Apple Processing Industry Research Articles

Insights into the environmental benefits of using apple pomace for biosorption of lead from contaminated water

The apple processing industry generates large quantities of organic waste, presenting a major source of organic contamination. Consequently, finding an effective solution for valorizing this waste has become a pressing issue. This study aims to address two key concerns: (i) solving an agricultural problem by efficiently using agri-food residue, and (ii) removing lead, an extremely toxic element, from contaminated waters to mitigate environmental pollution. Two biosorbents were tested: raw apple waste (RA), obtained from a mixture of apple varieties, and the same material after extracting valuable bioactive and reusable components, extracted apple (EA). The study evaluated the influence of pH, initial biosorbent mass, adsorption kinetics, and equilibrium isotherms. The results are very promising, showing a lead removal efficiency of 82 % for RA and 100 % for EA at a low initial concentration of the solution of 20 mg Pb2⁺/L and an optimal pH of 5 ± 0.5. The Langmuir model predicted a maximum adsorption capacity of 44.6 mg/g for RA and 48.6 mg/g for EA. These findings demonstrate that apple waste, even after selective extraction of valuable bioactive components, can be effectively used for environmental remediation on a practical scale.

Irradiation-induced modifications of apple seed protein isolate: Exploring techno-functional, structural, thermal, and morphological characteristics

Waste valorization of apple seeds for protein extraction is a sustainable approach to the management of apple seed waste in the apple processing industry. The purpose of the research is to study the modification of apple seed protein isolates under different doses of irradiation on functional, structural, thermal, and morphological characteristics. Different irradiation doses of 8, 15, 20 25, and 50 kGy showed significant variations in protein content (88.70%–86.45%), total phenolic content (774.13–285.42 mg GAE/100g), and color profile of the apple seed protein. Irradiation altered the apple seed protein isolates' functional properties with increased foaming properties and emulsifying properties and decreased water and oil absorption properties. Irradiation induces denaturation and cross-linking in the apple seed protein structures, which increase surface hydrophobicity (708.66–1740.66), decreased zeta potential (−18.60 to −39.39 mV), and alteration in protein secondary structures with decreased α-helix (11.52–10.43 %), β-sheet content (60.82–60.13%), and random coils (16.82–16.19%), and increased β turns (10.79–13.22 %). DSC and TGA analysis revealed improved thermal properties using irradiation doses of 8–20 kGy whereas reduction for 25–50 kGy in irradiated apple seed proteins. Scanning electronic microscopy showed pores and aggregated structures of irradiated apple seed protein isolates. The study revealed the potential of irradiation as one of the non-thermal techniques for modifying apple seed protein isolates for protein valorization in various food applications.

Advancing Sustainable Nutrition: Enhancing Physical and Nutritional Qualities of Cookies with Apple Pomace Extrudates

Apple pomace is a by-product of the apple processing industry and can be used for various uses such as animal feed, for composting, or to extract valuable compounds such as pectin or antioxidants. In recent years, it has also gained attention as a potential food ingredient due to its fibre content and antioxidant properties. The aim of this study was to examine the effect of three parameters: the percentage of wheat flour replaced by extrudate (5%, 10%, and 15%), the percentage of apple pomace in the extrudate (15%, 30%, and 45% based on the mass of corn grits), and the particle size of the extrudate (<250 µm; 250–1000 µm; 1000–2000 µm) on the properties of cookies, using the Box–Behnken experimental design. The addition of extrudates enriched with apple pomace significantly increased the total fibre and ash content of the cookies. The hydroxymethylfurfural content also increased, but not above the permitted limits (25 mg/kg). The sensory quality was strongly influenced by the particle size, especially the hardness, graininess, and appearance of the cookies. The addition of extrudate led to a darker colour of the cookies and a significant increase in the proportion of red tones, but generally had no negative influence on the acceptability of the cookies and their microbiological stability during the 6-month storage period.

Apple Pomace Extract Improves MK-801-Induced Memory Impairment in Mice.

