Extraction of phenolic compounds from organic dried apples: comparison between conventional, microwave- and ultrasound-assisted extraction methods

The aim of this study was to compare a conventional assay with microwave- (MAE) and ultrasound- (UAE) assisted extraction methods on the extraction of phenolic compounds from organic dried apples by evaluating the content in catechin, epicatechin, chlorogenic acid and quercitrin. Samples from two apple varieties (Golden Rush and Topaz) were analyzed. Methanol/water (70:30, v/v) was selected as the solvent mixture for the phenolic compounds extractions. The High Performance Liquid Chromatography coupled to diode array detection (HPLC-DAD) were used for the identification and quantification of the respective phenolic compounds. Qualitative analysis revealed similar phenolic profiles in both apple varieties. Whatever extraction method is used, in both apple varieties chlorogenic acid and epicatechin were present in higher contents compared to catechin and quercitrin with chlorogenic acid being the major contributor. It was found a better extraction of chlorogenic acid, catechin and quercitrin (only for Topaz apple) using conventional process in comparison with MAE and UAE. A higher content of quercitrin was obtained with MAE and UAE compared to conventional method. The content of phenolic compounds in Golden Rush apple was higher than in Topaz apple. Results from this study indicated that conventional extraction can be a more efficient process than MAE and UAE for the extraction of phenolic compounds from organic dried apples

Bioactive compounds and quality parameters in different organic apple varieties

The interest on organic plant-based foods is constantly growing due to their health benefits and ecological importance along with increasing demands of the consumers for quality foods produced sustainably. Organic apples were known to present high content in polyphenols, compounds which are recognized to have multiple biological activities [1]. The aim of this work is to evaluate the variations in quality parameters (firmness, total soluble solids and titratable acidity) and bioactive compounds (anthocyanins and vitamin C) of three organic apple varieties. Organic apple varieties (Gala, Golden and Red Prince) harvested at maturity from an organic farm in August and September 2018 were used for this study. Firmness, total soluble solids and titratable acidity were performed using instrumental analyses [2]. The total anthocyanin content was determined in acidified methanolic extracts by a spectrophotometric method whereas the vitamin C was monitored by HPLC. The firmness and titratable acidity were both significantly higher in Golden variety. The Red Prince variety showed higher total soluble solids and total anthocyanin content than Gala and Golden varieties, what recommends their use for processing immediately after harvesting or in the first few weeks, while the Golden variety can be stored under controlled conditions for further processing. The data also pointed that the Golden variety have high vitamin C content as well as higher firmness and titratable acidity values compared to the red apple varieties. From these results it can be concluded that quality parameters and bioactive compounds of organic apples are generally influenced by the variety

Changes in carotenoid content of organic tomato powders depending in drying parameters

There are known that the functionalities of powdered natural ingredients from food products are strongly dependent on the chemical composition. The pre-treatment and type of drying can cause changes in amounts of nutritional compounds (vitamins, carotenoids, polyphenols) of fruits and vegetables. Therefore, this study investigates the effects of different drying treatments (hot air at 40 and 70 °C) on the carotenoid content of powders obtained from juice and blanched fresh organic tomatoes

DRYING TREATMENT EFFECTS ON ANTHOCYANINS OF ORGANIC RASPBERRY (CV. HERITAGE) FRUIT

The aim of this study is to compare the effects of some drying processes (hot-air drying and freeze drying) on total anthocyanin content (TAC) for organic raspberry (cv. Heritage) fruits as measured by spectrophotometric method and UPLC technique. The total anthocyanin content was determined in powders obtained from fruits and juice of organic raspberry dried in a hot-air dehydrator at 70 ºC and a freeze dryer at –55 ºC for 45 h. Qualitative analysis revealed the similar anthocyanin profiles in all raspberry powders and showed a clear anthocyanin pattern with the presence of two major compounds. In both fruit and juice of organic raspberry, freeze drying produced a better extraction of the total anthocyanin content either by spectrophotometric method or UPLC and this could be attributed to the thermal degradation and/or oxidation of these compounds during hot-air drying. As matter of fact, the highest total anthocyanin contents were found in milled to juice organic raspberries compared to fresh dried fruits. The results presented in this work indicate that the most appropriate drying method in terms of the anthocyanin content is freeze drying. However, the detailed qualitative analysis of the raspberry powders should help understanding the effects of different drying treatments

A probabilistic design for practical homomorphic majority voting with intrinsic differential privacy

