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During the last 30 years, food scientists and technologists all over the world are dealing with massive amounts of data derived from the use of different measuring devices (e.g. instrumental and sensory data), the integration of different analytical techniques and processes during the analysis and production of foods. Therefore, complementary disciplines and tools to the traditional ones used in food science such as statistics, experimental design and chemometrics have become essential in modern sciences and are an integral component in the day-to-day analysis of foods and derived products. The aim of this paper is to introduce as well as provide with an overview of different concepts, methods, techniques and general steps used in the quantitative analysis of foods when chemometrics or multivariate analytical methods are applied.

One of the main challenges that face the modern wine sciences is how to optimise grape and wine production in order to have a minimum environmental footprint, lower production costs, as well as how to improve or maintain the quality of the wine produced. It has been generally accepted that a single analytical technique will not provide sufficient information about the wine metabolome and therefore a holistic-omics approach is suggested for a more comprehensive analysis. Metabolomics is an emerging field in grape and wine research enabling chemical and biochemical profiling of samples (e.g. grapes, wine) in order to obtain insight into its biological characteristics and properties. By means of a literature review of the most recent published reports on the use of the metabolomics approach, the aim of this paper is to provide with an overview on the use of this approach in grape and wine research. Most of the studies presented in this review have highlighted the importance of metabolomics in wine science, as well as emphasised on the need of a multidisciplinary team approach where the participation of scientists from different disciplines such as biology, biochemistry, chemistry and chemometrics (mathematics and statistics) being equally important to deliver successful and reliable data, in order to improve our knowledge about wine. The combination of different techniques provides both the research and industry with powerful and complementary tools that differ from the conventional routine methods currently in use by the grape and wine industry.

The aim of this study was to evaluate the use of the rapid visco analyser (RVA) instrument as a tool to sequentially analyse barley (Hordeum vulgare) malting varieties in order to visualise and interpret the effect of amylose and amylose complexes on its pasting properties. The RVA sequential profiles derived from the barley samples analysed showed a large peak (peak viscosity, PV) at the start of each cycle alternating with viscosity troughs during the hot paste viscosity cycle. The sequential cycles caused a slight decrease in both PV and (final) FV values in all barley varieties analysed. The addition of silver nitrate to the barley flour samples tends to slightly increase the PV value independently of the time of the analysis. The development of this methodology will provide with better tools to study starch pasting properties as well as to study the interactions between amylose and amylopectin with other compounds in various malting varieties.

Wine quality depends upon the composition of the grapes used in its production, which in turn depends on the weather and soil of the growing region together with viticultural practices. Region is used by many winemakers as a proxy for quality but objective quality measures are lacking. This study examined the compositional aspects of Chardonnay wines produced with berries from different regions. Through descriptive analysis, distinct sensory profiles were recognised for three diverse regions in South Australia (Adelaide Hills, Eden Valley, Riverland), which helped to pinpoint compounds relating to higher- and lower-quality Chardonnay wines. Correlations between the content of elements, fatty acids, free volatiles and conjugated glycosides in berries from different quality levels, and the composition of their corresponding wines, were investigated. Higher berry concentrations of linalool, (E)-linalool oxide, (Z)-3-hexen-1-ol, decanoic acid, vitispirane, Cu, Zn, and behenic acid, and lower °Brix and pH levels were related to higher quality wines.

In recent decades, research in barley has led to improvements in several biochemical and chemical characteristics (e.g. protein, starch, β glucans) associated with malt composition and end product quality (e.g. beer). Although lipids and fatty acids (FA) represent between 1 to 3% of the grain weight (dw), they can play an important role in barley grain and malt derived materials. However, the role of lipids and FA in both barley and malt quality is still not well understood. The aim of this article is to provide an overview on the role of lipids and FA in the chemical and industrial properties of barley grain, malt and wort.

The increasing use of hand-held or portable infrared instruments (near infrared and mid infrared (MIR)), the development of new algorithms and the increasing use of chemometrics have changed the way that infrared spectroscopy is used to measure different properties in soils, allowing the measurement of samples in the field (on-the go). However, key important aspects on the use of near infrared spectroscopy to analyse soil samples containing high moisture levels still not well understood. A brief summary of the main issues related with applications of NIR spectroscopy to measure soil samples in the field are discussed in this article.

