The Impact of Drying Method on the Functional and Antioxidant Properties of Whitecheek Shark(Carcharhinus dussumieri) Protein Hydrolysates

Exploitation of bones-rich poultry by-products to produce protein hydrolysates: optimization of hydrolysis parameters and chemical characterization

A significant quantity of bone-rich poultry by-products must be disposed of by poultry processors. These products still contain a significant amount of nutritionally valuable animal proteins. In the present work, a hydrolysis protocol was optimized to recover the protein fraction of bone-rich poultry by-products while simultaneously minimizing the amount of water required for hydrolysis (thus reducing drying costs) and recycling the hydrolytic broth up to 3 times, to reduce the cost of the proteolytic enzyme. The final hydrolysis conditions involved the use of (protease from B. licheniformis, ≥2.4 U/g; 0.5 V/w of raw material) and a hydrolysis time of 2 h at 65°C. The protein hydrolysate obtained has a high protein content (79-86%), a good amino acid profile (chemical amino acid score equal to 0.7-0.8) and good gastric digestibility (about 30% of peptide bonds are already hydrolyzed before digestion). This supports its use as an ingredient in food, pet food or animal feed formulations.

Effects of cluster dextrin encapsulation on the properties and antioxidant stability of fractionated Riceberry protein hydrolysate powder prepared by bromelain

In this work, the biological properties of fractionated Riceberry bran protein hydrolysate obtained by ultrafiltration (URBPH) were evaluated and the possibility of using cluster dextrin to produce hydrolysate powder by spray-drying was investigated. Fractionation into peptides < 3 kDa was observed to improve antioxidant activity. URBPH < 3 kDa was then freeze-dried (FD-URBPH) and spray-dried (SD-URBPH) at different inlet air temperatures of 100-160 °C. The water solubility and antioxidant activity of FD-URBPH were higher than those of SD-URBPH. Nevertheless, encapsulation of hydrolysate with 10% cluster dextrin and an inlet temperature of 120 °C was also successful in maintaining protein qualities, which showed high 2,2'-azino-bis 3-ethylbenzthiazoline-6-sulfonic (ABTS•+) scavenging activity (89.14%) and water solubility index (92.49%) and low water activity (aw = 0.53). Moreover, encapsulation preserved the antioxidant activity of peptides during gastrointestinal digestion better than the free form. URBPH and its spray-dried microcapsules could be used as bioactive ingredients in functional drinks or foods.

Extraction, optimization, and functional quality evaluation of carotenoproteins from shrimp processing side streams through enzymatic process

The study aimed to develop an effective and eco-friendly enzymatic process to extract carotenoproteins from shrimp waste. The optimization of enzymatic hydrolysis conditions to maximize the degree of deproteinization (DDP) of carotenoprotein from shrimp head waste (SHW) and shrimp shell waste (SSW) was conducted separately using the Box-Behnken design of response surface methodology (RSM). To achieve a maximum DDP of 92.32% for SSW and 96.72% for SHW, the optimal hydrolysis conditions were determined as follows: temperature (SSW: 53.13 °C; SHW: 45.90 °C), pH (SSW: 7.13; SHW: 6.78), time (SSW: 90 min; SHW: 61.18 min), and enzyme/substrate ratio (SSW: 2 g/100 g; SHW: 1.18 g/100 g). The carotenoprotein effluent obtained was subjected to spray drying and subsequently assessed for color, nutritional, and functional characteristics. The carotenoprotein from shrimp shell (CpSS) contained a higher essential amino acid score than carotenoprotein from shrimp head (CpSH). CpSS had a higher whiteness index of 82.05, while CpSH had 64.04. Both CpSS and CpSH showed good functional properties viz solubility, emulsion, and foaming properties. The maximum solubility of CpSH and CpSS was determined to be 92.94% and 96.48% at pH 10.0, respectively. The highest emulsion capacity (CpSH: 81.33%, CpSS: 70.13%) and stability (CpSH: 57.06%, CpSS: 63.05%) were observed at 3% carotenoprotein concentration. Similarly, the highest values of foaming capacity (CpSH: 27.66%, CpSS: 105.5%) and stability (CpSH: 23.83%, CpSS: 105.33%) were also found at the same 3% carotenoprotein concentration. In conclusion, the carotenoproteins obtained from shrimp waste showed favorable attributes in terms of color, amino acid composition, and functional properties. These findings strongly suggest the potential applicability of CpSS and CpSH as valuable resources in various domains. CpSS, with its higher whiteness index, greater amino acid content, and superior functional characteristics, may find suitability as functional ingredients in human food products. Conversely, CpSH could be considered for incorporation into animal feed formulations.

Effects of Spray Drying and Freeze Drying on Physicochemical Properties, Antioxidant and ACE Inhibitory Activities of Bighead Carp (Aristichthys nobilis) Skin Hydrolysates

The physicochemical, structural properties, antioxidant, and angiotensin I-converting enzyme (ACE) inhibitory activities of fish skin protein hydrolysate (SPH) that were freeze-dried (SPH-FD) and spray-dried (SPH-SD) were investigated. SPH-SD showed abundant volatile compounds, higher DPPH radical scavenging activity and ferrous iron chelating activity than SPH-FD, while the ABTS radical scavenging activity and ACE inhibitory activity were not influenced by the drying method. Amino acid compositions showed a higher proportion of proline and hydroxyproline residues in SPH-FD. The major molecular weights were both distributed below 1000 Da. SPH-SD had spherical structures, while SPH-FD had glass shard-like structures. The results indicated that the drying method could affect the physicochemical properties of hydrolysates, and SPH-SD showed potential prospects in developing functional fortified foods.

