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Classical methods for assessing the quality of food grains are still in vogue, however, these methods are either destructive or time-consuming which demands an alternative. Spectroscopic techniques...

Adulteration of spices has been a major threat in the past decades as it decreases the quality and causes illness to humans. Testing of species is essential for evaluating the quality and safeguard...

The paper reviews the applications of vibrational spectroscopy for the analysis of teeth. A systematic search of literature published between 1990 and 2018 in the following databases: PubMed/MEDLINE, the Cochrane Library, Academic Search Ultimate, and Google Scholar was completed. Peer reviewed original papers and reviews were searched using the following keywords and phrases in different combinations: teeth/tooth, dental, vibrational spectroscopy, near-infrared spectroscopy (NIR), Raman spectroscopy, Fourier-transform infrared spectroscopy (FTIR), mineralized tissue, hydroxyapatite, geographic, profiling, and characterization. A total of 173 articles matched the inclusion criteria. Of these, 35 studies discussed dental decay; 11 outlined dental maturation and developmental dental defects; 30 assessed demineralization, remineralization, and calcification; 13 analyzed natural and synthetic hydroxyapatite, 50 investigated restorative dentistry and dental medicaments; 22 reported on archeological and anthropological findings, and 12 research studies were conducted in the field of forensics. Despite numerous studies being conducted on the value of vibrational spectroscopy in the characterization of dental tissues, the formulation of geographic profiles through spectroscopic analysis of chemical elements present in teeth has not been attempted hitherto. In particular, information on possible correlations between the chemical dental ‘fingerprints’ of people residing in the same geographic areas has not been investigated.

Meat spoilage is a metabolic process where the change in sensory characteristics deems it to be unacceptable for human consumption. Meat spoilage typically occurs under conditions of optimal water availability, low oxygen, and low temperature conditions, where growth conditions are ideal for microbial growth. Technological advances in the food industry have been at high demand for the past decade, to ensure food safety and health regulations are met using earlier detection methods. Detection technologies such as polymerase chain reactions, spectroscopy, odor sensors devices such as the electric nose are just a few methods used to identify meat spoilage.

Water stress in plants is a complex physiological response to the limited availability of water to a plant. To address the variability in crop water status in different production systems, precision irrigation has been developed and implemented. Reliable measurements or predictions of plant water stress are desirable for numerous agricultural, forestry, conservation, and land rehabilitation applications. However, in order to implement precision irrigation, this method requires accurate information about the crop water status, soil moisture content, and weather (e.g., wind speed and vapor pressure deficit). Various technologies, including remote- and ground-based sensors, were developed, and some of them are available for the measurement of plant water stress. The objective of this article is to review the use of near-infrared (NIR) sensors to measure water potential in different crops and plants.

Wine production is directly linked with the monitoring of the fermentation and critical fermentation parameters such as total sugars and ethanol concentration, and the production of CO2. Commonly used sensors applied in the wine industry to monitor wine fermentation are those based in single sensors such as temperature probes and manual density measurements (e.g., specific gravity). These sensors are used several times per day and have been the only source of data available from which the stage of the fermentation and the evolution rate could be monitored. Therefore, an ideal method for fermentation process control and monitoring should enable a direct rapid, precise, and accurate determination of several target compounds, with minimal or no sample preparation and reagent consumption. This article reviews the state of the art in the applications of both near and mid infrared spectroscopy to monitor beer and wine fermentation.

Soil is critical to the world, supplying virtually all of the food and fiber that sustain the human population and providing the space for the ecosystems that support life. The characterization of soil properties through laboratory analysis is an essential part of the diagnosis of the potential use of lands and their fertility. However, conventional soil chemical analyses are expensive and time consuming, hampering the adoption of soil management practices. In recent years, farmers are also increasingly demanding rapid, cost-effective, and nondestructive methods for monitoring changes as well as measuring the physical-chemical properties in soils. This article reviews applications of near infrared (NIR) spectroscopy to assess, monitor, and classify soils in South America.

