A review of the polyphenols extraction from apple pomace: novel technologies and techniques of cell disintegration

Increasing the Content of Bioactive Compounds in Apple Juice Through Direct Ultrasound-Assisted Extraction from Bilberry Pomace

The increasing trend of diet-related chronic diseases has stimulated research into developing new food products and beverages with health-promoting potential. At the same time, new resources, including plant by-products, are currently being investigated as a sustainable source of bioactive compounds. In this context, the present study focused on the enrichment of apple juice with anthocyanins and other phenolic compounds by direct ultrasound-assisted extraction (UAE) from bilberry pomace. Response surface methodology combined with a Box-Behnken design was used to find the optimal extraction conditions for maximizing the total anthocyanin content (TAC), total phenolic content (TPC) and DPPH radical scavenging activity (RSA) in the enriched apple juices and to characterize their phenolic profile as influenced by the extraction temperature. UAE from 15% bilberry pomace during 15 min in apple juice at 80 °C resulted in the highest TAC (262.73 mg CGE/L), TPC (1700.91 mg GAE/L) and RSA (8.93 mmol Trolox/L) of the enriched apple juice. The chromatographic polyphenolic profile of the control and enriched juices showed that, besides anthocyanins, phenolic acids (chlorogenic, gallic, caffeic, 3-hydroxybenzoic, p-coumaric, ellagic and protocatechuic acids) and flavonoids (epigallocatechin and catechin) were extracted from the bilberry pomace directly in the apple juice, while the extraction temperature differently impacted the content of individual phenolic compounds.

An innovative technique for the extraction and stability of polyphenols using high voltage electrical discharge: HVED-Assisted Extraction of Polyphenols

Polyphenols are the main group of phytochemicals with several biological activities. Due to the adverse effects of conventional solvent extraction methods, innovative extraction techniques have been used as alternatives to overcome these problems. High voltage electric discharge (HVED) is an eco-friendly innovative extraction technique based on the phenomenon of electrical breakdown in water. This technique induces physical and chemical processes, leading to product fragmentation, cellular damage, and liberation of bioactive compounds. HVED treatment can extract polyphenols at lower temperatures and shorter times than the conventional solvent extraction methods. This review summarizes the effect of HVED processing parameters on the recovery and stability of polyphenols from plant sources. Hydroethanolic solutions improve the HVED-assisted extraction of polyphenols compared to water. Moreover, acidic solvents are suitable for the high recovery and protection of polyphenols during electric discharges. This study revealed the efficacy of the HVED technique in extracting polyphenols for their utilization in the food and pharmaceutical industries.

Monitoring and Risk Assessment of Multi-Pesticide Residues in Apples: A Focus on Consumer Safety

Pesticide residues in human diets pose significant health hazards, particularly for vulnerable populations such as infants and children. This study aimed to determine pesticide residues in apples and to assess the cumulatively chronic risk posed to adult and child consumers from simultaneous exposure to multiple residues. During the 2022-2023 harvest seasons, 100 apple samples from Turkey were analyzed for the presence of 225 different pesticide residues. Pesticide extraction was performed using the QuEChERS method, followed by detection through liquid chromatography coupled with tandem mass spectrometry. Fifteen distinct pesticides (ten insecticides and five fungicides) were detected in 64 out of the 100 apple samples analyzed. Eleven samples contained pesticide residues that exceeded the maximum residue limit (MRL) set by the Turkish Food Codex and the European Union. Thiophanate-methyl was the most frequently detected pesticide (34%) in apples, with concentrations ranging from 0.012 to 0.108 mg kg-1, all of which were well below the MRL of 0.5 mg kg-1. Other commonly detected residues included chlorantraniliprole (28%), acetamiprid (24%), sulfoxaflor (22%), bifenazate (18%), indoxacarb (13%), diflubenzuron (12%), and carbendazim (10%). Under a worst-case scenario, the hazard index (HI) values for adults and children were 0.85% and 2.60%, respectively, indicating that these values remain significantly below the risk threshold of 100%, suggesting no associated health risks from apple consumption. However, regular monitoring of pesticide residues in fresh fruits and vegetables remains critically important.

A review of the polyphenols purification from apple products

Apple polyphenols are one of the major bioactive compounds in apple products and have strong anti-inflammatory effects and the ability to prevent chronic diseases with health benefits. The development of apple polyphenol products is dependent on the extraction, purification and identification of apple polyphenols. The extracted polyphenols need to be further purified to improve the concentration of the extracted polyphenols. This review, therefore, presents the studies on the conventional and novel methods for polyphenols purification from apple products. The different chromatography methods, as one of the most widely used conventional purification methods, for polyphenol purification from various apple products are introduced. In addition, the perspective of the adsorption-desorption process and membrane filtration technique in enhancing the purification of polyphenols from apple products are presented in this review. The advantages and disadvantages of these purification techniques are also discussed and compared in depth. However, each of the reviewed technologies has some disadvantages that need to be overcome, and some mechanisms need to be further identified. Therefore, more competitive polyphenols purification techniques need to emerge in the future. It is hoped that this review can provide a research basis for the efficient purification of apple polyphenols, which can facilitate their application in various fields.

