The Mediterranean diet includes virgin olive oil (VOO) as the main fat and olives as snacks. In addition to providing nutritional and organoleptic properties, VOO and the fruits (olives) contain an ...extensive number of bioactive compounds, mainly phenolic compounds, which are considered to be powerful antioxidants. Furthermore, olive byproducts, such as olive leaves, olive pomace, and olive mill wastewater, considered also as rich sources of phenolic compounds, are now valorized due to being mainly applied in the pharmaceutical and nutraceutical industries. The digestive system must physically and chemically break down these ingested olive-related products to release their phenolic compounds, which will be further metabolized to be used by the human organism. The first purpose of this review is to provide an overview of the current status of in-vitro static digestion models for olive-related products. In this sense, the in-vitro gastrointestinal digestion methods are widely used with the following aims: (i) to study how phenolic compounds are released from their matrices and to identify structural changes of phenolic compounds after the digestion of olive fruits and oils and (ii) to support the functional value of olive leaves and byproducts generated in the olive industry by assessing their health properties before and after the gastrointestinal process. The second purpose of this review is to survey and discuss all the results available to date.
Moi, as he liked to be called by family and friends, passed away on February 14th in Jerusalem, where he had enjoyed the last years of his life in the loving care of his daughter Jacqueline. At the ...age of 92, he now rests in peace in the Mount of Olives Cemetery. After Otto Mittelstaedt (1919-2000) and Otto Tinschert (1915-2006), Guatemala’s orchidology has now lost the third of its founding fathers.
This comprehensive review points out the major developments on the recovery of bioactive compounds of olive by-products, intending innovative food applications and enhanced technological functions. ...Nutritional and sensorial factors influencing consumers' acceptance are also discussed. Besides being an economic burden for producers, olive oil by-products also represent a severe environmental problem. Simultaneously, these are rich in bioactive compounds, which are remarkable added-value ingredients for other industries. New applications have been focused in ameliorating the food nutritional profile, replacing or improving technological properties/functions of food additives, and extending food products shelf life. Eco-friendly food packaging is also a promissory application field. The improvement of nutritional functionality and sensory quality of enriched food is another challenging task. Despite the large chemical characterization of olive products and olive oil processing by-products, further research is still needed to fully understand the potential of this valuable raw material.
High added-value ingredients can be obtained by recovering bioactive compounds from olive by-products. Those can be used by food industry to improve food product nutritional profile and/or with a technological functionality. This review presents food applications developed with ingredients and bioactive compounds derived from olive processing by-products. It aims to be useful for food industries and other agro-industrial stakeholders in order to encourage and expand the utilization of olive by-products in the development of innovative food products.
•There has been a great by-products generation with the growth of olive oil production.•Olive by-products have high content in bioactive compounds.•Olive by-products have high potential to be used in food applications.•Food functional properties are improved using olive by-products as ingredients.•Food technological properties are improved using olive by-products as ingredients.
In this work, the effect of different treatments using selected combinations of chloride salts (NaCl, KCl, CaCl2, MgCl2) in fermentation brine to assess the safety, quality, and nutritional value of ...the Spanish style cv. Chalkidiki green table olives spontaneously fermented is studied. Examination of safety parameters (bacteria/yeasts, pH, acidity) and changes in olive color and texture characteristics in brines during fermentation, and in mineral content of olives upon storage up to 12 months, is conducted using appropriate methods. Sensory evaluation takes place in certain cases. Among the tested salt combinations, those of 4.08% NaCl, 2.8% KCl, 1% CaCl2, and 0.12% MgCl2 (w/v) are found to be the most effective regarding safety, color, texture, and taste. Findings support that Spanish style cv. Chalkidiki green olives can be spontaneously fermented in reduced NaCl content brine. The 50% lower NaCl content of the fermented olives compared with that in traditionally fermented ones suggests that reformulation of cv. Chalkidiki green table olives by safe intervention is feasible.
Practical Applications: cv. Chalkidiki green table olives are of high importance for the Greek economy. Traditionally they are spontaneously fermented in NaCl brine (8% w/v). Partial replacement of NaCl content with other salts in such a line results in a product acceptable in terms of safety and quality characteristics. The Greek table olive industry may profit from the findings in an attempt to remodel the traditional spontaneous fermentation in green olive processing according to international dietary guidelines.
Spontaneous fermentation of Spanish style cv. Chalkidiki green table olives in reduced NaCl brines is feasible in terms of safety and quality aspects.
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•Industrial-scale production of Spanish-style & natural cv. Chalkidiki green olives.•All products were safe with high nutritional value and desirable sensory attributes.•Metabolite ...profile of polar extracts from olives & brines was processing-depended.•Lye treatment absence maintained the triterpenic acids content in olives.•Reducing NaCl level in processing led to lower Na in flesh.