The aim of the experiment was to study diurnal variation in water-soluble carbohydrate (WSC) concentrations in leaf and stem of tall fescue and lucerne in autumn and to determine the impact of these changes on the rate and the extent of in vitro fermentation. Vegetative herbage of lucerne and tall fescue were sampled at 0900, 1300 and 1700 h, following three consecutive regrowths between April and May. Whole plants, leaf and stem were analysed for chemical composition and in vitro gas production. There was a linear increase in WSC throughout the day for all plants and plant components (P < 0.001). In both fescue and lucerne, this rise resulted in an increased rate of gas production, although this relationship was more pronounced in fescue. Use of time of day to govern grazing management decisions to potentially improve the rumen supply of WSC and nitrogen in autumn can be achieved from tall fescue or lucerne pastures.

As a fast and easy-to-operate technique, infrared (IR) spectroscopy has gained wide industrial acceptance for routine wine analysis. Considering the continuing improvements in hardware and software design and the analytical requirements of real-time or multiparametric analysis by the modern grape and wine industry, it is anticipated that in the near future IR spectroscopy will progressively become a routine method for process monitoring and process control in different stages of grape and wine production. This review highlights recent developments and applications of IR spectroscopy (near- and mid-infrared) to measure compositional parameters in wine grapes, grape juice, and grapevine tissues (e.g., leaves, stems, grapevine wood). In addition, some critical aspects and limitations in instrument availability, type of application, and overall understanding of the technology, which can be barriers for adoption of IR technologies by the grape and wine industry, will be discussed.

Recent developments in agricultural technology have led to a demand for a new era of nondestructive methods of plant analysis in the field rather than in the laboratory. The combination of fundamental science (e.g., plant physiology, biochemistry, and other disciplines), multivariate data analysis, and spectroscopy will enable the development of technologies for reliable and rapid on-farm or in-field low-cost testing. This will enable both farmers and scientist to maximize sales in existing markets and to target new markets with differentiated products or select new varieties, better soil management, among other issues. Infrared (IR) spectroscopy has been successfully applied for the determination of composition analysis in several fields (e.g., agriculture, pharmaceutical, etc.) and in product quality assessment and production control. The IR spectrum can give a global signature of composition (fingerprint), which, with the application of chemometric techniques, can be used to elucidate particu...

This study reports the use of near-infrared (NIR) reflectance spectroscopy combined with two-dimensional correlation (2D-COS) spectroscopy to monitor the effect of soaking and water uptake by the barley endosperm (Hordeum vulgare, L). The synchronous 2D-COS maps derived from the NIR spectra of barley endosperm showed similarities that could be explained by the regions in the spectra associated with water as well as with the biochemical and biophysical changes as a consequence of the water uptake by the grain. The results also demonstrated the potential of 2D-COS combined with NIR spectroscopy as an analytical tool to study changes in the biophysical characteristics of whole barley during steeping or soaking. This method can be used to obtain information about the effect of water uptake in other chemical characteristics of the endosperm of cereal grains.

This study evaluated an in-field near-infrared (NIR) instrument to predict the contents of total nitrogen (TN), organic carbon (OC), potassium (K), sulfur (S), phosphorus (P), pH, and electric conductivity (EC) in soil vineyard samples (n = 70) sourced from three wine regions of Australia. Samples were analyzed using a portable NIR spectrophotometer (ASD FieldSpec III, 350-1800 nm). Partial least squares (PLS) regressions yield a coefficient of determination in calibration (R2) and a standard error in cross validation (SECV) of 0.74 (0.03) for TN, 0.92 (2.19) for S, 0.81 (0.42) for OC, 0.70 (109.2) for K, 0.84 (0.03) for EC, 0.83 (0.44) for pH, and 0.69 (24.6) for P, respectively. This study showed that it is possible to measure soil chemical properties in the vineyard, and the main advantages of this approach will be the speed, low cost, and ability to better manage and monitor soil fertility.

Large residual stresses are an undesirable but inevitable side effect of fusion welding operations, and localised high pressure rolling of the weld seam is a proposed method for eliminating them. In this study, neutron diffraction has been used to map the residual stresses within low carbon steel weld seams treated with high pressure rolling. The effect on the residual stress distribution of using different roller types was determined, along with the influence of these different rollers on final weld seam geometry. Rolling was found to completely change the residual stress state in the weld, creating large compressive longitudinal residual stresses. It was effective for this purpose regardless of whether it was applied directly to the weld seam or to regions either side of it. The fatigue life of welded specimens was shown to be reduced by rolling; however, it is suggested that this is due to geometric and metallurgical effects.

