Browsing by master's degree program "Elintarviketieteiden maisteriohjelma"
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(2023)The field of food control is currently facing challenges due to phenomena such as climate change, globalization of food, and scarcity of official control resources. One important approach in improving efficient control of the safety and quality of food chains is risk-based food control. In this study, data-driven approaches were utilized to provide insights into some of the factors that have affected Finnish food business operators’ (FBOs’) compliance with food safety requirements in recent years. Qlik Sense, a data analytics solution built on the concept of visual analytics, and Python, a programming language suitable for data analysis, were used to analyze food inspection data recorded by local food safety authorities. Interactive data visualizations built in Qlik Sense aimed in supporting open government data (OGD) policies and risk-based control of the Finnish food chain, and so far, received good feedback from end-users. Additional insights into FBOs’ food safety compliance were gained by further analyzing the inspection data in Python along with municipal data. A logistic regression model fit to a subset of the study data found multiple statistically significant predictor variables from both datasets, but its performance was weak. The factors that affected food safety compliance most significantly were the number of years an FBO had operated and the basis for conducting an inspection. Operating years showed a positive correlation with compliance, while a negative relationship was observed with a variety of unplanned inspections, especially when they were conducted based on food poisoning suspects, inspection requests, or some other forms of contact. Out of all inspected food sectors, the one that increased the odds of compliance the most was the food transportation sector. The results of the study advocate for the potential of data-driven approaches in improving risk-based food control, as they are an effective way to gain insights into factors affecting the safety and quality of complex food chains.
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(2023)In instantization milk powders’ reconstitution properties are improved. Typical instantization processes are agglomeration, in which particle size and porosity are increased, and lecithination, in which powder particle surface is made less hydrophobic. Both instantization methods have some drawbacks: Agglomeration is not sufficient for instantizing high fat milk powders, while lecithination tends to decrease powder’s flowability. The aim of this study was to review suitability of agglomeration in instantizing milk powder (SMP) and whole milk powder (WMP). Powders were agglomerated on fluid bed agglomerator by using different binder liquids. The physical properties, like wettability, flowability and particle size, of the agglomerated powders were characterized and compared to the unprocessed raw materials and reference powders (commercial instantized milk powders). According to the results reconstitution properties were improved more when using other binder liquids than only water. The fastest wetting on agglomerated SMP was achieved with sugar binder liquids. However, sugar also impaired powders’ flowability. On agglomerated WMPs fastest wetting occurred with phospholipid fraction as a binder liquid. Future research could investigate usage of different binder liquids in combination and optimizing agglomeration parameters for each binder liquid.
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(2019)Ruokaturvallisuuden merkitys korostuu tulevaisuudessa muun muassa ilmastonmuutoksen, kuluttajan toiveiden ja globalisaation myötä. Ammattikeittiöissä ruokaturvallisuus painottuu elintarvikehygieniaan ja sitä toteutetaan omavalvonnalla. Omavalvonnan kirjauksia, kuten lämpötilahallintaa, on perinteisesti tehty käsin paperille ja valvonnan mittaukset ovat olleet näytemittauksia jatkuvan valvonnan sijasta. Suomalaisissa ammattikeittiöissä omavalvonta toteutuu pääasiassa hyvin, mutta lainsäädännön tulkinta, resursointi ja epäyhtenäiset toimintatavat saattavat aiheuttaa haasteita. Ihmisen rooli ruokaturvallisuudessa on merkittävä. Tänä päivänä teknologian hyödyntäminen ruokaturvallisuudessa yleistyy ja uusia innovaatioita siihen kehitetään jatkuvasti. Omavalvonta voidaan digitalisoida ja automatisoida. Tämän tutkimuksen tavoitteena oli kehittää digitaalista omavalvonnan palvelua ruokaturvallisuutta edistävästi. Tutkimus oli laadullinen tutkimus, jossa menetelminä käytettiin puolistrukturoitua teemahaastattelua ja lyhyempää kyselyhaastattelua. Teemahaastattelujen haastateltavat olivat ammattikeittiöiden keittiöpäälliköitä tai ylemmän tason esimiehiä ja kyselyhaastatteluihin vastasi keittiöiden työntekijät ja kokit. Lisäksi haastateltiin neljää valvontaviranomaista. Teemahaastattelun teemoja olivat omavalvonnan merkitys, haasteet ja ajankäyttö, digitaalisen omavalvonnan vahvuudet, heikkoudet ja kehittäminen, palveluntarjoajan rooli sekä digitaalisen omavalvonnan vaikutus ruokaturvallisuuteen. Valvontaviranomaisilla teemana oli myös valvontakäynnit. Nauhoitetut aineistot litteroitiin ja analysoitiin sisällönanalyysilla teemoitellen. Haasteita omavalvonnassa tuottivat resursointi, lainsäädännön tulkinta sekä eri tasoinen osaaminen niin ruokaturvallisuudesta kuin digitaalisista työvälineistä. Digitaalinen omavalvonta lisäsi haastateltavien mielestä ruokaturvallisuutta automaattisen lämpötilaseurannan, läpinäkyvyyden ja sitouttamisen myötä. Digitaalista omavalvontaa tulisi kehittää kahdesta näkökulmasta. Ensinnäkin, digitaalisten työvälineiden tulisi ohjata käyttäjää tekemään ruokaturvallisia ratkaisuja, perehdyttää, motivoida ja sitä kautta sitouttaa paremmin omavalvonnan tekemiseen. Toiseksi, teknologian ratkaisuja ja automatisointia tulisi lisätä laajemmin koko omavalvontaan. Eri keittiöiden eri prosessit ja sitä kautta omavalvonnan toimintamallit tulee huomioida kehityksessä.
