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Fruit and vegetable industries face a major environmental challenge with food loss and waste. Broccoli stems, comprising 38% of the plant's total weight, are usually discarded by the industry producing fourth-range and ready-to-use products, despite being rich in antioxidants, vitamins, fiber, carotenoids, phenolic compounds, and glucosinolates. Addressing the challenge of reducing waste in this sector includes the production of stable and nutrient-concentrated powders, which can be consumed directly or used as ingredients in functional food formulation. This study investigated fermentation with lactic acid bacteria (Limosilactobacillus reuteri, Lactiplantibacillus plantarum, and Lactobacillus salivarius) as a pretreatment for enhancing antioxidant and probiotic potential in broccoli stem powders. Results showed maximum counts 24 h after inoculation, and no effect of the previous disruption intensity on microbial growth was observed. Fermenting broccoli stems for 24 h with the three microbial strains led to a significant increase in total phenols and flavonoids but to a general reduction in the samples' capacity to scavenge DPPH and ABTS free radicals. Overall, ground broccoli stems exhibited the most favorable antioxidant properties following the 24 h fermentation step. The subsequent freeze-drying and final grinding had minimal impact on the microbial population but significantly enhanced the extractability of the antioxidant compounds. This study offers a valuable reference for researchers and stakeholders exploring the development of new products and innovations from vegetable waste.

Fortification of bakery products with plant-based functional ingredients has gained interest in recent years. Low-cost fruit and vegetable waste has been proposed to replace wheat flour, but less research has been conducted on gluten-free flours. Rice is generally accepted as a gluten-free alternative to wheat flour but is poor in bioactive constituents; thus, the addition of vegetable-based functional ingredients could improve the nutritive value of gluten-free products. In the present work, IV-range carrot waste powder (CP) was incorporated into rice-based gluten-free muffin formulations in different proportions (5, 10, 20, and 30% w/w). The impact of CP addition on physicochemical and antioxidant properties was evaluated in flour blends, doughs, and baked products. Products were also evaluated in terms of water activity, hardness, and colour before and after a one-week storage period under fridge conditions. The results showed that water and oil absorption capacities increased in flour blends with CP addition, whereas the pasting properties of flour blends were affected when adding CP. Rheological measurements revealed an increase of G’ and G’’ modulus values with CP addition. Colour was also significantly modified by CP addition, since CP provided an orangish and brownish colour, but also due to intensified Maillard reactions during baking. Muffin hardness was reduced in enriched formulations compared to control ones, which was attributed to the fibre being incorporated with CP. It was confirmed that CP addition improved the antioxidant properties of both flour blends and muffins, with the higher the replacement, the better the antioxidant properties. The quality of gluten-free muffins was hindered after one week stored under cold conditions, so that colour was affected, hardness increased, and the antioxidant properties diminished. In conclusion, this work presents an interesting approach for the use of carrot waste flour as a functional food ingredient to improve the nutritional value of new gluten-free rice-based muffins, thus contributing to the circularity of food systems and to the development of healthier and more sustainable diets.

Almond bagasse resulting after the production of almond-based drinks represents a promising by-product with potential for use as a functional ingredient. To facilitate its utilization, the stability of this material can be achieved through dehydration processes such as hot air drying or freeze-drying. Nevertheless, owing to its high fat content, almond bagasse is prone to lipid oxidation, which could result in undesirable quality. Therefore, the objective of this work was to assess the impact of dehydration (by hot air drying at 60 and 70 °C and by freeze-drying) and storage (at room temperature and in accelerated conditions) on the functional quality and stability of almond bagasse powder. Throughout the dehydration process, it was observed that antioxidant compounds were preserved without significant differences among dehydration treatments. These compounds increased over the storage period, especially in the samples treated with hot air. Regarding antiradical capacity, the hot-air-dried samples showed higher values than the freeze-dried ones, although in all cases, it increased during storage. For total phenols in samples air-dried at 70 °C, increases of more than 50% were observed. The acidity and peroxide index were increased in the extended storage period, although they did not reach critical values. Samples stored for 180 days showed peroxide values ranging from 10 to 12.8 meq O2/kg dry matter for samples stored at room temperature and from 14.7 to 23 meq O2/kg dry matter for samples subjected to accelerated storage.

The recovery of food by-products and waste is an issue of universal concern, as every year the food industry generates a huge amount of waste and by-products from a variety of sources [...]

