Barley By-products Research Articles

Valorization of Agricultural Side-Streams for the Rearing of Larvae of the Lesser Mealworm, Alphitobius diaperinus (Panzer)

During the last decade, insects have shown up as a promising answer to the increasing animal protein demand for a continuously growing human population. A wide spectrum of substrates of plant origin can be currently used as insect feed; the sustainability of insect rearing though greatly increases when organic side-streams and wastes are valorized and upcycled through their bioconversion with insects. Additionally, the exploitation of low-cost organic residues as insect feed can also significantly suppress the rearing cost and, consequently, the price of the insect meal. In this context, the aim of our work was to evaluate organic side-streams, generated through several agro-industrial processes, as feeding substrates for the larvae of the lesser mealworm, Alphitobius diaperinus. In a laboratory trial, eleven agricultural side-streams were provided to larvae singly to assess their potential to support complete larval development, whereas in the second trial, larvae were fed two groups of isoproteinic diets consisting of the side-streams that performed well in the first trial. Our results showed the suitability of several agricultural side-streams as feed for A. diaperinus larvae, e.g., barley by-products (classes I and II), sunflower meal, cotton cake and oat sidestream, which, when fed singly, efficiently supported larval growth, resulting in high survival rates and final larval weights, comparable to the control. Similarly, several of the side-streams-based diets tested were shown to be suitable for A. diaperinus rearing. These results aim to contribute to the utilization of agricultural side-streams singly or in composed diets for the rearing of A. diaperinus larvae.

OPPORTUNITIES TO INCREASE SOIL PRODUCTIVITY OF DEGRADED AGRICULTURAL LAND USING NON-TRADITIONAL ORGANIC

А vegetation experiment was conducted on alluvial medium-loamy soil using effluent from cattle manure and organomineral fertilizer based on it as non-traditional meliorants. The positive effect of the studied meliorants on the yield of the main and by-products of barley was experimentally established. The largest increase in grain yield was obtained when they were applied at a dose of 20 t/ha (8.8 and 14.4 g/vessel, respectively).

Effects of Blends of Low-Protein Winter Wheat Flour and Barley Byproducts on Quality Changes in Noodles

The physicochemical characteristics of fresh noodles made with blends of low-protein wheat flour and barley byproduct (BBP, 250 μm) were investigated. The crude protein contents (PC) of flour from Goso and Backjoong cultivars were 7.91% and 7.67%, respectively. PC and β-glucan contents from the BBP were 14.10% and 3.11%, respectively, which were higher than those in wheat flour. The water-holding capacity (WHC) of various blends was increased as a function of BBP but not gluten contents. Goso flour had the highest starch content (78.68%), with peak and final viscosities of 3,099 and 3,563 cp, respectively. Peak and final viscosities, trough, breakdown, and setback of the blends were decreased with the addition of BBP. Noodles made with Backjoong had the highest thickness score, while the hardness of noodles made with blends of Goso or Backjoong and 20% BBP were similar to those made from wheat flour only. The WHC of the samples was strongly correlated with PC, crude fiber, and β-glucan. The PC was not correlated with final viscosity, setback, thickness, hardness, gumminess, or chewiness.

Isolation and characterization of cellulose nanocrystals from industrial by-products of Agave tequilana and barley

Agave tequilana and barley by-products from the Mexican food industry were characterized to determine their chemical composition and morphology by scanning electron microscopy (SEM). Cellulose was then extracted by carrying out alkali and bleaching treatments and cellulose nanocrystals (CNC) were isolated by an acid hydrolysis. Structural analyses and thermal stability of the isolated CNC were studied by X-ray diffraction (XRD) and thermogravimetric analysis (TGA), respectively. atomic force microscopy (AFM) and diffusion light scattering (DLS) were used to investigate the morphology of the CNC. The results indicate that hemicellulose and lignin were removed from the extracted cellulose. The isolated CNC from bagasse were found to be longer than those from microcrystalline cellulose (MCC), with a length of 322±112 and 329±123nm for A. tequilana and barley CNC, respectively, compared to 218±56nm for CNC from MCC. The degradation temperature of A. tequilana and barley CNC was at least 30°C higher than CNC from MCC. These values are promising for the value of by-products for the isolation of CNC and their use in reinforced-polymer manufacturing.