Consumer awareness of the health value of native and tropical fruits and its products, is increasing, where demands for new applications are driving food industry to find novel applications of these fruits as functional ingredients. Kakadu plum fruit (Terminalia ferdinandiana) is endemic to Australia and has been used as a functional food or ingredient. This fruit is sold as whole fruit, puree or powder. Critical to the commercialization of this fruit is the development and use of methods and tools to better monitor and understand the quality of these products throughout the value chain. The aim of this study was to evaluate four scanning positions used to collect near infrared (NIR) spectra of Kakadu plum fruits wild harvested, in order to develop a rapid and high throughput method to monitor fruit chemical composition. A portable NIR instrument (Micro-NIR, Viavi, Milpitas, CA, USA) was used to collect the spectra of whole fruit (four positions) samples from the Kimberley region in Western Australia. The NIR data was analysed using principal component analysis (PCA) and partial least squares (PLS) regression models for moisture and total soluble solids. The results showed that the scanning position affected the performance of the models (standard error of cross validation). It was concluded that NIR spectroscopy is a promising method to assure the integrity of the value chain of these products. However, a more robust protocol must be defined when whole fruit are analysed.

The attachment of single-celled organisms, namely bacteria and fungi, to abiotic surfaces is of great interest to both the scientific and medical communities. This is because the interaction of such cells has important implications in a range of areas, including biofilm formation, biofouling, antimicrobial surface technologies, and bio-nanotechnologies, as well as infection development, control, and mitigation. While central to many biological phenomena, the factors which govern microbial surface attachment are still not fully understood. This lack of understanding is a direct consequence of the complex nature of cell-surface interactions, which can involve both specific and non-specific interactions. For applications involving micro- and nano-structured surfaces, developing an understanding of such phenomenon is further complicated by the diverse nature of surface architectures, surface chemistry, variation in cellular physiology, and the intended technological output. These factors are extremely important to understand in the emerging field of antibacterial nanostructured surfaces. The aim of this perspective is to re-frame the discussion surrounding the mechanism of nanostructured-microbial surface interactions. Broadly, the article reviews our current understanding of these phenomena, while highlighting the knowledge gaps surrounding the adhesive forces which govern bacterial-nanostructure interactions and the role of cell membrane rigidity in modulating surface activity. The roles of surface charge, cell rigidity, and cell-surface adhesion force in bacterial-surface adsorption are discussed in detail. Presently, most studies have overlooked these areas, which has left many questions unanswered. Further, this perspective article highlights the numerous experimental issues and misinterpretations which surround current studies of antibacterial nanostructured surfaces.

The most commonly used spectroscopic techniques in food analysis are atomic and molecular spectroscopy. The vast majority of the applications of molecular spectroscopy in food are using near- and mid-infrared spectroscopy. However, the advent of new instrumentation and sample presentation alternatives has led to an increase in the use of ultraviolet-visible (UV-Vis) spectroscopy for the analysis of food. This chapter reviews the basic concepts of UV-Vis spectroscopy and provides examples of this technique applied to the analysis of different food matrices (e.g., meat, milk, coffee, wine, and olive oil).

International audience; In recent years, decreased cost, miniaturisation and advances in computing power and data processing software have led to widespread introduction of Fourier-transform (FT) spectrometers across different disciplines. In this review, applications of FT mid infrared (FT-MIR) spectroscopy are summarised covering the analysis of fresh fruit and vegetables, and some of their processed products (juices, jam, oil, wine). The paper also outlines basic principles of vibrational spectroscopy in the MIR region, using sugars and acids in fruit juices as exemplars of spectral interpretation. Laboratory-based spectrometers, FT-MIR microspectroscopy for high-resolution mapping and portable, hand-held units for field work are described. Applications involving these systems, which extend to more than 40 genera, and more than 40 different crop attributes, include; assessing the maturity or quality attributes of produce, screening progeny from breeding programmes, determination of bioactive contents and plant metabolites, determining the extent of adulteration and authenticating products for type or geographic location, and localisation of metabolites within plant cells. Principles outlining best-practice for developing calibration models in fruit and vegetable-based systems are also included.

