Food Processing By-products Research Articles

FEED LYSIN. MEANING AND SYNTHESIS

The intensification of animal husbandry depends on the full feeding of farm animals, which provides for the content of the most important nutrients and biologically active substances in the feed. In order to obtain the necessary amount of high-quality livestock products, to ensure high reproductive capacity of animals, specialists develop animal feeding rations taking into account minimum feed costs. Providing farm animals with fodder protein is one of the important tasks of agriculture and enterprises that produce protein fodder or obtain it in the form of by-products. The use of by-products of food processing is of great importance in animal feeding programs and also solves the problem of disposal of these by-products. The application of such solutions will allow to reduce the need of farms for fodder grain, fodder of animal origin and other expensive components used in feeding. Protein feeds of plant origin include sunflower processing products as the cheapest source of feed protein in Ukraine. The inferiority of the proteins of sunflower cake and meal should be compensated with synthetic amino acids. Lysine, as an essential amino acid, has a wide range of applications, covering various fields from medicine to the food industry and agricultural activities, in particular in the feed industry. Most of the produced lysine is used in the production of feed additives (for pigs and poultry), which significantly increase the nutritional value of vegetable feed with a low lysine content. The addition of lysine to compound feed improves protein digestibility by animals and reduces feed costs for the production of livestock products. Given the availability of lysine and taking into account livestock statistics, namely the increase in the number of pigs and the decrease in the number of cattle and poultry, industrial production of lysine as a feed additive for pigs is a promising direction. The main methods of lysine production are considered - chemical, chemical-enzymatic, biological and microbiological. The technology of each method is analyzed in detail, the advantages and disadvantages of different methods of obtaining lysine are given.

Rethinking Food Waste: Insights from the 2021 and 2022 RETASTE Conferences

The RETASTE Conference has established itself as a critical platform for advancing science and innovation on food waste management within the framework of circular economy practices. This editorial summarises the key themes and research presented at the first two RETASTE meetings, which focused on strategies such as the valorisation of food processing by-products, utilization of food waste for bioplastics, and development of waste-to-energy technologies. These studies demonstrate the potential to transform food waste from an environmental burden into valuable resources, thereby supporting both local and global sustainability objectives. The conference also highlighted the importance of integrating technology with policy and social aspects to drive transformation across the entire food system, while acknowledging the challenges that remain, including cultural, political, and administrative barriers that must be addressed for these innovations to be successfully scaled. The rebranding of the conference to “RETASTE: Rethink Food Resources, Losses, and Waste” signals a broader focus on the interconnectedness of food systems, emphasizing the need for continuous innovation and collaboration across all sectors. This editorial concludes that a holistic approach—combining technological advancements, social practices, and robust policy frameworks—is essential for effectively managing food waste and promoting sustainable food systems globally.

Isolation and Purifying of Xylooligosaccharides from Various Mongolian Food Processing By-Products

Xylooligosaccharides (XOS) are hemicellulose constituents that naturally occur in wheat bran peels and brewery-spent grain. XOS comprises two to six xylose residues connected by β-(1,4) linkages. These compounds are vulnerable to enzymatic breakdown by gut microorganisms. In this study, some industrial by-products, specifically wheat bran peels (WBP) and brewers’ spent grain (BSG), underwent treatment using microwave-facilitated enzymatic hydrolysis. The current study produced 8.1 g of purified dried XOS from 100 g of WBP material and 7.2 g of pure dried XOS from 100 g of BSG material. Singular microwave irradiation of WBP and BSG before enzymatic hydrolysis, along with a precisely determined enzyme-to-raw-material ratio of 0.25 g/100 g, resulted in optimal conditions. This approach significantly enhanced the efficacy of xylanases on both WBP and BSG. Results of our study proved that microwave assisted pretreatment improves the xylanase enzymatic hydrolysis which increase yield of XOS.

Physicochemical Properties of Isolated Proteins for Upcycling Food Processing By-products

Physicochemical Properties of Isolated Proteins for Upcycling Food Processing By-products

Transcriptome Analysis of Aureobasidium pullulans YQ65 Grown on Yeast Extract Peptone Glucose and Potato Dextrose Agar Media and Quantification of Their Effects on Pullulan Production.