Valorisation of fruit and vegetable wastes by transforming residues and discards into functional powdered ingredients has gained interest in recent years. Moreover, fermentation has been recalled as an ancient technology available to increase the nutritional value of foods. In the present work, the impact of pretreatments (disruption and fermentation) on drying kinetics and functional properties of powdered broccoli stems was studied. Broccoli stems fermented with Lactiplantibacillus plantarum and non-fermented broccoli stems were freeze-dried and air-dried at different temperatures. Drying kinetics were obtained and fitted to several thin layer mathematical models. Powders were characterized in terms of physicochemical and antioxidant properties, as well as of probiotic potential. Fermentation promoted faster drying rates and increased phenols and flavonoids retention. Increasing drying temperature shortened the process and increased powders’ antioxidant activity. Among the models applied, Page resulted in the best fit for all samples. Microbial survival was favoured by lower drying temperatures (air-drying at 50 °C and freeze-drying). Fermentation and drying conditions were proved to determine both drying behaviour and powders’ properties.

The presence of components of nutritional interest makes fresh almond bagasse an interesting by-product for obtaining functional ingredients. Stabilization through a dehydration process is an interesting option for its integral use, ensuring its conservation and management. Subsequently, it can be turned into powder, facilitating its use as an ingredient. The aim of this paper was to determine the effects of hot air drying at 60 and 70 °C and lyophilization on the release of phenolic components and antiradical capacity in in vitro gastrointestinal digestion and colonic fermentation, as well as on growing microbiota composition by applying high throughput sequencing. The novelty of this study lies in this holistic approach; considering both technological and physiological aspects related to gastrointestinal digestion and colonic fermentation will provide the best conditions for functional foods. The results obtained showed that lyophilization provides a powder with a total phenol content and antiradical capacity higher than hot air drying. Furthermore, in dehydrated samples, both in vitro digestion and colonic fermentation revealed a phenol content and anti-radical capacity superior to those existing in undigested products. In addition, after colonic fermentation, beneficial bacteria species have been identified. Obtaining powders from almond bagasse is presented as an interesting opportunity for the valorization of this by-product.

Daucus carota L. is an important food crop utilized worldwide and a rich source of bioactive compounds. Carrot processing generates residues which are discarded or underused, for which using them as a source for obtaining new ingredients or products is an opportunity for the development of healthier and more sustainable diets. In the present study, the impact of different milling and drying procedures and in vitro digestion on the functional properties of carrot waste powders was evaluated. Carrot waste was transformed into powders by disruption (grinding vs. chopping), drying (freeze-drying or air-drying at 60 or 70 °C) and final milling. Powders were characterized in terms of physicochemical properties (water activity, moisture content, total soluble solids and particle size) nutraceuticals (total phenol content, total flavonoid content antioxidant activity by DPPH and ABTS methods, as well as carotenoid content (α-carotene, β-carotene, lutein, lycopene). Antioxidants and carotenoid content during in vitro gastrointestinal digestion were also evaluated; the latter in different matrices (directly, in water, in oil, and in oil-in-water emulsion). Processing allowed to reduce water activity of samples and obtain powders rich in antioxidant compounds and carotenoids. Both disruption and drying had a significant impact on powders’ properties freeze-drying led to finer powders with higher carotenoid content but lower antioxidant values, whereas air-drying implied chopped air-dried powders exhibited higher phenols content and improved antioxidant activity. Simulated in vitro digestion studies revealed that digestion helps release bioactive compounds which are bound to the powder structure. The solubilization of carotenoids in oil was low, but fat co-ingestion notably increased their recovery. According to the results, carrot waste powders containing bioactive compounds could be proposed as functional ingredients to increase the nutritional value of foods, thus contributing to the concepts of more sustainable food systems and sustainable healthy diets.