The current knowledge of the main factors governing livestock, crop and plant quality as well as yield in different species is incomplete. For example, this can be evidenced by the persistence of benchmark crop varieties for many decades in spite of the gains achieved over the same period. In recent years, it has been demonstrated that molecular breeding based on DNA markers has led to advances in breeding (animal and crops). However, these advances are not in the way that it was anticipated initially by the researcher in the field. According to several scientists, one of the main reasons for this was related to the evidence that complex target traits such as grain yield, composition or nutritional quality depend on multiple factors in addition to genetics. Therefore, some questions need to be asked: are the current approaches in molecular genetics the most appropriate to deal with complex traits such as yield or quality? Are the current tools for phenotyping complex traits enough to differentiate among genotypes? Do we need to change the way that data is collected and analysed?

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.

Variations in the amount and rates of water uptake influence the seed hydration as well as the modification of the endosperm for industrial uses (e.g., malting). The aim of this study was to investigate and interpret absorption frequencies in the mid infrared (MIR) region associated with water uptake in whole seeds, husk and endosperm of barley seeds during the initial period of soaking in water. Partial least squares (PLS) regression models for the prediction of water uptake in the set of samples yield a coefficient of determination (R2) and a standard error in cross validation of 0.75 and 2.57 (% w/w), respectively. The biological implications of this study are that the first stages of germination can be monitored using the information derived from the MIR spectra. These results also demonstrated that whole seeds, endosperm and husk derived from the same variety or genotype have different patterns in the MIR region.

Unprocessed barley is known to contain relatively high levels of antioxidants, which play a critical role in human health and the preservation of food and drink products. However, there are limited data on how the antioxidant levels in barley are affected by malting, and whether the level of antioxidants in the processed malt differs between barley varieties. This study aimed to determine the levels of individual vitamin E isomers, total vitamin E content and total antioxidant capacity before, during and after malting in 12 covered and two hulless barley genotypes. Vitamin E content and antioxidant capacity were determined by high-performance liquid chromatography (HPLC) and ability to scavenge DPPH radicals, respectively. The vitamin E content of most genotypes was reduced after steeping, germination and kilning compared with the unprocessed samples. However, the antioxidant capacity in the malt was higher than in the unprocessed samples for the majority of the genotypes. While there was variation in the percentage change in antioxidant capacity between varieties, the antioxidant capacity of samples after malting was directly correlated with their antioxidant capacity before processing (r=0.9, n=14, p

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 objective of the present study was to develop a simple, rapid and accurate method for the determination of glucose, fructose, maltose and sucrose in barley malt using attenuated total reflectance (ATR) mid-infrared (MIR) spectroscopy. A total of 100 malt samples were analysed using an ATR-MIR instrument and the concentration of individual sugars determined using HPLC. Partial least squares (PLS) regression models yielded a coefficient of determination in cross validation (R 2) and standard error in cross validation (SECV) of 0.64 (1.38 mg mL−1), 0.84 (0.12 mg mL−1), 0.80 (8.3 mg mL−1), and 0.60 (0.91 mg mL−1) for glucose, fructose, maltose and sucrose, respectively. This study demonstrated the potential benefits of ATR-MIR spectroscopy for the rapid measurement of the concentration of individual sugars in malt samples sourced from different commercial barley varieties, harvest seasons and localities.

Foodomics has been defined by as a new discipline that studies both the food and nutritional domain by applying and combining cutting-edge analytical technologies and multivariate data analysis. Pioneered by physicists and chemists, methods based in infrared spectroscopy have traditionally been used for the identification of molecular entities in several food matrices. Infrared spectroscopy embraces a number of techniques allowing the analysis of different type of samples (e.g. liquid, solids, pastes), determining specific applications such as attenuated total reflection (ATR, ATR-MIR), Fourier transform (FT-MIR, FT-NIR), transmitance (T), transflectance or reflectance (R), diffuse reflectance (DF).

