In-vitro colonic fermentation of Kakadu plum (Terminalia ferdinandiana) fruit powder: Microbial biotransformation of phenolic compounds and cytotoxicity.

Kakadu plum (Terminalia ferdinandiana) (KP) is an indigenous fruit used as a functional ingredient in powdered form. Three KP doses (1, 2.5 and 5 g) were digested in a dynamic in vitro gut digestion model over 48 h. Faecal water digests from the colonic reactors were assessed for total soluble polyphenols (TSP), ferric reducing antioxidant power (FRAP), phenolic metabolites and short-chain fatty acids (SCFAs). Effects of digests on cell viability were tested against Caco-2 intestinal and HepG2 hepatic cells. All doses of KP fermentation produced castalagin, corilagin, chebulagic acid, chebulinic acid, and gallic acid. TSP and FRAP significantly increased in 5 g KP digests at 0 and 48 h of fermentation. SCFA concentrations significantly increased after 48 h. Cytotoxic effects of 2.5 and 5 g KP digests diminished significantly after 12 h. Overall, colonic fermentation increased antioxidant activity and polyphenolic metabolites of 5 g KP powder for 48 h.

In Vitro Antioxidant Activity, Bioaccessibility, and Thermal Stability of Encapsulated Strawberry Fruit (Fragaria × ananassa) Polyphenols.

Bioactive compounds in red fruits, such as strawberries, are vulnerable to digestion, and encapsulation has become an alternative for their protection. This study aims at encapsulating strawberry juice (SJ) by freeze-drying with pea protein and okra mucilage (SJPO), pea protein and psyllium mucilage (SJPP), and pea protein, psyllium mucilage, and okra mucilage (SJPPO) and investigating the in vitro release. The highest encapsulation efficiency was observed in capsule SJPPO (95.38%) and the lowest efficiency in SJPO (82.45%). Scanning electron microscopy revealed an amorphous glassy structure for the structure of the strawberry microcapsules, and X-ray diffraction confirmed that observation. However, X-ray diffraction further showed that SJPPO was crystalline, indicating a tighter crosslinking density than the other microcapsules. Fourier transform infrared spectroscopy showed peaks at 3390 and 1650 cm-1, confirming the presence of polyphenols and polysaccharides in the strawberry microcapsules. Thermal stability was higher for SJPPO, and the observed thermal transitions were due to the bonds formed between the polymers and polyphenols. Pelargonidin 3-glucoside, cyanidin 3-glucoside, cyanidin, delphinidin, malvidin 3-glucoside, ellagic acid, chlorogenic acid, catechin, and kaempferol were identified in the strawberry microcapsules. Digestion affected the compounds' content; the bioaccessibility for SJ was 39.26% and 45.43% for TPC and TAC, respectively. However, encapsulation improved the bioaccessibility of both TPC (SJPP, 51.54%; SJPO, 48.52%; and SJPPO, 54.39%) and TAC (SJPP, 61.08%; SJPO, 55.03%; and SJPPO, 71.93%). Thus, encapsulating pea protein isolate, psyllium mucilage, and okra mucilage is an effective method to facilitate targeted release and preserve the biological activities of fruits.

Quantitative determination of macro and micro elements and heavy metals accumulated in wild fruits analyzed by ICP-OES method.

The moisture amounts of wild fruits ranged from 51.07 (rosehip) to 88.49% (raspberry (yellow)). Wild strawberry generally contained the highest amounts of P, K and Ca. In addition, the highest Mg result was recorded in wild strawberry, fig and rosehip fruits. P and K amounts of wild edible fruits were recorded between 385 mg/kg (blackberry) and 2538 mg/kg (fig) to 6114 (medlar) and 18,613 mg/kg (wild strawberry), respectively. Depending on the fruit variety and type, the microelements found in the highest amounts were Zn, Cu, Mn and B. Fe resultss of fruits were reported at very low levels. Fe results of wild edible fruits changed between 0.21 (apple) and 1.32 mg/kg ((fig). Zn and Cu values of wild edible fruits were recorded between 1.39 (apple) and 16.4 mg/kg (fig) to 1.54 (apple) and 18.4 mg/kg (wild strawberry), respectively. Cu contents of raspberry (red), raspberry (yellow), blackberry, jujube and medlar fruits were found to be very close to each other. Arsenic (As) contents of wild fruits were recorded to be higher than those of other elements. In addition, some fruits have high heavy metal contents. The heavy metal found in the highest amounts in fruits was As, followed in descending order by Ali Ba, Se, Ni and Pb. The high As content of these fruits is likely due to the As content of the soil where the plants are grown and its contamination with As-rich industrial waste. While As contents of edible wild fruits are detected between 4.21 (rosehip) and 65.7 (wild strawberry), Al results of fruits were reported between 0.03 (rosehip) and 16.0 µg/g (mulberry (white)).

