Ultrasound assisted extraction of bioactive compounds

U današnje vrijeme, traže se alternative klasičnim, toplinskim metodama procesiranja hrane. Jedna od novijih tehnika jest tehnika minimalnog procesiranja hrane, pod kojom podrazumijevamo i tretiranje ultrazvukom. Ultrazvučna tehnologija može biti vrlo korisna kod minimalnog procesiranja hrane, jer je prijenos akustične energije kroz proizvod brz i cjelovit, što omogućava redukciju ukupnog vremena obrade, te nižu potrošnju energije. Djelovanjem industrije nastaje sve više otpadnih materijala, a u želji očuvanja globalnih resursa i poboljšanja energetske efikasnosti, istražuju se načini ekstrakcije aktivnih tvari iz bioloških izvora sa ciljem primjene u prehrambenoj i farmaceutskoj industriji te medicini. Metodom ultrazvučne ekstrakcije bioaktivnih tvari nastoji se smanjiti upotreba otapala ili potpuno izbjegavati njihova upotreba. Ograničava se povišenje temperature tijekom tretmana te se dobiva veći prinos ekstraktivnih, bioaktivnih tvari. U ovom radu prikazan je mehanizam ultrazvučno inducirane ekstrakcije te primjeri ekstrakcije aktivnih tvari iz različitih biljnih materijala. Ultrazvuk može poboljšati postojeće mehanizme ekstrakcije te omogućiti nove mogućnosti komercijalne ekstrakcije. Primjena (ultrazvučne kemije) sonokemije nudi bolji prinos željenih komponenti, povećanu stopu ekstrakcije te postizanje smanjenja vremena tretiranja.Many novel and innovative techniques are nowadays researched and explored in order to replace or improve classical, thermal processing technologies. One of newer technique is technique of minimal food processing, under what we assume ultrasound processing. Ultrasound technology can be very useful for minimal food processing because transmission of acoustic energy through product is fast and complete, which allows reduction in total processing time, and therefore lower energy consumption. Industrial processing is growing more and more waste products, and in desire of preservation of global recourses and energy efficiency, several ways of active compounds extraction techniques are now explored. The goal is to implement novel extraction techniques in food and pharmaceutical industry as well in medicine. Ultrasound assisted extraction of bioactive compounds offers increase in yield, and reduction or total avoiding of solvent usage. Increase in temperature of treatment is controlled and restricted, thereby preserving extracted bioactive compounds. In this paper, several methods of ultrasound assisted extraction of bioactive compounds from plant materials are shown. Ultrasound can improve classic mechanisms of extraction, and thereby offer novel possibilities of commercial extraction of desired compounds. Application of sonochemistry (ultrasound chemistry) is providing better yield in desired compounds and reduction in treatment time

Three Pillars of Novel Nonthermal Food Technologies:Food Safety, Quality, and Environment

This review gives an overview of the impact of novel nonthermal food technologies on food safety, on quality, and on the environment. It confirms that research in this field is mainly focused on analyzing microbial and/or chemical aspects of food safety. However, recent research shows that in spite of various food safety benefits, some negative (quality oriented) features occur. Finally, this paper shows the necessity of analyzing the environmental dimension of using these technologies

Ponašanje potrošača i motivi odabira mliječnih napitaka na području Kvarnera: pilot-studija