The characteristics of the starch granule such as swelling, breakdown and retrogradation in large determines the texture and stability of starchy foods. However, other characteristics of the grain and/or the presence or addition of chemical compounds to the grain/food matrix can modify or alter these properties. The aim of this study was to evaluate the effect of the addition of an emulsifier (Tween 20 and 80) on the pasting properties of barley grain and malt using the rapid visco analyser (RVA). A decrease in peak viscosity (PV, cP), breakdown (B, cP) and final viscosity (FV, cP), while an increase in time to peak (TTP, min) and pasting temperature (PT, °C) as consequence of the addition of Tween 20 was observed. However, this trend was not the same for all the varieties analysed. Overall, these results showed that complex between sugars and lipids are present in barley flour and malt. The practical implications of this study are related with the fact that starch alone (amylose and amylopectin) might not be necessarily the only main driver of malt quality in barley.

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.

Methylglyoxal (2-oxopropanal) is a compound known to contribute to the non-peroxide antimicrobial activity of honeys. The feasibility of using infrared spectroscopy as a predictive tool for honey antibacterial activity and methylglyoxal content was assessed. A linear relationship was found between methylglyoxal content (279-1755 mg/kg) in Leptospermum polygalifolium honeys and bacterial inhibition for Escherichiacoli (R(2) = 0.80) and Staphylococcusaureus (R(2) = 0.64). A good prediction of methylglyoxal (R(2) 0.75) content in honey was achieved using spectroscopic data from the mid infrared (MIR) range in combination with partial least squares regression. These results indicate that robust predictive equations could be developed using MIR for commercial application where the prediction of bacterial inhibition is needed to 'value' honeys with methylglyoxal contents in excess of 200mg/kg.

Most of the spectroscopy applications present in literature rely on spot measurements using infrared (near or mid) or visible ranges. More recently, a diverse range of hyperspectral devices, including cameras and spectral imaging, can acquire single or multiple images at selected wavelengths, expanding the possibilities of analysis and enhancing the potential for detection of specific quality attributes in an extensive range of crops and horticultural products. This chapter provides a general overview of the fundamentals of vibrational spectroscopy and describes the main methods and techniques applied in crop and plant analysis.

Fraud is a billion dollar business which affect the food industry worldwide. The concerns on this practice are not limited to financial repercussions to the manufacture company, but also with the use of inferior quality materials of the adulterated products as these products can severely influence human health. Recently, considerable scientific effort has been devoted to creating robust and reliable methodologies of analysis to be implemented. The need for rapid, accurate and sensitive detection methods to detect and monitor adulterations in foods has been one of the main objectives in the food industry. Vibrational spectroscopy and the role of chemometrics in extracting chemically-relevant information have led to the development of several applications in the field of fraud adulteration.

One of the main food risks gaining attention from industry, governments, and standards-setting organizations is fraud conducted for economic gain by food producers, manufacturers, processors, distributors, or retailers. The infrared (IR) spectrum originates from the absorption of different frequencies by a sample positioned in the path of an IR beam (e.g. near or mid infrared beams) determining the IR fingerprint of a given sample. This fingerprint signal contains most of the relevant (chemical, physical, process) information related to the sample allowing tracing its origin. The aim of this article is to highlight different applications of the main vibrational spectroscopy (near, mid and Raman spectroscopy) techniques as tools to assess fraud and counterfeit issues in foods. Examples of such applications include samples of milk, fish, meat, olive oil as well as other agricultural products and foods.

Extensive research has been conducted for understanding starch structure and composition in relation to grain composition and quality. However, less effort has been dedicated to studying the main role of other non-structural carbohydrates and their interactions with other molecules such as glycolipids and lipopolysaccharides. The formation of complexes between amylose and lipids has also been highlighted, indicating that these complexes can modulate the different biochemical, chemical and physical properties of different cereal grains. Recent studies also suggested that other sugars (e.g., sucrose) can be associated with lipids in the form of lipopolysaccharides, glycol-glycerolipids or sugar esters having an important role in food properties (e.g. gelatinization of starch, formation of emulsions). The aim of this study was to investigate the presence of sugar fatty esters in barley malt using mid-infrared (MIR) spectroscopy. The results from this study indicated the existence of correlations between the area in the MIR related to esters (1800–1600 cm−1) and malt extract, showing statistically significant (p 83%). The results of this study also indicated that sugar fatty esters or esters might play a role in explaining differences in malt composition between different barley varieties.