Alzheimer's disease (AD) is a neurodegenerative disease that involves progressive cognitive decline accompanied by synaptic degeneration and impaired neurotransmission. Recent studies revealed that apple pomace, a waste byproduct of the apple processing industry, has beneficial health properties, but its potential to prevent and treat AD has not been determined. Herein, we examined the effects of apple pomace extract on N-methyl-D-aspartate receptor antagonist MK-801-induced memory impairment in mice. Repeated treatment with apple pomace extract for 7 days reversed the MK-801-induced impairment of associative memory and recognition memory. RNA sequencing revealed that repeated treatment with apple pomace extract altered the gene expression profile in the hippocampus of mice. Real-time PCR showed that apple pomace extract induced upregulation of the mRNA expression for Zfp125 and Gstp1. Furthermore, gene sets related to synapse and neurotransmission were upregulated by apple pomace extract. These findings indicate that apple pomace extract may be useful for the prevention and treatment of AD.

EXPLORATION OF THE BIOACTIVE COMPOUNDS OF MALUS DOMESTICA AND POSSIBILITIES OF USING BY-PRODUCTS OF FRUIT PROCESSING IN THE JUICE INDUSTRY – REVIEW

The by-products of the apple processing industry are abundant in nutrients and bioactive compounds that can improve the nutritional properties of food products and have the potential to prevent or treat a number of diseases, representing an opportunity for the food industry. In the current world context, where the focus is on sustainability and the efficient use of natural resources, apple by-products are becoming more and more relevant. The purpose of this paper was to analyze the specialized literature regarding the chemical composition of by-products from apples as well as their integration potential in the food industry. Current research is focused on the development of new methods of valorizing these by-products, which allow to obtain ingredients with improved functional properties, and as consumers become more and more aware of the benefits of healthy foods, apple by-products should represent an increasingly attractive raw material for the food industry. As the food industry generates effective alternatives for the integration of by-products, they will become an important segment on the consumer market.

Sustainable utilization of apple pomace and its emerging potential for development of functional foods.

Apple pomace, a byproduct of apple processing industry, possesses nutritional components which are of great interests for health aspects. Apple pomace is a good source of dietary fiber, minerals, carbohydrates, phenolic, and antioxidant compounds. These bioactive compounds can be extracted by different extraction techniques which have been comprehensively described in this review article. Furthermore, the incorporation of apple pomace as functional ingredients in different food products like bakery items, extrusion-based snacks, meat, dairy, and confectionary products to improve the commercial value and health benefits has been discussed briefly. This review article can be a helpful tool for industrialists, innovative researchers, and waste management authorities to manage the apple waste in an appropriate and sustainable way.

INVESTIGATION OF THE EFFECT OF APPLE POMACE ON THE TEXTURAL CHARACTERISTICS, FIBRE CONTENT, AND MOISTURE CONTENT OF SPONGE CAKES

Apple pomace, a by-product from apple processing industries, is a popular raw material, which has characteristics of a rich nutritional component, so its utilisation is of great interest. The purpose of this research was to study the effect of apple pomace on the textural characteristics and moisture and fibre contents of sponge cakes. Besides, the relationship between the properties under examination has been investigated. Rheology encompasses many characteristics of the product and plays a pivotal role in consumer acceptance. Rheology, in particular, considers the flow and deformation of bakery products. Sponge cakes were produced with wheat flour partially (by 15%, 25%, and 50%) replaced with apple pomace powder. The addition of 15% and 25% of apple pomace to sponge cakes leads to significant differences in the textural indicators, and with the addition of 50% of apple pomace, there is a maximum improvement in all textural characteristics. With an increase in the amount of apple pomace added, there is an increase in the content of fibre and moisture in the sponge cakes. Apple pomace is used as a valuable source of food fibre in the cake technology. The correlation analysis has found that fibre and moisture changes exhibit a strong correlation with rupture deformation and stickiness. Very strong and statistically significant dependence with a negative value has only been found between the moisture content and stickiness (r = ‑0.965, p<0.05). This statistically significant dependence shows that as the fibre content in sponge cakes increases, the stickiness values decrease due to the negative value of the Pearson coefficient (r = -0.965, p<0.05). From the correlation coefficients, it has been shown that the rupture force and deformation exhibit the same very strong and statistically significant correlation with the textural characteristics – rupture energy, hardness, gumminess, and compressive strength (r = 0.993, r = 0.984, r = 0.996, and r = 0.999, p<0.05). The Pearson correlation coefficients of rupture energy are positive and statistically significant in relation to hardness, gumminess, and compressive strength (r = 0.957, r = 0.983, and r = 0.992, p<0.05). These strong and statistically significant dependences are found between Pearson’s hardness coefficient on the one hand and gumminess and compressive strength on the other (r = 0.992 and r = 0.984, p<0.05).

