Search Results (33)

Apple fruit is among the most consumed fruits in the world, both in fresh and processed forms (e.g., ready-to-eat fresh slices, juice, jam, cider, and dried slices). During apple consumption/processing, a significant amount of apple residue is discarded. These residues can also be interesting materials to exploit, particularly for direct valorization in the design of added-value foods. In fact, apple waste/by-products are rich in essential components, including sugars, proteins, dietary fibers, and phenolic compounds, as they comprise apple peels, seeds, and pulp (solid residue of juice production). In this sense, the current review paper presents an overview of the nutritional composition of apple waste/by-products, and mainly apple pomace, highlighting their application in producing value-added products through microbial biotechnology. If appropriately managed, apple by-products can generate a variety of useful compounds required in food (as well as in feed, pharmaceutics, and bioenergy). Recent strategies for the synergic use of apple waste/by-products and microbial resources such as lactic acid bacteria and yeasts are discussed. This review contributes to defining a reference framework for valorizing apple waste/by-products from a circular economy perspective through the application of bioprocesses (e.g., fermentation), mainly oriented towards designing foods with improved quality attributes. Full article

This work aimed to evaluate the effects of dried apple pomace (DAP) on the fermentation characteristics and proteolysis of alfalfa silages. The alfalfa was ensiled with (1) no additives (control), (2) 5% DAP, (3) 10% DAP and (4) 15% DAP based on fresh weight (FW) for 1, 3, 7, 14, 30 and 60 days, respectively. With the increasing proportion of DAP, lactic acid bacteria (LAB) count, lactic acid (LA) and dry matter (DM) content linearly (p < 0.05) increased, while the pH, the content of acetic acid (AA), propionic acid (PA), butyric acid (BA) and ammonia nitrogen (NH₃-N) linearly (p < 0.05) decreased during ensiling. The 10% and 15% DAP silages had significantly (p < 0.05) lower aerobic bacteria (AB), yeast and enterobacteria counts than the control during ensiling. The contents of nonprotein nitrogen (NPN), peptide nitrogen (peptide-N) and free amino acid nitrogen (FAA-N) and activities of carboxypeptidase, aminopeptidase and acid proteinase linearly (p < 0.05) decreased as DAP proportion increased during ensiling. On day 60, the addition of DAP significantly (p < 0.05) decreased the contents of tryptamine, phenylethylamine, putrescine, cadaverine, histamine, tyramine, spermidine, spermine and total biogenic amines compared with the control. As the DAP ratio increased, the contents of threonine, valine, isoleucine, leucine, phenylalanine, lysine, histidine, arginine, aspartic acid, serine, glutamic, total amino acids, crude protein (CP) and water-soluble carbohydrates (WSCs) linearly (p < 0.05) increased, while the contents of glycine, alanine, cysteine, and proline linearly (p < 0.05) decreased on day 60. Overall, the addition of 15% DAP was optimal as indicated by better fermentation quality and less proteolysis than other treatments. Full article

This study investigated the impact of adding raspberry pomace to the phenolic content and biological properties of freeze-dried apple/raspberry bars. The bars were prepared by replacing apple puree with raspberry pomace (5–50%), and their phenolic compounds were assessed using ethanol and buffer extracts. This work also explored the potential bioaccessibility of phenolic compounds in enriched bars through a simulated digestion process (digest). Antioxidant, anti-inflammatory (LOX, COX-2 inhibition), antihypertensive (ACE inhibition), and antiproliferative effects on AGS and HT-29 cancer cells were evaluated. The total polyphenol content was highest in the all bar variants post-digestion. The highest—904.26 ± 23.5 mg/100 g—was determined for the B50 sample In the enriched bars, the concentration of chlorogenic acid decreased from 6.99 ± 1.08 mg/L for BP5 to 2.75 ± 0.32 mg/L for BP50, but the ellagic acid concentration increased from 1.46 ± 0.02 mg/L for BP5 to 12.73 ± 0.09 mg/L for BP50. Among the tested extracts, the highest antioxidant and LOX, COX-2 inhibiting activity was determined for digest. The ability to neutralize free radicals increased with raspberry pomace addition from 3.63 ± 0.26 mM TE/100 g for BC to 5.58 ± 0.22 mM TE/100 g for the BP50 sample. ACE inhibition was quite similar for ethanolic and digest extracts, but much weaker for buffer extracts. The lowest EC50 value was 1.04 ± 0.03 mg/mL for the BP30 ethanolic sample. Analyzed extracts showed antiproliferative activity against both tested cell lines. The EC50 values for HT-29 cancer cells decreased from 0.354 ± 0.031 mg/mL for BC to 0.026 ± 0.006 mg/mL for the BP50 digest sample. It can be assumed that the BP30 bar best met the assumed criteria, and is optimal for both sensory quality (receiving an average score of 4.45) and health benefits. Full article