Although lipids and fatty acids (FA) represent only 1-3% of the grain weight, they can play an important role in regulating, modulating, and determining several chemical and physical properties of the grain and corresponding malts. The aim of this study was to evaluate the relationships between the content of FA in grain, malt, and wort with malt quality characteristics such as hot water extract (HWE) and apparent attenuation limit (AAL) in different commercial malting barley varieties. High and positive correlations were found between myristic acid and HWE (r = 0.71) and between stearic acid and AAL (r = 0.76), with intermediate correlations between palmitic, oleic, linoleic, and linolenic acids and AAL (r = >0.50) in grain. High and negative correlations were found between stearic acid and HWE (r = -0.66), and high and negative correlations were found between palmitic (r = -0.74) and linoleic (r = -0.60) acids and AAL in the wort. Results from this study showed that lipids, as well as the combination of unsaturated and saturated FA, might play a role in determining differences in HWE and AAL between the barley varieties analyzed. No clear evidence on HWE was observed when grain and malt samples from the same variety were compared. These results indicated that lipids and FA should be considered together with starch properties to explain differences between HWE and AAL.

The production of several agricultural products and foods are linked with fermentation. Traditional methods used to control and monitor the quality of the products and processes are based on the use of simple chemical analysis. However, these methods are time-consuming and do not provide sufficient relevant information to guarantee the chemical changes during the process. Commonly used methods applied in the agriculture and food industries to monitor fermentation are those based on simple or single-point sensors, where only one parameter is measured (e.g., temperature or density). These sensors are used several times per day and are often the only source of data available from which the conditions and rate of fermentation are monitored. In the modern food industry, an ideal method to control and monitor the fermentation process should enable a direct, rapid, precise, and accurate determination of several target compounds, with minimal to no sample preparation or reagent consumption. Here, state-of-the-art advancements in both the application of sensors and analytical tools to monitor beverage and food fermentation processes will be discussed.

Seeds from the myxospermous species Plantago ovata release a polysaccharide-rich mucilage upon contact with water. This seed coat derived mucilage is composed predominantly of heteroxylan (HX) and is utilized as a gluten-free dietary fiber supplement to promote human colorectal health. In this study, a gamma-irradiated P. ovata population was generated and screened using histological stains and Fourier Transform Mid Infrared (FTMIR) spectroscopy to identify putative mutants showing defects in seed coat mucilage HX composition and/or structure. FTMIR analysis of dry seed revealed variation in regions of the IR spectra previously linked to xylan structure in Secale cereale (rye). Subsequent absorbance ratio and PCA multivariate analysis identified 22 putative mutant families with differences in the HX IR fingerprint region. Many of these showed distinct changes in the amount and subtle changes in structure of HX after mucilage extrusion, while 20% of the putative HX mutants identified by FTMIR showed no difference in staining patterns of extruded mucilage compared to wild-type. Transcriptional screening analysis of two putative reduced xylan in mucilage (rxm) mutants, rxm1 and rxm3, revealed that changes in HX levels in rxm1 correlate with reduced transcription of known and novel genes associated with xylan synthesis, possibly indicative of specific co-regulatory units within the xylan biosynthetic pathway. These results confirm that FTMIR is a suitable method for identifying putative mutants with altered mucilage HX composition in P. ovata, and therefore forms a resource to identify novel genes involved in xylan biosynthesis.