Superfine grinding improves the physicochemical, sensory and functional characteristics of Hanfu apple pomace

SummaryApple pomace (APP) is the main by‐product in apple processing industry with abundant functional components. To improve the APP economic value, superfine grinding (SG) was used as an effective processing method. The result showed that SG provided great uniformity and particle size of APP. Also, with SG treatment, the water‐holding capacity and oil‐holding capacity increased from 7.50 to 8.13 g g−1 and from 2.07 to 3.81 g g−1, respectively. Furthermore, SG enhanced the sensory properties by increasing the brightness, yellowness and sweetness and decreasing the sourness and bitterness of APP. For functional properties, SG increased total phenols content, total flavonoids content and the soluble dietary fibre from 5.83 to 8.86 mg g−1, from 4.39 to 6.43 mg g−1 and from 8.50% to 14.51%, respectively. Therefore, SG improved the physicochemical, sensory and functional characteristics of APP powder. The results would provide important information for applying SG techniques in processing APP or other fruit by‐products for future commercial market purposes.

Improving oxidative stability of soyabean oil by apple pomace extract during deep frying of french fries

Repetitive use of same oil for deep-frying over extended period results in the production of various harmful compounds thus posing a serious health threat to consumers. Apple pomace, a by-product of apple processing industry is considered a rich source of various bioactive compounds, thus would be of great interest to the frying industry. The aim of this study was to explore the effect of apple pomace extract (APE) on the oxidative stability of soyabean oil during deep frying of french fries and compare it with its highest polyphenolic fraction quercetin (QE) and synthetic antioxidant tertiary butyl hydroquinone (TBHQ). Total phenols (TP) and Total flavonoid content (TFC) of APE obtained from ultrasound assisted extraction (UAE) was found to be (5.58 ± 0.27 mg GAE/g) and (5.42 ± 0.45 mg QE/g) respectively with an antioxidant activity of 76% and (9.9 mM As acid/mg) as determined by DPPH and FRAP assay. Soyabean oil enriched with natural antioxidants show higher thermal stability and quality in terms of various physico-chemical indices and sensory evaluation as compared to control and TBHQ enriched oils. Transfatty acids (TFA) in both control and antioxidant enriched oils during frying were found in higher concentration crossing the legal limit of 2%. The thermal stability of oils conferred by antioxidants follows this order QE ˃APE ˃TBHQ ˃ Control. Thus, natural antioxidants obtained from agro-industrial waste have the great potential to replace synthetic antioxidants effectively in conferring stability to deep-fried oils.

Ultrasound-Assisted Extraction and Characterization of Polyphenols from Apple Pomace, Functional Ingredients for Beef Burger Fortification.

Currently, there is an increasing interest to valorise agri-food waste containing bioactive compounds with potential health benefits. In this paper, the recovery of functional molecules from apple pomace, the most abundant by-product of the apple processing industry, was carried out by ultrasound-assisted extraction (UAE) on fresh and freeze-dried samples. UAE extract, obtained by double extraction of freeze-dried apple pomace, was subjected to chromatographic and spectrophotometric characterization. It showed good levels of total phenol content, high antioxidant activity, and interesting antioxidant compounds (quercetin derivatives, chlorogenic acid, phloridzin). Subsequently, freeze-dried apple pomace, containing 40.19% of dietary fibre, was used as a fortifying agent for beef burgers (4% and 8%). The results concerning colour and sensory analysis of the fortified products were graded even better than the control (0%). The improved fibre and phenol content, together with the neutral flavour, represent the most interesting characteristics of fortified burgers. The results confirm that UAE was a successful technique for extracting phenol compounds and that the addition of apple pomace represents a valid approach to increase the health properties and palatability of beef burgers, including for consumers who do not like meat.