Table olives are among the most popular fermented foods and cv. Chalkidiki green table olives are particularly popular in both Greek and international markets. This work aimed at comparatively investigating the effect of processing method on the production of Spanish-style and natural cv. Chalkidiki green olives during fermentation and 12-month storage in brines with different chloride salts composition (NaCl, KCl, CaCl2) at industrial scale. All delivered products were safe with satisfactory color and texture characteristics. Employment of UPLC-HRMS revealed differences in metabolites’ profile of polar extracts from olives and brines between the processing methods. Τhe application of alkali treatment drastically decreased the content of hydroxytyrosol and tyrosol in drupes, still an essential amount (1037–2012 and 385–885 mg/kg dry flesh, respectively) of these health-promoting phenolic compounds was retained in all products, even after storage. Noteworthy, fermentation of natural olives in brine (5 % NaCl) yielded in products with significantly lower Na levels in olive flesh (1.7 g/100 g), followed by Spanish-style olives fermented in low (4 %) and high (8 %) NaCl brines (2.7 and 5.2 g Na/100 g, respectively), supporting the efforts toward the establishment of table olives as functional food. Moreover, maslinic and oleanolic acids content was 1.5–2-fold higher in the natural table olives compared to the Spanish-style ones owing to the detrimental effect of alkali treatments. The processing method did not exert a differential effect on α-tocopherol content of olives. Sensory analysis indicated that all the final products were acceptable by consumers, with a slight preference for Spanish-style green olives fermented in brines with 50 % lower NaCl content. Present findings could be beneficial to the ongoing endeavor directed for the establishment of table olives as a source of bioactive compounds that concerns both industrial and scientific communities.
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•A portfolio of processes is available to valorize olive biomass.•This includes conversion to energy, gas, fuels, and/or a wide range of bioproducts.•Examples of biorefinery schemes ...based on olive biomasses are described.•The industrial deployment of the biorefinery facilities is still missing.
Olive oil is a characteristic product of Mediterranean countries, and its production is rapidly expanding to many other regions due to the health benefits attributed to the consumption of high-quality olive oil. Taking into account that the oil content is, on average, only 20% by weight of olives, a great amount of biomass, including leaves, pits, and pomace, is produced in the mill along with the main product. Moreover, the pruning of olive trees and the production of the olive pomace also generates a great amount of biomass. Currently, the usual practices for disposal of these different biomasses do not take advantage of the wide range of products that can be produced from them. This work summarizes the most relevant practices considering both the bioprocesses studied for the exploitation of the olive-derived biomass and the potential products obtained. The integration of processes in a single facility, i.e., the concept of a biorefinery based on olive-derived biomass, is also reviewed, including technoeconomic and environmental assessment.
Cultivation of olive trees and olive oil production have been considered as a legacy for the Mediterranean region. This custom represents a very important benefit for many nations in terms of wealth ...and health. However, huge amounts of by-products and waste are generated during olive oil production. This represents a serious environmental impact on land and water bodies if not properly handled. Olive oil extraction generates two waste streams, a solid waste called pomace and olive mill wastewater (OMWW), which has been considered as highly pollutant and phytotoxic waste. These wastes have high disposal costs and predominantly generated from small-scale enterprises that have limited financial resources to treat them properly before discharge to the environment. Besides being a serious environmental problem, OMWW has potential economic value that remains to be utilized such as: fertilizers, valuable antioxidants agents and fatty acids needed in human diet. Also, Olive pomace is a valuable renewable energy source with an energy density of 23 MJ/kg and has become an inexpensive alternative for fossil fuels. Aiming at adding value to the olive production sectors and potential valorization options for byproducts in the MENA region, international practices applied in olive mills wastes management’s and treatment methods used in major oil producing countries are presented.
A comprehensive effort was devoted to exploring, collecting and characterizing the local Maltese olive germplasm, often represented by ancient, monumental trees and by plants of uncertain origin. SSR ...and cp-SSR analysis of all samples enabled the identification of 46 genotypes and establishment of the correspondence between ancient trees, main local varieties and other Mediterranean cultivars. The application of plastid markers enabled identification of two lineages among Maltese genotypes, with more than 50% represented by lineage E2. Twenty-nine cases of grafting were identified among the various genotypes and lineages. In most cases, E1 canopies were grafted on E2 rootstocks, but reverse cases were also observed. The phylogenetic study of Maltese genotypes, together with hundreds of cultivars from the Mediterranean Basin and beyond, highlights the richness of Maltese olive diversity and drawing attention to the genetic similarity of some Maltese olive genotypes with neighboring Italian and Algerian varieties. These results underline the long-lasting presence of the olive in the country, contributing to the reconstruction of its phylogeny and demonstrating a possible autochthonous origin of many samples. Some still-living ancient trees are at serious risk of extinction due to abandonment, urban expansion and environmental threats. This study supports the preservation of the Maltese olive germplasm and highlights its importance as a rich genetic source to face new agronomical challenges and future climatic constraints.
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