One technique for reducing residual stress in welds is high pressure rolling of the weld seam. In this study, a variety of experimental techniques, including microhardness measurements and cross-weld tensile tests with digital image correlation, have been used to characterise the effects of rolling on the mechanical properties and microstructure of the weld material in welded structural steel specimens. It is shown that rolling applied at high temperature, as welding is carried out, promotes the formation of acicular ferrite in the weld metal. This produces a weld material with a greater yield strength and hardness, but slightly reduced impact toughness compared to unrolled welds. Rolling of the weld metal once it has cooled instead causes work-hardening. These effects are discussed as they relate to the use of rolling for weld residual stress reduction.

Verification of the authenticity of natural and agricultural foods has become a potential application of spectroscopic methods such as ultraviolet (UV), visible (VIS), near infrared (NIR), and mid-infrared (MIR). Adulteration can take many forms, including the addition of sugars, acids, volatile oils, overdilution of concentrate, addition of juices of other fruits, use of concentrate in a fresh product, and use of low-quality product recovered from what are normally waste products of manufacture. Food adulteration has been practiced since ancient times but has become more sophisticated in the recent past. Foods or ingredients most likely to be targets for adulteration include those that are of high value or subject to the vagaries of weather during their growth or harvest. The practice of adulteration commonly arises for two main reasons: firstly, it can be profitable, and secondly, adulterants can be easily mixed and are subsequently difficult to detect. To counter this problem, manufacturers subject their raw material and by-products to a series of quality controls, including high-performance liquid chromatography (HPLC), thin-layer chromatography (TLC), enzymatic tests, and physical tests. This mini-review highlights recent applications on the use of NIR and MIR spectroscopy to trace and authenticate natural and agricultural products.

The formation of large residual stresses continues to be a problematic side effect of all common welding processes. In this work, localised high pressure rolling of gas metal arc welds to relieve these residual stresses has been investigated using strain gauging and neutron diffraction. Rolling was found to remove undesirable tensile stresses and even induce large compressive ones, though only when applied after rather than during welding. Strain measurements taken during combined welding and rolling operations show that this is because material at the weld line continues to yield as it cools. This erases any beneficial effect on the stress distribution of rolling at high temperature. A method of rolling using an oscillating force is also presented and found to be just as effective as the equivalent static force process.

Demand for high levels of quality and safety in fish production obviously require high standards in quality assurance of raw materials and process control. Satisfying this demand in turn requires appropriate analytical tools for analysis both during and after production. Desirable features of such tools include speed, ease of use, minimal or no sample preparation, and the avoidance of sample destruction. These features are characteristic of a range of spectroscopic methods including mid-infrared (MIR) and near-infrared (NIR) spectroscopy. This article reviews some of the recent technical applications of infrared (IR) spectroscopy to determine and monitor composition and other quality characteristics in raw fish, fish products, and seafood.

Honey is a carbohydrate-rich syrup and viscous fluid produced by honeybees (Apis mellifera) from the nectar of flowers that, by definition, does not include any other substances. Honey is produced primarily from floral nectars, and fructose and glucose are the major components. Overall, the chemical composition of honey varies depending on plant source, season, production methods, and storage conditions. Analytical methods applied to honey generally deal with different topics such as determination of botanical or geographical origin, quality control according to the current standards, and detection of adulteration or residues. Traditional chemical composition analysis and physical properties assessment are routinely performed in commercial trading of honey using time-consuming analytical methods that require considerable sample preparation and analytical skills. Spectroscopic techniques in the infrared (IR) wavelength region of the electromagnetic spectrum have been used in the food industry to monitor and evaluate the composition of foods and are becoming one of the most attractive and commonly used methods of analysis. This review discusses the use, with advantages and limitations, of IR spectroscopy technologies to evaluate and monitor the composition of honey.

Commercial meat pate samples, comprised of 100% pork (n = 7), 100% beef (n = 5) meat, and binary mixtures (beef and pork, w/w) (n = 18) were used. Fresh samples were analysed in a scanning spectrophotometer NIRSystems 6500 in reflectance mode (1100-2500 nm). Principal component analysis (PCA) and stepwise linear discriminant analysis (SLDA) were used to classify samples according to the animal species based on their near infrared reflectance (NIR) spectra. Full cross validation was used as validation method when classification models were developed. Both beef and pork pate samples were classified correctly (100%) while binary mixture samples only achieved 72% of correct classification using SLDA technique. The results demonstrated the usefulness of NIR spectra combined with chemometrics as an objective and rapid method to classify pate samples according to meat type. Nevertheless, NIR spectroscopic methods might provide initial screening in the food chain and enable more costly methods to be used more efficiently.

