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Insects have been considered alternative foods, mainly as sources of protein. The inclusion of insects in the human diet can help meet the growing demand for food, whether consumed directly or as ingredients in other formulations. In recent years, there has been great interest in using insect proteins as a substrate to obtain bioactive peptides. This review provides an overview of obtaining bioactive peptides, addressing the advantages of using insects as a protein substrate, as well as the challenges associated with their use. Techniques for simulating gastrointestinal digestion, microbial fermentation and application of commercial enzymes were described as suitable methods for obtaining peptides. The principles of antioxidant, antidiabetic and antihypertensive properties have been elucidated. Considering an alternative use of peptides as ingredients in other food formulations, possible changes in their bioactivities were reported. This could result from the interaction of peptides with phenolic compounds and their involvement in the Maillard reaction. Finally, allergenic and regulatory aspects were discussed as the main challenges in using insects as a hydrolysis substrate.

Food waste (FW) is a global problem and a hidden opportunity for the value-added product conversion. Thus, food waste valorization is a growing science toward the waste-to-wealth conversion. FW can be generated either on a domestic or industrial scale, even if a zero-waste policy is practiced, owing to the unavoidable portion of food waste generated during the processing, cooking, and transportation of food materials. Previous studies have reported that FW is a potential sink for valuable bioactive molecules and bioenergy. In addition, earlier reports noted that the application of contemporary and advanced valorization processes for food waste management was limited to developed countries, and a significant portion of FW remained untouched owing to the lack of research in the rest of the global arena. As a result, this comprehensive review scrutinized several vital and advanced options for the sustainable valorization of global food waste, focusing on its prospects and challenges. In particular, this study deciphers the potential of unexplored valorization approaches and integrated biorefinery strategies for the holistic management of global food waste. Owing to the unavoidable waste generation during food processing, handling, and transportation, the sustainable valorization of FW is a phenomenal option for meeting the sustainable development goals (SDGs) of the United Nations (UN). Finally, this review paves the way for adopting sustainable technologies to convert waste into wealth through integrated valorization and biorefinery approaches toward the efficient recycling of global food waste.

The potential of spent coffee grounds (SCG) to act as a replacement fuel material for the malt-drying process during whisky production was evaluated. The extracts of both materials, and the smoke they produced through burning, were subjected to analysis by high resolution 1H NMR spectroscopy. Malts infused with the smokes were similarly studied to gain an understanding of the transfer of chemical species from smoke to grain. In addition, the thermal degradation of peat and SCG were investigated using thermogravimetric analysis and pyrolysis – GCMS. Our studies revealed that, despite some chemical differences between the source materials, the composition of the smoke produced by both is remarkably similar. It may be concluded that the aroma and flavour of the spirit, resulting from substitution of peat by SCG is also likely to be similar, however the presence of additional congeners in the SCG-derived spirit, including furans and methylpyridines, could introduce undesirable off notes.

As one of the world's major crops, oats (Avena sativa L.) require management strategies to increase their yield and quality. This study utilised an unmanned aerial vehicle (UAV) with multispectral image sensors to predict winter oats height (1.18 m at ripening stage) and yield (maximum >7.62 t per ha) using the normalised difference vegetation index (NDVI) and chlorophyll green vegetation index (CI green VI) across three different growth stages (flowering, grain filling and ripening). To corroborate the vegetation indices ground truth data on the measured crop yield, a variety of chemical soil health indicators (i.e. nitrogen, phosphorus, potassium, pH, and soil organic matter), and a crop quality indicator (β-glucan) were determined. A hierarchical multinomial logistic regression machine learning model was developed to predict the oats yield incorporating the chemical soil health indicators and crop quality indicator. The determined ‘combination model’ using the CI green VI, with 16 soil feature parameters, showed good specificity (0.87), sensitivity (0.95), and accuracy (0.93) at estimating the very high oat yield. Finally, the study provides the range of soil nutrient levels and the crop quality indicator that farmers must maintain to gain the highest oat yield at harvest. The findings of this research study will be particularly valuable as a Precision Agriculture management strategy for maximising winter oat yield and quality.

