Triticale flour in bakery and rusk products.

This paper researches the properties of two triticale varieties and three selection lines developed in Bashkortostan. The organoleptic indicators were typical of a standard grain; all the samples had a high protein content level. Gluten weight ratio matched the grain genotype. The falling number of the studied samples was low. Hydrothermal processing modes for triticale grain before grinding were optimized. The studied varieties and lines were found to yield 65.15%-70.18% of the flour. The conducted polynomial two-factor regression analysis proved that the flour yield factor is the grain softening period lasting 6 h. The dough deformation energy of the obtained flour samples was 67-129 units, the falling number 104-155 s indicates the low baking properties of the flour, thereby it was suggested to make brittle and crisp bakery products as crispbread and breadsticks. A breadstick formula with 60% wheat flour replaced with triticale flour was developed. The number of spore Rope bacteria increased slightly during the shelf life but did not exceed the permissible values. There have been developed formulas and methods to make crispbreads for producing crackers with triticale bran of 40% have been developed.

Application of ultrasound for enhancing fermentation rates in brewing technology.

BACKGROUND: There is much promise in technologies which may speed up time-consuming processes such as preparing seed yeast, primary fermentation and improving beer quality in the brewing industry. This study focuses on the activating and disintegrative effect of ultrasound with a 44 kHz frequency and a 1.0 W/cm2 intensity on brewer's yeast. METHODS: This study established that ten-minute ultrasonic treatment of yeast is sufficient to reach the stimulating effect. Further ultrasonic treatment is irrelevant since the percentage of dead cells in the yeast suspension exceeds the permissible levels (more than 10%). The experiment showed that two-minute ultrasonic treatment improved the physiological activity of seed yeast and shortened the time for producing seed yeast by 12 hours. Ultrasonic disintegration allowed a yeast extract to be obtained from the brewer's spent yeast. Ultrasound was applied to the yeast suspension for 19 minutes. RESULTS: The obtained yeast extract was used for additional nutrition in preparing seed yeast. It was found that the added yeast extract (2% of the total volume) shortened the time for preparing seed yeast by 6 hours due to the improved physiological state of the yeast. At the final stage, two-minute ultrasonic treatment and yeast extract (2% of the total volume) were used to activate the seed yeast. CONCLUSIONS: The seed yeast activation shortened the time for preparing seed yeast by 18 hours, and for the primary fermentation by 24 hours, while also improving the quality of the beer.

Wax esters of different compositions produced via engineering of leaf chloroplast metabolism in Nicotiana benthamiana.

In a future bio-based economy, renewable sources for lipid compounds at attractive cost are needed for applications where today petrochemical derivatives are dominating. Wax esters and fatty alcohols provide diverse industrial uses, such as in lubricant and surfactant production. In this study, chloroplast metabolism was engineered to divert intermediates from de novo fatty acid biosynthesis to wax ester synthesis. To accomplish this, chloroplast targeted fatty acyl reductases (FAR) and wax ester synthases (WS) were transiently expressed in Nicotiana benthamiana leaves. Wax esters of different qualities and quantities were produced providing insights to the properties and interaction of the individual enzymes used. In particular, a phytyl ester synthase was found to be a premium candidate for medium chain wax ester synthesis. Catalytic activities of FAR and WS were also expressed as a fusion protein and determined functionally equivalent to the expression of individual enzymes for wax ester synthesis in chloroplasts.

Mobilization of lipid reserves during germination of oat (Avena sativa L.), a cereal rich in endosperm oil.