Fermentation of fruit juices with lactic acid bacteria enhances their antioxidant properties to a different extent depending on the microbial strain and the growing media composition, which can be modified by adding certain ingredients or applying a homogenization step. This study analyzed the effect of trehalose addition (10%, w/w) and homogenization at 100 MPa before or after Lactobacillus salivarius spp. salivarius CECT 4063 inoculation on the antioxidant profile and the microbiological properties of commercial clementine juice during 96 h fermentation. Antioxidant properties and viable cell count of 24 h-fermented juices during refrigerated storage (30 days at 4 °C) were also evaluated. Fermentation over 24 h reduced the microbial population and antioxidant content of clementine juice. Homogenizing the juice before inoculation enhanced the microbial growth but favored antioxidant degradation. Adding trehalose (10%, w/w) to the juice formulation and/or homogenizing at the fermented juice at 100 MPa for 24 h had a negative impact on viable counts and did not improve the microbial adhesion to intestinal mucosa. However, both techniques prevented antioxidant oxidation and cell decay during the storage of fermented juice under refrigeration, which should not last more than 15 days.

Reintroducing waste products into the food chain, thus contributing to circular economy, is a key goal towards sustainable food systems. Fruit and vegetable processing generates large amounts of residual organic matter, rich in bioactive compounds. In Brassicaceae, glucosinolates are present as secondary metabolites involved in the biotic stress response. They are hydrolysed by the enzyme myrosinase when plant tissue is damaged, releasing new products (isothiocyanates) of great interest to human health. In this work, the process for obtaining powdered products from broccoli and white cabbage by-products, to be used as food ingredients, was developed. Residues produced during primary processing of these vegetables were transformed into powders by a process consisting of disruption (chopping or grinding), drying (hot-air drying at 50, 60 or 70 °C, or freeze drying) and final milling. The impact of processing on powders’ physicochemical and functional properties was assessed in terms of their physicochemical, technological and antioxidant properties. The matrix response to drying conditions (drying kinetics), as well as the isothiocyanate (sulforaphane) content of the powders obtained were also evaluated. The different combinations applied produced powdered products, the properties of which were determined by the techniques and conditions used. Freeze drying better preserved the characteristics of the raw materials; nevertheless, antioxidant characteristics were favoured by air drying at higher temperatures and by applying a lower intensity of disruption prior to drying. Sulforaphane was identified in all samples, although processing implied a reduction in this bioactive compound. The results of the present work suggest Brassica residues may be transformed into powdered ingredients that might be used to provide additional nutritional value while contributing to sustainable development.

Food science and technology plays a very important role in designing and developing new foods, and in improving the safety, nutritional and organoleptic quality of processed foods [...]

Food waste is a worldwide concern as it represents a constant threat to the environment and a serious operational problem for the food industry. The by-products of fruits and vegetables being a valuable source of bioactive compounds have the potential to be reused and reintroduced in the agri-food chain. This circular approach contributes to a sustainable production system. In this context, a collaborative project with the primary sector for the integral valorization of the waste generated in the fresh-processing vegetable lines of an agricultural cooperative is currently being developed, particularly focused on cabbage, carrot, celery, and leek. The objective of this project is to transform vegetable wastes into functional powdered ingredients and be able to use them in food formulations in order to improve the nutritional profile of foods, contributing to the development of sustainable healthy diets. Through an exhaustive bibliographic review, this research studies the influence of pretreatments, drying and in vitro digestion on the bioactive compounds of vegetable residues, with the aim of identifying the appropriate production parameters to achieve an adequate functional and physicochemical profile of the final powders.

The aim of this study was to evaluate the use of lulo juice as substrate for producing a potentially probiotic beverage with Lactobacillus reuteri CECT 925. Lulo juices at two pH levels and two levels of HPH treatment have been considered to evaluate the effect of these variables on Lactobacillus reuteri CECT 925 growth, physicochemical and antioxidant properties, and the resistance of microbial cells to gastrointestinal digestion in vitro. Regarding the growth of Lactobacillus reuteri CECT 925, it was mainly affected by the pH of the medium, the rectified juice at pH 5.5 being the most appropriated one. The growth of Lactobacillus reuteri CECT 925 mainly increased the antiradical capacity of the juices. In general, Lactobacillus reuteri CECT 925 showed good resistance to in vitro gastrointestinal digestion conditions, reaching levels above 107 CFU/mL in all cases. The highest resistance was observed in the juice treated at 150 MPa followed by the juice homogenized at 100 MPa.