Apple and ginger mixed pomace is a by-product that can be valorized by drying. In this study, mixed pomace was subjected to hot-air drying (HAD) at 45, 62, and 70 °C and stepwise at 45 °C followed by at 62 °C or the reverse, at 62 °C followed by at 45 °C (2.5 mm layer), and microwave drying (MWD) at 100, 180, and 300 W (2.5 mm and 1.5 mm layers) and stepwise at 100 W followed by at 300 W (2.5 mm layer). The results show that the Crank model well fitted the HAD kinetics, with a water effective diffusivity (Deff) of 2.28 ± 0.06 × 10⁻¹⁰–4.83 ± 0.16 × 10⁻¹⁰ m²/s and energy of activation of 23.9 kJ/mol. The step approach of drying at 45 °C followed by at 62 °C resulted in a higher Deff than the reverse approach (drying at 62 °C followed by at 45 °C). The Midilli et al. model presented a good fit for the MWD kinetics. The drying time was calculated using these models to achieve 12% moisture content in the pomace and found to be 125.0 ± 9.2–439.5 ± 118.2 min for HAD, and 11.1 ± 0.2–61.5 ± 6.0 min for MWD. The specific energy required was 410.78 ± 6.30–763.79 ± 205.4 kWh/kg and 1.32 ± 0.01–2.26 ± 0.05 kWh/kg, respectively. MWD at 180 W preserved the total phenolic content and the antioxidant activity (ABTS, DPPH) better than HAD at 62 °C. The former technology also preserved the pomace color well, with a low color difference, ΔE, of 7.39 ± 1.1. Therefore, MWD is more promising than HAD to dry apple and ginger pomace, reducing the environmental impact of the drying process due to its lower energy consumption, shorter drying time, and better quality. The dried product could be converted into apple and ginger pomace flour to be used as a novel food ingredient. Full article

Replacing the amount of sugar in pastries with functional ingredients may be a strategy of interest to food manufacturers. Reducing the content of sugar in pastries and bakery products could be a measure to reduce diseases such as obesity, diabetes, cardiovascular disease, tooth decay, and cognitive impairment. Additionally, energy consumption, greenhouse gas emissions, and global warming potential are the main issues in sugar beet agricultural production systems. Due to the multiple roles that sugar has in the dough (i.e., provide energy, sweeten, improve the structural characteristics, extend shelf life, limit the swelling of the starch, give color and flavor to ripe products, and ensure the preservation of products), there have been attempts at substituting sugar in percentages of up to 100% in different products such as cakes, muffins, pies, biscuits, cookies, and bread. From the points of view of technology and consumer perception, the best substitutes are apple puree, inulin, oligofructose, stevia, apple pomace, polydextrose, dried apples, Nypa fruticans sap, grape juice/syrup, and date powder/syrup. Depending on the substituent, when substituting sugar in percentages from 10 to 100%, improvements were obtained in terms of texture, rheological properties, sensory properties, consumer acceptability, and physicochemical and nutritional properties. Full article

