Vera Lavelli

Effluents generated in the food and beverage industry typically contain elevated concentrations of organic carbon sources and inorganic nutrients, representing a significant environmental burden as global food demand continues to rise. Owing to their capacity to effectively assimilate carbon and nutrients while simultaneously generating biomass with potential valorization pathways, Chlorella spp. offers a dual benefit of contaminant removal and resource recovery. However, existing algal studies remain predominantly at the laboratory scale, and their competitive advantages have not been demonstrated for full-scale implementation. Kinetic modelling represents an essential tool to elucidate algal growth behavior, optimize operational conditions, and predict performance of algal systems for accurate scale-up, but limited studies are available to comprehensively review kinetic models of Chlorella spp. In this review, kinetic models were synthesized, including sigmoidal growth models (Gompertz, logistic, and Verhulst), single-factor and inhibition models (Monod and Andrews), light-dependent photobioreactor models (Huisman), multifactor and interaction models for co-cultures (Lotka–Volterra). Kinetic parameters from these models were compiled to support consistent projections from lab-scale to industrial-scale systems, enabling future techno-economic analysis and life-cycle assessment of algal systems. Other emerging technologies, such as artificial intelligence and machine learning approaches, were also reviewed. The review also identified benchmark processes and outlined a decision tree for developing strategies to enhance resource recovery and phycoremediation performance. Finally, key research needs have been highlighted to guide future work in the field.

Food waste in school canteens is widely recognized as a significant issue because of its economic consequences, environmental impact, and implications for children’s health. Previous studies have used robust methods to quantify this problem and assess mitigation strategies. This case study of primary school children (6–11 years) used a child-driven approach to measure plate waste and explore reasons for uneaten food and concern about waste. The results indicated that a group of volunteer children (n = 104) directly involved in the assessment were able to evaluate their peers’ food waste, obtaining estimates comparable to those reported in previous studies (mean: 108.4 g per child). The students for whom food waste was measured (n = 443) took part in interviews and proved to be active participants capable of evaluating their own context, although their level of engagement could be further strengthened. Among children who reported leaving food uneaten, a substantial proportion provided specific reasons; nevertheless, generic explanations accounted for 26% of responses for the first course and 35% for the second. Approximately 78.5% of the children demonstrated a high level of sensitivity to food waste, recognizing its direct effects (wasting their parents’ money), indirect effects (waste in a broader sense), and social effects (world hunger/poverty). Establishing a baseline for children’s sensitivity to their own food waste is therefore needed, as it could serve as an indicator of both the urgency and the effectiveness of educational interventions.

Pod is the major solid waste from bean processing, and its accumulation is expected to increase in the coming years due to the increases in pulse consumption. This study aimed to investigate (a) the efficacy ultrasound (US)-assisted extraction of polyphenols from bean pod; (b) their solubilization rate constants and effective diffusivities (De), which are relevant parameters for scaling-up the process; and (c) the encapsulation efficiencies of the recovered phenolic compounds in hydrogel microbeads. Extracts were obtained either in water with US assistance (50–350 W·L⁻¹) at 30 °C; in water at 30, 45 and 60 °C; or in water/ethanol mixtures at room temperature. Extracts were analyzed using HPLC with diode array and fluorometric detectors. The extract from US-assisted extraction, selected as the most promising treatment among those evaluated, was then encapsulated in alginate or alginate/chitosan microbeads. Changes in the solubilization rate constants (from 0.097 to 0.480 min⁻¹) and De (from 3.4·10⁻¹¹ to 4.6·10⁻⁹ m²·s⁻¹) were observed upon the application of US. Increasing the acoustic energy density was more effective at accelerating solubilization than either increasing the temperature or using ethanol as a cosolvent. Polyphenols were better encapsulated in an alginate/chitosan matrix than in alginate alone, achieving 71% recovery of ferric reducing antioxidant power and 69% recovery of 2,2-diphenyl-1-picrylhydrazyl radical-scavenging activity. The cost-effective alginate/chitosan matrix entrapping of pod polyphenols is potentially useful in various food applications.

