Níveis crescentes de zeolita (clinoptilolita) - 0%; 1,5%; 3,0%; 4,5% - foram utilizados com o intuito de se avaliar a qualidade e a palatabilidade de biscoitos para cães. No âmbito da qualidade de produto foi avaliada a atividade de água, através da mensuração da umidade relativa de equilíbrio, a coloração, utilizando-se colorímetro em sistema CIEL*a*b, a textura através de texturômetro com sonda específica e a ordenação de preferência por parte dos proprietários de cães. O ensaio de palatabilidade foi realizado com 14 cães adultos, sem raça definida, machos e fêmeas, com idade média de seis anos e peso médio de 14kg. Foi utilizado delineamento inteiramente casualizado. Nos níveis de inclusão de 3% e 4,5% a zeolita diminuiu (p<0,01) os valores de atividade de água e para todos os níveis testados não houve efeito (p<0,01) na coloração de biscoitos para cães. A pressão de cisalhamento foi crescente (p<0,01) nos tratamentos 0%; 1,5% e 3,0%, respectivamente. Porém, sofreu uma queda (p<0,01) no nível de inclusão de 4,5%. Na análise sensorial os proprietários de cães preferiram (p<0,05) para o parâmetro cor o nível de 0% de inclusão de zeolita, para o odor os níveis 0% e 1,5% e para a dureza os níveis 0% e 4,5%. No ensaio de palatabilidade, tanto para primeira escolha, como para a razão de ingestão, houve diferença (p<0,01) significativa, sendo o nível de 3% de Zeolita o preferido, seguido dos níveis 4,5%, 0% e 1,5%, respectivamente. Mesmo não havendo efeito na coloração, a adição de Zeolita (clinoptilolita) altera a qualidade de biscoitos para cães, causando uma diminuição na atividade de água, nos níveis de 3,0% e 4,5% de inclusão e modificando a textura nos níveis 1,5% e 3,0%. Diferentes níveis de zeolita na composição de petiscos podem ser identificados pelos cães / Increasing levels of zeolite (clinoptilolite) - 0%, 1.5%, 3.0%, 4.5% - were used in order to evaluate the quality and palatability of dog biscuits. Concerning product quality water activity was evaluated by measuring the equilibrium relative humidity, coloring by colorimeter on the CIEL *a*b system, texture through texturometer using three point bending rig probe and ordering of preference for the dog\'s owners. The palatability test was conducted with 14 adult dogs, mixed breed, male and female, with an average age of six years, and an average weight of 14kg. The statistical design was applied in a completely randomized study. In inclusion levels of 3.0% and 4.5% of zeolite decreased (p <0.01) the values of water activity and at all levels tested did not affect (p <0.01) in staining. The shear stress is increased (p <0.01) between treatments 0%, 1.5% and 3.0%, respectively. However, has declined (p <0.01) on level of inclusion of 4.5%. In the sensory analysis dog owners preferred (p <0.05) for the color parameter 0% of inclusion, for the odor 0% and 1.5% and hardness 0% and 4.5%. In palatability test, both first choice and ratio of ingestion had significant differences (p <0.01) between the levels tested and the level of 3% zeolite was preferred, followed by 4.5%, 0 % and 1.5% levels, respectively. Even without effecting coloring, adding zeolite (clinoptilolite) alters the quality of dog biscuits, causing a decrease in water activity on levels of 3.0%, and 4.5% inclusion and changing the texture on levels 1.5% and 3.0%. Different levels of zeolite in the composition of snacks can be identified by dogs

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This master’s thesis deals with the general characteristics of drying processes, types of moisture and bonds in the material. The following describes the drying process and selected drying equipment. It also includes a chapter on proteins, their changes in the air with increasing temperature. This thesis also describes denaturation of proteins as well as activity of water and it‘s dependence on microbial reactions in food. The practical part is focused on experimental measurement of the drying curves of crushed larvae, their construction and subsequent evaluation. The last part is devoted to measuring the activity of water samples of crushed larvae of different moisture.

The project was carried out in collaboration with Lantmännen with the aim to analyse the lipase activity in oat endosperm, non-heat-treated whole grain oat flour and heat-treated whole grain oat flour and to investigate whether lipase activity could be inactivated in oat endosperm by reducing water activity by various methods such as oven drying and freeze drying to extend oat shelf life. Lipase activity was measured by a wet extraction of the flour and an artificial substrate that gives a coloured product if lipase enzymes are active in the extract. The formation of the product was measured during five minutes at room temperature or 37 °C using a spectrophotometer, and the enzyme activity in units/g of flour was calculated. It was not possible to measure the enzyme activity in the flour directly. The obtained results for the different oat fractions indicated differences in lipase activity between the oat fractions. Lipase activity for oat endosperm was 0.183 U/g, lipase activity for non-heat-treated whole grain oat flour was 0.088 U/mg and the heat-treated whole grain oat flour had no lipase activity. The differences were statistically significant since the p-value was <0.0001. The results from the analysis that compared whether oven-drying and freeze-drying as methods had an effect on lipase activity indicated that oven drying had the greatest effect when assay was performed at room temperature. However, when the assay was performed at 37 °C the lipase activity in oven-dried and freeze-dried oat endosperm were similar to non- treated samples. This indicates that temperature has a great impact on the lipase activity. Thus, oven drying and freeze drying could not completely inactivate the lipase activity, but probably reduce it.

