Many foods, during the production process, generate a lot of by-products that become food waste, with environmental and economic consequences. These byproducts are rich in bioactive compounds, so they could be reused. In this way, to embrace the concepts of the circular economy, waste can be turned in a new raw material. This review is focused on the opportunity to recycling byproduct in a new food through innovative technologies such as zero waste and the reuse of waste parts of food. The aim of the techniques analyzed in this study is the food functionalization: final product obtained with the addition of byproduct improved his nutritional, technological and sensorial characteristic and should be recognized as a sustainable food. This overview makes a critical analysis of the development of the scientific literature available to date on the reuse of food by-products to formulate enriched foods. First, a series of case studies is shown in which food was produced using the zero-waste approach and then a wide range of case studies relating to various food supply chains are discussed in which by-products are generated that can be partially reusable in new foods. In terms of food groups, fruit and vegetable products, the coffee industry, alcoholic beverages (wine and beer), the oil industry, the dairy industry, the by-products of legumes and cereals and the fishing industry have been analyzed.

The objective of this work was to study the effect on physicochemical, rheological and sensory parameters of a yogurt made with ewe milk treated by high hydrostatic pressure compared to a traditional yogurt made with pasteurized milk.

For this purpose, Churra ewe's milk was collected and divided into two batches with their replicas. One batch was subjected to high hydrostatic pressure treatment (600MPa, 6 minutes at 20° C) and the second batch was pasteurized (92° C, 5 minutes).

Fermentation was carried out at 42° C by inoculation of a Lactobacillus bulgaricus and Streptococcus thermophilus started.

Treatment with high hydrostatic pressure significantly (p <0.05) affected the fat content, dry matter and colour parameter b*.

Likewise, yogurts made with milk treated at high pressure did not show significant differences in texture parameters, except for adhesiveness, with respect to yogurts made with pasteurized milk.

At the rheological level, both treatments showed elastic thixotropic behaviour with higher values ​​for elastic modulus (G´), viscous modulus (G´´) and apparent viscosity in yogurts made with pasteurized milk.

Sensory analysis, using a trained tasting panel, resulted in significant differences (p <0.05) in sliminess, creaminess, flavour and overall preference where the high-pressure batches received the best scores.

In conclusion, the treatment showed significant differences, being yogurts made with milk treated with high hydrostatic pressure the best evaluated in the sensory analysis.

Food-to-Food fortification is an emerging technique to enrich nutrient-deficient foods by adding foods with relatively high amounts of one or more than one type of micro and macronutrients. The dried leaves of herbs like basil, marjoram, and spearmint have excellent nutritional properties. These can fortify staple raw materials like rice flour (RF) to produce gluten-free fortified products. Thus, in this research, an attempt was made to find the effect of these dried herbs on the physicochemical and nutritional properties of RF with skim milk powder (SMP) (3% w/w) at different fortification levels (FLs) (1-4% w/w). The physicochemical and nutritional properties viz., water absorption index (WAI), water solubility index (WSI), oil absorption capacity (OAC), water absorption capacity (WAC), solubility (SL), iron (Fe), and proximate analysis was found out. Results showed insignificant (p>0.05) change in all physicochemical properties at 1% addition of marjoram, spearmint, and basil as compared to control (RF + SMP). However, a significant (p<0.05) increase in WAI was noticed at 2% addition of marjoram, spearmint, and basil. Further, no significant (p>0.05) change in WAI was noticed up to the highest FL in all fortificants. Similar behavior was observed with WSI, only in the case of marjoram; however, no significant (p>0.05) change was observed with spearmint at all FLs. In addition, basil at 4% fortification causes a significant (p<0.05) increase in WSI. In WAC, neither marjoram nor spearmint resulted in any significant (p>0.05) change at all FLs except basil at 4%. A similar resulted was noticed with SL. Nevertheless, a significant (p<0.05) color change was observed at all FLs. The iron, protein, and crude fiber were significant (p<0.05) improved at 4%. A similar result was noticed with carbohydrate, energy, and crude fat at a higher FL. The study will help food processors to formulate fortified foods using dried herbs.

Nowadays, 3D food printing, in other words, food layered manufacture, has gained more importance. The most common driving forces behind of using 3D technology in the food sector is designing complex external and internal food structure, customizability of sensorial and nutritional features and the relationship between the sustainability. In this regard, 3D printed cereal-based products, especially cookies are one of the most common food products.

