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Colloids are responsible for undesirable haze formation in wine. Here, we characterized 20 colloid batches after isolation by ultrafiltration of musts and wines from five cultivars obtained from four consecutive vintages. Polysaccharide and protein concentrations of the colloids ranged from 0.10 to 0.65 and 0.03 to 0.40 mg/L, respectively. Protein profiling in must and wine colloids by fast protein liquid chromatography (FPLC) and liquid chromatography–high-resolution tandem mass spectrometry (LC–HR-MS/MS) analyses indicated a lower number of proteins in wine than in must colloids. Molar mass distribution analyses revealed all colloids to consist of two carbohydrate- (424–33,390 and 48–462 kg/mol) and one protein-rich (14–121 kg/mol) fractions. The observed barely negative ζ potentials (−3.1 to −1.1 mV) in unstable wines unraveled that colloid instability might be partly related to their poor electrostatic repulsion in the wine matrix. ζ potentials of the colloids from pH 1 to 10 are also presented. Our data support future developments to eliminate haze-forming colloids from wine.

Einkorn (Triticum monococcumL.), emmer (T. dicoccumL.), and spelt (T. speltaL.) are old‐world hulled wheat crops currently receiving renewed interest of consumers, bakers, millers, and farmers. Our objectives were to (i) compare einkorn, emmer, and spelt with bread (T. aestivumL.) and durum wheat (T. durumL.) regarding their main agronomic and quality traits, (ii) elaborate the heritability and correlation among these traits across the wheat species, and (iii) draw conclusions about optimized farming and processing practices for einkorn, emmer, and spelt. For this purpose, field trials were conducted at four diverse German locations, where 15 recent varieties were grown for each wheat species. Mean grain yields of spelt, emmer, and einkorn were 37, 55, and 62% lower than that of bread wheat. Furthermore, einkorn, emmer, and spelt plants were 30 cm taller than bread and durum wheat. Consequently, to avoid lodging, farmers should aim at reducing the plant height of hulled wheats. Despite their high protein content, the protein quality of hulled wheat determined as sedimentation volume was low from a classical bread wheat point of view. However, adapting classical baking procedures enables the production of high quality breads from einkorn, emmer, and spelt in addition to the development of alternative products like breakfast cereals or excellent specialty breads.