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(2020)3-Chloro-1,2-propanediol (3-MCPD), 2-chloro-1,3-propanediol (2-MCPD) and 2,3-epoxy-1-propanol (glycidol) and their fatty acid esters are contaminants formed during processing fat containing foodstuffs at high temperatures. Mainly MCPD and glycidyl esters have been found to be formed in the deodorization process of oils, and in vegetable oils, such as palm oil, they have been measured at high concentrations. In accordance with the restrictions imposed by the European Commission, the levels of glycidyl esters must be especially monitored, as they have been identified as potentially carcinogenic compounds. The aim of the study was to introduce and validate a gas chromatographic analysis method for glycidyl esters and MCPD esters for the Customs Laboratory. The method was validated for two matrices: first for oils and then for powdered infant formulas. In addition, the success of the validation was examined by analyzing various oil samples previously received by the Customs Laboratory. The Customs Laboratory is also involved in the activities of the European Union Reference Laboratory, for which it was intended to participate in the reference measurement organized by the EU Reference Laboratory. The method for the determination of 3-MCPD, 2-MCPD and glycidyl esters in oils and infant formulas was carried out according to the guidelines of the European Union Reference Laboratory for Contaminants (EURL-PC). Determination of MCPD and glycidyl ester concentrations in oils and infant formulas included the following steps: fat extraction by liquid-liquid extraction (for infant formulas), addition of standards, solid-phase extraction, conversion of glycidyl esters to 3-MBPD esters, transesterification, neutralization, salting out, derivatization and analysis with gas chromatography-mass spectrometry system. Concentrations were determined using internal standard method. The method was validated for the following parameters: specificity, selectivity, limit of detection and quantitation, reproducibility, repeatability, trueness, linearity and working range, stability and measurement uncertainty. The analytical method developed for the determination of MCPD and glycidyl esters was successfully validated for oils and powdered infant formulas. The developed method proved to be specific and selective. The limit of determination was found to be 6.3 µg/kg, 1.3 µg/kg and 0.8 µg/kg for the oil matrix 3-MCPD, 2-MCPD and glycidyl esters. The limits of determination for the infant formula were 5.4 µg/kg, 3.0 µg/kg and 1.6 µg/kg for 3-MCPD, 2-MCPD and glycidyl esters. Recoveries for MCPD and glycidyl esters in the oil and powdered infant formulas were 83-105%. R2 for calibration lines were greater than 0.99, and the lines were linear over the entire measurement range of 2-1000 µg/kg. The relative standard deviation of repeatability and reproducibility was less than 20% for both matrices. The expanded measurement uncertainty for the MCPD and glycidyl esters of the oil and powdered infant formula was less than 50%. For all parameters, the requirements set by the Customs Laboratory and the performance requirements of Regulation (EU) 1881/2006 were met. A method validated for two matrices can then be accredited. The customs laboratory may use the developed method in the future to control 3-MCPD, 2-MCPD and glycidyl esters levels of oils and powdered infant formulas. In the future, the method could also be validated for new matrices, such as liquid infant formulas.