Pullulan is a high-value polysaccharide produced through the fermentation of Aureobasidium pullulans. It has significant applications in the fields of food, medicine, environmental science, and packaging. However, the yield, molecular weight, and other characteristics of pullulan can vary depending on the fermentation substrate used. Therefore, it is crucial to analyze the underlying causes of these variations at the molecular level. In this study, we first investigated the morphological differences in A. pullulans YQ65 when cultured in YPD and PDA media. The results indicated that different culture media significantly influence the primary cell morphology of A. pullulans YQ65, which in turn affects the synthesis of secondary metabolites. Subsequently, we employed different culture media to ferment pullulan and examined the variations in pullulan yield, molecular weight, and biomass. Moreover, FTIR and thermodynamic stability tests were conducted to analyze the differences among pullulans across different culture media. Finally, transcriptome analysis revealed that A. pullulans YQ65, when cultured in YPD and PDA media, regulates its growth and metabolism through the expression of key genes that are involved in pathways such as the proteasome, oxidative phosphorylation, metabolism of various secondary metabolites, fatty acid anabolism, carbon metabolism, and amino acid metabolism. The transcriptome results were further validated by assessing the expression of specific genes. This study enhances the understanding of the fermentation differences observed with different substrates in A. pullulans and provides valuable insights for optimizing culture substrates. Additionally, it offers guidance for utilizing agricultural and forestry processing waste, as well as food processing by-products, to produce pullulan cost-effectively in the future.

Significantly improved co-extraction of hesperidin and narirutin from mandarin peel, a food processing by-product, based on statistical predictive models

Mandarin peel (MP) from food processing contains useful ingredients such as flavonoids, thus valorization strategies for MP are expected to be the first step in realizing a sustainable society. This study designed the co-extraction of two flavonoids (hesperidin and narirutin) from MP based on a multiple regression model with extraction temperature, time, and solid loading as the major variables. Numerical optimization determined that the optimal condition to maximize the extraction of both flavonoids was 60.0 °C, 100.9 min, and 95.7 g/L. Under this condition, the experimental results showed that the recovery of hesperidin and narirutin achieved 31.9 and 14.8 mg/g-biomass, respectively, which were in over 90% agreement with the predicted values. Total flavonoid content of MP extract was 81.9 mg/g-biomass, and antioxidant activity (ABTS EC50: 2.8 μg/mL) was similar to ascorbic acid. Previous studies have reported the identification of major flavonoids in MP, however, this is the first to achieve maximum recovery of two targeted flavonoids. In particular, the innovation of this study was the optimization of co-extraction, which demonstrated the high potential of MP extract as a natural antioxidant.

Effects of powderization of a granular diet on growth performance of the edible cricket, Teleogryllus occipitalis (Orthoptera: Gryllidae)

Abstract Farming edible crickets has environmental and nutritional benefits, as well as social benefits such as livelihood diversification. Commercial feeds for poultry and fish farming are often used to feed crickets, and in recent years, crop and food-processing by-products have also been used to improve sustainability. However, the design of feed for crickets has not been standardized. Here, we investigated growth and development of the Asian field cricket, Teleogryllus occipitalis (Audinet-Serville) (Orthoptera: Gryllidae), fed on different forms of the same diet. Body mass and the rate of development were significantly greater in crickets fed on millimetre-order granules than in crickets fed on micrometre-order powder. In addition, analysis of feeding behaviour revealed that crickets fed less frequently on the powdered diet than on the granulated diet. These results suggest that crickets have an avoidance behaviour towards fine particles, or that the granular form is easier for them to grasp and ingest than the powdery form, which may have contributed to growth performance. Simply feeding millimetre-order granules may contribute to the development of feed design for farming edible crickets.

Associations of Advanced Glycation End Products with Sleep Disorders in Chinese Adults.

Advanced glycation end products (AGEs), a group of food processing byproducts, have been implicated in the development of various diseases. However, the relationship between circulating AGEs and sleep disorders remains uncertain. This cross-sectional study elucidated the association of plasma AGEs with sleep disorders among 1732 Chinese adults who participated in the initial visit (2019-2020) of the Tongji-Shenzhen Cohort (TJSZC). Sleep behavior was assessed using self-reported questionnaires and precise accelerometers. Plasma levels of AGEs, including Nε-(Carboxymethyl)lysine (CML), Nε-(Carboxyethyl)lysine (CEL), and Nδ-(5-hydro-5-methyl-4-imidazolone-2-yl)-ornithine (MG-H1), were quantified by ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). In logistic regression, per IQR increment in individual AGEs was associated with an increased odds ratio of short sleep duration (CML: 1.11 [1.00, 1.23]; CEL: 1.16, [1.04, 1.30]), poor sleep quality (CML: 1.33 [1.10, 1.60]; CEL: 1.53, [1.17, 2.00]; MG-H1: 1.61 [1.25, 2.07]), excessive daytime sleepiness (CML: 1.33 [1.11, 1.60]; MG-H1: 1.39 [1.09, 1.77]), and insomnia (CML: 1.29 [1.05, 1.59]). Furthermore, in weighted quantile sum regression and Bayesian kernel machine regression analyses, elevated overall exposure levels of plasma AGEs were associated with an increased risk of sleep disorders, including short sleep duration, poor sleep quality, excessive daytime sleepiness, and insomnia, with CML being identified as the leading contributor. Insufficient vegetable intake and higher dietary fat intake was associated with an increase in plasma CEL. These findings support a significant association between plasma AGEs and sleep disorders, indicating that AGEs may adversely influence sleep health and reducing the intake of AGEs may facilitate preventing and ameliorating sleep disorders.