Circular economy in apple processing industry: Biodiesel production from waste apple seeds

Apple pomace is a solid waste derived from the apple processing industry. To foster sustainability, the apple processing industry must implement the circular economy model of biorefinery and treat apple pomace as a valuable source of apple seed oil. For the first time, this study dealt with the design, economic, and potential environmental impact assessment of biodiesel production from apple seed oil obtained from apple pomace. An Aspen Plus? and WAR? software were used to evaluate the designed biodiesel production. The main production steps were the supercritical CO2 extraction, the methanolysis of apple seed oil, the methanol recovery, and the biodiesel separation. The production facility was assumed to process 24 tons of apple seeds daily. The total capital and production costs were 1.26 US$ million and 2.82 US$ million, respectively. If revenues from selling apple seed meal as cattle feed were included, a biodiesel price could be 0.39 US$/kg. The process was environmentally friendly when apple seed meal was not treated as waste.

Barrier and motivations implementation of safety and halal assurance for apple processed products: A review

Consumers are increasingly critical and require transparency of information related to food quality. As such, the warranties of safety and halal processed apple products are increasing. Therefore, the apple processing industry should implement various systems to obtain product safety and halal certificates. This certification is not only based on the final products, but starts from the procurement of raw materials, production processes, to the distribution with evidence of consistency of implementation. Safety and halal implementation have various obstacles and challenges, especially for micro and small businesses. This article reviews the barrier factors and motivations for the implementation of safety and halal assurances for processed apple products, especially in micro and small businesses. The study results show that the main motivations for apple processing businesses include improving product safety and quality, creating satisfaction and fulfilling consumer demands, improving company image. In addition, the micro and small-scale food industries also face various obstacles, namely human resources, finance and infrastructure. These barriers can be overcome by a commitment to management, effective communication, cost management, education and training, operating procedures, supplier management, and external supports. Research regarding strategies to implement halal and safety guarantees for small-scale apple processing businesses is needed.

Application of artificial neural network‐genetic algorithm and response surface methodology for optimization of ultrasound‐assisted extraction of phenolic compounds from cashew apple bagasse

AbstractThis study explores the effect of ultra‐sonication on the extraction of phenolic compounds of cashew apple bagasse (CAB). The extraction was conducted at different combinations of treatment time (5–15 min), ultrasound amplitude (30–60%), and bagasse to solvent ratio (30–50 g/ml) for maximum yield of total phenolic content (TPC), total tannin content (TTC), and β‐carotene content. Both response surface methodology (RSM) and artificial neural network (ANN) were used to model and optimize the process parameters. The optimum conditions achieved using RSM were: treatment time of 12 min, ultrasound amplitude of 55%, and bagasse to solvent ratio of 45 g/ml. In contrast, the optimum conditions proposed by ANN were: treatment time of 15 min, 60% amplitude, and 50 g/ml bagasse to solvent ratio. The TPC, TTC, and β‐carotene content was determined under RSM optimized conditions as 29.04 mg GAE/g, 26.70 μg tannic acid/g, and 18.12 μg/g, respectively and under ANN optimized conditions as 30.61 mg GAE/g, 30.80 μg tannic acid/g, and 19.50 μg/g, respectively. All the statistical parameters showed the lowest value in the ANN model than the RSM model with the highest coefficient of determination (R2). The measured value of the TPC, TTC, and β‐carotene content at optimized conditions were in agreement with the predicted value obtained from the above models. Besides these, the ultra‐sonication significantly increased the TPC, TTC, and β‐carotene content while comparing with conventional solvent extraction. Hence, this method could be an effective green method over conventional technologies to extract phenolic compounds from CAB.Practical ApplicationsThe by‐products of the cashew apple processing industries are generally discarded as waste even though it contains a significant amount of bioactive compounds including phenols. Due to this, the industries are facing issues related to waste disposal and environmental pollution. Extracting and utilizing beneficial phenolic compounds can solve these issues to an extend. However, the scientific research related to the process development for extracting phenolic compounds from cashew apple bagasse is very scarce. The developed green technology with optimum process conditions will be helpful for the industries, researchers, and food scientists to develop different value‐added products enriched with the extracted phenolic compounds.