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(2024)In recent years, consumer interest for probiotic products has significantly grown due to their health benefits, however challenges regarding viability and controlled release of probiotic bacteria during their processing and storage still exist. Microencapsulation of probiotics by spray drying with a suitable protective material could alleviate these challenges. This research aims to assess the viability of utilizing wood hemicelluloses recovered from forest industry side-streams, specifically galactoglucomannans (GGM) and glucuronoxylans (GX), as protective agents for the probiotic strain Lacticaseibacillus rhamnosus GG (LGG) during spray drying. The study results were compared to those of maltodextrins, considering varying solid concentrations (15 and 20%) and inlet air drying temperatures (105 and 140 oC). Feed dispersion properties including viscosity, pH, particle diameter and physical stability were determined. The probiotic's viability pre- and post-spray drying was evaluated, alongside powder characterization for moisture content, water activity, particle size, morphology and structure. Results indicated that both GGM and GX effectively shield LGG from heat impact during spray drying, yielding microcapsule powders with desirable attributes such as amorphous structure and low water activity. High encapsulation efficiency (>90%) comparable to maltodextrins suggested hemicelluloses as sustainable alternatives for conventionally used wall materials. Inlet air temperature or solid concentration did not affect encapsulation efficiency of hemicelluloses. Probiotic counts met a recommended level for probiotic products, signifying potential applications in food and pharmaceuticals. Powder yield, which varied between 35 and 58%, was significantly influenced by the encapsulating material. Morphological studies demonstrated well-formed, spherical particles at a specific drying temperature. The study proposes the potential use of wood hemicelluloses for effective probiotic protection, offering new possibilities for synbiotic powder applications in diverse industries due to their prebiotic properties which have been well reported in literature. Despite promising results, long-term stability and process optimization to improve the process yield and achieve lower moisture content for the microcapsule powders require further investigation. Adjusting feed dispersion parameters and exploring varied concentrations of hemicelluloses could enhance product yield. Meanwhile, increasing outlet air temperature possibly reduces the moisture content. This research fosters sustainable development in the forest industry, presenting a novel avenue for natural functional ingredient production.
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(2023)Vacuum-packed frozen meat is popular for its longer shelf life and convenience. However, the quality and safety of these products can be compromised if the packaging material does not provide adequate protection from external factors such as oxygen, evaporation, and light. The objective of this thesis was to assess the feasibility of switching packaging materials for frozen vacuum-packed products at the case company to achieve complete recycling of packaging materials. Biochemical and sensory analysis was carried out on two different pork meats (minced shoulder and top side) packed in four commercially available packaging materials, two of which had an oxygen barrier and two had virtually no oxygen barrier. The top side samples were injected with salt and phosphate brine. All samples were stored in the freezer at -18°C for a storage period of 0-3 months. The analyses were carried out one day after both thawing and cold storage (+4°C). The top side had a storage period of two-weeks and minced meat one-week in the cold room after the thawing. Samples were analysed for TBARS, Thiols, colour, pH, and weight loss. The thiol and TBARS values, pH, a* values and weight loss were measured at different frozen storage times immediately after thawing, and after the cold storage. The results showed that frozen storage time resulted in a reduction in thiol concentrations and an increase in levels in all samples. The cold storage of samples at zero month did not influence thiol concentration, but after frozen storage samples showed a decrease in thiol concentrations. Samples packed in M1 and M2 packaging materials had less thiol content and less TBARS (P < 0.05). There were no differences in the pH of the samples packed in different packaging materials (P > 0.05). The red colour in samples packed in M1 and M2 materials were higher than in samples packed in M3 and M4 materials, but this was only in the case with minced shoulder samples and not with the top side samples. In samples packed in M1 and M3 samples the weight decreased considerably more than in samples packed in M2 and M4 samples (P < 0.05). Change in packaging material for frozen vacuum-packed frozen meat products is not advised to M3 and M4 materials. Forth considering is the choice between M1 and M2, where differed in weight loss during the frozen storage in favour of M2.
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(2023)Infants´ and children´s diet influences normal development and overall health. A balanced diet providing essential nutrients is crucial. Recent research has examined the dietary patterns of children and infants, exploring potential associations between food components and the emergence of illnesses. Notably, investigations into relationships between dietary factors and metabolite have gained prominence. Metabolomics offers a means to investigate individual´s nutrition, health status, illnesses, and the interaction of medications and contaminants. This study aimed to elucidate the connections between diet and the serum metabolic profiles of 1-year-old Finnish children. This master´s thesis used data from Finnish infants (n=439) collected by 3-day food record and questionnaires, in conjunction with metabolite assessments from blood samples collected at the age of 12 months. The investigation particularly focused on cow´s milk products and breast milk. Spearman correlation coefficient served as the primary statistical tool utilising data derived from the DIPP Nutrition study. Infant diets´ primarily comprised various cow´s milk products, milks and infant formulas. Noteworthy findings revealed that distinct lipids and free fatty acids, significantly associated with cow´s milk product consumption and breastfeeding. In the future, this study holds potential for enhancing comprehension of diet-related disease development by employing metabolites as markers to dissect dietary impacts.