Exploring the impact of various cooking techniques on the physicochemical and quality characteristics of camel meat product.

OBJECTIVE: The objective of this study was to evaluate the effects of four different cooking techniques viz: boiling, grilling, microwave, and frying; on the physicochemical characteristics of camel meat. METHODS: Protein composition and their degradation as well as biochemical and textural changes of camel meat as influenced by cooking methods were investigated. RESULTS: The highest cooking loss (52.61%) was reported in microwaved samples while grilled samples showed the lowest cooking loss (44.98%). The microwaved samples showed the highest levels of lipid oxidation as measured by thiobarbituric acid reactive substances, while boiled samples showed the lowest levels (4.5 mg/kg). Protein solubility, total collagen, and soluble collagen content were highest in boiled samples. Boiled camel meat had lower hardness values compared to the other treated samples. Consequently, boiling was the more suitable cooking technique for producing camel meat with a reduced hardness value and lower lipid oxidation level. CONCLUSION: The camel meat industry and camel meat consumer can benefit from this research by improving their commercial viability and making consumers aware about the effects of cooking procedures on the quality of camel meat. The results of this study will be of significance to researchers and readers who are working on the processing and quality of camel meat.

Edible Halophytes with Functional Properties: In Vitro Protein Digestibility and Bioaccessibility and Intestinal Absorption of Minerals and Trace Elements from Australian Indigenous Halophytes.

Halophytes are considered emerging functional foods as they are high in protein, minerals, and trace elements, although studies investigating halophyte digestibility, bioaccessibility, and intestinal absorption are limited. Therefore, this study investigated the in vitro protein digestibility, bioaccessibility and intestinal absorption of minerals and trace elements in saltbush and samphire, two important Australian indigenous halophytes. The total amino acid contents of samphire and saltbush were 42.5 and 87.3 mg/g DW, and even though saltbush had a higher total protein content overall, the in vitro digestibility of samphire protein was higher than the saltbush protein. The in vitro bioaccessibility of Mg, Fe, and Zn was higher in freeze-dried halophyte powder compared to the halophyte test food, suggesting that the food matrix has a significant impact on mineral and trace element bioaccessibility. However, the samphire test food digesta had the highest intestinal Fe absorption rate, whereas the saltbush digesta exhibited the lowest (37.7 vs. 8.9 ng/mL ferritin). The present study provides crucial data about the digestive "fate" of halophyte protein, minerals, and trace elements and increases the understanding of these underutilized indigenous edible plants as future functional foods.

A Comparative Study on Changes in Protein, Lipid and Meat-Quality Attributes of Camel Meat, Beef and Sheep Meat (Mutton) during Refrigerated Storage.

An in-depth characterisation of protein and lipid fractions and changes in the physicochemical and meat-quality attributes of camel meat, beef and mutton over 9 days of refrigerated storage was investigated. The lipids of all the meat samples, especially those in camel meat, underwent significant oxidation in the first 3 days of storage. A decrease in pigment and redness (a* value) with an increase in the storage time was noticed in all the meat samples, suggesting the oxidation of the haem protein. The mutton samples displayed greater protein extractability, while the protein solubility values in all the meat samples were similar, and these varied as storage progressed. The drip loss percentage in camel meat and mutton were two times higher than in beef, and it increased during storage period. The textural properties of fresh camel meat were higher than mutton and beef, and these decreased during day 3 and 9, respectively, indicating the proteolysis and the degradation of the structural proteins, which were also evident from the SDS-PAGE pattern.