Quality traits of apple puree treated with conventional, ohmic heating and high-pressure processing

A distinguishing quality or characteristics of apple puree was determined considering the effect of different processing practices: thermal (4 T), ohmic heating (OHM) and high-pressure processing (HPP). In the thermal treatment, the flow rate was set to 1700 L/h and SHP was approximately 40 s; HPP was conducted at 600 MPa for 3 min and ohmic heating at a flow rate of 2000 L/h, at 107 °C (sample preheated from 25 to 60 °C). Effects on colour, viscosity, particle size distribution (PSD), total phenol content (TPC), ascorbic acid content and sensorial quality were comparatively studied. Results showed that a very low reduction of ascorbic acid in HPP is observed. The highest ascorbic acid loss was observed for 4 T and in a lower extent for OHM ascribable to the thermal degradation, as hypothesized for pigments. The TPC content was not changed during processing. The other quality parameters evaluated (viscosity, colour, PSD, turbidity, consistency, sensorial analysis) were affected by treatments, with particular reference to 4 T. This is one of the first study applying commercial industrial-scale equipment’s. Concluding, as compared to 4 T, OHM and HPP demonstrated feasible technologies for the treatment of apple puree, having obtained also a good organoleptic response. Apple puree preparation by means of high-pressure processing, ohmic or mild thermal treatments could imply new opportunities for the apple processing industry in developing more fresh like value-added products with reasonable shelf life.

Biological activity of phenolics enriched extracts from industrial apple pomace

Apple processing industries around the globe generate huge quantity of pomace as waste material, whose sustainable and cost-effective utilization continually being attempted. In general, industrial apple pomace is a conglomeration of different varieties, however, rich in array of inherited nutritional and phytochemical constituents. In present study, aqueous-ethanol, -methanol and -acetone mediated extractions of phenolics from industrial apple pomace was performed. The obtained extracts from respective solvents were further partitioned with ethyl acetate. The phytochemical evaluation of ethyl acetate fractionated aqueous acetone fraction (APA1), aqueous ethanol fraction (APE1) and aqueous methanol fraction (APM1) by high pressure liquid chromatography and electrospray-ionization quadrupole time-of-flight tandem mass spectrometry showed the presence of phloridzin, phloretin, quercitrin and quercetin as major constituents. The cytotoxic effects of APA1, APM1, and APE1 fractions were evaluated against human cancer cell lines i.e. cervical squamous cell carcinoma (SiHa), oral carcinoma (KB) and colorectal adenocarcinoma (HT-29) cell lines. Significant differences were obtained for oral cancer cells in time and dose dependent manner. Cytotoxicity data validated by clonogenic cell survival assay showed significant inhibition of KB cancer cells by APA1 and APE1 after 24 and 36 h. Caspase 3/7 activity of fractions was also found to be increased in time dependent manner. Furthermore, the flow cytometer analysis revealed that KB cells follow apoptotic and necrotic mechanism for cell death after treatment with APA1 and APE1 fractions for 24 and 30 h. Results also showed significant nitric oxide inhibition in lipopolysaccharide– interferon gamma stimulated mice peritoneal macrophages at different concentrations. Present study established that industrial apple pomace indeed has substantial amount of bioactive phenolics that can be bioprocessed to develop variety of health supplements.

Polyphenols from apple skins: A study on microwave-assisted extraction optimization and exhausted solid characterization

Apple processing industry can be improved by the valorization of its residues. Apple skins could be used for the recovery of high added value compounds for the formulation of new antioxidant products (dietary supplements, cosmetics, drugs). In this study, apple skins from Jonagold cultivar were selected as raw material for an optimization study on microwave-assisted process parameters, using green solvents and an inert atmosphere combined to hard operating conditions (long time and high temperature), with the aim to enhance the mass transfer in the extraction process without significant loss in biomolecule activity. Response surface modeling was employed for the experimental planning and multi-variable process optimization. The effect of time, temperature and solvent composition on extraction performances and exhausted solid elemental composition were evaluated. The extract obtained after optimization showed very high extraction yields (50.4 mggallic acid equivalents/gdry biomass; 13.9 mgcatechin equivalents/gdry biomass) and remarkable antiradical properties. Moreover, after the extraction the solid residue exhibited higher carbon content (52.7%) and calorific value (24.6 MJ/kg) than the untreated apple skins.

From Byproduct to Resource: Fermented Apple Pomace as Beer Flavoring.