The present study was conducted to develop turkey sausages by incorporating freeze-dried apple pomace (FDAP) at 3, 5, and 8% by replacing turkey breast meat. Three sausage formulations and the control of turkey sausages were subjected to physicochemical properties: proximate content, water-holding capacity (WHC), cooking yield, pH, color, textural parameters, antioxidant activity, and microbiological and sensory properties. The parameters were analyzed during storage from days 0 to 7. The addition of FDAP to turkey sausages resulted in a significant (p ≤ 0.05) decrease in moisture and protein contents, whereas no significant difference was found in fat and ash contents. The increased incorporation of FDAP resulted in decreased pH, cooking loss, lightness, redness, and yellowness in turkey sausages, whereas an increase in total phenolic content, fiber content, ABTS, and DPPH values was observed. FDAP, as a low-cost source of valuable phenolic content, strongly inhibited microorganism growth during the storage of turkey sausages. The sensory scores of turkey sausages containing 3% FDAP for other sensory traits, such as flavor, texture, juiciness, tenderness, and overall acceptability, were comparable to those of the control. Scores for sensory attributes declined significantly with a further increase in FDAP in turkey sausages. It is concluded that turkey sausages with very good acceptability can be prepared by incorporating freeze-dried apple pomace each at a 3% level. Full article

Pomace is a by-product resulting from the pressing of fruits and vegetables into juices, and it is typically treated as waste. Interestingly, pomace contains minimal amounts of protein and fat but is characterized by its high polyphenol and dietary fiber contents, which may have health benefits for human physiology. Therefore, they are a potentially attractive raw material for the food industry, but to our knowledge, no smoothies with their addition have been prepared and described so far. Consequently, products derived from apple juice, incorporating different doses of fresh (6% and 12%) and dried (3% and 6%) black or red currant pomace, were formulated, and their physical properties, chemical composition, bioactive compound content, and health-promoting potential (in vitro antioxidant and antidiabetic activity) were evaluated. Additionally, the products underwent sensory assessment by consumers. The fortified beverages exhibited different physical characteristics and chemical compositions than apple juice. All smoothies were characterized by higher concentrations of anthocyanins, flavonols, and procyanidin polymers compared to the base product. Moreover, 75% of them exhibited a significantly elevated phenolic acid content as well as a higher concentration of flavan-3-ols. The majority of fresh smoothies exhibited significantly higher in vitro antioxidant capacities and increased in vitro α-amylase and α-glucosidase inhibitory effects compared to the base product. The highest ABTS activity was recorded in the variant with 6% dried black currant pomace. In turn, the smoothie with 3% dried red currant pomace had the most effective FRAP effect and, together with the product containing 12% fresh black currant pomace, ORAC antioxidant activity and α-glucosidase inhibition also. The introduction of 6% dried red currant pomace led to the creation of a beverage that most effectively inhibited α-glucosidase. The study showed that the application of various types of pomace, mainly that of black currant, into apple juice enables the development of new functional products with sensory attributes that are favorably evaluated by consumers. Full article

The valorization of fruit and vegetable side-streams from the juice industry is an important contribution to the optimization of food resources and is an environmentally friendly practice in line with the concepts of circular economy and sustainability. The aim of this work is to incorporate them back into the food value chain by adding them as ingredients in staple foods like crackers. This is also important in terms of food fortification, as they are rich in nutrients and bioactive compounds. Crackers are popular snacks with a huge global market value, enjoyed by consumers of all ages. The current study aims to integrate flour from dried apple and carrot pomaces, resulting from juice processing, as natural ingredients with potential health benefits. The incorporation levels ranged from 20 to 40% dry weight in crackers, and their impact on physicochemical and mechanical properties was evaluated, as well as bioactivity (potential impact on health) and sensory acceptance. The addition of pomaces resulted in significant changes in texture and color, as well as enhancing the antioxidant activity of the crackers. Crackers containing pomace flours, except for the cracker with 40% carrot pomace, showed a high overall sensory acceptability and good intentions to buy. Full article

