for model development. Published in 2005 for SCI by John Wiley & Sons, Ltd.     

Development of lipid oxidation during manufacturing of horse mackerel surimi

When fatty fish are transformed into surimi, lipid oxidation takes place, decreasing the quality of the product. This study was aimed to identify the critical stages of the process in terms of the development of lipid oxidation. Horse mackerels were transformed into surimi on a pilot line and samples taken (hand‐skinned fillets = minced fillets, mince, washed and refined minces, paste, surimi and washing water). Most of the lipids were removed during the process and neutral lipids were lost in higher proportion than polar lipids. As a consequence, total lipids of surimi contained more polyunsaturated fatty acids (338 ± 19 g kg^?1) than total lipids of the minced fillets (220 ± 8 g kg^?1). Thiobarbituric acid reactive substances (TBARS) was higher in the minced fillets than in the mince because less subcutaneous fat and dark muscle were removed during hand‐mincing, indicating that the settings of the skinning–deboning machine can strongly influence the final quality of the product. Concentrations of lipid oxidation products increased significantly during the next stages of surimi processing. The increase was more pronounced for TBARS than hydroperoxides. Concentrations in hydroperoxides were similar in mince and washed mince (15.3 ± 2.8 and 16.6 ± 2.8 mmoles kg^?1 lipid) and increased in refined mince (29.6 ± 2.8 mmoles kg^?1 lipid). TBARS accounted for 2.7 ± 1.0 mg kg^?1 lipid in mince, 40.4 ± 2.3 mg kg^?1 lipid in washed mince and 237 ± 7 mg kg^?1 lipid in refined mince. Hydroperoxides and TBARS were found in appreciable amounts in washing water (76.9 ± 4.7 mmoles kg^?1 lipid and 479 ± 8 mg kg^?1 lipid respectively), when they decreased in surimi (27.3 ± 3.8 mmoles kg^?1 lipid and 44.2 ± 0.8 mg kg^?1 lipid respectively) compared with refined mince. This shows that the last dewatering stage is crucial to ensure surimi quality. Copyright © 2005 Society of Chemical Industry     

Multivariate determination of free fatty acids and moisture in fish oils by partial least-squares regression and near-infrared spectroscopy

The oxidative and hydrolytic degradation of lipids in fish oil was monitored using partial least-squares (PLS) regression and near-infrared reflectance (NIR) spectroscopy. One hundred and sixty (n=160) fish oil samples from a fishmeal factory were scanned in transflectance by an NIR monochromator instrument (1100–2500 nm). Calibration models were performed for free fatty acids (FFA), moisture (M), peroxide value (PV) and anisidine value (AV). Coefficients of determination in calibration (R²) and standard errors of cross validation (SECV) were 0.96 (SECV: 0.59) and 0.94 (SECV: 0.03) for FFA and M in g/kg, respectively. The accuracy of the NIR calibration models were tested using a validation set, yielding coefficients of correlation (r) and standard errors of prediction (SEP) of 0.98 (SEP: 0.50) and 0.80 (SEP: 0.05) for FFA and M in g/kg, respectively. Poor accuracy (R²<0.80) was obtained for the NIR calibration models developed for PV and AV. The paper demonstrates that fish oil hydrolytic degradation of lipids, which seriously affect oil use and storage under industrial conditions, can be successfully monitored using PLS regression and NIR spectroscopy by the fishmeal industry.     

The potential of NIR spectroscopy for the detection of the adulteration of orange juice

Near-infrared spectroscopy was used to investigate the adulteration of 65 authentic concentrated orange juice samples obtained from Brazil and Israel. These samples were adulterated with 100 g kg^?1 additions (ie 100 g added to 900 g) of (1) orange pulpwash, (2) grapefruit juice, and (3) a synthetic sugar/acid mixture and with 50 g kg^?1 additions (ie 50 g added to 950 g) of (4) orange pulpwash, and (5) grapefruit juice. All samples were scanned on the NIR systems 6500 spectrophotometer over the 1100-2498 nm wavelength range. Principal component analysis was used to reduce each spectrum to 20 principal components. Factorial discriminant analysis was used to distinguish between the different sample groups. Using orange juice and orange juice adulterated at the 100 g kg^?1 level, accurate classification rates of 94–95% were obtained. To classify samples adulterated at the 50 g kg^?1 level, the calibration development sample set had to be augmented by the inclusion of samples adulterated at this lower level—after this augmentation, an accurate classification rate of 94% was obtained. The results demonstrated that the application of principal component and factorial discriminate analysis to NIR reflectance spectra can detect the adulteration of orange juice with an average accuracy of 90%. Furthermore, not one adulterated sample was predicted as being an authentic orange juice throughout the entire test regime.     