According to studies in which have used 3D printing technology for cookie production, some food additives like hydrocolloids, in particular xanthan gum, could be used to increase mechanical strength in the post-processing steps as baking, frying, or steaming. However, the concentration of hydrocolloids is important due to influencing extrudability and also porosity which could bring about poor textural properties. On the other hand, it is possible to produce 3D printed cookies without hydrocolloids or stabilizers with modifying the cookie recipes by means of changing fat and flour type or concentration of sugar. Besides, applying the pre-heating process in cookie dough could enhance the resistance of deformation and could be implemented as 3D printing inks, which is giving better results in flours with lower starch content rather than higher starch content like tapioca. Moreover, 3D printed technology make also available fortifying cookies with some microalgae like Arthrospira platensis and Chlorella vulgaris, culminate in enhancing printability and stability. Moreover, to obtain novel functional foods with high nutritional properties, pea protein, grape skin powder, jackfruit seed powder, and finger millet powder have also been used in 3D printed cookies. To sum up, 3D printing technology has great potential and is a promising solution for personalized cookies with complex shapes and textures by taking into consideration the contribution of ingredients and printing parameters to produce high quality end-products with higher repeatability and accuracy.

European consumers have a growing interest in new fruits and flavours, which has promoted the production and commercialization of exotic fruits such as goldenberry (Physalis peruviana L., Fam. Solanaceae). Colombia and South Africa are currently the main producers of this fruit, but it can be cultivated in almost all the highlands of the tropics and in several parts of the subtropics given its ability to adapt to a wide range of agroecological conditions [1]. The consumers demand for this small orange berry has also been driven by its nutritional value and health-promoting effects [2]. Although there are different studies about this fruit, the available information is still scarce. Furthermore, the fruit quality attributes can vary depending on the agricultural practices and edaphoclimatic conditions of the growing sites. Therefore, this study was carried out to evaluate the nutritional composition and the in vitro antioxidant and antimicrobial activity of goldenberry cultivated in the Northeast region of Portugal. Goldenberry samples were lyophilized and analysed for their proximate composition (moisture, protein, fat, ash, dietary fibre, and carbohydrates) following official methods of food analysis [3]. The profiles in sugars, organic acids, fatty acids, and tocopherols were characterized by standardized chromatographic methods [3]. The powdered goldenberry sample was also prepared in a hydroethanolic extract used for the evaluation of antioxidant activity (by oxidative haemolysis and lipid peroxidation inhibition assays) and antimicrobial effects against foodborne bacteria and fungi (by serial microdilution methods) [3]. The nutritional analysis revealed high levels of proteins and carbohydrates (manly fructose and glucose) and a lipid fraction consisting mainly of polyunsaturated fatty acids. Citric and ascorbic acids were detected in high amounts, as well as the four tocopherol isoforms. The hydroethanolic berry extract showed capacity for inhibiting haemolytic oxidation and lipid peroxidation, antibacterial effects against Staphylococcus aureus and Bacillus cereus, and antifungal activity against Aspergillus and Penicillium strains. Overall, this work highlighted the nutritional value of goldenberry, which has been pointed out as a functional fruit with a growing expression in the Portuguese market.

Keywords: nutritional value, functional food, sugars/acids, tocopherols, antioxidant, antimicrobial activity.

Acknowledgements:

The authors are grateful to Foundation for Science and Technology (FCT, Portugal) for financial support through national funds FCT/MCTES to CIMO (UIDB/00690/2020); to FCT for the J. Pinela (CEECIND/01011/2018) and L. Barros contracts through the individual and institutional scientific employment program-contract, respectively, and for the M. Añibarro-Ortega studentship (2020.06297.BD); to MICINN for supporting the Ramón y Cajal grant of M.A. Prieto; to FEDER-Interreg España-Portugal programme for financial support through project TRANSCoLAB 0612_TRANS_CO_LAB_2_P; and to the Serbian Ministry of Education, Science and Technological Development for financial support [Contract No. 451-03-9/2021-14/200007].

To the University of Vigo for the mobility aid of the university research staff.

References

1. Monroy-Velandia, D., Coy-Barrera, E., Molecules, 26 (2021) 2756.
2. Ramadan, M. ., Food Res. Int., 44 (2011) 1830–1836.
3. Añibarro-Ortega, M.., Pinela, J., Barros, L., et al., Antioxidants, 8 (2019) 444.

