The influence of chemical and biological acidification on dough rheological properties and bread quality has been investigated. Two different flour types were used. Dough was chemically acidified with lactic acid. Two types of biologically acidified dough were prepared: dough with dry sourdough and with a Lactobacillus brevis preferment. Wheat dough rheological properties were investigated using the Farinograph, Extensograph and Amylograph. The baking response was also determined using standard baking tests. Addition of acidifiers resulted in firmer doughs with less stability, decreased extensibility and decreased gelatinisation maximum. The biological acidifiers increased the bread specific volume. Lactic acid addition had no influence on bread specific volume. In general, biological and chemical acidification decreased bread hardness. The addition of dry sourdough significantly decreased the lightness and increased the yellowness and redness of the bread crumb. The crust chroma, hue angle and brownness index were significantly changed by addition of acidifiers. * Values are mean ± SD of four independent determinations; mean values followed by common letter within the same column are not significantly different (P < 0.05). † Control, control dough; I and II, flour types: T-550 and T-110, respectively; LAB, biologically acidified dough by addition of sourdough prepared with Lactobacillus brevis L-75; DS, biologically acidified dough by addition of dry sourdough; LA, chemically acidified dough by addition of lactic acid. Properties of acidified bread D. K. Komlenić et al.

Today’s beer differs in many ways from the original hazy brew made from grains and water left in the sun to ferment. The development of brewing procedures introduced filtration and colloidal stabilization as key elements in beer preservation and stability. Colloidal stability of beer is the most important factor in beer quality. Colloidal particles significantly shorten beer’s storage time, but most importantly, also influence its appearance. Colloidal stabilization involves one or more procedures that are applied at different stages during production and result in colloidal stability of the final product. Beer is considered to be colloidal stable if it can be stored for several months at 25 °C without exhibiting any changes in composition or other properties; specifically, beer has to be able to remain clear without any signs of precipitation. Since colloidal stability is of primary importance for the consumer, retail requirements have resulted in many solutions for this issue. Stabilization agents have to be reliable during the filtration and stabilization processes. Additionally, renewable agents are highly desirable. The level of colloidal stability required depends on the desired storage time and temperature after the beer has been packed. Consumers have higher and higher expectations that the industry has to follow.

No abstract

Pumpkin seed oil press cake (PSOPC) is a by‐product of pumpkin oil production, and after cold pressing, a significant amount of oil still remains in the press cake. The aim of this study was to investigate the possible use of PSOPC flour as a substitute for wheat flour in biscuit production and, consequently, for reducing shortening usage. Biscuits have been produced from composite blends of plain white flour and PSOPC flour in ratios 100:0, 80:20, 60:40 and 40:60, respectively. Shortening addition was gradually reduced depending on the PSOPC flour addition. Biscuit baking quality was determined by width, thickness, spread factor, volume and textural properties. Computer vision was used to evaluate biscuit colour, and sensory evaluation was conducted for colour, taste, texture and overall acceptance. Results showed that PSOPC flour decreased biscuit diameter, height and volume and also caused a softer texture of biscuit. PSOPC flour contributed to the greenish colour of biscuits and the pleasant taste of roasted pumpkin seed. PSOPC flour can be successfully used as a functional and nutritionally valuable substitute for wheat flour and shortening, even in quantities up to 60%, without significant deterioration of the technological quality of biscuits.

Indexing p. 1  Editorial Bord p. 1  Guide for Authors p. 3  Manuscript preparation p. 5

Kosović I., Jukić M., Jozinović A., Ačkar Đ., Koceva Komlenić D. (2016): Influence of chestnut flour addition on quality characteristics of pasta made on extruder and minipress. Czech J. Food Sci., 34: 166-172.Durum semolina was replaced with 10, 15, and 20% of chestnut flour. Pasta was produced on a single screw extruder with the temperature profile of 80/90/90°C and on a laboratory minipress. Pasta samples were dried at room temperature and physical and sensory properties were determined. Generally, the chestnut flour addition to durum wheat pasta decreased optimum cooking time, hardness, cohesiveness, and chewiness, but increased cooking losses and pasta adhesiveness. Samples made on an extruder showed shorter optimum cooking times in relation to samples made on a minipress. Absorbed water was decreased with chestnut flour addition. Pasta made on an extruder showed a higher sensory score in comparison with pasta made on a minipress. The addition of chestnut flour influenced the colour of the samples. Samples made on an extruder showed darker colour in dried and cooked pasta samples in relation to minipress samples. In dried pasta samples, the extruder gave yellower samples in relation to the minipress, while in cooked pasta samples it was reversed. Overall, the extruder gave higher-quality pasta compared to the minipress.

Indexing p. 1  Editorial Bord p. 1  Guide for Authors p. 3  Manuscript preparation p. 5

Beers are differentiated mainly according to their visual appearance and their fermentation process. The main quality characteristics of beer are appearance, aroma, flavor, and mouthfeel. Important visual attributes of beer are foam appearance (volume and persistence), as well as the color and clarity. To replace manual inspection, automatic, objective, rapid and repeatable external quality inspection systems, such as computer vision, are becoming very important and necessary. Computer vision is a non-contact optical technique, suitable for the non-destructive evaluation of the food product quality. Currently, the main application of computer vision occurs in automated inspection and measurement, allowing manufacturers to keep control of product quality. This paper presents an overview of the applications and the latest achievements of the computer vision methods in determining the external quality attributes of beer.