Synthesis of rice husk derived porous carbon as low-cost and high-performance electrode material for supercapacitors

Porous carbon electrode materials derived from agricultural by-products of food processing have attracted widespread interest. Rice husk (RH) is a promising raw material owing to its abundance and low price. In this study, a supercapacitor electrode was prepared by using recycled RH and secondarily activated with ZnCl2 to enhance its electrochemical energy storage performance. RH carbonized at the optimum temperature (i.e., 800 °C) was activated to synthesize RH-800-X (X = 1, 2, 3, 4, or 5, representing the mass ratio of ZnCl2 to RH-800). Sample RH-800-3 exhibited the highest specific surface area (1348.29 m2 g−1) and mesoporous pore volume (0.8375 cm3 g−1) among the samples. In a three-electrode system, the prepared electrodes delivered a high specific capacitance (242 F g−1 at 0.3 A g−1 in 6 M KOH solution). Furthermore, the capacitance retention of RH-800-3 remained at 99.9 % after 17,000 charge/discharge cycles. The results demonstrate the excellent capacitive behavior and superior electrochemical performance of RH-800-3. In addition, symmetrical capacitors prepared using RH-800-3 have an energy density of up to 101 Wh kg−1 at a power density of 900 W kg−1. Therefore, this study presents a simple and effective method for preparing a high-performance electrode material from biomass-derived porous carbon (i.e., recycled RH) and offers a new perspective for the efficient utilization of waste biomass resources.

Current Trends in Food Processing By-Products as Sources of High Value-Added Compounds in Food Fortification.

Along the food production chain of animal, fish, and vegetable products, a huge amount of by-products are generated every year. Major nutritional, financial, and environmental advantages can be achieved by transforming them into functional ingredients for food formulation and fortification. In this review, we investigated various conventional and emerging treatments recently employed to obtain functional ingredients rich in proteins, fibers, and bioactive compounds from vegetables, fish, meat, and dairy by-products. The optimal enrichment level in food as well as the nutritional, techno-functional, and sensory properties of the final food were also discussed. Novel technologies such as ultrasounds, microwaves, and high pressure have been successfully adopted to enhance the extraction of target compounds. The functional ingredients, added both in liquid or powder form, were able to improve the nutritional quality and antioxidant potential of food, although high levels of fortification may cause undesired changes in texture and flavor. This review provides important considerations for further industrial scale-up.

Brown Seaweed Byproduct Extracts Improve Intestinal Motility and Auto-Inflammation in Mice with Loperamide-Induced Constipation.

Sargassum fusiforme and Sargassum fulvellum are types of brown algae used for their nutritional value and medicinal properties, including anti-inflammatory, antioxidant, and anticancer effects. Despite their importance in various industries, many seaweed byproducts containing dietary fiber and polysaccharides are discarded in landfills. These byproducts can be recycled and repurposed for different applications. In this study, we investigated the impact of S. fusiforme food processing byproducts (MbP-SFF) and S. fulvellum food processing byproducts (MbP-SFV) on improving intestinal motility and reducing inflammation in mice with constipation induced by loperamide. To evaluate this, mice were orally administered 500 mg/kg/day of the byproducts once daily for 8 days. Constipation was induced by 5 mg/kg/day of loperamide for two days after oral administration for 6 days. Each sample contained approximately 70% carbohydrates. MbP-SFF had 52.0% mannuronic acid and 18.8% guluronic acid, while MbP-SFV had 36.9% mannuronic acid and 32.9% guluronic acid. These byproducts enhanced fecal excretion and intestinal motility by modulating inflammatory responses. Furthermore, they restored the balance of the gut microbiota disrupted by loperamide, increasing beneficial Bifidobacterium and reducing harmful Staphylococcus aureus. Overall, MbP-SFF and MbP-SFV improved intestinal motility and inflammation by influencing the gut microbiota and inflammatory responses in a loperamide-induced mouse model. These byproducts show potential as ingredients in functional foods aimed at enhancing gut health, potentially reducing waste disposal costs and addressing environmental concerns associated with their utilization.