One of the main struggles of the large-scale apple processing industry is pomace disposal. One solution for this problem is to convert this waste into a resource. Apple pomace could be used as a substrate for lactic acid bacteria and could induce the formation of a more complex aroma profile, making this fermented product an innovative aromatizer for alcoholic beverages, such as beer. In this study, for the first time, the effect of lacto-fermented apple pomace addition in beer was evaluated. Three bacterial strains (Lactobacillus rhamnosus 1473 and 1019, and L. casei 2246) were tested for apple pomace fermentation, and L. rhamnosus 1473 was the strain that best modified the aromatic profile. The addition of fermented apple pomace to beer increased the complexity of the aroma profile, demonstrating the potential of this byproduct as an aromatizer in the alcoholic beverage industry.

Apple Pomace Extract as a Sustainable Food Ingredient.

Apple pomace is a by-product of apple processing industries with low value and thus frequent disposal, although with valuable compounds. Acidified hot water extraction has been suggested as a clean, feasible, and easy approach for the recovery of polyphenols. This type of extraction allowed us to obtain 296 g of extract per kg of dry apple pomace, including 3.3 g of polyphenols and 281 g of carbohydrates. Ultrafiltration and solid-phase extraction using C18 cartridges of the hot water extract suggested that, in addition to the apple native polyphenols detected by ultra-high-pressure liquid chromatography coupled to a diode-array detector and mass spectrometry UHPLC-DAD-ESI-MSn, polyphenols could also be present as complexes with carbohydrates. For the water-soluble polyphenols, antioxidant and anti-inflammatory effects were observed by inhibiting chemically generated hydroxyl radicals (OH•) and nitrogen monoxide radicals (NO•) produced in lipopolysaccharide-stimulated macrophages. The water-soluble polyphenols, when incorporated into yogurt formulations, were not affected by fermentation and improved the antioxidant properties of the final product. This in vitro research paves the way for agro-food industries to achieve more diversified and sustainable solutions towards their main by-products.

Sustainable recovery of grape skins for use in an apple beverage with antiglycation properties

SummaryAn apple puree formulated with red grape skins was developed on pilot scale as a new beverage with antiglycation properties. The addition level of grape skins was selected by a liking test with 70 consumers. The selected formulation was a fibre‐rich source and delivered grape anthocyanins, flavonols and flavanols resulting in ~ twofold higher antiglycation activity than the apple puree. Pasteurisation (3‐D in the target microorganism Alicyclobacillus acidoterrestris) did not affect the antiglycation activity, which decreased by 30% upon sterilisation. Storage for 1 month in the temperature range 15–35 °C affected the contents of anthocyanins, monomeric, dimeric and oligomeric flavanols, while chlorogenic acid, flavonols and dihydrochalcones were stable. About 90% antiglycation activity was retained after one‐month storage at 15 °C. The use of red grape skin as ingredient could represent an opportunity for the apple processing industry to develop a value‐added product.

Utilization of Apple Pomace in the Preparation of Fiber-Enriched Acidophilus Yoghurt

Dried apple pomace contains 36.8% fiber composed of water soluble and insoluble fractions, but is treated as a waste in apple processing industries. The present study was conducted to prepare fiber-enriched yoghurt by using 2.5, 5, 7.5 and 10% apple pomace fiber in whole milk and milk without fiber was kept as the control. All the treatments were inoculated with combined culture (1%) of Lactobacillus acidophilus and Bifidobacterium longum. The yoghurts were evaluated in terms of sensory quality, pH, acidity, total solids and fiber contents. The addition of fiber in yoghurt resulted in a decrease of acidity (0.15–0.09%) and fat contents (1.65–1.59%) with increase in fiber concentration. Further, on the basis of sensory analysis, yoghurt containing 5% apple fiber was judged as the best and hence optimized for preparation of fiber-enriched acidophilus yoghurt with desirable quality and sensory attributes. Practical Applications The diets with high content of fiber have been reported to have a positive effect on health. The importance of food fibers has led to the development of a large and potential market for fiber-rich products and ingredients. Recently, there is a trend to find new sources of dietary fiber that can be used in the food industry. Supplementation has been used to enhance fiber content of foods. Addition of fiber in breakfast cereals, bread, cookies, cakes, yogurt, beverages and meat products has been reported with favorable qualities. The present manuscript was carried out keeping in view the positive effect of fiber on human health.