The decrease in subtherapeutic antibiotic administration in poultry has increased the need to address production challenges caused by pathogens, such as E. coli. One potential way to improve bird health and reduce bacterial infection is through the addition of litter amendments that absorb moisture. Biochar (BC) has previously been shown to increase water holding capacity in poultry litter, but its effects on E. coli mitigation are unknown. The objectives of this research were to 1) evaluate water activity of poultry litter amended with pine and miscanthus BC, and 2) determine the effects of different BC inclusion rates on litter E. coli populations. The studies found that BC increased water activity when mixed with broiler litter, and pine BC resulted in lower E. coli counts over time than miscanthus BC. An inclusion rate of 30% by weight of pine BC was most effective at reducing E. coli populations in broiler litter.

The importance of reducing people's environmental impact has become increasingly apparent since the beginning of the 21st century. According to the European Parliament, new legislation has been required to stop the deterioration of Europe's waters and to achieve "good status" for Europe's rivers, lakes and groundwater. This legislation was introduced in year 2000 under the name of The EU Water Framework Directive. The EU Water Framework Directive was first implemented in Sweden in 2004 and has since continued to be implemented through several laws. In January 2019, in Swedish law, there were requirements for modern environmental conditions on water activity, as for the production of hydroelectric power or when the business was started was intended for such production. Sweden's government has in 2018 produced a proposal for a national plan that aims to facilitate the trials of water activities in order to reach the requirements for modern environmental conditions. The problematisation of this is how the implementation of the new requirement for modern environmental conditions should take place and to see what applies if conflicts of interest arise. The essence of the essay is to lead a deeper understanding and discussion of how the requirements for modern environmental conditions can affect interested parties around Sweden. The essay is based on a knowledge base that consists of the legislation in the subject, significant legal cases and a qualitative method through various semi-structured interviews. Limitations for the essay are that it only depicts the implementation of the European Parliament's directive in the Swedish Law and interested parties who are only active in Sweden. Finally, the study shows that many problems are assumed to occur when the trials in connection with the modern environmental conditions begin. Most prominent is the application of the EU Water Directive, costs and environmental impact. / Vikten av att minska människors miljöpåverkan har sedan början av 2000-talet blivit allt mer påtaglig. Enligt Europaparlamentet har det krävts en ny lagstiftning för att stoppa försämringen av Europas vatten och att nå "god status" för Europas floder, sjöar och grundvatten. Denna lagstiftningen infördes år 2000 vid namnet EU:s ramdirektiv för vatten. Direktivet implementerades först i Sverige år 2004 och har sedan dess fortsatt att implementeras via ett flertal lagar. I januari 2019 tillkom i svensk lagstiftning krav om moderna miljövillkor på vattenverksamheter för produktion av vattenkraftsel eller när verksamheten påbörjades var avsedd för sådan produktion. Sveriges regering har under 2018 tagit fram ett förslag till en nationell plan som har till syfte att underlätta prövningarna av vattenverksamheter för att nå kraven om moderna miljövillkor. Problematiseringen av detta är hur implementeringen av det nya kravet om moderna miljövillkor ska ske och att ta reda på vad som gäller om intressekonflikter uppstår. Uppsatsen huvudsakliga syfte är att leda en djupare förståelse och diskussion om hur kraven om moderna miljövillkor kan påverka berörda parter runt om i Sverige. Uppsatsen bygger på en kunskapsgrund som består av lagstiftningen inom ämnet, väsentliga rättsfall och en kvalitativ metod genom olika semistrukturerade intervjuer. Avgränsningar för uppsatsen är att det endast skildrar implementering av Europaparlamentets direktiv i svensk lag samt berörda parter som endast är verksamma i Sverige. Slutligen visar studien att många problem antas uppstå när prövningarna i samband med de moderna miljövillkoren påbörjas. Mest framträdande problem är tillämpningen av EU:s ramdirektiv för vatten, kostnader och miljöpåverkan.

