Starch Characterisation ofAraucaria angustifolia andAraucaria araucana Seeds

Nonconventional Hydrocolloids’ Technological and Functional Potential for Food Applications

This review aims to study the alternatives to conventional industrial starches, describing uncommon sources along with their technological characteristics, processing, and performance on food products. Minor components remaining after extraction play an important role in starch performance despite their low percentage, as happens with tuber starches, where minerals may affect gelatinization. This feature can be leveraged in favor of the different needs of the food industry, with diversified applications in the market being considered in the manufacture of both plant and animal-based products with different sensory attributes. Hydrocolloids, different from starch, may also modify the technological outcome of the amylaceous fraction; therefore, combinations should be considered, as advantages and disadvantages linked to biological origin, consumer perception, or technological performance may arise. Among water-based system modifiers, starches and nonstarch hydrocolloids are particularly interesting, as their use reaches millions of sales in a multiplicity of specialties, including nonfood businesses, and could promote a diversified scheme that may address current monocrop production drawbacks for the future sustainability of the food system.

Assessment of the use of cooked Araucaria angustifolia seed coats extract as food for brine shrimp

The use of vegetable waste and its screening for potential cytotoxicity is of utmost importance to ensure its safe use in the feed industry for fish and other animals. We evaluated aqueous and ethanolic extracts of cooked Araucaria angustifolia seed coats. The Stiasny index for the aqueous and ethanolic extracts was 2.87% ± 0.03% and 60.53% ± 4.79%, respectively. Condensed tannins were 11-fold higher in the ethanolic extract than the aqueous extract. The flavonoid and polyphenol contents were 1.7- and 1.8-fold higher in the ethanolic extract than in the aqueous extract, respectively. The 36 h EC₅₀ for brine shrimp hatchability was 300.32 µg/mL for the aqueous extract, and 76.60 µg/mL for the ethanolic extract. The 24 h LC₅₀ was 1405.96 µg/mL for the aqueous extract, and it was 356.32 µg/mL for the ethanolic extract. The aqueous extract was nontoxic to A. salina nauplii, and therefore, it can be used as a possible food additive in fish feed. The results also demonstrated that the different solvents used in the extraction affected the yield and the total phenolic, total flavonoid, and condensed tannin content. Further in vivo and cell line cytotoxicity testing is recommended to substantiate these findings.

Physicochemical Properties of A- and B-type Granules of Wheat Starch and Effects on the Quality of Wheat-Based Noodle

This work fractionated native wheat starches into A- and B-type granules fractions to accurately assess granules physicochemical properties and effects on water distribution, storage modulus (E′) and loss modulus (E″) of two type noodles with A- and B-type granules. Pasting viscosity and starch crystallization of A- and B-type granules were determined by Rapid Visco Analyzer (RVA) and X-ray diffraction (XRD) respectively. The noodles were prepared from wheat flour, which 20 % was replaced with the A or B starch fractions, respectively. The water distribution and dynamic mechanical properties of noodles were characterized through Low-field Nuclear Magnetic Resonance (LF-NMR) and Dynamic Mechanical Analysis (DMA). The results demonstrated that A- and B-type granules almost had a round shape with smooth surface. The crystal models of A- and B-type granules were the same but the relative crystallinity were different. A-type granules contained higher starch content, higher ratio between amylose and amylopectin and less damaged starch than B-type granules. B-type granules easily aggregated into clump in deionized water. A- and B-type granules were different in swelling properties and pasting viscosity under the same conditions. A-type granules possessed lower swelling power and water-binding capacity, higher solubility and pasting viscosity than B-type granules. A-noodles (relative to B-noodles) had higher ratio of immobilized water, E′ and E″.

Effect of the alkaline treatment on the ultrastructure of C-type starch granules

The effect of alkaline treatment on the ultrastructure of C-type starch granules was investigated during the alkaline extraction of Araucaria angustifolia (pinhao) starch. The efficiency in protein removal was evaluated using intrinsic fluorescence and Kjeldahl's method. In parallel, morphological changes of starch granules were observed using scanning electron microscopy and atomic force microscopy. The starch crystallinity was monitored by wide-angle X-ray scattering and the lamellar structure was studied by small-angle X-ray scattering (SAXS). The paracrystalline model was employed to interpret the SAXS curves. It was found that the granular organization was significantly altered when alkaline solutions were used during the extraction. A partial degradation of B-type allomorph of starch and a significant compression of semicrystalline growth rings were observed.