Microwave processing is used in industry for drying food commodities as it improves the quality of products and reduces the drying period. In the present study, the effects of microwave power of 600 W (105 and 100 min), 800 W (95 and 90 min), and 1000 W (80 and 65 min) and temperature (60 and 70 °C) on the drying kinetics and quality of microwave-dried shrimp were investigated. The results revealed that increasing the microwave power and temperature increase the drying rate. During the drying process, protein, fat, and ash content increased, whereas the moisture content decreased. The energy value of the dried shrimp increased from 54.41 to 287 kcal g−1. The yield of dried shrimp was in the range of 24–25%. The pH, trimethylamine nitrogen (TMA-N), total volatile base nitrogen (TVB-N), free fatty acids (FFA), thiobarbituric acid-reactive substances (TBARS), and non-protein nitrogen (NPN) values increased slightly in the dried shrimp. Moreover, the hardness of the fried shrimp decreased, while its springiness, gumminess, cohesiveness, and chewiness increased slightly. The lightness (L*), redness (a*), yellowness (b*), chroma, browning index, whiteness index, and ΔE increased in the dried shrimp. The results indicated that the quality of the dried shrimp and drying time decreased when the microwave power was increased.

Natural colorants have gained increased popularity among consumers and food producers due to their reputation as safer and healthier alternatives to commonly used artificial analogues. These natural pigments can be obtained from by-products resulting from food processing, such as the fruit peels of the Brazilian species Eugenia brasiliensis and Eugenia involucrata, thus contributing to the valorisation and circularity of these undervalued raw materials. Therefore, since these fruit peels present anthocyanin concentrations that justify their exploitation, this study aimed to optimize and compare the recovery of these pigments from these plant by-products using heat- and ultrasound-assisted extraction (HAE and UAE, respectively) methods. For process optimization, a central composite rotatable design coupled with response surface methodology was implemented, considering time, ethanol/water ratio, and temperature (for HAE) or ultrasonic power (for UAE) as relevant independent variables. While UAE resulted in higher extraction yields (40–42%, w/w), HAE led to higher anthocyanin contents (18 mg g−1 from E. involucrata and 323 mg g−1 from E. brasiliensis). Furthermore, the HAE global optimum involved only 2 min of processing. Both theoretical models were experimentally validated by applying the model-predicted extraction conditions, and the obtained anthocyanin-rich extracts were analysed for colour and in vitro bioactive properties. In general, the extraction method did not greatly affect the colour or the antimicrobial and cytotoxic activities of the extracts. However, only E. brasiliensis extracts showed cytotoxicity on human tumour cell lines, which also stood out for their antioxidant activity, possibly due to the higher anthocyanin content. Thus, Eugenia spp. fruit peels could be an alternative renewable source of natural food colourants with bioactive properties. Nonetheless, since E. brasiliensis extracts displayed moderate toxicity towards normal cells, the toxicity threshold should be further investigated to ensure the safe exploitation of this raw material as a possible source of natural food colourants.

The dielectric properties of cereal grain flours are studied by varying the moisture content and density, using a novel metamaterial Wire Split Ring Resonator (WSRR) based sensor working in the microwave frequency range at room temperature. Four types of cereal grains ground into fine powders are used as the test samples. The WSRR sensor is kept in the electromagnetic field that exists between two monopole antennas connected to the receiving and transmitting ports of a Vector Network Analyzer (VNA) which serves as the measuring device. The LC resonance behavior of the WSRR on interacting with the electromagnetic field and the shift in its resonance frequency in response to any changes in the dielectric environment around it form the basis of sensing. The variation in the moisture content and density of cereal flour samples will cause corresponding changes in the capacitive environment of the sensor which is reflected as the resonance frequency shift. From the resonance–density calibration plot, the maximum packing density of cereal grain powders is found which is useful in determining the efficient use of the available packing space. The moisture content, an essential requirement in ensuring the shelf life of cereal grain powders, is analyzed from the resonance–moisture calibration plot. This simple and accurate metamaterial-inspired measuring technique may find wide applications in the food industry in optimizing the shelf life and packing space of cereal grain powder products.