Since the cereal endosperm is a dead tissue in the mature grain, beta-oxidation is not possible there. This raises the question about the use of the endosperm oil in cereal grains during germination. In this study, mobilization of lipids in different tissues of germinating oat grains was analysed using thin-layer and gas chromatography. The data imply that the oat endosperm oil [triacylglycerol (TAG)] is not a dead-end product as it was absorbed by the scutellum, either as free fatty acids (FFAs) released from TAG or as intact TAG immediately degraded to FFAs. These data were supported by light and transmission electron microscopy (LM and TEM) studies where close contact between endosperm lipid droplets and the scutellum was observed. The appearance of the fused oil in the oat endosperm changed into oil droplets during germination in areas close to the aleurone and the scutellar epithelium. However, according to the data obtained by TEM these oil droplets are unlikely to be oil bodies surrounded by oleosins. Accumulation of FFA pools in the embryo suggested further transport of FFAs from the scutellum. Noticeably high levels of TAG were also accumulated in the embryo but were not synthesized by re-esterification from imported FFAs. Comparison between two oat cultivars with different amounts of oil and starch in the endosperm suggests that an increased oil to starch ratio in oat grains does not significantly impact the germination process.

The distribution of oil in the oat grain.

High-lipid oat is a potential oil crop. Chemical and microscopical analyses have shown that the major part of the grain lipids are stored in the endosperm. While oil bodies are intact in the aleurone layer, scutellum and embryo, they have less associated proteins (oleosins) and undergo fusion in the starchy endosperm. In this report, we document the distribution of lipids in the endosperm microscopically. Underneath the aleurone layer, lipids are most abundant in the subaleurone cells and in the endosperm cells in the vicinity of the scutellum and embryo. Thus the major areas of oil storage are close to the living tissues of the grain, the sites of enzyme production in connection with germination and mobilization. The documentation of cellular structural changes, and implication of the fused state of oil bodies, during germination, remains to be elucidated.

Analysis of oil composition in cultivars and wild species of oat (Avena sp.).

Oil quality and content were analyzed in 33 accessions from 13 wild species and 10 accessions of cultivated oat. Wild oat species tended to have higher oil and 18:1 fatty acid (FA) contents and lower amounts of 18:2 and 18:3 FAs as compared to cultivated oats. In addition to common FAs, minor amounts of several hydroxy and epoxy FAs were also present in the oat oil and mainly confined to specific lipid classes. These unusual FAs included the previously reported 15-hydroxy 18:2 (Delta9,12) (avenoleic acid) mostly found among polar lipids and a novel 7-hydroxyhexadecanoic acid located to 1,2-diacylglycerol. The present study highlights the potential of making use of the existing germplasm, consisting of wild oat species, in breeding programs for achieving new oat varieties that produce a range of oils with different FA compositions as well as having high oil contents. However, in one matter, oats apparently lack genetic diversity and that is for oil qualities that are highly enriched in the omega 3 (omega-3) FA 18:3. Consequently, developing oat cultivars with highly unsaturated oils will need involvement of other techniques such as biotechnology.

Fusion of oil bodies in endosperm of oat grains.

Few microscopical studies have been made on lipid storage in oat grains, with variable results as to the extent of lipid accumulation in the starchy endosperm. Grains of medium- and high-lipid oat (Avena sativa L.) were studied at two developmental stages and at maturity, by light microscopy using different staining methods, and by scanning and transmission electron microscopy. Discrete oil bodies occurred in the aleurone layer, scutellum and embryo. In contrast, oil bodies in the starchy endosperm often had diffuse boundaries and fused with each other and with protein vacuoles during grain development, forming a continuous oil matrix between the protein and starch components. The different microscopical methods were confirmative to each other regarding the coalescence of oil bodies, a phenomenon probably correlated with the reduced amount of oil-body associated proteins in the endosperm. This was supported experimentally by SDS-PAGE separation of oil-body proteins and immunoblotting and immunolocalization with antibodies against a 16 kD oil-body protein. Much more oil-body proteins per amount of oil occurred in the embryo and scutellum than in the endosperm. Immunolocalization of 14 and 16 kD oil-body associated proteins on sectioned grains resulted in more heavy labeling of the embryo, scutellum and aleurone layer than the rest of the endosperm. Observations on the appearance of oil bodies at an early stage of development pertain to the prevailing hypotheses of oil-body biogenesis.