Poly(3-hydroxybutyrate) production using supplemented corn-processing byproducts through Cupriavidus necator via solid-state fermentation: Cultivation on flask and bioreactor scale

The widespread adoption of Poly(3-hydroxybutyrate) (PHB) encounters challenges due to its higher production costs compared to conventional plastics. To overcome this obstacle, this study investigates the use of low-cost raw materials and optimized production methods. Specifically, food processing byproducts such as corn germ and corn bran were utilized as solid substrates through solid-state fermentation, enriched with molasses and cheese whey. Employing the One Factor at a Time technique, we examined the effects of substrate composition, temperature, initial substrate moisture, molasses, and cheese whey on PHB production at the flask scale. Subsequently, experiments were conducted at the bioreactor scale to evaluate the influence of aeration. In flask-scale experiments, the highest PHB yield, reaching 4.1 (g/kg Initial Dry Weight Substrate) (IDWS) after 72 hours, was achieved using a substrate comprising a 1:1 mass ratio of corn germ to corn bran supplemented with 20 % (v/w) cheese whey. Furthermore, PHB production in a 0.5-L packed-bed bioreactor yielded a maximum of 8.4 (g/kg IDWS), indicating a more than 100 % increase in yield after 72 hours, with optimal results achieved at an aeration rate of 0.5 l/(kg IDWS. h).

Tapioca Crispy Crackers with Ripe Banana Peel: Snack Enrichment with Dietary Fiber and Phenolic Compounds from an Agri-Food Waste

Banana peel is rich in bioactive compounds and dietary fiber. Both tapioca starch and bananas are naturally gluten-free. As a means of waste valorization and snack enrichment, tapioca crispy crackers were enriched with banana peel, with or without flesh. The peel was from cv.Namwa bananas are in the final stages of ripening. Phenolic compounds in the ripe banana peel led to the bitterness of the enriched crackers. To increase the amount of banana peel that could be used, the peel was boiled before being incorporated into a formulation of banana peel, at 30 g /100 g of tapioca starch, and flesh at 8 g/100 g of tapioca starch, by weight. The crackers contained no preservative or synthetic coloring or flavoring agent and were assessed without further seasoning. The product was very well-received with 100% acceptance and 93.33% of the respondents were interested in buying it. More than half of the respondents regarded it as being innovative and tasty. Proximate analyses revealed that the optimized formulation contained 2.28% ± 0.08 of total dietary fiber (about 2,280% compared to 0.01% ± 0.02 of the formulation without banana) whereas no significant increase in protein content was observed. The product contained phenolic compounds at 27.26 ± 0.19 μg TAE/g. Sensory evaluation predicted that the enriched crackers, stored at 35±1 °C in a closed container, were not likely to be rejected due to any unpleasant smell of rancidity for at least 10 days. The phenolic compounds contributed by the boiled banana peel significantly suppressed the rancidification process. The optimized formulation can be used for the development of healthy antioxidant-rich, high-fiber, and high-protein snacks using high-protein food processing by-products.

Valorization of various nut residues grown in Turkiye: Antioxidant, anticholinesterase, antidiabetic, and cytotoxic activities.

The utilization of plant-based residues has been extensively employed for the control of diverse illnesses, owing to their safety and minimal adverse effects. In the current study, it was aimed for the characterization of the bioactive, enzyme inhibitory, and cytotoxic activities of fresh pistachio shell skin (FPSS), green walnut husk and walnut membrane (GWH), almond outer shell and inner brown skin (ASIS), as well as peanut husk and inner skin (PHIS) to be used as industrial food processing by-products. The results showed that the samples exhibited different extraction yields, with GWH having the highest percentage at 15.18%, followed by FPSS at 12.81%, ASIS at 10.29%, and PHIS at 7.80%. FPSS had the highest total phenolic content (16.28 mg gallic acid equivalents (GAE)/g) as well as the best antioxidant capabilities for DPPH (8.96 mg Trolox equivalent (TE)/g), FRAP (11.46 mg TE/g), and ABTS (22.38 mg TE/g) assays. FPSS was followed by PHIS, ASIS, and GWH, respectively. Moreover, the extracts exhibited relatively low activity against acetylcholinesterase, α-glucosidase, and α-amylase compared to standard acarbose or galantamine. Furthermore, the extracts may have the potential to induce cytotoxic effects, varying from moderate to mild, on both cancerous (IC50 = 454.55-617.28 μg/mL) and healthy cells (IC50 = 438.60-490.20 μg/mL). The results of this research showed that shell residues of nut hold promise for a variety of industrial applications spanning the food, pharmaceutical, and cosmetic sectors.