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Isochoric freezing, a cutting-edge preservation technique, has gained significant attention in recent years due to its potential to revolutionize various industries, including food preservation, biotechnology, and cryopreservation. It effectively increases the shelf life of farm-fresh produce while reducing browning reactions. This review focuses on presenting the state-of-the-art isochoric freezing of foods, emphasizing the fundamental principles that make it special and comprehending its impact on food quality and food and non-food applications, taking papers published in the last ten years into account. In contrast to conventional nonthermal activities, isochoric freezing can be achieved without using additional apparatus such as elevated pressure equipment or pulsed electric fields using simple, inexpensive, rigid closed-volume containers like house refrigerators or commercial cold storage facilities. Recent break-throughs in the field, such as food applications of isochoric freezing in grape tomatoes, spinach, potatoes, sweet cherries, and pomegranates, and non-food applications in mammalian cells, pancreatic islets, Escherichia coli, nematodes, and rat hearts, are highlighted. Hence isochoric freezing is a value-added process that helps to enhance food safety, and therefore on-going research and development in this area can make it an easily accessible preservation method in the near future.

The rapidly increasing global population reached 8 billion in November 2022, which is further projected to reach 9.7 billion by 2050. The question of how to sustainably feed the growing population has become a major concern for many countries. In terms of the global protein supply, animal-based protein sources continue to play a dominant role, particularly in developed countries. However, there is growing interest in plant-based protein sources, particularly in the form of meat analogues, as a way to provide a more sustainable and ethical source of protein. To ensure an adequate supply of protein for the world, it's important to promote sustainable and equitable food systems that provide a variety of nutritious and affordable food options, including both animal and plant-based sources of protein. Additionally, investment in research and development of new plant-based protein sources, as well as new technologies to improve the efficiency and sustainability of animal agriculture, can help to ensure a secure and healthy protein supply for the world's growing population. Cereal and legume combinations play a critical role in the development of meat analogues because they provide an important source of protein that can be used to mimic the taste, texture, and nutritional properties of meat. When combined, cereal and legume products can provide a complete source of protein that is comparable to that found in animal-based products. In terms of developing meat analogues, cereal and legume combinations can be used to make products such as veggie burgers, meatless meatballs, and other plant-based meat alternatives. These products can be made using a variety of techniques, including grinding, texturizing, and extruding, to create a product that mimics the taste, texture, and nutritional properties of meat. The current article revolves around the theme of the potential of cereal legume combinations, current practices, challenges faced, novel ingredients and technological practices in developing sustainable meat analogues.

High-moisture extrusion technology emerges as a prime choice for preparing alternative protein products with a meat-like texture. However, the nutritional aspects of these products, prepared from a blend of plant and animal proteins, remain unclear. This study investigated the nutritional qualities of extrudates derived from soy protein isolate (SPI) and surimi, exploring ratios ranging from 90 : 10 to 50 : 50, with varied extrusion temperature (125 °C, 135 °C and 145 °C) and moisture content (65%, 70% and 75%). Results revealed the significant role played by surimi in enhancing both amino acid and fatty acid contents in high-moisture extrudates originating from SPI and surimi. Notably, the first limiting amino acid score (AAS/MET + CYS) increased significantly from 88.82 to 109.50 as the surimi content increased from 10% to 50%. Moreover, the levels of docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) in the extrudates significantly increased, concurrently reducing the n-6/n-3 fatty acid ratio. At a higher moisture content (70–75%), increasing extrusion temperature bolstered the fatty acid content in the extrudates. When the SPI–surimi ratio was 90 : 10, the gastric digestibility of the extrudates was the highest (60.20%). Meanwhile, the highest small intestinal digestibility was 93.07% at a SPI–surimi ratio of 70 : 30. At lower extrusion temperatures (125–135 °C), increasing moisture content led to a notable increase in the small intestinal digestibility of the extrudates. SPI–surimi ratios and hydro-thermal combined parameters have significant effects on the in vitro digestibility of high-moisture extrudates. This study could contribute to the improvement of nutritional qualities of alternative protein products based on mixed proteins from soy and surimi.