Nutritional and techno-functional properties of Australian Acacia seed flour: Effects of roasting on chemical composition, physicochemical properties, and in vitro digestibility and intestinal iron absorption.

Acacia seed (AS) is rich in protein and iron but contains protease inhibitors that can reduce protein digestibility (PD). The seeds are generally roasted prior to consumption, although no information on the PD of roasted AS is available. This study investigated the effect of roasting time (5, 7 and 9 min at 180 °C) on the chemical composition, physicochemical properties, and in vitro PD and intestinal iron absorption of three wild harvested Australian AS species, Acacia victoriae, A. coriacea and A. cowleana. Roasting A. victoriae and A. coriacea seeds for 7 min significantly increased PD in the seeds by 36 and 61 %, respectively. A 9-min roasting time was required to achieve 75 % reduction in trypsin inhibitor activity in A. coriacea seed, while a shorter roasting time (RT) was sufficient to achieve similar reduction rates in the other two Acacia species. Among the functional properties, water and oil absorption capacities were significantly enhanced as RT increased. The starch granules in 7- and 9-min roasted A. victoriae seed flour detached from the protein matrix while random coil increased in 7-min roasted A. victoriae and 9-min roasted A. coriacea and A. cowleana, thus, contributing to enhanced PD. Although the SDS-PAGE in 7- and 9-min roasted A. cowleana samples showed reductions in the intensity of bands for high molecular weight proteins, PD was not affected by RT. However, intestinal iron absorption was not significantly affected by roasting as compared to raw digesta samples. Compared to commercial roasted Acacia seed, the considerably shorter RT used in this study improved PD in the AS flour with less adverse effects on techno-functional properties.

Effects of incorporating processed Acacia seed as an emulsifying agent on the quality attributes of beef sausage.

In this study, partial or full replacement of 6% soy protein isolate (SPI) with 2, 4 and 6% roasted Acacia seed flour (ASRo) and Acacia seed protein concentrates (ASPC) in emulsified beef sausage were investigated. Emulsion stability and cooking loss were lower in samples formulated with ASPC at all levels and control samples compared to ASRo formulated samples. ASRo generated softer and less chewy sausages than ASPC. Cooked 2% ASPC sausages had similar L* and a* values as the control but with lower colour difference (ΔE) values that were similar to cooked 6% SPI sausages' values. An organized protein network structure was observed in the sausages formulated with ASPC at all levels and in the control samples. Therefore, ASPC, particularly at 2 and 4% inclusion, can be used as a functional ingredient to prepare emulsified beef sausages with good quality attributes.

Effect of frozen storage on the biochemical composition of five commercial freshwater fish species from River Nile, Sudan.

Postharvest processing and preservation of fish have great influence on fish quality and consumption. Freshwater fish in Sudan are facing problems related to bad handling and improper storage which reduce their quality. This study investigated the changes in the chemical composition, mineral contents, pH and acid value during storage (-18°C) of five commercial fish species (Bagras bayad, Lates niloticus L., Mormyrus casahive L., Oreochromis nilotica L., and Synodrontis schall) from the River Nile coast of Sudan. The fish species are rich in protein (17.22%-23.60%) but have low fat and ash contents. Frozen storage of the fishes for 45 days reduces their protein contents while the fat and ash contents were increased (p ≤ .05). Potassium and iron are the predominant major and trace minerals and their values were increased with storage period. The pH range from 5.74 (O. niloticus) to 6.24 (B. bayad) while acid value range from 0.02 (M. casahive) to 0.12 (L. niloticus). Both pH and acid values increased with storage period. In conclusion, storage of these fish species for up to 45 days did not adversely affect their nutritional value.

Correction: Shelat, K.J.; et al. Overall Nutritional and Sensory Profile of Different Species of Australian Wattle Seeds (Acacia spp.): Potential Food Sources in the Arid and Semi-Arid Regions. Foods 2019, 8, 482.

The authors wish to make the following correction to the paper [1]:The title of Table 3 "Amino acid (g/100 g dry weight) profile of four different species of wattle seeds" should be changed to "Amino acid (mol% dry weight) profile of four different species of wattle seeds" [...].