Deep Learning in Precision Agriculture: Artificially Generated VNIR Images Segmentation for Early Postharvest Decay Prediction in Apples

Food quality control is an important task in the agricultural domain at the postharvest stage for avoiding food losses. The latest achievements in image processing with deep learning (DL) and computer vision (CV) approaches provide a number of effective tools based on the image colorization and image-to-image translation for plant quality control at the postharvest stage. In this article, we propose the approach based on Generative Adversarial Network (GAN) and Convolutional Neural Network (CNN) techniques to use synthesized and segmented VNIR imaging data for early postharvest decay and fungal zone predictions as well as the quality assessment of stored apples. The Pix2PixHD model achieved higher results in terms of VNIR images translation from RGB (SSIM = 0.972). Mask R-CNN model was selected as a CNN technique for VNIR images segmentation and achieved 58.861 for postharvest decay zones, 40.968 for fungal zones and 94.800 for both the decayed and fungal zones detection and prediction in stored apples in terms of F1-score metric. In order to verify the effectiveness of this approach, a unique paired dataset containing 1305 RGB and VNIR images of apples of four varieties was obtained. It is further utilized for a GAN model selection. Additionally, we acquired 1029 VNIR images of apples for training and testing a CNN model. We conducted validation on an embedded system equipped with a graphical processing unit. Using Pix2PixHD, 100 VNIR images from RGB images were generated at a rate of 17 frames per second (FPS). Subsequently, these images were segmented using Mask R-CNN at a rate of 0.42 FPS. The achieved results are promising for enhancing the food study and control during the postharvest stage.

Identification and Quantification of Polyphenols in Croatian Traditional Apple Varieties

Apples and apple-based products are particularly interesting due to being a good source of polyphenols in an everyday diet. Recently there has been increased interest in the preservation of traditional apple varieties due to studies that suggest that traditional apple varieties have a higher content of polyphenols and antioxidant activity compared to commercial varieties. This study shows that traditional apple varieties contain higher concentration of polyphenolic compounds than conventional ones, such as chlorogenic acid (1.29-456 mg/kg dw), catechin (0.70-312 mg/kg dw), epicatechin (1.75-244 mg/kg dw), procyanidin B1 + B2 (4.08-358 mg/kg dw) and quercetin-3-glucoside (0.96-231 mg/kg dw). This research underlies the great potential of traditional apple varieties as a source of natural antioxidants and polyphenolics.

An appealing review of industrial and nutraceutical applications of pistachio waste

Pistachio (Pistacia vera L.) is consumed in almost every part of the world enclosed in shells that are thrown out in baskets. Similarly, hulls separated from pistachio are discarded as waste in food processing industries. These waste materials contain functional constituents having immense industrial and nutraceutical applications. This review article summarizes the scientific investigations regarding the functional constituents and bioactive compounds in pistachio shells (PSs) and pistachio hulls (PHs). It also highlights the nutraceutical potential exhibited by functionally active compounds as well as their potential applications in various industries including nutraceutical, medicinal, and feed industries together with biosynthetic development of useful products and wastewater treatment. Pistachio waste (PW) comprising PS and PH is a rich source of various bioactive compounds. PS is full of lignin, cellulose, and hemicellulose. PH is an excellent source of carbohydrates (80.64 ± 0.98%) (including glucose, galactose, rhamnose, arabinose, xylose, mannose, galacturonic acid) as well as ash (6.32 ± 0.26%) and proteins (1.80 ± 0.28%) with small amounts of fats (0.04 ± 0.005%). Owing to its composition, PW can be beneficial in many nutraceuticals, including antioxidation, cytoprotection, anti-obesity, anti-diabetic, anti-melanogenesis, neuroprotection, anti-cancer, anti-mutagenesis, anti-inflammation, and anti-microbial. The waste materials have vast applications in the food industry, such as bio-preservation of oils and meat products, prevention of enzymatic browning in fruits, vegetables, and mushrooms, development of functional cereal and dairy products, production of food enzymes, emulsions, and manufacturing of biodegradable films for food packaging. The use of these waste products to develop and design novel functional foods with improved quality is important for both food industries and food sustainability.

Agri-Food Waste from Apple, Pear, and Sugar Beet as a Source of Protective Bioactive Molecules for Endothelial Dysfunction and Its Major Complications

Endothelial damage is recognized as the initial step that precedes several cardiovascular diseases (CVD), such as atherosclerosis, hypertension, and coronary artery disease. It has been demonstrated that the best treatment for CVD is prevention, and, in the frame of a healthy lifestyle, the consumption of vegetables, rich in bioactive molecules, appears effective at reducing the risk of CVD. In this context, the large amount of agri-food industry waste, considered a global problem due to its environmental and economic impact, represents an unexplored source of bioactive compounds. This review provides a summary regarding the possible exploitation of waste or by-products derived by the processing of three traditional Italian crops-apple, pear, and sugar beet-as a source of bioactive molecules to protect endothelial function. Particular attention has been given to the bioactive chemical profile of these pomaces and their efficacy in various pathological conditions related to endothelial dysfunction. The waste matrices of apple, pear, and sugar beet crops can represent promising starting material for producing "upcycled" products with functional applications, such as the prevention of endothelial dysfunction linked to cardiovascular diseases.