Rice bran (∼8–10% of the total rice weight), generated in large quantities during rice processing, is an underutilized rice processing byproduct. The objective of this study was to upcycle defatted rice bran into starch and protein-based nanoporous aerogels using supercritical carbon dioxide (SC-CO2) drying. Specifically, crude starch-1, crude starch-2, and protein aerogels were prepared at three different concentrations of 10, 15, and 20% (w/w). The generated aerogels were characterized for their morphology, crystallinity, chemical interactions, textural properties, solubility, and thermal stability. The aerogels (15%, w/w) prepared from rice bran crude starch and protein formed a three-dimensional interconnected open porous structure. At this concentration, protein aerogels revealed the highest surface area of 25.3 m2 g−1, a pore size of 22 nm, and a pore volume of 0.13 cm3 g−1, whereas crude starch-1 and crude starch-2 aerogels had surface areas of 19.7 and 21.3 m2 g−1, pore sizes of 22 and 18 nm, and pore volumes of 0.10 and 0.09 cm3 g−1, respectively. All the aerogels exhibited densities lower than 0.3 g cm−3 with porosities higher than 82%. Overall, this study generated high-value starch and protein-based aerogels that can be used for developing functional foods to deliver bioactive compounds, thereby adding value to the underutilized defatted rice bran.

The aim of the work was to investigate the effect of different packaging materials and storage temperatures on the stability and in vitro properties of microencapsulated spray-dried synbiotic kidney-mung bean beverage (KMB) powder. The formulation for the synbiotic KMB powder has been explored in our previous work. The present study focuses on the evaluation of the shelf-life of the same synbiotic KMB powder. The synbiotic powder was packed in polypropylene and aluminum laminates and stored at 25, 30, and 35 °C. The survivability of probiotic Lacticaseibacillus casei in encapsulated spray-dried powder was studied under simulated gastric conditions for 70 days. At all three storage temperatures, the count remained >108 CFU mL−1 for the first 21 days. Additionally, moisture content increased and color value (L*) decreased with increasing storage time, irrespective of packaging material. The encapsulated synbiotic powder in Al-laminate pouches also showed better prebiotic activity when compared to PP laminates. An acceptable sensory score (6 out of 10) and low microbial load (<106 CFU mL−1) also suggested that the shelf life of synbiotic KMB powder in polypropylene and aluminum laminates was 63, 35, and 35 days at 25, 30, and 35 °C, respectively.

Pomegranate fruit is highly prone to moisture loss due to the plentiful micro-pores and slits in the skin, despite having a thick rind. Water loss results in a huge financial loss to the industry through direct loss of marketable fresh weight and the associated diminished commercial value of affected fruit. Plastic packaging and surface coating are broad rivals as water loss control technologies and have attracted increased attention in the fruit industry in the last decade. In this present study, weight loss control techniques including conventional plastic packaging (liner packaging and shrink wrapping) and environmentally sustainable surface coating/waxing technologies were investigated on ‘Wonderful’ pomegranates harvested at commercial maturity with total soluble solids (TSS) of about 16.75 °Brix. Secondly, the different methods of waxing application including dipping, brushing and spraying were investigated. Furthermore, fruits were half dipped in wax by dipping only the top or bottom half of the fruit and this was to assess weight loss variation within individual fruit. Batch 1 fruits were stored at 7 °C and 90% RH for 42 d and thereafter transferred to shelf conditions of 23 °C and 58% RH for 8 d, simulating the maximum sea freight duration from South Africa to Europe across the Atlantic Ocean, followed by open-shelf marketing before consumption. Batch 2 fruits were immediately stored under shelf conditions for 16 d, to simulate prolonged shelf conditions of fruit without a cold storage regime. The fruit weight loss, decay incidence, respiration rate, external total colour difference (TCD), total soluble solids and titratable acidity were investigated and scanning electron microscopy (SEM) was carried out on waxed fruit. The weight loss was highest in control fruit (7.7%), followed by bottom-dip waxed (6.0%), top-dip waxed (5.8%), wax sprayed (4.8%), wax brushed (4.6%), wax dipped (4.0%), and liner packaged (2.1%) and least in shrink wrapped (0.8%) fruit, by the end of the 42 d of cold storage. Dipping was the best wax application method in controlling pomegranate fruit weight loss as compared to half waxing (top and bottom dipped), brushing and spraying application methods. Furthermore, shrink wrapping, liner packaging and wax dipping best maintained a lower TCD and thus better-preserved fruit appearance compared to the rest of the treatments.