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(2023)Tämän tutkielman tavoitteena oli tuottaa Propionibacterium freduenreichii -bakteerin ja Rhizopus -homesienen yhteisfermentaatiolla B12-vitamiinia härkäpavusta valmistettuun tempeen. Samalla tutkittiin, mitä aminohappoja ja orgaanisia happoja tempeissä vapautui fermentaation aikana ja vaikuttivatko ne B12-vitamiinin tuottoon. B12-vitamiinia sisältävien kasviperäisten elintarvikkeiden tuottamisen tutkiminen on tärkeää, sillä se helpottaisi vegaanista ruokavaliota noudattavien mahdollisuuksia saada B12-vitamiinia ravinnostaan. Hypoteesina oli, että B12-vitamiinia saataisiin härkäpaputempeihin, mutta oletettavasti sen pitoisuuteen valmiissa tempeissä vaikuttaisi käytetty propionibakteerikanta. Ensin kasvatettiin fermentointiin käytetyt propionibakteerikannat ja valmistettiin tempenäytteet härkäpavusta. Valmiista tempeistä määritettiin pH, kosteuspitoisuus, B12-vitamiini, vapaat aminohapot, orgaaniset hapot ja ammoniakki sekä propionibakteerien ja enterobakteerien määrät. Neljästä propionibakteerikannasta kaksi tuottivat tempeen huomattavia määriä B12-vitamiinia (1 µg/g kuivapainoa kohti). Fermentaation aikana vapaiden aminohappojen pitoisuus lisääntyi kaikilla kannoilla valmistetuissa tempeissä selvästi. Eri aminohappoja vapautui kuitenkin eri kannoilla hyvin eri määriä. Maitohappo kului näytteistä fermentoinnin aikana. Pelkällä Rhizopus -homesienellä valmistetussa näytteessä maitohapon määrä taas lisääntyi. Tämä oli tiedettävästi ensimmäinen kerta, kun tutkittiin härkäpaputempen valmistusta Rhizopus -homesienen ja propionibakteerin yhteisfermentaatiolla B12-vitamiinin tuottamiseksi. Tutkimus antoi lupaavia tuloksia B12-vitamiinipitoisen tempen valmistuksesta, sillä härkäpaputempejen vitamiinipitoisuudet olivat huomattavasti suurempia kuin mitä aikaisemmissa tutkimuksissa soija- ja lupiinitempeillä homesienen ja propionibakteerin yhteisfermentaatiossa saadut vitamiinipitoisuudet.
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(2022)Aflatoxin B1 (AFB1) is among the most potent carcinogens and mutagens known and significantly contributes to liver cancer. Mycotoxin contaminated crops, such as maize, groundnuts, or cocoa beans, are often destroyed, leading to a waste of resources. Recently, biotransformation of AFB1 by lactic acid bacteria (LAB) has been receiving growing attention. Biotransformation refers to structural change induced by enzymes or bacteria and can yield modified compounds of lower toxicity or non-toxicity compared to their precursors. Despite this growing interest, previous studies have primarily focused on the AFB1-reduction potential of LAB and biotransformation products have not been studied extensively. Therefore, this work aimed to screen twelve LAB for AFB1 biotransformation properties and analyze its degradation products. LAB were incubated in growth media for 24, 48, or 72 hours and ultra-performance liquid chromatography with fluorescence detection (UPLC-FL) was employed to measure AFB1-reduction and determine whether new fluorescent compounds appeared. Ultra-performance liquid chromatography with quadrupole time-of-flight mass spectrometry (UPLC-QTOF-MS) was used to assess the structure of the degradation products. The highest biotransformation was achieved by Lactobacillus helveticus FAM22155 (28.9 % after 72 h) and Lactobacillus helveticus FAM19191 (19.7% after 72 h). Two new peaks at 2.0 and 3.3 min retention time were observed with UPLC-FL and considered as possible degradation products. As the amount of the latter compound was very low, it could not be further analyzed. The peak at 2.0 min had a mass-to-charge ratio of 207. Two possible structures for this compound were proposed, but due to low intensities, further studies to confirm the structure are needed. This study showed that Lactobacillus helveticus can reduce almost a third of the AFB1 concentration. However, this study highlighted the challenges of identifying degradation products, and it was concluded that the extraction prior to MS should be optimized to identify degradation products. Determining the structure of the degradation products is necessary in order to evaluate whether the biotransformation results in less toxic products. In addition to evaluating the biotransformation efficacy in complex food matrices, it should be studied to determine whether biotransformation represents a promising means of reducing AFB1.