Since food choice is always a unique and personal experience, consumer behaviour is important for food manufacturers and marketers in term of product success. Due to the beneficial healthprotective effects of dairy beverages, this market segment is very innovative and fast-growing. The aim of this pilot-study was to examine the consumption patterns, purchasing behaviour and motives for selection of dairy beverages. The sample of this study included 114 participants (44 males and 70 females) which were interviewed face-to-face at the entrance of 5 shopping centres. The survey instrument consisted of closed questions regarding habits of consumption, purchasing habits and motives for selection of dairy beverages. Gender specific differences were tested. The results obtained have shown that females consumed more milk and milk drinks (p<0.001) and fermented milk drinks (p=0.002) than males. The consumption of whey-based beverages was sporadical in both genders. Females in higher percentage purchase low-fat dairy beverages (p=0.043), while males exhibited a higher level of loyalty to a certain product (p=0.034). Sensory appeals were the most important motivational factor for both genders. Brand was ranked second for males (p<0.001) and health aspect for females. The products’ origin was ranked third, while price was ranked fifth for both genders. The results obtained could be useful to researchers and dairy market sector in developing and promoting a group of dairy beverage products based on innovations and health.S obzirom da je odabir hrane individualna značajka pojedinca, za uspjeh proizvoda na tržištu nužno je da i proizvođači i prodavači poznaju ponašanja potrošača. Zahvaljujući pozitivnim učincima na zdravlje, mliječni napici predstavljaju inovativni i brzorastući tržišni segment. Cilj ove pilot-studije bio je ispitati navike konzumacije, ponašanje pri kupovini i motive odabira među potrošačima mliječnih napitaka. Promatrana skupina uključivala je 114 ispitanika (44 muškarca i 70 žena) koji su usmeno intervjuirani na ulazu pet trgovačkih centara. Korišteni upitnik sastojao se od zatvorenih pitanja koja su uključivala navike konzumacije, ponašanje pri kupovini i motive odabira mliječnih napitaka. Ispitivane su također razlike obzorom na spol. Dobiveni rezultati pokazali su da žene više konzumiraju mlijeko i mliječne napitke (p<0,001) te fermentirane mliječne napitke (p=0,002). Konzumacija napitaka na bazi sirutke bila je sporadična kod oba spola. Žene u većem broju konzumiraju mliječne napitke sa smanjenim sadržajem masti (p=0,043), dok muškarci pokazuju veću lojalnost pojedinom tipu proizvoda (p=0,034). Organoleptičke značajke predstavljaju za oba spola najvažniji motiv odabira. Na drugom mjestu je za muškarce brend (p<0,001) a za žene učinci na zdravlje. Podrijetlo proizvoda je na trećem mjestu, dok je cijena na petom mjestu. Dobiveni rezultati mogu biti korisni za istraživače, ali i za sektor mliječne industrije kako u promociji postojećih tako i u razvoju novih mliječnih napitaka baziranih na inovativnosti i učincima na zdravlje

Usporedba kemijskog sastava, reoloških i senzorskih svojstava kefira proizvedenog primjenom kefirnih zrnaca i starter kulture

The main objective of this study was to compare chemical, rheological and sensory characteristics of kefir produced by using kefir grains and kefir starter. The intent was also to investigate whether it is plausible to use a combined inoculum (kefir grains and starter) in order to obtain a kefir with improved characteristics in terms of sensory and rheological characteristics. Kefir samples were produced at 25 °C and 35 °C by using starter culture XPL-1, kefir grains and their combinations. All of the produced kefir samples were analysed for acidity, total dry matter, ethanol content, syneresis, viscosity and were sensory evaluated by a specially trained panel. There were no significant differences considering the total dry matter, syneresis, ethanol content and acidity. Excess viscosity was observed in samples produced by starter culture at 35 °C, which was described as untypical, yoghurt like and unsatisfactory by a sensory panel. The sample produced at 25 °C by equal amounts of kefir grains and starter culture received the highest scores at sensory evaluation and showed the best potential for optimizing the further use. Further investigations need to focus on examining kefir properties during the storage period, especially regarding microbiological and sensory properties, ethanol content and texture profile.Cilj ovog rada bio je usporediti kemijski sastav, reološka i senzorska svojstva kefira proizvedenog pomoću kefirnih zrnaca i starter kulture. Osim toga, namjera je bila ispitati i opravdanost uporabe inokuluma dobivenog kombinacijom kefirnih zrnaca i starter kulture u svrhu postizanja kefira poboljšanih senzorskih i reoloških svojstava. Uzorci kefira proizvedeni su pri 25 °C i 35 °C primjenom starter kulture XPL-1, kefirnih zrnaca i njihove međusobne kombinacije. Svim proizvedenim uzorcima određivana je kiselost, ukupna suha tvar, udio etanola, sinereza, viskoznost i senzorska svojstva. Pri tom nisu zamijećene značajnije razlike u ukupnoj suhoj tvari, sinerezi, udjelu etanola i kiselosti. Međutim, u uzorcima proizvedenim pri temperaturi fermentacije 35 °C utvrđena je prekomjerna viskoznost koju je senzorski panel okarakterizirao kao netipičnu, svojstvenu jogurtu i nezadovoljavajuću. Uzorak proizveden fermentacijom pri temperaturi od 25 °C primjenom inokuluma sastavljenog od podjednakih dijelova starter kulture i kefirnih zrnaca najbolje je ocijenjen od strane senzorskog panela te je pokazao najveći potencijal za optimiranje i daljnju uporabu. Buduća istraživanja trebala bi se usredotočiti na ispitivanje svojstava kefira tijekom skladištenja, prije svega u pogledu mikrobioloških i senzorskih svojstava, udjela etanola i teksture

Utjecaj inovativnih tehnika na reološka i termofizička svojstva modelnih sustava proteina sirutke i guar gume