This study evaluates the effect of soil particle size (SPS) on the measurement of exchangeable sodium (Na) (EXC-Na) by near-infrared reflectance (NIR) spectroscopy. Three hundred thirty-two (n = 332) top soil samples (0–10 cm) were taken from different locations across Uruguay, analyzed by EXC-Na using emission spectrometry, and scanned in reflectance using a NIR spectrophotometer (1100–2500 nm). Partial least squares (PLS) and principal component regression (PCR) models between reference chemical data and NIR data were developed using cross validation (leaving one out). The coefficient of determination in calibration (R2) and the root mean square of the standard error of cross validation (RMSECV) for EXC-Na concentration were 0.44 (RMSECV: 0.12 mg kg–1) for soil with small particle size (SPS-0.053) and 0.77 (RMSECV: 0.09 mg kg–1) for soils with particle sizes greater than 0.212 mm (SPS-0.212), using the NIR region after second derivative as mathematical transformation. The R2 and RMSECV for EXC-Na concen...

The use of ultraviolet (UV), visible (VIS), near infrared reflectance (NIR), and midinfrared (MIR) spectroscopy techniques have been found to be successful in determining the concentration of several chemical properties in soils. The aim of this study was to evaluate the effect of two reference methods, namely Bray and Resins, on the VIS and NIR calibrations to predict phosphorus in soil samples. Two hundred (n=200) soil samples were taken in different years from different locations across Uruguay with different physical and chemical characteristics due to different soil types and management. Soil samples were analyzed by two reference methods (Bray and Resins) and scanned using an NIR spectrophotometer (NIRSystems 6500). Partial least square (PLS) calibration models between reference data and NIR data were developed using cross‐validation. The coefficient of determination in calibration (R2) and the root mean square of the cross validation (RMSECV) were 0.58 (RMSECV: 3.78 mg kg−1) and 0.61 (RMSE...

SUMMARYNear infrared reflectance spectroscopy (NIRS) was used to assess the chemical composition of fresh honey samples. Samples (n = 110) from different locations across Uruguay were scanned in transreflectance (0.2 mm path—length) in a NIRS 6500 monochromator in both the visible and near infrared region (400–2500 nm). Prediction equations were developed using modified partial least squares and cross validation was applied to avoid overfitting. Calibrations for water content (g kg−1), pH, electrical conductivity (mS/cm), colour (mm Pfund) and hydroxymethylfurfural (mg kg−1) yielded a coefficient of determination in calibration (R2CAL) and standard error in cross validation of 0.96 (SECV: 31); 0.88 (SECV: 0.21); 0.94 (SECV: 0.07); 0.98 (SECV: 4.7) and 0.67 (SECV: 3.9), respectively. It is concluded that NIRS is a useful method to evaluate chemical composition on fresh honey samples.

D Cozzolino1, W U Cynkar1, N Shah1, R G Dambergs2, P A Smith11The Australian Wine Research Institute, Urrbrae, Glen Osmond, SA, Australia; 2The Australian Wine Research Institute, Tasmanian Institute of Agricultural Research, University of Tasmania, Hobart, Tasmania, AustraliaAbstract: Real-world systems are usually multivariate and hence usually cannot be adequately described by one selected variable without the risk of serious misrepresentation. Analyzing the effect of one variable at a time by analysis of variance techniques can give useful descriptive information, but this will not give specific information about relationships among variables and other important relationships in the entire matrix. Multivariate data analysis was developed in the late 1960s, and used by a number of research groups in analytical and physical organic chemistry due to the introduction of instrumentation giving multivariate responses for each sample analyzed. Development of such methods was also made possible by the availability of computers. Multivariate data analysis involves the use of mathematical and statistical techniques to extract information from complex data sets. The objective of this paper is to briefly describe and illustrate some multivariate data analysis methods used for grape and wine analysis.Keywords: multivariate analysis, data mining, wine, grape&nbsp