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(2022)Hexanal is a highly volatile liquid that can prolong the shelf life of fruits and vegetables (Paliyath and Subramanian 2008). Previously, Lehtonen et al. (2020) introduced a freeze-dried active packaging material which was continuously releasing hexanal through the naturally occurring lipid oxidation reactions of sunflower oil. In this study, nine different sunflower oil-based matrices were characterized at different stages of their preparation process. They contained crystallization modifiers (acylglycerols, phytosterols, or their blend), coating materials (gum Arabic and maltodextrin), and were produced by spray-drying of an emulsion. The crystallization modifiers in the matrix may enable the control over the start of the reaction for hexanal release. The emulsions with crystallization modifiers were significantly unstable, their viscosity increased with an increasing proportion of gum Arabic, and they contained crystalline regions from the first day of preparation. All tested emulsions formed a white powder after spray drying and the powder particle sizes were characterized. The differential scanning calorimetry (DSC) did not reveal any melting point of the lipid phase in majority of the powder samples. However, the DSC results showed that the melting temperatures of corresponding oleogels with acylglycerols and acylglycerol/phytosterol blend were 64 and 56.6 °C, respectively. In this thesis, emulsions containing acylglycerols and/or phytosterols were characterized and shown to be suitable for the encapsulation by the spray drying technique. Further studies focusing on the hexanal release from the matrix need to be performed since no hexanal release was detected from the powder samples.
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(2021)As the number of vegetarians and flexitarians is increasing, the demand for meat alternatives is following the same trend. Faba bean is a promising crop for environmental, health, and social reasons. From its seeds, several products can be produced, such as flour, protein concentrate, and protein isolate. These materials can be further processed for the development of texturized vegetable proteins. In this context, high moisture extrusion (HME) is an innovative technology, which requires more water, but milder temperatures than the more studied low moisture extrusion. The present thesis aimed at covering the current knowledge gap on this technology, by focusing on the flavor aspect of faba bean-based meat alternatives. The volatile profile of faba bean flour, protein concentrate, protein isolate, and mixtures was studied before and after high moisture extrusion by means of HS-SPME-GC-MS. Comparisons were made between raw materials (flour, protein concentrate, protein isolate, mixtures) and extrudates. The effect of the origin (Canadian and Finnish) of the protein concentrate was also investigated. Materials were also characterized for the following aspects: moisture, ash, protein, lipids, lipid-degrading enzymes (lipase and lipoxygenase), free amino acids, and free mono-, di-, and oligosaccharides. Several classes of volatile compounds were observed in both raw materials and extrudates, namely organic acids, alcohols, aldehydes, alkanes, alkenes, aromatic compounds, furans, esters, ketones, nitro compounds, and terpenes. Many compounds were characteristic of only one material, demonstrating that the formation of certain volatiles was product dependent. However, some other compounds were found in all materials, such as 1-hexanol, hexanal, and 2-pentylfuran. Literature addresses these compounds as responsible for the beany flavor. HME caused the inactivation of lipase and lipoxygenase but did not prevent the formation of lipid oxidation products. Products from Maillard reaction were not found in the extrudates. After HME, 1-hexanol levels decreased, whereas the abundance of 2-pentylfuran significantly increased. The behavior of hexanal after HME was less stable and predictable than the two beforementioned compounds. Not only these novel findings could have application in product development, but they also laid the basis for further research aimed at improving the flavor of faba bean.
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(2021)The objective of the research was to compare collagen characteristics, general meat quality parameters and carcass characteristics of three different muscles from freely pasturing Mangalitza Red breed and highly bred domestic/commercial pig breed. Collagen content and collagen solubility was analyzed by hydrolyzing the three different muscle samples. Meat quality parameters were analyzed previously by Natural Resources Center (Luke). The pH of Mangalitza LD muscle varied from 5.41 to 5.64, SM muscle from 5.53 to 5.75 and IS muscle from 5.74 to 5.87, IS having higher pH than the two other muscles (P < 0.05). The pH of commercial pig LD muscle varied from 5.47 to 5.75, SM muscle from 5.52 to 5.77, and IS muscle from pH 5.96 to 6.51, IS having higher pH than the two other muscles (P < 0.05). Breed had effect on pH of muscle IS (P < 0.05), but no effect on muscles LD or SM (P > 0.05). The color of muscles of Mangalitza was darker than commercial pig’s in all the three muscles (P< 0.05). In Mangalitza, LD was lighter than SM and IS, but in commercial pigs, LD and SM were lighter than IS (P < 0.05) Collagen content of all three muscles of Mangalitza differed from each other (P < 0.05) and the collagen content of LD and SM were lower (P < 0.05) than of commercial pig’s collagen content. In commercial pig, collagen content of LD and SM muscles were lower than in IS muscle (P < 0.05). Collagen solubility of all three muscles of Mangalitza differed from each other (P < 0.05) and the collagen solubility of SM and IS were lower (P < 0.05) than of commercial pig’s collagen solubility. In commercial pig, collagen solubility of LD and SM muscles were lower than in IS muscle (P < 0.05). In contrast to collagen content, collagen solubility of LD muscles did not differ between the breeds (P > 0.05). The amount and solubility of collagen did not deviate from normal; it can be concluded that this study did not provide any new information other than the collagen content and solubility of Mangalitza Red breeds muscles of LD and SM.