Effects of freeze-drying and spray-drying on the physical and chemical properties of Perinereis aibuhitensis hydrolysates: Sensory characteristics and antioxidant activities

This work was to investigate the impact of drying on the physical, chemical stability and character properties of P. aibuhitensis hydrolysate. Properties including amino acid composition, color stability, molecular weight distribution, powder morphology, etc. were compared between the freeze drying powder (FD) and spray drying powder (SD). They were fractionated with ultra filtration in antioxidant activities test. FD and SD contained amounts of amino acids and umami amino acids. SD exhibited the higher lightness and whiteness. SD had more compounds between 451 Da and 6511 Da. The surface morphology of FD was porous and flaky while SD was microsphere. SD had more volatile flavor substances and higher antioxidant activities on DPPH, hydroxyl, and superoxide radical-scavenging. In summary, results demonstrated that drying methods indeed affected the characteristics of hydrolysate, and the one prepared by spray drying method had the potential to be utilized for antioxidant food development and seafood seasoning.

Effect of Drying Techniques on the Physical, Functional, and Rheological Attributes of Isolated Sunflower Protein and Its Hydrolysate

The influence of freeze and convection (at 40 and 50 °C) drying on the physical, functional, and rheological attributes of sunflower protein (SP) and its hydrolysate (SPH) was investigated. Compared with convectively-dried samples, the lightness, turbidity, bulk density, and particle size values of the freeze-dried SP and SPH were substantially higher, but the browning index was lower (p < 0.05). Additionally, freeze-dried samples exhibited good solubility and foaming characteristics, whereas lower emulsion properties with the most pH values were observed. Furthermore, SPHs possessed higher solubility as well as foamability over SPs under varying pH values (2.0–10.0), whilst reduction in the emulsion activity index was clearly observed (p < 0.05). Convectively-dried powders exhibited greater viscosity and consistency coefficient; and significantly lower flow behavior index of dispersions, relative to the respective freeze-dried preparations, indicating that dehydration methods influenced the flow behavior of the investigated samples. From a molecular weight analysis, convectively-dried samples at various temperatures were characterized with high proportion of small-sized particles at ≤1 kDa fractions over the respective powders obtained by freeze drying. The observations made, thus, would benefit food processors and manufacturers in electing better dehydration technique based on the desired traits of SP and SPH powders for successful application in food product formulations.

Effects of different drying methods on the structures and functional properties of phosphorylated Antarctic krill protein

Antarctic krill protein (AKP) was extracted from Antarctic krill by an alkali dissolution-isoelectric precipitation method and then it was phosphorylated with sodium tripolyphosphate. The phosphorylated Antarctic krill protein (P-AKP) powder was obtained by spray-drying (SD), freeze-drying (FD), and hot-air drying (AD), and the effects of these drying methods on the structures and functional properties of proteins were investigated. The P-AKP powder dried by SD had the best sensory performance, and its particle size was much smaller than that of FD and AD. Scanning electron microscope displayed a uniform particle size of SD powder and the particles were uniformly dispersed. X-ray diffraction analysis showed a higher crystallinity of SD sample than AD and FD. Differential scanning calorimeter analysis revealed that SD sample had the best thermal stability and less protein denaturation (ΔH = 210.80 J/g), followed by FD (ΔH = 80.48 J/g) and AD (ΔH = 73.94 J/g; P < 0.05). Fourier transform infrared showed that SD sample contained more protein secondary structure. Compared with SD, the phosphorylated group-related chemical bonds in FD and AD samples were partially destroyed. SD sample had the highest protein solubility, oil absorption capacity, emulsifying, and foaming activities than FD and AD (P < 0.05). Although FD had the highest water absorption capacity, sample prepared with AD had the worst functional performance. Therefore, different drying methods used for preparation of the P-AKP can affect its physicochemical and associated functional properties, and SD could be an appropriate drying method for the industrial mass production of P-AKP powders with better functionalities. PRACTICAL APPLICATION: The optimal drying method for preparing the phosphorylated Antarctic krill protein (P-AKP) powder was proved to be spray-drying (SD), because the physicochemical and functional properties were better for P-AKP dried by SD than the other drying methods. Hence, SD was recommended for the industrial mass production of P-AKP powders with better functionalities. This research can provide theoretical guidance for the further processing and utilization of P-AKP, and offer technical reference for food processing and preservation.

Drying methods affect physicochemical and functional properties of quinoa protein isolate

Quinoa protein possesses great amino acid profiles and can be a potential food ingredient with broad applications. The objective of this study was to investigate the effect of different drying methods, namely freeze drying, spray drying, and vacuum drying on the functional and physicochemical properties of quinoa protein isolate, e.g., morphology, amino acid composition, SDS-PAGE profile, sulfhydryl/disulfide content, secondary structure, surface hydrophobicity, and thermal stability. The freeze-dried protein exhibited the highest emulsification capacity and stability and oil binding capacity, which was contributed to its higher surface hydrophobicity, while the spray-dried sample had the highest solubility and water absorption capacity at pH 7. Gels (8%) prepared with the freeze-dried protein had higher elastic and viscous modulus than that from others. The freeze-dried protein had the highest maximal denaturation temperature but lowest enthalpy, which may be attributed to its higher amount of random coil but lower percent of regular α-helix and β-sheet structures. Overall, quinoa protein isolate from different processing methods demonstrated distinct functional properties. This information will be useful to optimize quinoa protein production and benefit its applications.