The increase in the incidence of hyperglycemia and diabetes poses the challenge of finding cost-effective natural inhibitors of starch digestion enzymes. Among natural compounds, phenolics have been considered as promising candidates. The aims of this study were as follows: (a) to investigate the effectiveness of the inhibition of different winemaking byproducts towards intestinal brush border α-glucosidase and pancreatic α-amylase in vitro; (b) to calculate an efficacy index relative to the standard acarbose for the phenolic pool of winemaking byproducts, as well as for isolated phenolic compounds and for the phenolic pools of different plants studied in the literature, in order to rank winemaking byproducts with respect to the reference drug and other natural alternatives. Among winemaking byproducts, red grape skins showed the highest inhibitory activities towards both α-glucosidase and α-amylase, which were, on average, 4.9 and 2.6 µg acarbose equivalents/µg total phenolics (µg Ac eq/µg GAE), respectively. A correlation was observed between the total phenolic contents of red grape skins and their inhibitory effectiveness, which is useful for standardizing the efficacy of phenolic extracts obtained from different winemaking processes. In general, the inhibitory activity of the phenolic pool of grape skins was higher than those of isolated phenolic compounds, namely anthocyanins and monomeric and polymeric flavanols and flavonols, probably due to synergistic effects among compounds. Hence, bioactive phenolic fractions could be produced with the focus on functionality rather than purity, in line with the principles of sustainable processing. Based on the efficacy index developed to compare different phenolic compounds and phenolic-rich plants studied in the literature as starch digestion enzyme inhibitors, red grape skins proved to be cost-effective candidates.

Raisin can be used a substitution of artificially sweetened snacks/ingredients, in order to counteract the increasing consumption of sugar-added foods, which is associated to adverse health effects. The aim of this study was to investigate the phenolic content, reducing capacity and antiglycation activities of traditional, sun-dried raisin samples obtained from six Tunisian varieties. Total phenolics were determined by the Folin Ciocalteu assay, proanthocyanidins by depolymerisation with n-butanol/HCl, monomeric and dimeric flavanols, flavonols and anthocyanins by HPLC with diode array and fluorimetric detectors. The reducing capacity was assessed by ferric ion reducing antioxidant power assay (FRAP) and anti-glycation activity by the bovine serum albumin/fructose (BSA/FRU) and BSA/methyglyoxal (BSA/MGO) model systems. Results showed a remarkable biodiversity in phenolic contents and profile among raisin samples. The reducing capacity ranged between 43.8 and 97.8 mmol Fe(II) eq/kg d.w. Raisin samples inhibited protein glycation in the in vitro model systems, which simulate the early and intermediate steps of the formation of advanced-glycation end-products occurring in vivo and leading to cell damage. The anti-glycation effectiveness in the BSA/FRU and BSA/MGO model systems was in the range 48–176 and 9.6–20.5 mmol catechin eq./kg d.w., respectively and was generally comparable or, for some raisin varieties higher than that of well-known antiglycation agents. These results support the promising role of raisin as a functional food/ingredient targeting the inhibition of glycoxidative damage.

The increase in the incidence of hyperglycemia and diabetes poses the challenge to search cost-effective natural inhibitors of starch digestion enzymes. Among natural compounds, phenolics have been considered as promising candidates. The aims of this study were: a) to investigate if winemaking byproducts are effective as inhibitors of the intestinal brush border alpha-glucosidase and the pancreatic alpha-amylase in vitro; b) to calculate an efficacy index for their phenolic pool, despite their variability due to grape cultivar and winemaking process; c) to compare winemaking byproducts’ efficacy with those of other plants. Winemaking by-products were characterized for the contents of total phenolics, flavanols, flavonols and anthocyanins, as well as the inhibitory activity towards the intestinal brush border alpha-glucosidase and pancreatic alpha-amylase. The inhibition towards alpha-glucosidase resulted to be on average 2.29 and 4.89 µg acarbose equivalents/µg total phenolics (µg Ac eq/µg GAE) for white and red grape skins, respec-tively. The inhibition towards alpha-amylase was 0.5 and 1.6 µg Ac eq/µg GAE for white and red grape skins, respectively. The inhibitory activity of the phenolic pool of red grape skins was higher than those of isolated phenolic compounds, probably due to synergistic effects among compounds. Hence, bioactive phenolic fractions could be produced with the focus on functionality rather than purity, in line with the principles of sustainable processing. A correlation was observed between the total phenolic contents of red grape skins and their inhibitory effectiveness, which is useful to standardize the efficacy of phenolic extracts. Compared to other plants reported in the literature red grape skins resulted to be cost-effective sources of starch digestion enzyme inhibitors.