The aim of this study was to examine the effect of high-power ultrasound (US) and highpressure processing (HP) on model systems composed of whey protein concentrate (WPC) and whey protein isolate (WPI) with or without guar gum addition. This kind of systems can be found in food production industry so the aim was to use novel food processing technologies to be utilized as a method for products development. Aqueous suspensions (10 g kg-1) of powdered whey proteins were treated with either ultrasound or high pressure. The treatment conditions were as follows: US: frequency of 30 kHz, for 5 and 10 min; HP: pressure intensity 300-600 MPa, for 5 and 10 min. Rheological and thermophysical properties were analyzed after guar gum addition (0.5 g kg-1). Ultrasound treatment showed a significant influence on all examined properties through protein denaturation caused by cavitation and microstreaming effects. High pressure caused significant increase in viscosity and consistency coefficients of model systems with and without guar addition. Significant decrease of initial freezing and initial thawing temperature was observed in all samples. With this research the direct influence of ultrasound and high-pressure treatment on the rheological and thermophysical properties of whey protein isolate and concentrate model systems with or without guar gum was demonstrated.Svrha ovog istraživanja je ispitati utjecaj ultrazvuka visoke snage (US) i procesiranja visokim tlakom (HP) na modelne sustave sastavljene od koncentrata proteina sirutke (WPC) i izolata proteina sirutke (WPI) sa ili bez dodatka guar gume. Ovi sustavi mogu se naći u prehrambenoj industriji, tako da je cilj ovog rada koristiti nove tehnike procesiranja kao metodu koja se može koristiti u razvoju novih proizvoda. Vodene suspenzije (10 g kg-1) proteina sirutke su tretirane s ultrazvukom ili visokim hidrostatskim tlakom. Uvjeti tretiranja su bili sljedeći: US: frekvencija od 30 kHz, kroz 5 i 10 min.; HP: intenzitet tlaka 300-600 MPa, kroz 5 and 10 min. Reološka i termofizička svojstva analizirana su nakon dodatka guar gume (0,5 g kg-1). Ultrazvučnim tretmanom pokazan je značajan utjecaj na sva ispitivana svojstva kroz denaturaciju proteina sirutke uzrokovanu putem kavitacije i učinaka mikrostrujanja. Tretman visokim hidrostatskim tlakom uzrokovao je značajno povećanje viskoznosti i koeficijenta konzistencije modelnih sustava sa ili bez dodatka guar gume. Također, zamijećeno je značajno smanjenje početne temperature smrzavanja i odmrzavanja kod svih uzoraka. S ovim istraživanjem pokazan je direktan utjecaj tretmana ultrazvukom i visokim hidrostatskim tlakom na reološka i termofizikalna svojstva modelnih sustava izolata i koncentrata proteina sirutke sa ili bez dodatka guar gume

Utjecaj inovativnih tehnika na reološka i termofizička svojstva modelnih sustava proteina sirutke i guar gume

The aim of this study was to examine the effect of high-power ultrasound (US) and highpressure processing (HP) on model systems composed of whey protein concentrate (WPC) and whey protein isolate (WPI) with or without guar gum addition. This kind of systems can be found in food production industry so the aim was to use novel food processing technologies to be utilized as a method for products development. Aqueous suspensions (10 g kg-1) of powdered whey proteins were treated with either ultrasound or high pressure. The treatment conditions were as follows: US: frequency of 30 kHz, for 5 and 10 min; HP: pressure intensity 300-600 MPa, for 5 and 10 min. Rheological and thermophysical properties were analyzed after guar gum addition (0.5 g kg-1). Ultrasound treatment showed a significant influence on all examined properties through protein denaturation caused by cavitation and microstreaming effects. High pressure caused significant increase in viscosity and consistency coefficients of model systems with and without guar addition. Significant decrease of initial freezing and initial thawing temperature was observed in all samples. With this research the direct influence of ultrasound and high-pressure treatment on the rheological and thermophysical properties of whey protein isolate and concentrate model systems with or without guar gum was demonstrated.Svrha ovog istraživanja je ispitati utjecaj ultrazvuka visoke snage (US) i procesiranja visokim tlakom (HP) na modelne sustave sastavljene od koncentrata proteina sirutke (WPC) i izolata proteina sirutke (WPI) sa ili bez dodatka guar gume. Ovi sustavi mogu se naći u prehrambenoj industriji, tako da je cilj ovog rada koristiti nove tehnike procesiranja kao metodu koja se može koristiti u razvoju novih proizvoda. Vodene suspenzije (10 g kg-1) proteina sirutke su tretirane s ultrazvukom ili visokim hidrostatskim tlakom. Uvjeti tretiranja su bili sljedeći: US: frekvencija od 30 kHz, kroz 5 i 10 min.; HP: intenzitet tlaka 300-600 MPa, kroz 5 and 10 min. Reološka i termofizička svojstva analizirana su nakon dodatka guar gume (0,5 g kg-1). Ultrazvučnim tretmanom pokazan je značajan utjecaj na sva ispitivana svojstva kroz denaturaciju proteina sirutke uzrokovanu putem kavitacije i učinaka mikrostrujanja. Tretman visokim hidrostatskim tlakom uzrokovao je značajno povećanje viskoznosti i koeficijenta konzistencije modelnih sustava sa ili bez dodatka guar gume. Također, zamijećeno je značajno smanjenje početne temperature smrzavanja i odmrzavanja kod svih uzoraka. S ovim istraživanjem pokazan je direktan utjecaj tretmana ultrazvukom i visokim hidrostatskim tlakom na reološka i termofizikalna svojstva modelnih sustava izolata i koncentrata proteina sirutke sa ili bez dodatka guar gume