The proximate composition and some minor constituents of poppy seeds

The proximate chemical composition of poppy seeds, along with minerals and water-soluble vitamins content was investigated. The compositions of the fatty acids and tocopherols of the extracted oil were also determined. The proximate analysis of poppy seeds showed the following composition: (440 g kg^?1), protein (211 g kg^?1), moisture (50 g kg^?1), ash (63 g kg^?1), crude fine (62 g kg^?1) and total carbohydrates (236 g kg^?1). Potassium and calcium were the predominant elements in the poppy seeds. Linoleic acid was the major unsaturated fatty acid (750 g kg^?1 total fatty acids) while palmitic acid was the main saturated one (86-4 g kg^?1). The amounts of α-, β- and δ-tocopherols found in poppy seed oil were 220 μg g^?1, 40 μg g^?1 and 20 μg g^?1 respectively. Among the water-soluble vitamins determined, pantothenic acid was found at the highest level followed by niacin and thiamin.     

Growth,nutritional quality and safety of oysters (Crassostrea gigas) cultured in the lagoon of Venice (Italy)

Quality aspects of oysters (Crassostrea gigas) from a suspended culture in the lagoon of Venice (Valle Dogà) were examined in different seasons over a 1‐year period. Ecophysiological and commercial quality indicators (condition index, content of meat, shell and intervalvar fluid), nutritional quality parameters (proximate and mineral composition, glycogen content, fatty acid profile, cholesterol, plant sterols, fat‐soluble vitamins content) and levels of organic pollutants (polychlorinated biphenyls and organochlorine pesticides) were determined at different times of the year. Seasonal variations were observed in the nutrient content, with particular regard to moisture (ranging from 866.8 g kg^?1 in June to 938.8 g kg^?1 in September), protein (23.9 g kg^?1 in September to 76.6 g kg^?1 in June), ash (22.5 g kg^?1 in February to 29.5 g kg^?1 in July), lipid (3.0 g kg^?1 in September to 8.8 g kg^?1 in June) and glycogen (0.7 g kg^?1 in September to 11.5 g kg^?1 in February). In spite of this variability, the nutritional quality of the oysters was generally good, especially just before gamete release when the concentration of nutrients was at its maximum. Low levels of organochlorine chemicals were detected in the edible meat of oysters but, because only a limited number of samples were analysed, no general conclusion can be drawn on the safety of seafood from this area. Copyright © 2004 Society of Chemical Industry     

Preparation and composition of chhana whey powders using membrane processing techniques

Chhana is a traditional Indian product used widely in the confectionery industry. It is produced from cow's milk by a combination of heat and acid coagulation. Chhana whey contains about 6% milk solids yet the vast majority is wasted which leads to pollution problems. This study describes the chemical composition and various options for utilisation of chhana whey using membrane processes. Chhana whey powder containing 956 g kg^?1 total solids, 750 g kg^?1 lactose, 21 g kg^?1 protein. 60 g kg^?1 fat, 65 g kg^?1 ash was produced following concentration of chhana whey by reverse osmosis. Chhana whey protein concentrate powders containing 270, 350, 400 and 580 g kg^?1 protein were produced following ultrafiltration or diafiltration of chhana whey.     

Toxicokinetics and carry-over model of α-hexabromocyclododecane (HBCD) from feed to consumption-sized Atlantic salmon (Salmo salar)

A two-compartmental model for the kinetics of carry-over of the brominated flame retardant α-hexabromocyclododecane (HBCD) from feed to the fillet of farmed harvest-sized Atlantic salmon (Salmo salar L.) was developed. The model is based on a fat compartment for storage of the lipophilic α-HBCD and a central compartment comprising all other tissues. Specific for this model is that the salmon has a continuous growth and that fillet contaminant levels are explained by both the fat and the central compartments. The uptake and elimination kinetics are obtained from experimental data where consumer sized (start weight approximately 1?kg) Atlantic salmon was fed α-HBCD spiked feed (280?±?11?µg?kg^?1) for 2 months followed by a depuration period of 3 months. The model was used to simulate the HBCD feed-to-fillet transfer in Atlantic salmon under realistic farming conditions such as the seasonal fluctuations in feed intake, growth and fillet fat deposition. The model predictions gave fillet concentrations of 0.2–1.8?µg?kg^?1 depending on the level of fish oil inclusion in the salmon diets when using fish oil with high POP background levels. Model simulations show that currently farmed Atlantic salmon can contribute to a maximum of 6% of the estimated provisional food reference dose for HBCD.     