As machine learning (ML) has become pervasive throughout various fields (industry, healthcare, social networks), privacy concerns regarding the data used for its training have gained a critical importance. In settings where several parties wish to collaboratively train a common model without jeopardizing their sensitive data, the need for a private training protocol is particularly stringent and implies to protect the data against both the model's end-users and the other actors of the training phase. In this context of secure collaborative learning, Differential Privacy (DP) and Fully Homomorphic Encryption (FHE) are two complementary countermeasures of growing interest to thwart privacy attacks in ML systems. Central to many collaborative training protocols, in the line of PATE, is majority voting aggregation. Thus, in this paper, we design SHIELD, a probabilistic approximate majority voting operator which is faster when homomorphically executed than existing approaches based on exact argmax computation over an histogram of votes. As an additional benefit, the inaccuracy of SHIELD is used as a feature to provably enable DP guarantees. Although SHIELD may have other applications, we focus here on one setting and seamlessly integrate it in the SPEED collaborative training framework from \cite{grivet2021speed} to improve its computational efficiency. After thoroughly describing the FHE implementation of our algorithm and its DP analysis, we present experimental results. To the best of our knowledge, it is the first work in which relaxing the accuracy of an algorithm is constructively usable as a degree of freedom to achieve better FHE performances

USE OF ESSENTIAL OILS AS GREEN BIOPESTICIDES

In recent years, there has been a growing interest in the application of herbal products, especially essential oils (EOs) in agriculture, as an alternative to the use of synthetic pesticides, for healthy crops and environmentally sustainable production systems. This was the main reason why the properties of EOs as natural pesticides for their promotion and use in organic farming were evaluated. EPA (Environmental Protection Agency) defines biopesticide as a safer product, with a lower persistence in the environment, biodegradable, less toxic to non-target organisms, less likely to contaminate soil and groundwater. Many EOs obtained from medicinal plants have a wide range of activities against harmful insects, bacteria and phytopathogenic fungi, weeds. Their action varies from insecticidal activities, repellents, antifeedants, growth regulation, etc. This review presents the most effective biopesticides based on EOs obtained from medicinal plants and the future development prospects of this industry.Â

Practical Multi-Key Homomorphic Encryption for More Flexible and Efficient Secure Federated Aggregation (preliminary work)

In this work, we introduce a lightweight communication-efficient multi-key approach suitable for the Federated Averaging rule. By combining secret-key RLWE-based HE, additive secret sharing and PRFs, we reduce approximately by a half the communication cost per party when compared to the usual public-key instantiations, while keeping practical homomorphic aggregation performances. Additionally, for LWE-based instantiations, our approach reduces the communication cost per party from quadratic to linear in terms of the lattice dimension

Qualitative features of organic tomatoes

In recent years, the organic sector has put significant efforts in the development of clear definitions for gentle and quality oriented processing of plant based foodstuffs to supplement existing regulations. Concrete quality standards for different types of processing are under development in several CoreOrganic Plus projects. However, there is still a significant need for development of a Code of Practice. Quality of a product and sustainability of production depend on the cumulative impacts of each processing step in the food chain, as well as the quality of the raw material. With increasing demands by the consumers who expect high quality foods produced sustainably and preferably regionally (SusOrganic consumer survey), pressure on the producers is growing as this requires skilled and qualified agri-food practitioners, professionals and manufacturers to be able to deliver the best quality at affordable prices and the lowest environmental impact possible

Natural Compounds for Wound Healing

Many plants or plant-derived compounds with high levels of antioxidants and anti-inflammatory, immunomodulatory, and antimicrobial properties could be of great benefit for wound healing. Several studies have documented the use of plant extracts for the development of bioactive wound dressings. The purpose of this chapter is to give an update about the vegetal and bee products, which can be used as bioactive substances in wound dressings or in other formulations for wound healing. The adverse effects of plant and bee extracts, such as contact allergies, are also presented. In order to better exploit the huge reservoir of pharmacologically active plant-derived compounds and extracts, standardized methodology and clinical trials are necessary to give more concrete evidence supporting the use of traditional medicine in wound management

RandSolomon: Optimally Resilient Random Number Generator with Deterministic Termination

Multi-party random number generation is a key building-block in many practical protocols. While straightforward to solve when all parties are trusted to behave correctly, the problem becomes much more difficult in the presence of faults. This paper presents RandSolomon, a partially synchronous protocol that allows a system of N processes to produce an unpredictable common random number shared by correct participants. The protocol is optimally resilient, as it allows up to f = ?(N-1)/3? of the processes to behave arbitrarily, ensures deterministic termination and, contrary to prior solutions, does not, at any point, expect faulty processes to be responsive