Food Waste Originated Material as an Alternative Substrate Used for the Cultivation of Oyster Mushroom (Pleurotus ostreatus): A Review

Pleurotus ostreatus (P. ostreatus) is considered a high-quality food, rich in proteins and bioactive compounds important for maintaining human health. Lately, a commonly used substrate for oyster mushroom cultivation—wheat straw, is more often replaced by alternative cellulose substrates originated from the agricultural and food industry. Utilization of wastes for mushroom cultivation has its added value: sustainable food waste management, production of high-quality food from low quality waste, as well as solving environmental, economic and global issues. This overview covered three categories of food waste: food-processing wastes, agro-cereal wastes and nut–fruit wastes, the most used for the cultivation P. ostreatus in the period of 2017–2022. Analyzed studies mostly covered the productivity and chemical characterization of the substrate before and after the cultivation process, as well as the morphological characteristics of the fruiting bodies cultivated on a specific substrate. Chemical analyses of mushrooms cultivated on food waste are not adequately covered, which gives room for additional research, considering the influence of substrate type and chemical quality on the fruiting bodies chemical composition

Impact of Novel Nonthermal Processing on Food Quality: Sustainability, Modelling, and Negative Aspects

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Microwave extraction of bioactive compounds

Mikrovalna ekstrakcija predstavlja novu tehniku tretiranja i procesiranja prehrambenih proizvoda. U radu su prikazani primjeri mikrovalne ekstrakcije bioaktivnih spojeva. Prikazan je novi inovativni uređaj za mikrovalnu ekstrakciju i hidrodifuziju s gravitacijom. Prikazane su prednosti korištenja ovog uređaja, a to je kraće vrijeme ekstrakcije i ekstrakcija sa ili bez otapala. Nova metoda je uspoređivana sa standardnim metodama ekstrakcije. Mogu se vidjeti pozitivne i negativne strane mikrovalnog tretiranja te njihov utjecaj na razvoj oksidacije u suncokretovom ulju podvrgnutom mikrovalnom grijanju te uporaba mikrovalova kod ekstrakcije eteričnih ulja. Prikazane su i prednosti mikrovalne ekstrakcije eteričnih ulja iz aromatskog bilja bez uporabe otapala u usporedbi sa standardnom ekstrakcijom te određivanje antioksidativnih komponenata u ulju rižinih mekinja ekstrahiranih metodom mikrovalova. Opisana je usporedba mikrovalova i ultrazvuka, te pozitivne i negativne strane kombinacije mikrovalova i ultrazvuka.Microwave extraction presents novel extraction and treatment method for food processing. In paper, several examples of microwave extraction of bioactive compounds are presented. Also, novel innovative equipment for microwave extraction and hydrodiffusion with gravitation is presented. Advantage of using novel equipment for microwave extraction is shown, and it include, shorter treatment time, less usage or without any solvent use. Novel method is compared to standard extraction methods. Some positive and negative aspects of microwave heating can be observed, and also its influence on development of oxidation in sunflower oil subjected to microwave heating. Also, use of microwaves for the extraction of essential oils is shown. One can also see the advantages of solvent-free microwave extraction of essential oil from aromatic herbs in comparison with the standard extraction, and determination of antioxidant components in rice bran oil extracted by microwave-assisted method. Comparison of microwave and ultrasound extraction, as well as positive and negative aspects of the combination of microwaves and ultrasound is described