Malolactic fermentation (MLF) is a biological process of deacidification of wines that may also help to increase the microbiological stability of the product and to enhance its sensorial attributes, in particular its aromatic profile. MLF can occur spontaneously due to the presence of indigenous bacteria in the environment of fermented beverages such as wines and ciders. However, the inoculation of lactic acid bacteria (LAB) starter cultures could prevent potential losses and standardize the process. The industrial-scale production of these starter cultures requires cost-effective, sustainable, and feasible approaches. A possible approach to acquire bacterial biomass, while addressing waste disposal concerns, is the use of by-products from the apple juice industry, such as apple pomace. Moreover, to ensure the long-term viability and activity of starter cultures, appropriate preservation methodologies need to be developed. Thus, the aim of the present study was to evaluate the growth of two Lactiplantibacillus plantarum strains, UNQLp11 and UNQLp155, in supplemented apple pomace and to optimize the preservation conditions. Cultures were either frozen or freeze dried (trehalose (20% m/v) as a protective agent, potassium phosphate buffer (pH 7), and a combination of trehalose and buffer), and then cell viability and malolactic activity were analyzed under wine stress conditions. Notably, the combination of phosphate buffer at pH 7.0 and trehalose emerged as the most effective preservation strategy for freeze drying, exhibiting enhanced viability and malic acid consumption for the two strains evaluated. These findings underscore the inexpensive and sustainable viability of using a semi-solid medium formulated with apple pomace for LAB biomass production and subsequent preservation. Full article

The study aimed to evaluate the effect of storage temperature on quality changes in freeze-dried carrot–orange–ginger (COG) snacks obtained with 2% of apple (AP) or blackcurrant (BP) pomace powder or 1.5% of pectin (LMP). The material was stored at 4, 25 and 40 °C for 1, 3, 6 and 12 months in pouches impermeable to vapour, oxygen and light. Water content and activity, texture, colour, total polyphenol content and antioxidant activity were examined to evaluate the products’ quality. During storage, water content and activity fluctuations were noted, but no critical values were exceeded. Texture properties remained stable in snacks with pomace powders compared to those with pectin, the hardness of which significantly decreased when stored at ambient and elevated temperatures. However, the product with pectin was found to change colour the least over time. The results obtained for chemical properties were not clear, but they strongly indicated the occurrence of the transformation of some chemical compounds. Overall, a lowered temperature helped to maintain the quality of the freeze-dried snacks for the longest time. The presented research contributes to the general knowledge of the behaviour of innovative products with the addition of nonconventional but sustainable compounds, revealing the potential for quality and stability improvements. Full article

Numerical investigations on the flowability of pulverized biomass are crucial for agriculture, aiding in optimizing biomass use, crop residue management, soil health improvement, and environmental impact mitigation. Rising interest in biomass and conversion processes necessitates deeper property understanding and technological process optimization. Moisture content is a key parameter influencing biomass quality. In this paper, computer simulations of shear tests depending on the moisture content using the discrete element method were carried out and compared with experimental results. An experimental study and modeling for Jenike’s direct shearing apparatus was carried out. A swelling bed model was proposed to account for the effect of moisture. The swelling bed model assumed an increase in biomass grain vorticity proportional to the moisture content. The model was solved using the discrete element method (DEM). The model considers the effect of moisture on the values of Young’s and Kirchoff’s moduli for biomass grains. The model assumed that moisture is not present in surface form, the total amount of moisture is absorbed into the interior of the material grains, and the volume of a single grain increases linearly with an increase in the volume of the absorbed moisture. The tested materials were pulverized sunflower husks, apple pomace, distiller’s dried grains with solubles (DDGS), meat and bone meal (MBM), and sawdust. Samples with moisture contents of 0%, 10%, 20%, and 30% were tested. The best agreement of the model with the experimental data was observed for the most absorbent materials in which moisture was not present in surface form, such as apple pomace, DDGS, and sawdust. Research data are important for the proper design of biomass storage, transportation equipment, and utilization as feedstock for bioenergy production or soil enrichment. Full article

(1) Background: The effective management of waste and by-products generated in the food industry helps development and implementation of ranges of health-promoting products. The manufacturing of apple juice and cider results in the generation of large quantities of apple pomace. (2) Methods: This paper outlines the concept of a technological process for industrial-scale production of edible oil with a health-promoting fatty acids profile using dried apple pomace as a raw material. (3) Results: Described approach allows for innovative and profitable industrial-scale utilization of the pomace generated from apple juice production. This paper presents a new technological line for apple seed separation intended for oil pressing. (4) Conclusions: The new technological approach could increase the production of apple seed oil. Because of the growing needs in managing post-production waste and by-products, apple seed oil produced from apple pomace on an industrial scale may become a new, attractive product in the functional food market. The fatty acids profile of apple seed oil is high in polyunsaturated fatty acids and can beneficially influence health. The technology outlined here is in the conceptual phase and requires further research. Full article