Poultry litter amendments (LA) are commonly used to maintain good litter quality; the most common ones; are acidifiers. However, concern over the lifespan of LA acidifiers (d) and corrosive nature revealed a need for alternative LA. Products of interest include biochar (BC), superabsorbent polymers (SAPs), and alum mud (AM). Experiment 1 was a screening study (n=17 treatments, no birds) conducted to determine the optimal application rate/method of BC, SAPs, and AM vs.commercial LA and a control. Most SAPs treatments measured metrics may be similar (i.e., bacteria, water activity) or better (pH) vs. commercial LA (PLT). High inclusions of novel LA elicited the most litter quality benefit; therefore, were chosen for experiment 2 to determine their effects on 60 d litter quality and broiler performance and processing. Overall, novel LA improved litter quality parameters (i.e., moisture content, pH water activity) without negatively affecting live performance and processing parameters vs. control

Coffee grown in the United States represents less than 1% of the world's supply, and most of it comes from the state of Hawai'i. Kona coffee, grown on the western side of the island of Hawai'i, is the most recognized and the highest value Hawaiian coffee. The majority of this coffee is sun-dried after harvest and washing. Sun-dried coffee should reach 12-13% moisture within 4 to 6 days. Sun-drying will reduce both the moisture content and the water activity (aw). Reducing aw below 0.75, especially in the first week of drying, is important for preventing or limiting mold growth. The purpose of this study was to 1) compare drying rates of Kona coffee bean batches using aw and moisture content % measurements, 2) evaluate factors affecting the drying time of sun-dried Kona coffee, and 3) provide recommendations for post-harvest processing of sun-dried Kona coffee to optimize quality and safety. Ten farms in the Kona coffee region of Hawai'i were visited in the fall of 2017 to record data on the drying rate of coffee bean batches and to record observations on the post-harvest handling and storage of coffee beans and the environmental conditions that may affect the quality and microbial contamination of drying coffee. The coffee drying surfaces, physical enclosures, fan use, and elevation varied among farms. Daily measurements of coffee moisture level, water activity, depth of bean layer and temperature were recorded along with air temperature, relative humidity and cloud cover during drying for 30 batches. Most sun-dried batches reached 13% moisture in 6 to 10 days. Initial moisture content (31.6 4.3%), and drying yard characteristics varied greatly among farms. Coffee batches reached 0.75 aw within 6 days on average, but some batches required more than 10 days. Moisture content and aw measurements were weakly correlated and water activity level increased at times during drying for some batches. Allowing airflow around drying beans and maintaining a bean layer depth of less than 5 cm appeared to improve drying rates. Drying coffee parchments within 7 days post-harvest can inhibit growth of molds that may impact quality or molds that could produce mycotoxin. Controlling the drying conditions, including raking the layered beans, and monitoring moisture content can accelerate, or improve the consistency of, batch drying time. / Doctor of Philosophy / Coffee grown in the United States represents less than 1% of the world’s supply, and most of it comes from the state of Hawai’i. Kona coffee, grown on the western side of the island of Hawai’i, is the most recognized and the highest value Hawaiian coffee. The majority of this coffee is sun-dried after harvest and washing. Sun-dried coffee should reach 12-13% moisture within 4 to 6 days. Sun-drying will reduce both the moisture content and the water activity (aw*). (*Water activity is the measurement of water vapor pressure generated by the free or non-chemically bound water in foods and other products. Water activity (range of 0 to 1) is an important indicator for the shelf life of foods and the occurrence and growth of microorganisms). Reducing aw below 0.75, especially in the first week of drying, is important for preventing or limiting mold growth. The purpose of this study was to 1) compare drying rates of Kona coffee bean batches using aw and moisture content % measurements, 2) evaluate factors affecting the drying time of sun-dried Kona coffee, and 3) provide recommendations for post-harvest processing of sun-dried Kona coffee to optimize quality and safety. Ten farms in the Kona coffee region of Hawai’i were visited in the fall of 2017 to record data on the drying rate of coffee bean batches and to record observations on the post-harvest handling and storage of coffee beans and the environmental conditions that may affect the quality and microbial contamination of drying coffee. The coffee drying surfaces, physical enclosures, fan use, and elevation varied among farms. Daily measurements of coffee moisture level, water activity, depth of bean layer and temperature were recorded along with air temperature, relative humidity and cloud cover during drying for 30 batches. Most sun-dried batches reached 13% moisture in 6 to 10 days. Initial moisture content (27 to 36 %), and drying yard characteristics varied greatly among farms. Coffee batches reached 0.75 aw within 6 days on average, but some batches required more than 10 days. Moisture content and aw measurements were weakly correlated and water activity level increased at times during drying for some batches. Allowing airflow around drying beans and maintaining a bean layer depth of less than 5 cm appeared to improve drying rates. Drying coffee parchments within 7 days post-harvest can inhibit growth of molds that may impact quality or molds that could produce mycotoxin. Controlling the drying conditions, including raking the layered beans, and monitoring moisture content can accelerate, or improve the consistency of, batch drying time.