Characterization of holocellulose extracted from agricultural and food processing byproducts via ecofriendly delignification pulping process

AbstractThis study investigated an ecofriendly peracetic acid delignification process to extract holocellulose from various fiber rich plant‐based byproducts (coconut palm spathe/leaf, apple pulp, wine grape pomace, hazelnut shell, and hemp fiber/hurd), and evaluated their physicochemical, morphological, and thermophysical properties in comparison with commercial cellulose nanofibers produced from wood. Holocellulose from coconut palm spathe has long fiber (~846.7 μm), whereas that from wine grape pomace and hazelnut shell exhibits a cylinder shape of particles with short fiber length (~123.8 and ~ 71.1 μm, respectively). Biofilms cast from apple pulp and hemp fiber holocellulose have higher degradation temperature (361 and 358°C, respectively) than biofilms from other materials, thus more thermally stable. All biofilms demonstrate high UV absorbance, and the biofilm cast from apple pulp holocellulose is transparent with smooth surface. Fourier‐transform infrared spectroscopy analysis confirms the presence of cellulose and hemicellulose as the main components in the biofilms, along with traces of residual lignin that remained after the extraction process. This study demonstrates that holocellulose with varied cellulose morphology and polymeric characteristics could be extracted depending on the type of byproducts and be employed to produce sustainable packaging materials.

Special Issue “Pretreatment and Bioconversion of Crop Residues II”—Introduction to the Collection

Bioconversion in biorefineries is a way to valorize residues from agriculture and food processing. Pretreatment is an important step in the bioconversion of lignocellulosic materials, including crop residues. This Special Issue includes nine articles on several pretreatment and bioconversion approaches applied to different agricultural residues and food-processing by-products. The materials addressed in this collection cover straw from wheat, rye, and miscanthus, olive tree pruning residue, almond shells and husks, avocado waste, sweet sorghum bagasse, soybean meal, and residues of non-edible oilseeds.

Utilization and application of bioactive compounds generated from Fish waste and by product as Functional Food Ingredient: A review

The quest for novel functional food ingredients from natural sources is one of the most important discuss in food science and technology. Food industries dispose their valuable waste and some food industries re-process their wastes and used them as functional food ingredients, thereby developed their economy to survive in the neck cutting competition of the market. Enormous volumes of food processing by-products (FPBs) are produced from food manufacturing industries, accounting it as the second-largest quota of food waste generation. Fish known as ‘rich food for poor people,’ supplies good quality of fats, minerals vitamins and proteins to billions of populaces across the globe. However, the fish processing industry on daily basis generates huge wastes leading to the quest for management of these wastes. These wastes which can be referred to as by-products are generated during removal of head; gutting of the fish and during other secondary processing carried out either onboard in fishing vessels or at processing plants on the shores. Over the years there are bids for utilization of fish wastes and by products for production of functional food ingredients using bioactive compounds produced from them. This was aimed at reduction of processing waste, creation of sustainable economic boost, environmental safety while formulating value added functional food which could be of importance to human and animal health or wellbeing. By-products from fish processing such as blood, fleshy chunks of fatty fish, tails, liver from white lean fish, Fish heads, offal, viscera (gut, intestines, etc.), skin and shells have potentials utilization as raw materials for production of value-added functional food ingredients. Bioactive peptides isolated from various fish protein hydrolysates have reported to have several bioactivities such as immunomodulatory, antioxidative antihypertensive, antithrombotic, anticoagulant activities among others Hence from the review, the recovery of bioactive compound and utilization of these by-products are untapped sources for functional ingredients which can be applied in several aspects of food processing for the benefit of manufactures, supply series of nourishments, and consequently advancing the usefulness of the fish waste in consumers’ health and economic benefits of all stakeholders.

