Amaranth functional cookies exert potential antithrombotic and antihypertensive activities

In this study, amaranth flour was used as an ingredient to prepare gluten-free cookies. The production process and attributes of amaranth cookies were characterised, and the potential use of amaranth flour as a functional ingredient was analysed. Cookies exhibited a non-uniform reddish brown colour and a cookie factor ratio of 4.5 ± 0.6. Storage studies indicated that after 3 weeks at room temperature cookies presented slight variations in the texture. Simulated gastrointestinal digestion of this product was able to release peptides capable of exerting potential antithrombotic and antihypertensive activities, IC₅₀ values of 0.22 ± 0.04 and 0.23 ± 0.03 mg mL⁻¹ protein, respectively. This work demonstrates for the first time that food made with amaranth flour exerts potential antithrombotic and antihypertensive activity. In conclusion, these amaranth cookies could be an alternative way of incorporating potentially health beneficial products for people who choose a conscious diet, including coeliac or vegan consumers.     

Some compositional properties of seeds and oils of eightAmaranthus species

Grain of 21Amaranthus accessions (eight species) was analyzed for crude fat, fatty acid profiles (FAP), and vitamin E (tocopherols and tocotrienols). Contents of (1→3), (1→4) β-glucan were determined in 12 accessions (four species), and trypsin inhibitor activity (TIA) in 20 accessions (six species). FAP and vitamin E profiles were compared to those of barley, buckwheat, corn, lupin, oat, and wheat oils. Crude fat content ranged from 5.2 to 7.7%, and of the oils examined, amaranth oil was most similar in FAP to corn and buckwheat oils. Amaranth was higher than all but wheat and lupin in tocopherol content but was virtually devoid of tocotrienols, which have been shown to have hypocholesterolemic activity. Amaranth grain did not contain (1→3), (1→4) β-glucans and was low in trypsin inhibitor activity (≤4.3 trypsin units inhibited/mg). Any hypocholesterolemic effects of dietary amaranth are apparently due to substances other than (1→3), (1→4) β-glucans or tocotrienols.     

Weissella cibaria short-fermented liquid sourdoughs based on quinoa or amaranth flours as fat replacer in focaccia bread formulation

Production of the traditional Italian Focaccia bread (FcBread) requires reformulation to meet the new rules for healthier foods. We tested the applicability of a short-fermented (15 h) liquid sourdough (LS) (dough yield, DY, 250), obtained using quinoa (Q) or amaranth (Am) flour fermented with a Weissella cibaria strain (C43-11) producing exopolysaccharides (EPS) as fat replacer in yeast-leavened FcBread. The LSs were applied during the FcBread-making process at industrial pilot plant, reducing the added fat amount by 20% (FcBread-QLS and FcBread-AmLS) and products were compared with reference samples not containing EPS. All the products were analysed for physico-chemical properties (pH, TTA, organic acids, protein content and profile, instrumental colour), textural properties, sensory quality and glycemic index. The application of both pseudo-cereal-based W. cibaria LSs in FcBread allowed obtaining products with a reduced amount of fat, increased protein amount, mainly due to the albumin and glutenin/glutelin fractions, reduced glycemic index, improved texture and preserved in the traditional sensory profile of ‘focaccia’.     

Relationship between physicochemical and functional properties of amaranth (Amaranthus hypochondriacus) protein isolates

Protein isolates from six amaranth lines/cultivars (APIs) were evaluated to study their physicochemical (hunter colour, protein content and zeta potential), structural (thermal and conformational) and functional (emulsification, foaming, water and fat absorption) properties. APIs had protein content, whiteness index and gel temperature in range of 79.4–85.4%, 41.17–54.26 and 87.8–91.8 °C, respectively. The Fourier‐transform infrared spectra of APIs revealed α‐helix, β‐sheets and random coil conformations in the secondary structure. APIs with higher relative proportion of β‐sheets had higher Differential Scanning Calorimeter denaturation temperature and gel temperature. Minimum protein solubility (PS) was observed at pH 5.0, indicating isoelectric point (pI) of amaranth proteins. The PS, emulsifying activity index (EAI), emulsifying stability index (ESI), foaming capacity (FC) and foam stability (FS) of APIs at neutral pH were related to their zeta potential (ζ). The emulsifying and foaming properties were also determined at different pHs (between 2.0 and 9.0). The EAI‐pH profile of APIs confirmed close relationship between the emulsifying ability and PS.     