The approach to ensure food safety (FS) has evolved, including the concept of FS culture, which has been shaped by both the legislation and the scientific literature. In this study, two companies that produce foods associated with potential risks of cross-contamination (gluten-free foods and frozen pastry, respectively) and are certified according to international voluntary FS standards, such as the British Retail Council Global Standard (BRC) and the International Featured Standards Food Version (IFS), were investigated to assess: (a) if the assessment of FS culture’s pillars can uncover unexpected critical areas; (b) if the scores of the FS culture’s pillars are related to personal traits, namely, age, seniority in the company and locus of control orientation, i.e., the beliefs that an event is the result of external factors (luck, destiny or superior beings), or the result of internal factors (human behavior). Questionnaires for the survey and the scoring system applied were selected from the literature. Results showed that all food handlers had an optimistic bias, which paradoxically could be the consequence of the rigorous application of hygienic procedures. The younger food handlers had significantly (p < 0.05) lower commitment than the older ones. Moreover, the segment of food handlers having an external locus orientation demonstrated weaker normative beliefs than those having an internal locus of control orientation. Results showed that the FS culture survey, which is related to the shared FS culture, could disclose unknown weakness in third-party certified companies, even if the well implemented principles of voluntary FS standards are aligned with the FS-culture pillars. Moreover, the segmentation of food handlers according to their age and the locus of control assessment could provide additional information on the individual orientation toward FS behavior. Hence these tools could assist the leaders in the management of the dynamic nature of human capital.

Ultrasound (US)-assisted soaking combined with fortification with red grape skin (GS) phenolics was applied on two Phaseolus varieties, namely White Kidney Bean (WKB) and Cranberry Bean (CB), before heat treatment. The aims were to investigate: (a) the effect of US application on the kinetic of hydration; (b) the extent of absorption of different phenolic classes of GS into the beans and the resulting effect on antioxidant activity; (c) the effects of heat treatment on the phenolic fraction and antioxidant activity of GS extract- and water-soaked beans. US fastened the soaking step of both WKB and CB beans, which showed the sigmoidal and the downward concave shape hydration curves, respectively. Anthocyanins, flavonols, flavanol and phenolic acids levels increased with GS soaking, but US application was effective only for increasing the level of flavonols, while it favored the loss of endogenous phenolic acids and it did not affect the uptake of anthocyanins and flavanols. Heat treatment decreased the levels of most of phenolic compounds, but increased the levels of monomeric flavanols. Overall, the antioxidant activity was 40% higher in WKB and 53% higher in CB upon GS-fortification than in the control beans, despite the effects of heating. This fortification strategy could be applied for value addition of varieties low in phenolics or as a pre-treatment before intensive processing.

Encapsulation of antioxidants in hydrogels, i.e., three-dimensional networks that retain a significant fraction of water, is a strategy to increase their stability and bioaccessibility. In fact, low oxygen diffusivity in the viscous gelled phase decreases the rate of oxidation. Moreover, some hydrocolloids such as alginate and whey proteins provide a pH-dependent dissolution mechanism, allowing the retention of encapsulated compounds in the gastric environment and their release in the intestine, where they can be absorbed. This paper reviews the information on alginate-whey protein interactions and on the strategies to use binary mixtures of these polymers for antioxidant encapsulation. Results showed that alginate and whey proteins strongly interact, forming hydrogels that can be modulated by alginate molecular mass, mannuronic acid: guluronic acid ratio, pH, Ca²⁺ or transglutaminase addition. Hydrogels of alginate and whey proteins, in the forms of beads, microparticles, microcapsules, and nanocapsules, generally provide better encapsulation efficiency and release properties for antioxidants with respect to the hydrogel of alginate alone. The main challenges for future studies are to extend knowledge on the interactions among three components, namely alginate, whey proteins, and the encapsulated bioactive compounds, and to investigate the stability of these structures under food processing conditions. This knowledge will represent the rationale basis for the development of structures that can be tailored to specific food applications.