Expanding populations and limited natural resources are leading to demands for alternative dietary proteins. The world food supply needs to be increased to feed the increasing population with the same limited resources. To overcome the hunger problem, alternative protein sources such as fungal “Mycelium” can be regarded as a novel, sustainable and safe dietary protein to support health with limited resources (water, land) having lower carbon footprint. Although, mycelium is rich in various minerals, vitamin D₂, fibers, essential amino acids along with protein, its storage life is relatively short due to its high moisture content (89 % wb). Thus, drying of mycelium would facilitate shelf life enhancement for further processing. Going along the way; cold pressing as a pre-processing step was done to reduce the initial moisture of mycelium so as to reduce the drying time and cost by a significant level. Then, the influence of different drying techniques such as vacuum (VD), microwave (MWD) and freeze (FD) drying methods on quality attributes such as color, microstructure (SEM), water solubility index, water absorption index, bulk and tapped density, and flowability of Pleurotus eryngii was determined. Pressing at 5 N for 30 s reduced drying time by 50-55 % approximately. FD was the most effective which retained the main characteristics of P. eryngii followed by VD and MW. SEM analysis shows that FD sample contains porous fibrous structure whereas MWD and VD sample contains hard structure with less or no pores. Finally, despite the least drying time, MWD and VD damages the structure of P. eryngii whereas nutrient loss is not significant in all the drying processes.

Campylobacter is the leading cause of bacterial foodborne gastroenteritis worldwide. Infections by Campylobacter in humans are generally caused by consuming contaminated foods of animal origin, with poultry, especially chicken, being the main reservoir. The high prevalence of Campylobacter in chicken carcasses and the growing resistance to the most widely used antibiotics has driven EFSA to propose a regulation (2017/1495) containing new microbiological criteria to regulate the presence of Campylobacter in broiler carcasses. In this context, there has been an increase in the number of research aimed at the search for new tools to reduce Campylobacter incidence in chicken meat. The objective of the present work was to evaluate the antibacterial activity of two olive leaf extracts (A y B) against eleven Campylobacter spp. strains (C. jejuni y C. coli) isolated from chicken food chain. Results showed that all Campylobacter strains had resistance to at least one of the eight antibiotics evaluated, and 46% of them were antibiotic multi-resistant. HPLC analysis showed that hydroxytyrosol and oleuropein were the major phenolic compounds in extracts A and B, respectively. Extract A showed a significant antibacterial activity against all Campylobacter strains tested in the present work. The use of a pure standard of hydroxytyrosol confirmed the contribution of this compound to the antibacterial effect of extract A. These results suggest that olive leaves could be used as a source of bioactive compounds to obtain extracts with antibacterial activity against Campylobacter spp potentially applicable to reduce the presence of Campylobacter in chicken carcasses.

Celiac disease is an autoimmune enteropathy that affects the small intestine and is caused by the gliadin fraction of wheat gluten and other alcohol-soluble proteins (prolamines) of barley and rye in genetically predisposed subjects. Nowadays, the only recognized cure for this pathology is the use of gluten-free (GF) products. Although the market of GF products has been increased in the last few years, their improvement is still a challenge for the food industry. Considering the GF bakery products, some of them can result in unappetizing taste with high-fat content. These inconveniences can be minimized or solved by using sourdough fermentation. Sourdough is a stable culture of lactic acid bacteria (LAB) and yeast in a mixture of flour and water. In particular, GF sourdough represents a rich source of naturally occurring LAB and wild yeasts which play important roles in food fermentation. This is mainly due to their potential in improving functional, technological, and probiotics properties contributing to safe and more tasty food. Moreover, exopolysaccharide (EPS)-producing strains can contribute to improving the sensory and rheological quality of the different GF products as well.

This study aims to isolate and characterized the microbial pool from a GF sourdough made with rice flour and to evaluate the ability of selected LAB strains to produce exopolysaccharides (EPS).

The yeast and LAB were isolated in selective agar media. A total of 220 isolates (110 yeasts and 110 bacteria) were obtained. They were taxonomically identified and characterized using both traditional and molecular approaches. Sequencing analysis of the D1/D2 domain of the 26S rRNA and the 16S rRNA genes, for yeasts and bacteria respectively, revealed the occurrence of Saccharomyces cerevisiae as predominant yeasts and Lactiplantibacillus plantarum and Pediococcus pentosaceus as dominant LAB. Regarding the EPS production, 25 strains were able to produce dextran-like EPS with a maximum yield of 2 g/L.

This study allowed to isolate and select promising EPS-producing starter culture for the different type of flour sourdoughs, in particular GF sourdough.