Mid-Infrared Spectroscopy as a Rapid Tool to Qualitatively Predict the Effects of Species, Regions and Roasting on the Nutritional Composition of Australian Acacia Seed Species.

In recent times, the popularity of adding value to under-utilized legumes have increased to enhance their use for human consumption. Acacia seed (AS) is an underutilized legume with over 40 edible species found in Australia. The study aimed to qualitatively characterize the chemical composition of 14 common edible AS species from 27 regions in Australia using mid-infrared (MIR) spectroscopy as a rapid tool. Raw and roasted (180 °C, 5, 7, and 9 min) AS flour were analysed using MIR spectroscopy. The wavenumbers (1045 cm-1, 1641 cm-1, and 2852-2926 cm-1) in the MIR spectra show the main components in the AS samples. Principal component analysis (PCA) of the MIR data displayed the clustering of samples according to species and roasting treatment. However, regional differences within the same AS species have less of an effect on the components, as shown in the PCA plot. Statistical analysis of absorbance at specific wavenumbers showed that roasting significantly (p < 0.05) reduced the compositions of some of the AS species. The results provided a foundation for hypothesizing the compositional similarity and/or differences among AS species before and after roasting.

Effects of drying methods and maltodextrin on vitamin C and quality of Terminalia ferdinandiana fruit powder, an emerging Australian functional food ingredient.

BACKGROUND: Terminalia ferdinandiana, common name Kakadu plum (KP), fruit is a valuable source of vitamin C, and its concentration can be used as a quality index of KP products, such as dried fruit powder. The present study investigated the effects of two drying methods (freeze-drying and oven-drying) and the addition of maltodextrin (0-25%) on vitamin C, Maillard products, and overall quality of KP fruit powder. RESULTS: Freeze-drying was a better dehydration technique than oven-drying in retaining vitamin C, reducing the formation of non-enzymatic browning and oxidation products, and improving powder colour (P < 0.05). Non-enzymatic browning products (furfural and 5-hydroxymethyl furfural) were generated in the oven-dried samples as a function of heating and high water activity. Maltodextrin acted as a vitamin C stabilizer in protecting vitamin C from oxidation, and significantly improved the colour attributes of the final dry products. Incorporation of 10-15% maltodextrin could reduce the percentage loss of vitamin C from 8.1% to 3.4% and 18.9% to 11.4% (compared with the control) during freeze-drying and oven-drying, respectively. Scanning electron micrographs revealed differences in the microstructures of the KP powder processed by the two drying methods with different levels of maltodextrin. Multivariate data analysis (principal component analysis) showed separation between the oven-dried and freeze-dried samples, and also suggested that addition of maltodextrin of 7.5-10% and 10-15% are effective for preserving vitamin C and other quality properties of the freeze- and oven-dried KP powder samples, respectively. CONCLUSION: The results obtained are important for the KP industry, including Indigenous enterprises, in selecting the most appropriate drying method for KP fruit in terms of quality and sustainability. © 2021 Society of Chemical Industry.

Nutritional, anti-nutritional, antioxidant, physicochemical and functional characterization of Australian acacia seed: effect of species and regions.

BACKGROUND: Acacia seed (AS) is an underutilized legume widely distributed in the world, with majority of the species (>70%) found in Australia. Generally, the seeds are not only rich in protein, dietary fibre and potassium, but also possess anti-nutritional compounds. In recent years, there have been an increase in the cultivation of some Australian acacia species such as Acacia victoriae, Acacia cowleana and Acacia coriacea from different regions. However, there is limited information on the composition, anti-nutrients, antioxidant and functional properties of flour from these widely grown Australian AS species. Thus, the present study aimed to assess the properties of these Australian AS species from different geographical regions. RESULTS: The A. cowleana and A. coriacea were characterized by high protein, fat, potassium and soluble carbohydrate. However, higher starch and fibre contents were present in A. victoriae. Greater amounts of anti-nutrients, total phenolics and flavonoids were found in A. cowleana and A. coriacea seeds, whereas A. victoriae had higher 2,2-diphenyl-1-picrylhydrazyl radical-scavenging capacity. A. victoriae and A. coriacea demonstrated the highest water absorption and solubility index, respectively. However, A. cowleana showed the highest oil absorption index. There was less variation in the composition and properties within species from different regions. CONCLUSION: All samples showed promising nutritional characteristics, although with sufficient diversity to indicate that Australian acacia seeds can be utilized to develop a range of new (functional) food products. Overall, the information obtained will help the food industries with the selection of AS species for food application.