To benefit the health of consumers, bioactive compounds must reach an adequate concentration at the end of the digestive process. This involves both an effective release from the food matrix where they are contained and a high resistance to exposure to gastrointestinal conditions. Accordingly, this study evaluates the impact of trehalose addition (10% w/w) and homogenization (100 MPa), together with the structural changes induced in vacuum impregnated apple slices (VI) by air-drying (AD) and freeze-drying (FD), on Lactobacillus salivarius spp. salivarius (CECT 4063) survival and the bioaccessibility of antioxidants during in vitro digestion. Vacuum impregnated apple slices conferred maximum protection to the lactobacillus strain during its passage through the gastrointestinal tract, whereas drying with air reduced the final content of the living cells to values below 10 cfu/g. The bioaccessibility of antioxidants also reached the highest values in the VI samples, in which the release of both the total phenols and total flavonoids to the liquid phase increased with in vitro digestion. The addition of trehalose and homogenization at 100 MPa increased the total bioaccessibility of antioxidants in FD and AD apples and the total bioaccessibility of flavonoids in the VI samples. Homogenizing at 100 MPa also increased the survival of L. salivarius during in vitro digestion in FD samples.

Lulo (Solanum quitoense Lam.) is a Colombian fruit that is mostly used in the preparation of homemade juice as well as natural remedy for hypertension. The aim of this study was to determine physicochemical and antioxidant properties (antioxidant capacity, total phenols, flavonoids and spermidine content, and polyphenolic compounds profile by liquid chromatography—mass spectrometry (LC-MS)) of the lulo fruit and its juice. Additionally, vacuum impregnation (VI) properties of the fruit and the effect of high homogenization pressure (50, 100, and 150 MPa) on the juice properties were studied. The results revealed a good availability and impregnation capacity of the pores in fruits with similar maturity index. The main differences observed between the juice and fruit derive from removing solids and bioactive components in the filtering operation. However, the effect of high-pressure homogenization (HPH) on particle size and bioactive compounds increases the antiradical capacity of the juice and the diversity in polyphenolics when increasing the homogenization pressure.

Interest in high homogenization pressure technology has grown over the years. It is a green technology with low energy consumption that does not generate high CO2 emissions or polluting effluents. Its main food applications derive from its effect on particle size, causing a more homogeneous distribution of fluid elements (particles, globules, droplets, aggregates, etc.) and favoring the release of intracellular components, and from its effect on the structure and configuration of chemical components such as polyphenols and macromolecules such as carbohydrates (fibers) and proteins (also microorganisms and enzymes). The challenges of the 21st century are leading the processed food industry towards the creation of food of high nutritional quality and the use of waste to obtain ingredients with specific properties. For this purpose, soft and nonthermal technologies such as high pressure homogenization have huge potential. The objective of this work is to review how the need to combine safety, functionality and sustainability in the food industry has conditioned the application of high-pressure homogenization technology in the last decade.

Survival of probiotic microorganisms in dried foods is optimal for water activity (aw) values between 0.1 and 0.3. Encapsulating and adding low-molecular weight additives can enhance probiotic viability in intermediate aw food products, but the effectiveness of sub-lethal homogenization is still not proven. This study evaluates the effect of 10% (w/w) trehalose addition and/or 100 MPa homogenization on Lactobacillus salivarius CECT 4063 counts and antioxidant properties of apple slices dried to different water activity values (freeze-drying to a aw of 0.25 and air-drying at 40 °C to a aw of 0.35 and 0.45) during four-week storage. Optical and mechanical properties of dried samples were also analyzed. Freeze-drying had the least effect on the microbial counts and air drying at 40 °C to a aw of 0.35 had the greatest effect. Antioxidant properties improved with drying, especially with convective drying. Decreases in both microbial and antioxidant content during storage were favored in samples with higher water activity values. Adding trehalose improved cell survival during storage in samples with a water activity of 0.35, but 100 MPa homogenization increased the loss of viability in all cases. Air-dried samples became more translucent and reddish, rather rubbery and less crispy than freeze-dried ones.

The stabilization of fruit bagasse by drying and milling technology is a valuable processing technology to improve its durability and preserve its valuable biologically active components. The objective of this study was to evaluate the effect of lyophilization and air temperature (60 °C and 70 °C) in hot air-drying as well as grinding conditions (coarse or fine granulometry) on physico-chemical properties; water interaction capacity; antioxidant properties; and carotenoid content of powdered lulo bagasse. Air-drying kinetics at 60 °C and 70 °C and sorption isotherms at 20 °C were also determined. Results showed that drying conditions influence antioxidant properties and carotenoid content while granulometry slightly influenced fiber and water interaction properties. Fiber content was near 50% and carotenoid content was higher than 60 µg/g dry matter in lyophilized powder. This β-carotene content is comparable to that provided by carrot juice. Air-drying at 60 °C only reduced carotenoids content by 10%.