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(2023)Active and intelligent packaging technologies, are emerging as innovations in the food industry, aimed at enhancing food quality, safety, and sustainability. However, research indicates that, consumer awareness and acceptance, of these new technologies remains limited. This study review examined current evidence on consumer perceptions and attitudes regarding active and intelligent food packaging. Active packaging interacts directly with food products to extend shelf-life, while intelligent packaging monitors conditions and conveys information about food quality. Studies reveal that consumer awareness is moderate, with higher recognition of intelligent versus active packaging functions and technologies. Consumers generally understand potential benefits like improved food safety, quality, and freshness, but lack in-depth technical knowledge of the specific active and intelligent packaging technologies being used. Attitudes are mixed, with concerns about increased costs to consumers, uncertain environmental sustainability impacts, and potential unintended interactions between packaging ingredients and food contents. Consumers expect high standards of safety, quality, environmental sustainability, and affordability from these new technologies. However, willingness to pay a premium for active and intelligent packaging remains uncertain, highlighting the need for more consumer education and transparent communication. Further evidence-based research into the cost-effectiveness, sustainability, and safety of these technologies is critically needed to increase consumer acceptance and adoption. Additional studies should explore effective educational approaches and innovative packaging designs that address consumers' informational needs, ethical concerns, and expectations. With strategic development and commercialization, active and intelligent packaging presents a promising opportunity to enhance food systems sustainability while better serving consumer interests.
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(2022)Cronobacter spp. are opportunistic human pathogens. They can cause infections in infants and illness in older children and adults. There is also a high case fatality rate. Cronobacter spp. are found in dried foods, such as powdered infant formulas and Cronobacter spp. have caused serious cases of infection in worldwide. Therefore, Cronobacter spp. should not be present in powdered infant formulas that reach consumers. Cronobacter do not survive heat treatment. It is therefore likely that Cronobacter will migrate to the product from the environment or from heat-sensitive nutrients added after pasteurization. The data for the study was collected from the production control systems of the powder plants. Data was used for the period 2018-2020. Two powder plants, Plant A and Plant B were compared. Cronobacter results of environmental were compared with different climate variables using regression analysis, for example. Statistical analysis was performed with Minitab software. It was investigated whether the positive Cronobacter results were related to the microbiological results in the products. One subject of the review was whether seasonal variability was present in Cronobacter environmental samples. It was also examined whether explanatory factors were found for the Cronobacter results of individual targets. Based on the results of the study, there was no clear relationship between positive environmental sample results and weather conditions. Seasonal variation is also unrelated to environmental sample results. There was no statistical association between positive Cronobacter environmental results and microbiological results of the products. When examining the sampling targets, most of the positive results were found in the floor sampling targets. Based on the results, it would be a good idea to consider whether it is necessary to make changes in the hygiene areas or tighten the hygiene requirements. The use of additional shoe covers should be on option, for example. The prevention of Cronobacter in the environment is particularly important. Possible contamination of the products poses not only health risks but also financial damage. Rejection of production batches due to Cronobacter contamination can be economically significant.
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(2020)Take away food has increased in popularity in the past years. However, there are not many cardboard-based take away packaging options for restauranteurs. Plastic materials such as expanded polystyrene are most commonly used for take away packaging, but the single-use plastics directive by the European Commission has added polystyrene as one of the materials to be banned by 2021. Additionally, consumers are also becoming more educated on material sustainability, which brings added pressure and opportunity for developing new alternatives to the market. This case study implemented customer-dominant logic (CDL) to the design process of a cardboard-based take away package. In CDL, value-creation is perceived as a personal, subjective and holistic process, where the customer is in the center of the value formation process. The aim was to create a CDL based design framework and test whether it resulted in a cardboard-based take away package which created value for the consumer. The case study also aimed to uncover the factors of take away packaging which contributed to the value creation for customers. The results were collected through three consumer studies, which used qualitative methods such as responsive interviews and the Value Toolkit®. It was concluded that cardboard as a material was seen as renewable and easy-to-recycle. The cardboard-based package was successfully designed, as it was rated highest in comparison to a polystyrene-based package and a compostable bagasse package in the final consumer study. It was discovered that out of the four value types: performance, experience, status value, and responsibility, consumers thought performance was the most important in take away packaging. The CDL based framework for package design was successful. The framework can further be studied with collateral case studies, where one design team uses the CDL based framework and the other uses a more traditional approach to design.