Guava (Psidium guajava L.) is a nutritious fruit of sub-tropical regions that displays climacteric characteristics and short postharvest life. The quality of guava fruit deteriorates within two to three days at ambient temperatures; therefore, specific practices are needed to preserve the quality and increase the shelf life of guavas. In the present work, we aimed to assess how various packing materials affected the shelf life and quality of guava fruit (cv. Gola) stored at room temperature. Guava fruits were stored for a period of 20 days in different packing materials such as biodegradable packaging (BDP), corrugated fiber box (CFB), polypropylene (PP), high density polyethylene (HDPE), low density polyethylene (LDPE) and polystyrene (PS). During the storage period, transitions in multiple quality metrics were observed at predetermined intervals of four (4) days. According to the findings, each packing material significantly affected the fruit's quality in comparison to control samples. During the storage period, there was a natural decline in firmness (93.4%), ascorbic acid (55.6%), and TPC (48.6%); however, the packaged fruit samples showed a considerably slower rate of reduction (p < 0.05) than the unpackaged control samples. Moreover, respiratory gases were effectively suppressed under packaging viz. HDPE (ethylene; 8.76 μL kg−1 h−1, CO2; 19.76 mL kg−1 h−1) and BDP (ethylene; 10.16 μL kg−1 h−1, CO2; 21.37 μL kg−1 h−1), respectively. In terms of enzyme dynamics, un-packed fruit samples had relatively low CAT activity (69.45 U mg−1 protein), while guava fruits that were packed in BDP exhibited much increased CAT activity (82.28 U mg−1 protein). Likewise, PPO activity was significantly inhibited in packaged fruit samples. Among the different packaging employed, biodegradable packaging, PP, and HDPE exhibited better overall retention of quality attributes during 20 days of storage under ambient conditions. The study's outcome should open up new opportunities for the fruit and vegetable sectors while also offering a cost-effective approach to preserving fresh guavas and increasing their economic potential.

This study evaluated the quality traits and oxidative storage stability of meat nuggets enriched with immature moringa pod powder (MPP) at 1.5% and 3.0% levels in comparison to control samples over a 12 day storage period under refrigerated conditions. MPP is a rich source of protein (18.96%), ash (7.42%), dietary fiber (DF, 43.64%), and a notable concentration of total phenolics (TP, 9.20 mg GAE g−1). The MPP analyzed by GC-MS showed the presence of different phenolic acids, such as cinnamic, benzoic, phthalic, vanillic, p-coumaric, ferulic, and caffeic acids and catechin, with concentrations ranging from 1.031 ppm to 2.949 ppm. Incorporating MPP as a source of DF had a negligible impact (p > 0.05) on the pH levels of both the emulsion and meat nuggets. However, it notably improved the emulsion stability, cooking yield, ash content, DF content, and TP content of the nuggets. Immature MPP at the 3% level significantly (p < 0.05) influenced the lightness and redness of the nuggets. Moreover, the MPP in meat formulations demonstrated a significant (p < 0.05) ability to inhibit lipid oxidation and had no adverse effect on the sensory attributes of meat nuggets. This finding highlights the potential of MPP to enhance oxidative stability during refrigerated storage for up to 12 days. This study suggests that immature moringa pods can serve as a natural functional ingredient by improving the nutritional quality and functionality of meat products while extending their shelf life through their antioxidative properties.