Bench-scale processing of amaranth seed for oil

Amaranth seed (Amaranthus hypochondriacus cv. K432) was processed to obtain oil, reported to be a promising source of squalene. The amaranth seed was ground using a stone mill, then separated into oil-rich embryonic tissue (or “bran”) and starchy perisperm. Amaranth bran was much more stable than rice bran when free fatty acid (FFA) content and peroxide value were monitored. Milling at a gap of 0.755 mm did not result in excessive damage to the starch in the perisperm fraction and yielded a bran fraction that contained more than three-fourths of the oil and a starchy fraction consisting of more than two-thirds of the seed weight. The bran particles were too fine for effective bench-scale extraction of the oil. Consequently the bran was extruded into collects prior to extraction. Two extrusion settings were evaluated regarding the rate of moisture injection, while the bran feed rates were constant. There was no significant difference in appearance or size between the two dried collets. Collets were extracted with hexane using an Armfield Extraction/Desolventizing Unit (Model FT 29, Armfield, Ltd., Hampshire, England). Oil recovery averaged 97.7 and 80.0%, respectively. Oil was extracted at high yield from the bran when the bran was extruded into collets. Oil can be obtained as a coproduct of amaranth starch by milling and separating the fractions of amaranth seed. Milling, extrusion, and extraction did not decrease significantly the squalene content in amaranth oil, but increased FFA content and peroxide value and changed tocopherol content of the oil.     

Comparison of properties of native and extruded amaranth (Amaranthus cruentus L. - BRS Alegria) flour

The aim of this study was to compare some of the properties of native and extruded amaranth flour obtained under mild and severe extrusion conditions. The chemical composition of the flours was similar. Flours obtained by both extrusion processes presented high solubility in water, low values of L∗ (luminosity) and an absence of endothermic peak on the DSC method. Water absorption, retrogradation tendency, final viscosity and the viscous behavior by rheology analysis were also studied. The results indicate that extruded flours have a good potential as an ingredient for food exposed to heat treatment at a high temperature and mechanical shear, for use in instant meal products. On the other hand, original flour properties are comparable to those of amaranth starch, which exhibits similarly high quality paste stability, low solubility in water, and elastic behavior, and could be used as a substitute for raw flour in a range of food formulas.     

籽粒苋在瘦肉型良种猪养殖中的应用

介绍了籽粒苋的种植技术、采收方法、喂猪方法和效果，并阐述了自己的一些经验和体会。     

Functional properties of protein preparations from amaranth seeds in model system

The gross chemical composition and functional properties (solubility, emulsifying and foaming properties) of different amaranth protein preparations were studied in model systems and were compared to those of casein and soy protein isolates. Preparations of alkaline-soluble total protein, albumin, globulin, and glutelin-like alkaline-soluble residual protein were produced from two different types of defatted amaranth meals by extraction and fractionation. Although similarity can be shown between protein patterns of legumes (including soy) and amaranth, the emulsifying and foaming properties of amaranth protein preparations are relatively poor in comparison to the reference proteins, except foaming properties of albumin preparations. Nevertheless, taking in mind that these properties depend on interactions with other food components and textural requirements of individual food products, the amaranth protein preparations may be treated as potential protein sources and food ingredients.     

Anthocyanins,total polyphenols and antioxidant activity in amaranth and quinoa seeds and sprouts during their growth

Total antioxidant capacity, total phenolic contents (TP) and anthocyanins contents (ANT) were determined in Amaranthus cruentus and Chenopodium quinoa seeds and sprouts. Antioxidant activity of the investigated seeds decreased in the following order: quinoa, amaranth v. Rawa, amaranth v. Aztek for FRAP and quinoa, amaranth v. Aztek, amaranth v. Rawa for both ABTS and DPPH. Sprouts activity depended on the length of their growth, and the peak values were reached on the fourth day in the case of amaranth and on the sixth day in the case of quinoa. The data obtained by the three methods showed significant correlation between TP content in seeds and sprouts. In sprouts grown in the daylight and in the darkness we observed some significant changes of TP, ANT and antioxidant activity. Amaranth and quinoa seeds and sprouts can be used in food, because it is a good source of ANT and TP with high antioxidant activity.