Improving grain yield and adaptation is achieved by synchronising crop phenology with the environment. Phenology research is complex and encounters analytical challenges in characterising genotype x environment (GxE) interactions. This paper presents a simple approach that helps to explain the environmental drivers of phenology. Photoperiod and temperature are major environmental cues for expression of crop developmental genes, and sensitivity to photoperiod is thought to be the major cause of maturity differences among Australian spring barley varieties. However, temperature and photoperiod show similar seasonal trends and strong autocorrelation makes it difficult to distinguish their relative importance in crop development. Partial Least Squares regression (PLS) was developed to handle large data sets with many correlated explanatory variables and only one dependent variable. Across 35 environments encompassing a wide range of temperature and photoperiod regimes in southern Australia, a PLS model described more than 90 % of the phenotypic variation in time to anthesis of three adapted barley cultivars. The PLS outputs defined the critical periods when photoperiod and temperature were most influential, and revealed that temperature effects are of equal or greater importance than photoperiod in determining anthesis date, which is a new finding for genotypes adapted to Australian environments. Insight into the previously elusive differential responses to changes in daily average, maximum, and minimum temperatures will assist in developing flowering models for growers that are more accurate, and assist breeders in the genetic dissection of phenology for target environments.

Extensive research has been carried out to study and characterise different properties of alcoholic beverages using spectroscopy methods. Although UV-VIS spectroscopy is being used for the routine analysis of several beverages and foods, it has not been extensively used as a high throughput method. The objective of this study was to evaluate the application of derivatives to interrogate the UV-VIS spectra of gin samples to monitor changes related with storage conditions. Samples were analysed using an UV-VIS (200–800 nm) spectrophotometer with 1 cm path length. The raw spectra, second, third and fourth derivatives were used to analyse and interpret the UV-VIS spectra related to storage conditions. The results of this study indicated that the use of derivatives (third and fourth) as pre-process method to the UV-VIS spectra of gin samples allowed for a better identification of wavelengths as well as interpretation of the spectra associated with the different storage conditions.

Starch is the major component of cereal grains and starchy foods, and changes in its biophysical and biochemical properties (e.g., amylose, amylopectin, pasting, gelatinization, viscosity) will have a direct effect on its end use properties (e.g., bread, malt, polymers). The use of rapid and non-destructive methods to study and monitor starch properties, such as gelatinization, retrogradation, water absorption in cereals and starchy foods, is of great interest in order to improve and assess their quality. In recent years, near infrared reflectance (NIR) and mid infrared (MIR) spectroscopy have been explored to predict several quality parameters, such as those generated by instrumental methods commonly used in routine analysis like the rapid visco analyser (RVA) or viscometers. In this review, applications of both NIR and MIR spectroscopy to measure and monitor starch biochemical (amylose, amylopectin, starch) and biophysical properties (e.g., pasting properties) will be presented and discussed.

Malting barley is a process that has been profusely studied and is known to be influenced by several physical and biochemical properties of the grain. In particular, the amount of material that can be extracted from the malt (malt extract) is an important measure of brewing performance and end quality. The objectives of this study were (a) to compare the time course of hydrolysis of different malting barley (Hordeum vulgare L) varieties and (b) to evaluate the usefulness of mid-infrared (MIR) spectroscopy as high-throughput method to monitor malt hydrolysis. Differences in the pattern of hydrolysis were observed between the malt samples analyzed where samples from the same variety that have similar hot water extract (HWE) values tend to have the same pattern of hydrolysis. Principal component score plots based on the MIR spectra showed similar results. Partial least-squares discriminate analysis (PLS-DA) was used to classify malt samples according to their corresponding variety and time course of hydrolysis. The coefficient of determination (R(2)) and the standard error of cross validation (SECV) obtained for the prediction of variety and time course of hydrolysis were 0.67 (1.01) and 0.38 (19.90), respectively. These differences might be the result of the different composition in sugars between the barley varieties analyzed after malting, measured as wort density and not observed when only the HWE value at the end point is reported. This method offers the possibility to measure several parameters in malt simultaneously, reducing the time of analysis as well as requiring minimal sample preparation.

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.