Industrial fruit by-products are now being utilized as animal feeds for several reasons. They may substitute the conventional cereal feeds, and also offer economic and environmental benefits. One of the most important industrial fruit by-products is apple pomace, which can be used as a source of energy in the ration of ruminant species, including dairy cattle. The aim of the present study was to evaluate the effect of feeding dried apple pomace to dairy cattle on ruminal fermentation, fatty acid concentration, microbial populations, and methane production. The experiment lasted 64 days and was conducted with 4 cannulated commercial dairy cows. The control animals received a standard diet, while the experimental animals was fed a standard diet supplemented with 150 g/kg DM dried apple pomace. Ruminal fluid samples were collected at three different time intervals. The samples were obtained at 0-, 3-, and 6-h post-feeding. The ruminal fluid was used to assess the ammonia concentration, pH, volatile fatty acids (VFA), long-chain fatty acids (FA), microbial population. A number of ruminal fermentation variables changed as a result of the addition of dried apple pomace to the standard diet. Ruminal pH slightly increased (p < 0.01) while the ammonia concentration decreased (p < 0.01) by 46%. There was a significant decrease in total protozoa count (p < 0.01) and an increase (p < 0.01) in total volatile fatty acids. In addition, there was a decline in methane emission (p = 0.05) by 8% due to dried apple pomace feeding. To sum up, this study demonstrated a positive effect of 150 g/kg DM dietary dried apple pomace on ruminal metabolism including a decrease in ammonia concentration and methane emissions, alongside with an increase in total ruminal VFAs, higher nutrient digestibility, and milk production. Also, beneficial changes to the ruminal fatty acid profile resulting from reduced biohydrogenation were observed although a decreased content of the C18:2 cis 9 trans 11 isomer was also noticed. The dietary inclusion of DAP can serve as a valuable, sustainable, and environmentally friendly dietary component for dairy cows. Full article

Cereal bars are so-called convenience foods. Consumers value these products as a healthier alternative to traditional chocolate bars. Since these snacks usually contain added dried fruit, they have high potential for the utilisation of waste materials from the fruit industry. The study aimed to determine the effect of fortification of cereal bars with grape and apple pomace on their nutritional value, physical properties, and sensory quality. The control recipe was modified by replacing 10 or 20 g of sultanas with apple or grape pomace. The fortification with these food by-products resulted in a significant increase in the moisture content of the products, an increase in soluble fibre content, and a decrease in the level of antioxidant compounds. The strength of the cereal bars supplemented with grape and apple pomace increased. In addition, the panellists noticed a colour difference compared to the unmodified product (2 < ΔE < 5). A positive effect of the addition of the fruit pomace on the visual characteristics of the cereal bars was also observed. No changes were observed in the tastiness of the product. On the other hand, the aroma of the modified products and the texture of the bars containing the apple residue were less acceptable. In conclusion, cereal bars containing grape pomace and up to 10 g of apple pomace are characterised by high soluble dietary fibre content and desirable sensory and mechanical properties and are therefore recommended for industrial production. Full article

The article investigates the process of pectin extraction using ultrasonic and microwave techniques from apple pomace generated during juice production in the context of circular bioeconomy. The extraction yield, equivalent mass, content of methoxyl groups, content of anhydrogalacturonic acid, and degree of esterification of pectin were investigated. These indicators varied depending on the parameters and extraction method. The resulting pectin displayed a co-extracted total polyphenol content (TPC) ranging from 2.16 to 13.05 mg GAE/g DW and a DPPH radical inhibition capacity of 4.32–18.86 μmol TE/g. It was found that the antioxidant activity of raw pectin is correlated with TPC and with the content of terminal groups released during the polysaccharide degradation process. The extracted pectin was used as a binding and coating agent for dried fruit bars. Evaluation of water activity (a_w), TPC and total flavonoid content (TFC), together with sensory and microbiological analyses of the fruit bars over a period of 360 days, revealed a protective effect of pectin: reducing moisture loss, minimizing the degradation of bioactive compounds during storage, and maintaining the potential antioxidant activity of the product. Full article