Acacia seed proteins: Low or high quality? A comprehensive review.

The popularity of adding value to indigenous plant protein sources has increased due to the rise in the world population, high costs of animal protein as compared to plant proteins, and an increase in the consumer awareness of the nutritional and functional roles of dietary plant protein. Seeds of acacia plants (containing over 1,350 species) have considerable amount of protein (18.25% to 35.5%) and nutritionists have shown great interest in assessing the quality and functionality of proteins from these protein-rich plants. In this review, the overall nutritional and health-promoting properties of acacia seed (AS) species are introduced. Extraction, quality, and functional properties of proteins from different AS species are discussed. Furthermore, anti-nutritional components and protease inhibitors present in AS species and the effects of processing methods applied to lower the levels of anti-nutrients are also discussed. Previous applications of AS in food formulations are highlighted. This review aims to provide updated findings that have been reported on AS proteins and to highlight areas for further studies in order to increase the utilization potential of the seeds.

Optimization of ultrasound-assisted extraction of phenolic compounds and antioxidant activity from Argel (Solenostemma argel Hayne) leaves using response surface methodology (RSM).

In this study, phenolic compounds were extracted from Argel leaves using an ultrasound-assisted extraction (UAE) method. The extraction parameters (sonication temperature, time, and ethanol concentration) were optimized using a response surface methodology (Box-Behnken design), in order to maximize the total phenolic content (TPC) and 1,1-diphenyl-2-picrylhydrazyl (DPPH) scavenging activity of Argel leaf extracts (ALEs). The phenolic compounds of the ALEs obtained under optimized conditions were also identified. The optimum UAE conditions for achieving maximum TPC (72.27 g gallic acid equivalents kg-1 DW) and DPPH scavenging activity (86.15%) were a 60 °C temperature, a 37.07 min duration, and a 39.14% ethanol concentration. Under these conditions, the experimental values of TPC and DPPH scavenging activity were 73.02 g GAE kg-1 and 85.56%, respectively, which agreed with the predicted values. In addition, the major phenolic acids found in ALEs under the optimized extraction conditions were sinapic, p-coumaric, and ferulic acid. Overall, the findings of this study demonstrated the suitability of UAE and the success of RSM in optimizing the extraction conditions of bioactive compounds from ALEs.

Assessment of oxidative stability and physicochemical, microbiological, and sensory properties of beef patties formulated with baobab seed (Adansonia digitata) extract.

The present study was conducted to evaluate the oxidative stability and the physicochemical, microbiological, and sensory properties of beef patties formulated with different concentrations (1%, 2%, and 3%) of baobab seed extract (BSE) during storage at 4 °C. The BSE contained a considerable number of phenolic compounds and exhibited antioxidant and antimicrobial activities (both on gram-positive and negative bacteria). The chemical composition of the patties was not altered by BSE treatment. However, the addition of 2% and 3% BSE improved the lipid stability and enhanced the antioxidant activity of beef patties during storage. Furthermore, the shelf-life of patties formulated with 2% and 3% of BSE increased from 7 days (control group) to 21 days. Moreover, the patties formulated with BSE received overall acceptability in the sensory evaluation. In conclusion, the inclusion of 2% or 3% BSE could be recommended as a natural antioxidant additive in beef patties.

Effect of solid-state fermentation on proximate composition, anti-nutritional factor, microbiological and functional properties of lupin flour.