Fat reduction in emulsion sausage using an enzyme‐modified potato starch

BACKGROUND: A heat‐stable amylase‐modified potato starch (MPS) was prepared and used as a fat replacer in reduced‐fat emulsion sausages. The effects of fat level (50, 150 and 300 g kg^?1) and MPS addition (20 and 40 g kg^?1) on energy, colour, sensory, and textural properties of emulsion sausages were investigated. RESULTS: The addition of 20 or 40 g kg^?1 of MPS in reduced‐fat sausage (50–150 g kg^?1 fat) reduced total energy (15.1–49.4%), increased lightness, but lowered redness of the products (P < 0.05). The 150 g kg^?1 or 50 g kg^?1 fat sausages containing 20 g kg^?1 MPS had a similar hardness to the 300 g kg^?1 fat control (P > 0.05). Sensory evaluation indicated that the presence of MPS in reduced‐fat sausages increased (P < 0.05) the product's tenderness. CONCLUSION: Overall, the 150 g kg^?1 fat emulsion sausages with 20 g kg^?1 MPS were comparable to the 300 g kg^?1 fat control sausage in colour, texture profile, and sensory properties, but was lower in energy, suggesting that the MPS can be used as a potential fat replacer in sausage products. Copyright © 2008 Society of Chemical Industry     

Modelling the long-term feed-to-fillet transfer of leuco crystal violet and leuco malachite green in Atlantic salmon (Salmo salar)

Leuco crystal violet (LCV) and leuco malachite green (LMG) are the main metabolites of two dyes that are forbidden for use in food production, but can be present at low background concentration in novel Atlantic salmon feed ingredients such as processed animal proteins (animal by-product [ABP]). In this study, the potential transfer of dietary LCV or LMG to the fillet of farmed Atlantic salmon was investigated. The uptake and elimination rate kinetics were determined in seawater-adapted Atlantic salmon (initial weight 587 ± 148 g) fed two levels of either LCV- or LMG-enriched diets (~500 and 4000 µg kg^?1, respectively) for 40 days, followed by a 90-day depuration period with feeding on control diets (<0.15 μg kg^?1 LCV and LMG). A three-compartmental model was developed, based on a fillet fat, fillet muscle and a central body compartment comprising all other tissues. Model calibrations showed a good fit with measured values during overall uptake and elimination period; however, the model poorly predicted the short-term (days) peak measured values at the end of the exposure period. The model was used to simulate the long-term (>16 months) LCV and LMG feed-to-fillet transfer in Atlantic salmon under realistic farming conditions such as the seasonal fluctuations in feed intake, growth and fillet fat deposition. The model predictions gave highest expected LCV and LMG fillet concentrations of approximately 0.12 and 0.45 μg kg^?1, depending on the dietary levels of ABP and background level of LCV and LMG contamination. These levels are under the reference point for action of 2 µg kg^?1 for the sum of MG and LMG that EFSA assessed as adequate to protect public health. However, for LCV, the predicted highest levels exceed the analytical decision limit (CCα) of 0.15 µg kg^?1 for the method used in this paper.     

Protein,fat and fatty acid composition of Celosia species

The seeds of 13 lines of Celosia referable to four species were analysed for protein, fat and fatty acid composition. The protein contents varied from 101 to 170 g kg^?1 and fat contents from 56 to 109 g kg^?1. The fatty acid composition was of the simple palmitic-oleic-linoleic type.     

Proximate analysis of homogenized and minced mass of pork sausages by NIRS

Near infrared spectroscopy was employed to analyse samples of pork sausage meat used in the manufacturing of typical Spanish sausages (minced and homogenized product). As well, two modes of analysis for the instrument were compared. Data from proximate analysis (fat, moisture and protein) were put into a calibration model by a diode array NIR spectrometer. The spectral range used was 515–1650 nm and different mathematical pre-treatments on the signal (derivatives and scatter corrections) were also compared. Different mathematical pre-treatments caused considerable changes in the statistics of the models (coefficients of determination and standard errors). R² (calibration) and standard errors of prediction (SEP, external validation) in minced sausage meat for fat, moisture and protein were 0.98, 0.98 and 0.93 (R²) and 1.38%, 1%, 0.83% (SEP), respectively. These values in homogenised sausage meat for fat, moisture and protein were 0.99, 0.98 and 0.93 (R²), and 0.94%, 0.76% and 0.87% (SEP), respectively.