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(2024)Lupin, a superior legume crop known for its health benefits and ability to promote crop rotation, has not been widely used for human consumption. The presence of anti-nutritional compounds (Raffinose Family Oligosaccharides (RFOs), Quinolizine Alkaloids (QAs)) and lack of essential techno-functional properties limit their application in food production. Basidiomycetes fermentation with Pleurotus ostreatus strains is one of the potential techniques capable of widening the applicability of lupins, as it degrades the antinutrients and enhances the protein profile. The effect of P. ostreatus fermentation on the flatulence causing RFOs in Lupinus angustifolius seeds was studied by fermenting dehulled and pseudo lupin seeds using liquid inoculation method. Pseudo lupin seeds, an alternative to whole lupin seeds were prepared by mixing the dehulled seeds and hulls in the same ratio as the whole lupin seeds. The saccharide profile of the control unfermented samples and fermented samples collected on the 7th,14th, and 21st days of fermentation were analyzed using High-Performance Anion Exchange Chromatography coupled with Pulsed Amperometric Detection. Intensive degradation of RFOs and simultaneous release of monosaccharides were observed in fermented pseudo lupin seeds compared to the fermented dehulled lupin seeds. The presence of lignocellulosic compounds in pseudo lupin seeds resulted in the effective growth of P. ostreatus strains and increased activity of the hydrolytic enzymes. Extending the fermentation till the development of fruiting bodies will further modify the nutritional profile of the lupin substrates, making them suitable for a wide range of food applications. In addition, oyster mushrooms with excellent sensory and nutritional properties can be cultivated.
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(2024)Some concerns have emerged about gastrointestinal symptoms from foods made from cereals and legumes due to the presence of fermentable oligo-, di-, mono-saccharides, and polyols (FODMAPs). These poorly absorbed carbohydrates ferment in the large intestine, causing rapid gas production and osmotic effects, which are particularly problematic for consumers with IBS. The challenge is to create a food product that is not only low in FODMAPs but also rich in dietary fiber and protein content to promote consumer health. This study screened various lactic acid bacteria for their ability to reduce FODMAPs, aiming to develop plant-based yogurt alternatives. The final products were then measured for different properties. A total of six yogurt alternatives were developed based on the mixture of oat bran concentrate – pea protein concentrate (OBC-PPC) and oat bran concentrate – pea protein isolate (OBC-PPI) in combination with selected Pediococcus pentosaceus and Leuconostoc mesenteroides as starter cultures. The oligosaccharide content of OBC-PPC yogurt alternatives was 0.52-0.58 g/100 g, while OBC-PPI yogurt alternatives contained 0.02-0.14 g/100 g of oligosaccharides. There was no excess fructose detected in any samples. OBC-PPC yogurt alternatives also showed a higher in vitro colonic gas production than OBC-PPI samples. Both OBC-PPC and OBC-PPI yogurt alternatives could be claimed as high in protein, with the protein content of 5.81-5.99 g/100 g. OBC-PPC yogurt alternatives could be claimed as high in fiber, while OBC-PPI yogurt alternatives could be claimed as a source of fiber. OBC-PPC yogurt alternatives showed a higher acidity than those made from OBC-PPI, while both types of products showed high water holding capacity and low syneresis. The firmness between yogurt alternatives was not significant difference, except those fermented with P. pentosaceus. This study showed the potential to develop high protein, high dietary fiber, and low-FODMAP plant-based yogurt alternatives for consumers with IBS. However, the serving size must be managed to limit FODMAP intake for those that are high in dietary fiber
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(2024)Fresh-cut lettuce and cherry tomatoes are products commonly found in ready-to-eat salad mixtures. Their individual deterioration mechanisms are well identified, whereas their interactive effects are not fully known despite their common usage in mixed salads. This hinders the identification of new targets for shelf-life improvement and the understanding of deterioration processes in post-harvest vegetables. This thesis aimed to investigate how fresh-cut lettuce and cherry tomatoes deteriorate in a mixed modified atmosphere packaging and how that impacts the shelf-life of such a product. Visual characteristics, as well as weight loss, sugars, and acid levels, were followed throughout 20 days of storage, and the changes of these prospects were evaluated, reflecting on shelf-life and taste predictions. The results presented here suggest that lettuce spoils faster than tomatoes, as indicated by higher rates of weight loss and sensorial data, thereby implying that lettuce leaves were a limiting factor in the overall quality of the mixed matrices. In addition, the rate of tomato deterioration seemed to slow down in the presence of lettuce, as at the end of the storage, the moisture and hardness losses were smaller in mixed packages. In the first week of storage, weight loss, visual data, texture analysis, and smell did not show evidence of ingredient interaction. In addition, no substantial evidence was found that the ingredients' physical contact affected the deterioration rate in mixed packages. Nevertheless, at late storage, both ingredients showed signs of deterioration, and there appeared to be effects of moisture. Also, importantly, it was found that the presence of tomatoes led to altered sugar metabolism in lettuce. However, this study encompasses only one experimental replicate, but it provides a basis for further research on ingredient interaction in mixed packages and reflects on the next possible avenues to investigate.