The effects of solid-state fermentation (SSF) with Aspergillus sojae, Aspergillus ficuum and their co-cultures on proximate composition, anti-nutritional factor, microbiological and functional properties of lupin flour (LF) were investigated. Fibre fractions, in vitro enzyme protein digestion (IVPD), total phenolic contents, protein molecular distribution and colour attributes were also evaluated. Samples differed in their proximate composition except ash and fibre contents. The microbiological counts of the fermented LFs were generally higher (p < 0.05) than that of the unfermented LF. Phytic acid content and IVPD decreased (p < 0.05) in the fermented LFs. Also, the fermented LFs showed decreased (p < 0.05) water absorption capacity but increased swelling capacity. In addition, fermented LFs demonstrated reduction in colour attributes. Thus, the study indicated that SSF using Aspergillus sojae and Aspergillus ficuum can influence the physical, chemical and functional properties of LF. LF has great potentials in developing new nutritious food products and feed formulations when subjected to SSF.

Bioactive compounds from date fruit and seed as potential nutraceutical and functional food ingredients.

Date palm is an important fruit bearing tree grown widely in the arid and semi-arid regions of the world. The date fruit and its by-products, such as seeds, have both nutritional and medicinal value. However, date fruit and seeds have not been fully considered as potential functional food ingredients to develop foods with promising health benefits. Based on the available information in the literature, fruit and seed of date palm are rich in phytochemicals, such as phenolics, anthocyanin, carotenoids, tocopherols, tocotrienols, phytosterols and dietary fiber. In addition, they were reported to possess several beneficial health properties explored under in-vitro and in-vivo conditions. Further research in this area would provide valuable information for the potential utilization of date fruit and seed as functional food ingredients. This review presents a comprehensive information about the bioactive compounds and nutraceutical properties of different varieties of date fruit and seed, as well as the potential for using them as functional food ingredients.

Overall Nutritional and Sensory Profile of Different Species of Australian Wattle Seeds (Acacia spp.): Potential Food Sources in the Arid Semi-Arid Regions.

Wattle seed (Acacia spp.) is a well-known staple food within indigenous communities in Australia. A detailed investigation of the overall nutritional and sensory profile of four abundant and underutilized Acacia species-A. coriacea, A. cowleana, A. retinodes and A. sophorae-were performed. Additionally, molecular weight of protein extracts from the wattle seeds (WS) was determined. The seeds are rich in protein (23-27%) and dietary fibre (33-41%). Relatively high fat content was found in A. cowleana (19.3%), A. sophorae (14.8%) and A. retinodes (16.4%) with oleic acid being the predominant fatty acid. The seeds contained high amounts of essential amino acids (histidine, lysine, valine, isoleucine and leucine). A. coriacea is rich in iron (43 mg/kg), potassium (10 g/kg) and magnesium (1.7 g/kg). Pentose (xylose/arabinose), glucose, galactose and galacturonic acids were the major sugars found in the four species. Raw seeds from A. sophorae, A. retinodes and A. coriacea have the highest protein molecular weight, between 50-90 kDa, 80 kDa and 50-55 kDa, respectively. There was variation in the sensory profile of the WS species. This study showed that the four WS species have good nutritional value and could be included in human diet or used in food formulations.

Effect of Traditional Processing on the Nutritional Quality and in vivo Biological Value of Samh (Mesembryanthemum forsskalei Hochst) Flour.

Roasting improved the determined protein and carbohydrate content of the flour compared to raw flour (p < 0.05). Baking enhanced the determined moisture and ash content of the flour compared to all treatments (p < 0.05). Similar amino acid content was found in both raw and treated flours with glutamic acid, glycine, arginine, and aspartic acid being predominant. Cooking reduced the total aromatic and non-essential amino acid content whereas roasting reduced the total essential amino acid content of samh flour. All treatments significantly (p < 0.05) decreased the antinutritional factors compared to untreated raw flour. Baking decreased the trypsin inhibitor activity by almost 98.7% whereas cooking reduced phytate and tannin content by 38.5% and 10.8, respectively. Roasting and baking significantly (p < 0.05) improved the in vitro protein digestibility of the flour. In vivo, the true faecal nitrogen digestibility of rats was significantly (p < 0.05) enhanced by all treatments. Baking and cooking increased (p < 0.05) the net protein utilization and biological value of the flour. Overall, the treatments improved the nutritional quality of samh flour.