ABSTRACT
This study compared the physicochemical properties of edible insect oils from silkworm (Bombyx mori) pupa (SP), sago palm weevil (Rhynchophorus ferrugineus) larva (PW), and bamboo caterpillar (Omphisa fuscidentalis; BC) to oils from chicken skin (CK), beef back fat (BF), pork back fat (PF), salmon belly (SB), sea bass belly (BB), coconut (C), and peanut (P). The fatty acid profiles and thermal behaviors (crystallization and melting) of the extracted oils were evaluated. PW and BC oils had more saturated fatty acids (SFAs) than CK, PF, SB, BB, and P oils. SP oil had equivalent SFA content to CK and BB oils. Insect oils exhibited similar monounsaturated fatty acid concentrations in all samples, except C oils. PW and BC oils exhibited a higher content of palmitoleic acid than the other oils. SP oils contained polyunsaturated fatty acids similar to those in SB and BB oils, which were higher than those in PW, BC, CK, BF, and PF oils. SP oil also exhibited the highest concentration of α-linolenic acid (C18:3 n-3). Arachidonic acid (0.01-0.02 g/100 g) in all insect oils was lower level compared to CK, BF, PF, SB, and BB oils. SP oil (0.03 g/100 g) exhibited a slightly higher level of eicosapentaenoic acid compared to PW (0.01 g/100 g) and BC (0.01 g/100 g) oils. The insect oils were liquid at ambient temperature, solid below -15°C, and required less energy (â³Hm-max) for melting than other samples. This study indicated that insects, particularly SP, could serve as an alternative source of fat to meet its growing demand.
ABSTRACT
The quality characterization of different parts of male and female Ligor hybrid chickens was investigated and compared with those of commercial broiler. Genotypes, muscle types, and sex had effects on the composition, physicochemical, and textural properties of chicken samples. Ligor hybrid chicken contained higher percentages of protein, moisture, ash, and collagen content but lower fat content than those of commercial broiler (p < 0.05), except in the case of breast, where no significant difference in moisture and ash was observed (p ≥ 0.05). The pH in breast meat of both chickens was lower than that of thigh meat. The color (L*, a*, and b*) values of male and female chickens were not significantly different, except for the L* value of broiler chicken, which was higher in female chickens than in male chickens. Higher cooking loss and shear force were found in male Ligor hybrid chicken. A similar protein pattern was observed for the protein from the same muscle type, irrespective of sex and genotype tested. It was observed that Ligor hybrid chicken contained higher glutamic acid and aspartic acid than commercial broilers. Therefore, Ligor hybrid chicken is a promising new source of nutrition, which can be beneficial for consumers.
ABSTRACT
A low gel-forming ability is needed to be encountered using the dark-fleshed fish as a raw material. Optimal washing process can be a principled way of improving the gelling properties because washing is the most important step for surimi production. This study aimed to investigate the effect of ultrasonic-assisted washing (UAW) on the biochemical properties and gel-forming ability of frigate mackerel (Auxis thazard) surimi. Unwashed mince and conventional washing (CW) with 3-cycle of water (10 min per cycle) were compared to UAW for 5 and 10 min per cycle. UAW tended to improve the lipid removal, reduce the TCA-soluble peptide, and increase the surface hydrophobicity of surimi, but it had no influence on the Ca2+-ATPase activity, reactive sulfhydryl content, haem protein content, and lipid oxidation. UAW for 5 min per cycle rendered the surimi with the highest gel strength, whiteness, and water holding capacity as well as a regular aggregated network. With this method, the washing time can be reduced to 50% compared to the CW. Therefore, UAW for 5 min per cycle was an alternative approach for the production of mackerel surimi.
ABSTRACT
BACKGROUND: Clown featherback (Chitala ornata) skin, a by-product from the filleting process line, could serve as a good aquatic collagenous source. Nevertheless, the typical collagen extraction method is a time-consuming process providing a relatively low yield. Ultrasound had been reported to be an alternative technique for enhancing the extraction efficiency of several compounds, although the harsh conditions of ultrasound could affect their physicochemical and molecular characteristics. Thus, the application of ultrasonication under appropriate conditions could comprise a promising means for improving the extraction efficiency of collagen from clown featherback skin. RESULTS: Ultrasonication using different amplitudes (20-80%) and times (10-30 min) was implemented during extraction. An ultrasound-assisted process (UAP) was able to increase the yield of collagen (P Ë 0.05) and could also result in a collagen purity decrease as evaluated by hydroxyproline content. There was no dramatic change in the solubility of resulting collagens. UAP induced protein degradation, particularly with an increasing amplitude and time, where slight changes in the isoelectric point value of collagen were observed. UAP had no adverse effect on molecular structure, where a triple-helical structure was still retained when an 80% amplitude was employed for 10 min (UAP-80/10-C). The amino acid composition of UAP-80/10-C reconfirmed the unique characteristic of collagen containing imino acid. CONCLUSION: An UAP under appropriate conditions could be used to improve the extraction yield with minimal effects on the molecular integrity of the resulting collagen. In addition, fish skin waste from the cutting process line, particularly clown featherback skin, could be exploited as a value-added product, comprising fish skin collagen. © 2020 Society of Chemical Industry.