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(2023)Gas chromatography (GC) is one of the most widely used method for analysis of lipids and it is commonly combined to a flame ionization detection (FID), since GC-FID is an excellent combination for quantitative analysis of wide range of lipids. Before GC analysis can be performed, lipids must be extracted from the sample and derivatized. Some common extraction methods include Soxhlet and Soxtec extraction, Folch extraction and extraction with the help of acid hydrolysis. To be able to analyse the extracted fatty acids by GC, they must be in a volatile form. This can be achieved by forming fatty acid derivatives by, for example, methylation. The commissioner wishes to have a way to analyse the fatty acid composition of pork by GC in their laboratory. The aim of the study was to take in use an easy, safe-to-use and simple method for determination of fatty acid composition of pork by gas chromatography, using the instruments and equipment already found from the laboratory. The research had three different parts. First, heptane-isopropanol extraction, Bligh & Dyer extraction and Caviezel extraction were compared. Then the chosen extraction method was validated. Finally, two different pork samples were compared to test the method’s ability to differentiate them. Caviezel extraction was chosen as the best extraction method, and it was validated by parameters repeatability and robustness. The method was able to differentiate samples that had similar, but slightly different fatty acid compositions. However, method still requires some fine tuning since the GC column seemed to be highly sensitive to any disturbances.
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(2022)Aflatoxin B1 (AFB1) is a naturally occurring toxic compound produced by various types of fungi. The presence of AFB1 in food and feed can lead to severe illness, which makes it a serious threat to humans and animals. Due to global climate change, the cases of AFB1 contamination in food will increase since high temperature and humidity favour fungal growth and the production of AFB1. The bioavailability of AFB1 can be decreased by adsorption or biotransformation. Adsorption happens by the utilization of different AFB1 binding agents, which can be either mineral and organic or biological adsorbents. Mineral and organic adsorbents are only used in feed since they may also bind to nutrients. Biological adsorbents are being studied more actively since they maintain the nutritional value of the food. Studies show that Lactic acid bacteria (LAB) can be used to bind AFB1 from contaminated foods. The aim of this research was to study the capacity of different LAB (viable and nonviable) to adsorb (bind) AFB1 under different pH conditions. The research first evaluated the binding ability of AFB1 by 13 viable and nonviable LAB strains at pH 7. The best binding strains were selected for further study at pH 3 to mimic gastric pH. The AFB1 binding with cells was performed at 25℃ for 90 min. To determine the binding capacity, the solutions were centrifuged and free AFB1 in the supernatant was extracted with acetonitrile, and quick, easy, cheap, effective, rugged, and safe (QuEChERS) method was used to clean up the samples. AFB1 concentration was determined by ultra-performance liquid chromatography and fluorescence detection (UPLC-FLD). The LAB strains used in this research were shown to have the ability to bind AFB1. Binding efficacy of AFB1 depended on the bacterial strain. Viability and pH also affected the binding ability. All nonviable cells showed better binding ability (44.9–71.3%) compared to the viable cells (29.0–49.4%). The strains also had better binding capacity at lower pH regardless of the cell viability. The highest binding efficacy (71.3%) was achieved by the nonviable cell of Lactobacillus helveticus FAM 22155 at pH 3. The results of this thesis showed that some LAB strains bind AFB1 and that the binding is stable under stomach conditions. Studies to investigate the stability of the binding under simulated upper and lower gastrointestinal (GI) tract conditions (in vitro digestion) and in vivo studies are needed in order to provide further evidence of the applicability of LAB in lowering the bioavailability of AFB1.
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