Near infrared (NIR) reflectance spectroscopy combined with chemometrics was used to classify toasted and untoasted oak wood shavings sourced from two countries (France and USA). Oak wood shaving samples (n = 96) were scanned in the NIR region (680–2,500 nm) using a monochromator instrument operating in reflectance mode. Principal component analysis, partial least squares discriminant analysis (PLS-DA) and linear discriminant analysis (LDA) were used to classify the samples according to their country of origin and level of toasting. Full cross validation (leave-one-out) was used as the validation method when classification models were developed. Correct classification rates of 83, 87 and 100 % for samples sourced from USA, France and toasted treatment were obtained using PLS-DA. For LDA, correct classification rates of 80.4, 85 and 100 % were achieved for samples sourced from USA, France and toasted treatment, respectively. These results demonstrated the ability of NIR spectroscopy to discriminate between oak wood shavings sourced from two different countries and two levels of toasting.

The aim of this study was to evaluate the use of attenuated total reflectance and mid infrared (ATR-MIR) spectroscopy and to understand the gelatinization and retro-gradation of flour barley samples and the relationship with malting quality. Samples were sourced from two commercial barley varieties exhibiting high hot water extract (HWE) namely Navigator (n = 8), and Admiral (n = 8). Samples were analysed using the Rapid Visco Analyser (RVA) and ATR-MIR analysis. These results showed that ATR-MIR spectroscopy is capable of characterising gel samples derived from barley flour samples having different malting characteristics. Infrared spectra can effectively represent a ‘fingerprint’ of the sample being analysed and can be used to simplify and reduce analytical times in the routine methods currently used.

Although both near infrared (NIR) spectroscopy and mid infrared (MIR) spectroscopy combined with multivariate data analysis (MVA) have been extensively used to measure chemical composition (e.g. protein, moisture, oil) in a wide number of grains few reports can be found on the use of this methods for varietal discrimination and traceability of cereals. In this overview applications of NIR spectroscopy and MIR spectroscopy combined with multivariate data methods such as principal component analysis (PCA), partial least squares discriminant analysis (PLS-DA), linear discriminant analysis (LDA) to aid on the authentication and traceability of cereals are discussed.

Vibrational spectroscopy encompasses a number of techniques and methods including ultra-violet, visible, Fourier transform infrared or mid infrared, near infrared and Raman spectroscopy. The use and application of spectroscopy generates spectra containing hundreds of variables (absorbances at each wavenumbers or wavelengths), resulting in the production of large data sets representing the chemical and biochemical wine fingerprint. Multivariate data analysis techniques are then required to handle the large amount of data generated in order to interpret the spectra in a meaningful way in order to develop a specific application. This paper focuses on the developments of sample presentation and main sources of error when vibrational spectroscopy methods are applied in wine analysis. Recent and novel applications will be discussed as examples of these developments.

Attenuated total reflectance (ATR) mid-infrared (MIR) spectroscopy was evaluated to measure fatty acids (FA) and total lipids in intact seed barley (Hordeum vulgare) samples. Results from this study demonstrated the capability of ATR-MIR spectroscopy coupled with partial least squares (PLS) regression to measure FA non-destructively in intact barley seeds. The coefficients of determination in cross validation (R2) and the standard error of cross validation (SECV) were 0.76 and 0.004 g 100 g−1 for stearic, 0.75 and 0.037 g 100 g−1 for oleic, 0.45 and 0.02 g 100 g−1 for palmitic acids, and 0.89 and 0.13 g 100 g−1 for total lipids, respectively. The practical implications of this study showed that ATR-MIR spectroscopy confer valuable benefits for the grain industry and in particular in breeding programs as a non-destructive high throughput method.

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...

Compared to traditional laboratory methods, spectroscopic techniques (e.g., near infrared, hyperspectral imaging) provide analysts with an innovative and improved understanding of complex issues by determining several chemical compounds and metabolites at once, allowing for the collection of the sample “fingerprint”. These techniques have the potential to deliver high-throughput options for the analysis of the chemical composition of grapes in the laboratory, the vineyard and before or during harvest, to provide better insights of the chemistry, nutrition and physiology of grapes. Faster computers, the development of software and portable easy to use spectrophotometers and data analytical methods allow for the development of innovative applications of these techniques for the analyses of grape composition.