Nutritional Composition and Safety Parameters of Mealworms (Tenebrio molitor) Reared on Substrates Derived from By-Products

Mealworms provide a viable option for transforming agricultural and food processing by-products that can be converted into a valuable source of high-quality protein and fat suitable for both animals and humans. Hence, our investigation was aimed at employing sprouted and green potatoes, wheat bran, and by-products from brewers’ production as a comprehensive substrate for rearing mealworms. The nutritional value (fat and protein content) and composition of amino acids (AAs) and fatty acids (FAs) were tested in lyophilized and milled larvae. The results showed that the highest amount of protein was detected in sample 3L (59.18 ± 007%), grown on brewers’ spent grain, whereas sample 2S (with wheat bran) comes out with the highest fat content (34.22 ± 0.491%). It was found that the amount of FAs in the larvae depended on the substrate used: the statistically highest amount of monounsaturated FAs was detected in the sample with sprouted potatoes (1L), the highest content of omega-3 FAs was found in the control sample (4CL), with agar–agar gels, and the sample with brewers spent grains (3L) showed a statistically higher amount of oleic acid. Meanwhile, the highest content of total polyunsaturated FAs (36.23%) was detected in the sample with wheat bran (2L). During the study, 16 distinct AAs have been analyzed, and sample 3L has demonstrated the highest content in 11 instances. It is noteworthy that the sample containing brewers’ spent grain exhibited the highest peroxide levels, indicating oxidation. Meanwhile, the determined number of volatile fatty acids did not exceed the regulatory limits for meat. In summary, it can be asserted that adjusting the substrate is essential for extracting specific amino acids and FAs. However, this could potentially affect the content of peroxides. This adaptation enables the desired chemical composition in larvae, making it suitable for specific purposes such as animal or human nutrition and health enhancement.

Characterization of Langra Mango Peel Powder and Assessment of Its Prebiotic and Antioxidant Potential

The possibility of developing waste by-products of food processing into functional food additives along with probiotics is an interesting avenue to research. This study investigated the nutritional and functional attributes of dried mango peel powder (MPP) of Langra cultivar and its putative potential to act as a prebiotic in the presence of two probiotic strains Lacticaseibacillus rhamnosus NCDC347 and Limosilactobacillus fermentum NCDC143 @ 2.5 & 5% after 24 to 48 h fermentation. Proximate analysis revealed that the MPP contains 6.45 % moisture, 6.34 % protein, 3.88 % fat, 2.50 % ash, 32.86 % crude dietary fiber, and 47.97 % of total carbohydrate content. MP displayed substantial antioxidant potential with 54.6% DPPH inhibitory activity, 15.67 mg GAE/g TPC, 8.88 mg QuE/g TFC, OHC of 1.47 g oil/g, and a WHC of 4.7 g water/g. MPP could selectively stimulate the growth of two probiotic strains over enteric bacteria. It was revealed that a combination of MPP @5% with L. fermentum NCDC143 after 24 h fermentation had the best in vitro prebiotic activity score of 3.35 and 3.53 against Escherichia coli ATCC 25922 and Enterococcus faecalis NCDC114, respectively. The prebiotic activity score of MPP was better than commercial prebiotic malto-dextrin for all combinations of probiotic and enteric strains tested. The percentage DPPH inhibition activity of MPP increased during fermentation with L. fermentum NCDC143, highlighting its role as a source of antioxidants. These findings contribute to the formulation of synbiotic products that are able to maintain selected healthy microbiota in the human gut.

Investigation of phenolic compounds recovery from brewery wastewater with coupled membrane and adsorption process

Recovery of phenolic compounds from food-processing by-products represents an interest for various industrial sectors. The potential of a coupled ultrafiltration and adsorption or ion exchange resin process was analyzed to recover phenolic compounds from a brewery liquid residue. Ultrafiltration yielded a 95% removal of turbidity-causing compounds without significant modification of the chemical composition of brewery by-products. After a pH optimization step, ten different macroporous resins, including MN202, SP700, HP2MGL, LXA8302, LWT510, XAD16N, FPX66, WA20, WA30 and SCAV4, were screened for phenolic compounds sorption. Resins were selected through a multi-step batch test procedure according to their performance in phenolic compounds adsorption capacity, phenolic compounds selectivity compared to carbohydrates and price. The strong base resin SCAV4 with OH- counter ion showed the highest adsorption capacity, 35.4 ± 0.8 mg·gdryresin−1, with selective sorption of phenolic compounds. Higher temperatures of 48 °C improved the adsorption and desorption performances of LXA8302 and SCAV4 resins, compared to 25 °C. Up to 70% of phenolic compounds were desorbed from adsorption resin with adequate solvent.