In a new probiotic food, besides adequate physicochemical properties, it is necessary to ensure a minimum probiotic content after processing, storage, and throughout gastrointestinal (GI) digestion. The aim of this work was to study the effect of hot air drying/freeze drying processes, encapsulation, and storage on the probiotic survival and in vitro digestion resistance of Lactobacillus salivarius spp. salivarius included into an apple matrix. The physicochemical properties of the food products developed were also evaluated. Although freeze drying processing provided samples with better texture and color, the probiotic content and its resistance to gastrointestinal digestion and storage were higher in hot air dried samples. Non-encapsulated microorganisms in hot air dried apples showed a 79.7% of survival rate versus 40% of the other samples after 28 days of storage. The resistance of encapsulated microorganisms to in vitro digestion was significantly higher (p ≤ 0.05) in hot air dried samples, showing survival rates of 50–89% at the last stage of digestion depending on storage time. In freeze dried samples, encapsulated microorganisms showed a survival rate of 16–47% at the end of digestion. The different characteristics of the food matrix after both processes had a significant effect on the probiotic survival after the GI digestion. Documented physiological and molecular mechanisms involved in the stress response of probiotic cells would explain these results.

Background: A favorable effect over development of degenerative diseases is derived of an adecuate intake of fruit and vegetables, mainly due to their antioxidant compounds Objectives: The goal of this study was to test the effect in vivo over oxidant status and inflammation in obese children of a novel food product made of dried apples enriched with mandarin juice by vacuum impregnation. Methods: A four-week intervention study was conducted in 41 obese children (> 2 standard deviation score-body mass index). Participants were instructed to follow their usual diet supplemented with 40 g/day of the developed product. Anthropometric parameters were determined including body mass index, waist circumference and estimations of body fat percentage using bioelectrical impedance. Dietary intake was assessed by questionnaire. Metabolic risk factors (blood pressure, lipid profile, glucose and insulin resistance) were recorded. To determine oxidant status, plasma total antioxidant capacity and 8-hydroxydeoxyguanosine, as marker of oxidative damage to DNA, were investigated. High-sensitive C-reactive protein, tumor necrosis factor-α, and interleukins 6 and 1-α were measured as inflammatory markers. Measurements were collected at baseline and at the end of the intervention period. Results: Significant improvement in systolic blood pressure and lipid profile after intervention period was noted. A significant increase in the antioxidant capacity of plasma (ABTS and FRAP assays) and reductions in DNA oxidative damage and inflammatory markers were also found. Conclusion: Overall, adding the product to the diet contributes to ameliorate oxidant and inflammatory status in obese children and several risk factors for atherosclerosis.

An important issue related with functional foods development is the stability of physiologically active compounds. For example vitamins, minerals, probiotic bacteria are very sensitive to the technological processes involved in their obtention. The objective of this paper is to evaluate the viability of a probiotic strain (Lactobacillus rhamnosus) inside a food matrix (Granny smith apple) and physical parameters such as color (L* a* b*) of vacuum impregnated apple cylinders during a refrigerated and frozen storage. The results show that the viable probiotic bacteria inside food matrix maintain the minimal value to be considered as probiotic functional food (10(6) CFU/g), and the color parameters which are critical in refrigerated samples during their storage.Un importante tema relacionado con el desarrollo de alimentos funcionales es la estabilidad de los componentes fisiológicamente activos como vitaminas, minerales, bacterias probióticas y otros, los cuales pueden ser muy sensibles al proceso tecnológico de obtención. El objetivo de este trabajo es evaluar la viabilidad de una cepa probiótica (Lactobacillus rhamnosus) en el interior de una matriz alimentaria (manzana Granny smith) y los parámetros de color (L* a* b*) en cilindros de manzana impregnados al vacío durante el almacenamiento bajo refrigeración y congelación. Los resultados muestran una viabilidad de la bacteria probiótica en el interior de la matriz alimentaria, manteniendo los valores mínimos para ser considerados como alimentos funcionales probióticos (10(6) UFC/g) y los parámetros de color son críticos en las muestras refrigeradas durante el almacenamiento.