Fishery by-products are rich in biologically active substances and the use of green and efficient extraction methods to recover these high-added-value compounds is of particular importance. In this study, accelerated solvent extraction (ASE) and pulsed electric field (PEF) were used as innovative approaches to recover extracts from rainbow trout and sole side streams rich in high-added-value compounds. Then, evaluate the heavy metals, proteins and their antioxidant capacity. The impact of the obtained extracts on bacterial growth and anti-inflammatory potential was evaluated. The results showed that some extracts could inhibit the growth of pathogenic bacteria, including the ASE rainbow trout skin and the PEF sole viscera extracts, which showed a significant antibacterial activity on Staphylococcus aureus. The PEF sole viscera extract also showed an inhibitory effect on the growth of Salmonella. Some extracts promoted probiotic bacteria growth, including the PEF rainbow trout head and skin extracts promoted Lactobacillus casei growth, while the ASE rainbow trout head and skin extracts promoted Bifidobacterium lactis growth. Even more, some extracts have potential anti-inflammatory properties, such as ASE-rainbow trout-viscera extracts, PEF-sole-skin extract. Therefore, the use of ASE and PEF can be considered as useful strategies to recover antimicrobial, prebiotic and anti-inflammatory extracts from rainbow trout and sole side streams although it is necessary to evaluate the one by one each specific side stream.

Kiwiberry is a nutritive fruit produced by Actinidia arguta vine (Pinto, Delerue-Matos & Rodrigues, 2020). During its production and harvesting, different by-products, such as leaves, are generated (Pinto et al., 2020). These by-products are enriched in bioactive compounds, enabling its recovery and reuse (Pinto et al., 2020). The objective of this study was to evaluate the antioxidant, radical scavenging, and cell viability effects of A. arguta leaves extracts at different temperatures (110-160°C), applying subcritical water extraction (SWE), a sustainable extractive methodology. The total phenolic content (TPC), total flavonoid content (TFC) and antiradical activity (DPPH and ABTS assays) were evaluated as well as the scavenging activity against superoxide (O₂·^-), hypochlorous acid (HOCl) and peroxyl radical (ROO·). Also, cell viability assays on HT29-MTX and Caco-2 cell lines were performed. The extract obtained at 123°C achieved the best results in all assays (TPC = 109.72 mg GAE/g dw; TFC = 53.11 mg CE/g dw; DPPH = 497.13 µg/mL; O₂·^- = 335.23 µg/mL; HOCl = 17.06 µg/mL; S_sample/S_Trolox = 0.15), except in ABTS assay. TPC, TFC and HOCl values were better than those obtained by different authors employing other extractive methods (Ravipati et al., 2012; Marangi et al., 2018; Almeida et al., 2018). The cell viability assays allow to observe that the viability was not affected by the extracts at the highest tested concentration (1000 µg/mL) for HT29-MTX cells. Relatively to Caco-2 cells, the extract at 160°C displayed viabilities of 80.93%, at concentrations of 10 µg/mL. Therefore, temperature probably influences the content of the extracted bioactive compounds, leading to the obtained results. These results highlight the potentialities of A. arguta leaves for pharmaceutical, food or cosmetic applications.

References:

Almeida, D., Pinto, D., Santos, J., Vinha, A. F., Palmeira, J., Ferreira, H. N., Rodrigues, F., Oliveira, M. B. P. P. (2018). Hardy kiwifruit leaves (Actinidia arguta): An extraordinary source of value-added compounds for food industry. Food Chemistry, 259, 113–121. https://doi.org/10.1016/j.foodchem.2018.03.113.

Marangi, F., Pinto, D., de Francisco, L., Alves, R. C., Puga, H., Sut, S., Dall'Acqua, S., Rodrigues, F., Oliveira, M. B. P. P. (2018) Hardy kiwi leaves extracted by multi-frequency multimode modulated technology: A sustainable and promising by-product for industry. Food Research International 112, 184–191. https://doi.org/10.1016/j.foodres.2018.06.029

Pinto, D., Delerue-Matos, C., & Rodrigues, F. (2020). Bioactivity, phytochemical profile and pro-healthy properties of Actinidia arguta: A review. Food Research International, 136, Article 109449. https://doi.org/10.1016/j.foodres.2020.109449.

Ravipati, A. S., Zhang, L., Koyyalamudi, S. R., Jeong, S. C., Reddy, N., Bartlett, J., Smith, P. T., Shanmugam, K., Münch, G., Wu, M. J., Satyanarayanan, M., Vysetti, B. (2012). Antioxidant and anti-inflammatory activities of selected Chinese medicinal plants and their relation with antioxidant content. BMC Complementary and Alternative Medicine, 12(1), 173. https://doi.org/10.1186/1472-6882-12-173