Agronomic and breeding innovations are essential to support grain production whilst avoiding over-fertilisation and excess reactive nitrogen in some agroecosystems, and chronic under-fertilisation and mining of soil organic matter in others. Based on the well-established negative correlation between yield per unit land area and intraspecific competitive ability, we hypothesised that the yield-nitrogen curve at the centre of fertiliser decisions mirrors the competition-nitrogen curve. A factorial study combining six wheat cultivars, two locations, two sowing dates and four nitrogen rates supported our hypothesis in early-sown crops where intraspecific competition for nitrogen decreased, and competition for radiation and water increased with increasing availability of nitrogen. In late-sown crops, high temperature favouring fast development, short plants and smaller canopies overrode competition for resources as the driver of grain yield. The implication is that genetic and agronomic reduction of intraspecific competition can improve yield per unit available nitrogen.

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.

The aim of this study was to evaluate the feasibility of using attenuated total reflectance mid-infrared (ATR-MIR) spectroscopy to predict the fructan content in both barley and malt flour samples. Samples (n = 60) were sourced from commercial and experimental barley grain varieties and their corresponding malts. The fructan content in grain and malt flour was determined using the enzymatic kit from Megazyme (K-FRUC, Megazyme International Ireland). Samples were scanned in a MIR instrument using an ATR single bounce cell (Bruker Optics, Germany). The coefficients of determination in cross-validation (R2) and the standard error of cross-validation (SECV) obtained for the prediction of the fructan content in the calibration set were 0.76 and 0.20%, respectively. The residual predictive deviation (RPD = SD/SECV) value obtained was 2.3, indicating that these calibrations can be used for qualitative determination of the fructan content (e.g. low, medium and high) in the set of samples analysed. This study showed that ATR-MIR spectroscopy might be used as approximate estimates of the true fructan concentration in barley and malt in order to rank samples (low, medium, high) in the context of a breeding program.

Steeping is the first operation of malting and its purpose is to increase the water content of the grain up to 43-46%; however, such a simple step encompasses several metabolic processes that affect germination and the final malt quality. The aim of this study was to evaluate the effect of initial grain protein (GP) content and starch pasting properties, measured using the Rapid Visco Analyser (RVA) on water uptake in different barley varieties. The partial least squares (PLS2) regression algorithm was used to compare the two data matrices, the independent block of variables X (RVA data and GP) and the dependent block Y (water uptake at different steeping times). The first two PLS2 loadings explained 65 and 23% of the total variation in water uptake in the barley samples. Water uptake at 1 and 2h was poorly explained by the PLS2 models, while after 5h the models explained more than 40% of the variability. The results from this study showed that, although a relationship between GP and water uptake exists, it is not universal for all the varieties, indicating that the relationship between GP and water uptake is varietal dependent.

Knowledge of the chemical and structural differences between barley (Hordeum vulgare L.) varieties and breeding lines might lead to an understanding of the reasons for these differences among genotypes in relation to their malting properties. The aim of this study was to evaluate the use of attenuated total reflectance mid infrared (ATR-MIR) spectroscopy combined with univariate and multivariate methods as a high throughput screening tool to phenotype single seeds of barley. Varieties that yield high malting quality (hot water extract (HWE)>80%) showed relatively high non-structural carbohydrates (e.g. starch) to protein and non-structural to structural (e.g. cellulose) carbohydrates ratios compared with those samples having moderate HWE (78%

Parts manufactured by Wire and Arc Additive Manufacture (WAAM) can have significant residual stress and distortion, as well as large grain sizes. To overcome these problems, each layer on a linearly deposited steel WAAM part was rolled with either a ‘profiled’ roller, which had a similar shape to the deposited layer, or a ‘slotted’ roller, in which a groove prevented lateral deformation. Both rollers reduced the distortion and surface roughness, but the slotted roller proved more effective – eliminating the distortion. The residual stresses in the rolled WAAM parts were measured and were lower than those in the unrolled control specimen – particularly adjacent to the baseplate. Rolling also induced additional grain refinement when the rolled material was reheated during the subsequent deposition pass. The application of rolling may be a key technology for enabling implementation of WAAM on large-scale structures.