Grain characteristic, chemical composition, and functional properties of rye were measured in 19 different cultivars grown in one location in up to 3 years. The cultivars included 8 adapted hybrids, 7 adapted population cultivars, and 4 nonadapted population cultivars. The results showed a significant influence of both harvest year and genotype on grain characteristics, chemical composition, and functional properties of the grain. Multivariate data analysis confirmed that the variations in the data were explained by yearly and genotype differences. Calculations of variance components showed that the variations in plant height, harvest yield, and protein content were mainly due to genotype differences and to a lesser extent to differences among harvest years. The kernel weight, hardness index, and content of dietary fiber components, however, were more strongly influenced by the harvest year than by the genotype. Differences in starch properties measured by falling number (FN), amylograph peak viscosity, and temperature at peak viscosity were more strongly influenced by harvest year. The water absorption was strongly influenced by genotype effects, compared to yearly differences. FN and amylograph peak temperature were positively correlated (r ) 0.94). No correlation was found between the water absorption and the relative proportion of water-extractable arabinoxylan (AX) compared to the total AX content. However, the degree of ferulic acid cross-linking showed a negative correlation (r ) -0.70) with the water absorption.

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A new germinative two-dimensional classification plot fully compatible to the current EBC analyses (EBC methods 3.5-3.7) is proposed for malting barley based on separate estimates for "vigour" (24 h germination) as abscissa with limits at 70% and 30% and for "viability" (72 h germination) as ordinate with limits at 98% and 92%. Early detection of germination by image analysis was improved by utilising the auto fluorescence of the root cap. The seven hierarchical germinative classes visualise the quality differences in a consistent way, ordering classes according to falling extract % and increasing wort ␤-glucan (mg/L).It was surprising to discover that significant barley Near Infrared Transmission (NIT) spectroscopy based Partial Least Squares Regression prediction models for "vigour" and "viability" were obtained after removing the PLSR outliers. The majority of these were found to be low in vigour.It was concluded after experimental validation that the physical-chemical structure of the seed, reflected by the correlation of the barley NIT spectral fingerprints to germination speed, is connected to the availability of substrate for germ growth. This is another aspect of the speed of malt modification.An automated combination instrument for measuring physicalchemical and seed germination parameters is suggested for quality control and to establish an on-line NIT calibration network for integrated germinative and malting quality classification.

The physiological and physical-chemical basis of barley germination was studied. Vigour was defined as germination percentage after 24 h and viability as that of 72 h. The barley samples were analysed under germination capacity and energy conditions after harvest and after long time cold storage at 7°C three-six years. These parameters were each correlated by Partial Least Squares Regression (PLSR) to two separate multivariate data sets: a set of ten physical-chemical parameters and to Near Infrared Transmission (NIT) spectra (850-1050 nm). Surprisingly high correlation coefficients for each of these two data sets were obtained especially with vigour, extract (%) and ␤-glucan in wort (mg/L) when outliers with viability below 92% were removed. Hard, slowly germinating seeds were more resistant to decay in vigour and viability storage than soft seeds. This change could be predicted by PLSR correlations to the two physicalchemical multivariate methods. Vigour was a more sensitive indicator for the ability to store than viability. The steep criterion was also found to have a physical-chemical basis. The results indicate that NIT calibrations can be used to predict vigour in malting grade barley.

In earlier studies concerning vigour, where subsamples are heat‐treated before germination there was found heat‐sensitive as well as heat‐resistant barley samples. The vigour model developed by Ellis and Roberts and further developed at Carlsberg, could only describe the heat‐sensitive barleys. Seventeen samples of the “Alexis” variety grown widely in Europe were collected from the EBC trials in 1994 in order to see if heat resistance in barley was influenced by different growing conditions. We found both heat‐sensitive samples following the vigour model as well as pronounced heat‐resistant samples, but these were not divided according to growing conditions. The germination curves dependent on heat treatment and germination time were evaluated by Principal Component Analysis (PCA). Heat‐resistant barley samples could be differentiated from heat‐sensitive samples already after ½ h of heat treatment at 68°C (12% moisture) and after 3 days of germination. The barley samples were analysed with regard to malting quality. The PCA evaluation of the data divided the samples according to growing location, mainly due to differences in protein and β‐glucan. However, the malting analyses could not describe the differences in heat resistance and sensitivity of the barleys. The biochemical background of the heat resistance found is discussed on the basis of literature. Our findings should give an experimental basis for exploiting a biochemical principle for heat resistance, which is formed during grain filling and consumed during storage and germination.