Food waste-induced environmental damage has been a primary concern for environmentalists for decades. Several studies have proven that greenhouse gases emitted by food waste worldwide are causing more damage than coal power plants in some cases. Over the years, many solutions have been proposed, but the problem is yet to be resolved. This mini-review aims to discuss some of the recent solutions proposed by researchers around the world. A discussion about the effective campaigns intended to target specific demographics to encourage sustainable consumer behavior, successful models designed to implement a systemic production process, and sustainable waste management programs is presented. This study emphasizes taking successful small-scale campaigns and models and utilizing them on a larger scale. It will help reduce food waste by consumers and producers in the long term. Biohydrogen and biogas production through anaerobic digestion (AD) of organic food waste sounds very sustainable and interesting. However, the supply chain optimization, economics involved and land for installing AD, and low-value of the end-products are the challenges that need to be addressed.

To feed the increasing world population, finding sustainable sources of meat substitutes has become necessary. Mycoprotein, derived from filamentous fungi, is a good meat alternative as it provides nutrition and has some additional health benefits over conventional meat. It can act as a prebiotic, antioxidant, blood cholesterol level regulator, and blood glucose level regulator. It also plays a significant role in muscle protein development. Mycoprotein production is carried out by submerged fermentation, solid-state fermentation, or surface culture method. The yield of the mycoprotein depends on the type of microorganism or substrate used for the production. Different research studies have proved that mycoprotein produced by submerged fermentation has a higher yield and more nutritional benefits. The Food and Drug Administration gave certain fungal species the Generally Recognized as Safe (GRAS) status. Some of the species include Monascus purpureus, Aspergillus oryzae, Paradendryphiella salina, Neurospora intermedia, Rhizopus oryzae and Fusarium venenatum. This fungal product has less environmental impact than conventional meat protein. The carbon footprint of mycoprotein is 10 and 4 times less than that of beef and chicken, respectively. Although some limitations are there, i.e., less protein, nausea, vomiting, sub-chronic toxicity, and allergic reactions, mycoprotein may be widely accepted by the vegetarian population in the future as a meat replacer.

Microalgae are promising plant-like food sources rich in proteins and bioactive compounds with nutraceutical potential. This research investigated the health-promoting effects of high pressure homogenisation (HPH)-treated microalgal suspensions (8% w/v) of Arthrospira and Nannochloropsis species. These microalgal suspensions were treated using HPH at 300 bar, 600 bar, and 900 bar for a single pass. To gain valuable information on the bioavailability of potentially bioactive compounds, gastrointestinal digests obtained after in vitro simulated human gastrointestinal digestion of HPH-treated microalgal suspensions were examined for total phenolics, pigments, and antioxidant activity. Furthermore, their bioprotective potential was evaluated on an oxidatively stressed (induced by hydrogen peroxide) Caco-2 cell culture model system. Results showed that increasing the homogenisation pressure resulted in increased chlorophyll a and carotenoids release for both Arthrospira and Nannochloropsis species. Nannochloropsis sp. experienced an improved phenolics yield with HPH but a similar positive impact of HPH was not observed for Arthrospira sp. probably because of its inherent high phenolic content. Similarly, only Nannochloropsis sp. suspensions showed higher antioxidant activity by FRAP assay at 900 bar treatment. HPH-treated gastrointestinal digests of Arthrospira sp. treated at 600 bar and 900 bar demonstrated cell recovery and viability on stressed Caco-2 cells. However, there was an insignificant bioprotective effect from the HPH-treated Nannochloropsis digests. In general, it appears that the ideal homogenizing pressures for Arthrospira and Nannochloropsis suspensions are 300 and 900 bar, respectively. Overall, this study shows the potential of HPH as an efficient tool to produce functional foods and ingredients, particularly from Arthrospira sp. suspensions.