Development of Functional Spaghetti Enriched in Bioactive Compounds Using Barley Coarse Fraction Obtained by Air Classification

Barley byproducts obtained by air classification have been used to produce a different barley functional spaghetti, which were compared to different commercial whole semolina samples. Total, insoluble, and soluble fiber and β-glucan contents of the barley spaghetti were found to be greater than those of commercial samples. Furthermore, it was proved that barley spaghetti reached the FDA requirements, which could allow these pastas to deserve the health claims "good source of dietary fiber" and "may reduce the risk of heart disease". When the barley coarse fraction was used, a flavan-3-ols enrichment and an increase of antioxidant activity were reported, while commercial samples showed the absence of flavan-3-ols and a higher presence of phenolic acids and tannins. Whole semolina commercial spaghetti had a significantly higher content of phenolic acids than semolina spaghetti samples. Besides, it was observed that when vital gluten was added to the spaghetti formulation, phenolic compounds were blocked in the gluten network and were partially released during the cooking process.

Biological activity of barley (Hordeum vulgare L.) and barley by-product extracts

Barley and barley by-product extracts, waxy and non waxy genetic type, were prepared and investigated for its biological activity. The color, total phenolic contents, antioxidative activity, tyrosinase inhibition activity, xanthin oxidase inhibition activity, and angiotensin converting enzyme inhibition activity of the samples were measured. Hunter L* values of the by-products extract had higher than that of the whole and milled barley extracts. The contents of total phenolic compounds of the barley byproducts, waxy and non waxy type, were 18.60 and 17.92 mg/g of sample, respectively. The 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity of waxy type whole, milled barely, and barley by-product extracts were 65.43, 30.84, and 54.62%, respectively. Inhibition rates (%) of the mushroom tyrosinase of the waxy type whole barley, milled barley, and barley by-products extracts powder were 26.76, 16.30, and 33.60% at 250 ppm, respectively. The samples showed an inhibition effect of xanthin oxidase and angiotensin converting enzyme.

Mycological survey and ochratoxin A natural contamination of swine feedstuffs in Rio de Janeiro State, Brazil

Mycotoxin contamination of animal feeds represents a hazard to human and animal health due to potential transmission to meat and milk. Barley by-products are alternative feeding supplies for animal production. The aims of this assay were to study the mycobiota of feedstuffs and finished swine feed, to determine the ability of Aspergillus and Penicillium isolates to produce ochratoxin A (OTA) and to evaluate OTA occurrence in these substrates. Corn, brewers' grains and finished swine feed samples were collected from different factories. Fungal counts were higher than 2.8 × 10 4 CFU g −1. Fusarium, Aspergillus and Penicillium genera were isolated at high levels. A 23.7% of the isolates produced 9–116 μg kg −1 of OTA in vitro. Corn samples (44%) were contaminated with 42–224 μg kg −1 of OTA. Finished feed (31%) and brewers' grains samples (13%) were contaminated with 36–120 μg kg −1 and 28–139 μg kg −1 of OTA, respectively. This is the first scientific report on contamination by OTA-producer molds and OTA in swine feedstuffs from Brazil. The presence of OTA in raw materials and finished feed requires periodic monitoring to prevent mycotoxicoses in animal production, reduce economic losses and minimize hazards to human health.

Neurological disorder in dairy cattle associated with consumption of beer residues contaminated with Aspergillus clavatus.

A neurological syndrome in dairy cattle associated with consumption of moldy beer residues is described. The disease occurred on 1 farm in late June 2001, during winter. Six heifers and 1 cow out of 45 cattle were affected during a 3-week period. The affected animals died spontaneously or were euthanized approximately 2-14 days after the onset of clinical signs. The clinical signs were characterized by flaccid paralysis and gait abnormalities. Clinical signs were more pronounced after exercise and included stiff and unsteady gait, knuckling at the fetlocks of the hind limbs, frequent falling, inability to rise, muscular tremors, especially of the head and the hindquarters, and drooling. Main necropsy findings included degenerative and necrotic changes of the larger medial muscle groups of the hindquarters, i.e., adductor, pectineus, quadriceps femoris, rectus femuris, sartorius, semimembranosus, semitendinosus, and vastus medialis, and of the forequarters, including pectoralis descendens, pectoralis ascendens, and transversus pectoralis. The main histologic findings consisted of degenerative and necrotic neuronal changes (chromatolysis) of varying severity and extent affecting selected nuclei of the brainstem and neurons of the ventral horns of the spinal cord. Similar microscopic lesions were observed in the neurons of the spinal cord of 1 experimental sheep force-fed for 35 days with 1 kg/day of the same batch of foodstuff that was originally fed to the cattle. Coarse white or gray lumps, interpreted as mycelia, were observed in the beer by-product. Aspergillus clavatus was the dominant fungus isolated. Deaths ceased after the consumption of beer residue was discontinued. Recovery from illness was observed in 1 animal. The diagnosis was based on epidemiological data, clinical signs, necropsy findings, histological lesions, dosing trial, and mycology. A similar condition caused by consumption of barley by-products, sprouted wheat, corn sprouts, and beetroot screenings contaminated with A. clavatus has been reported in cattle and sheep worldwide.