The pathogenic microorganism Salmonella enterica has been associated with several outbreaks and recalls of spices, herbs, and seeds. To control these pathogens additional treatment methods, such as fumigation with chlorine dioxide (ClO2) or hydrogen peroxide (H2O2) gas and recovery methods are needed. Recovery methods should accurately quantify all viable cells, even those injured, to prevent overestimation of treatment effectiveness. This study was performed to determine the effect of different recovery media and supplements on the recovery of multiple strains of S. enterica and Enterococcus faecium NRRL B2354, from chlorine dioxide or hydrogen peroxide treated low moisture foods (LMF) black peppercorns, dried basil leaves, and chia seeds. Also, this study aimed to compare the log reduction of these two microorganisms to evaluate E. faecium NRRL B2354 as a surrogate for S. enterica. On average, recovery of S. enterica was 3.43 log and 4.77 log CFU/g from ClO2 and H2O2 treated LMFs, respectively on the selective media Xylose Lysine Deoxycholate agar, while the average recovery on non-selective media was 4.50 log CFU/g and 5.74 log CFU/g from ClO2 and H2O2 treated LMFs, respectively. The use of non-selective media was correlated with increased recovery compared to selective media. In further studies, addition of sodium pyruvate, ferrous sulfate, or 3'3'-thiodiproionate supplements to MTSAYE did not show increased recovery (P>0.05). On each treatment and LMF combination tested, there was no significant difference between the log reduction of S. enterica and E. faecium NRRL B2354, indicating its suitability as a surrogate under the test conditions. / Master of Science in Life Sciences / Spices, dried herbs, and seeds have become popular throughout the world for enhancing the flavor of food, but may also harbor harmful bacteria, including Salmonella enterica. It is US federal law under the Food Safety Modernization Act that these foods are safe to eat straight from processors since these foods are typically consumed raw. Novel treatment methods are being tested to kill harmful bacteria on these dried foods without adding water including chlorine dioxide fumigation and hydrogen peroxide fumigation. However, these processes can injure the bacteria without killing them. These injured bacteria might not be counted using traditional means which could lead to overestimating the effectiveness of a treatment. Different media types, used as part of the process to count the number of bacteria in a sample, were tested to determine their effect on recovery of injured S. enterica cells. Furthermore, the bacterium Enterococcus faecium NRRL B2354 was tested against S. enterica to evaluate, if the former, a relatively harmless microorganism, could be used by food processing plants to determine that their treatment processes meets regulatory standards. More injured S. enterica cells were recovered from each non-selective media tested, compared to the selective media. Although there isn't a significant difference in injured S. enterica recovery between any supplemented non-selective media, any non-selective media recovers more sub-lethally injured cells, and would give more accurate bacterial counts. Results also indicated that E. faecium NRRL B2354 is a suitable surrogate to the pathogen S. enterica for spices and herbs processed under the same conditions.

Saturated steam (SS) and propylene oxide (PPO) fumigation are two common methods to improve microbiological quality and safety of tree nuts. Validation of these processes is needed to ensure adequate control of bacterial pathogens. Since pathogens cannot be studied in food processing environments, surrogates with resistance comparable to the pathogens needed to be identified. The objective was to investigate the suitability of Enterococcus faecium, Pediococcus acidilactici, and Staphylococcus carnosus as surrogate bacteria for Salmonella spp. on whole cashews and macadamia nuts, processed with SS or PPO. Whole cashews and macadamia nuts were co-inoculated with a cocktail of Salmonella enterica and one of the three potential surrogates. Nuts were dried to original aw, packaged in poly-woven bags (2.3 kg) and commercially processed using vacuum assisted steam at 80 ͦ C or PPO fumigation. Salmonella and the potential surrogates were enumerated by serial dilution, and plated onto TSA with overlay of XLT-4 (Salmonella) or media selective for the potential surrogates. Mean log reductions (CFU/g) of Salmonella and each potential surrogate were compared using a paired T-test. SS results: reduction of Salmonella (6.0 ± 0.14) was significantly larger than E. faecium (4.3± 0.12), or P. acidilactici (3.7± 0.14) on whole cashews. Salmonella (5.9 ± 0.18) was significantly larger than P. acidilactici (4.4± 0.18) on whole macadamia nuts. PPO results: reduction of Salmonella (7.3 ± 0.19) was significantly greater than E. faecium (6.4± 0.31), or P. acidilactici (6.3± 0.33) on whole macadamia nuts. Reduction of Salmonella was significantly greater than E. faecium and P. acidilactici reduction on cashews. P. acidilactici may be considered a surrogate for Salmonella reduction on whole macadamia nuts and whole cashews processed using SS at 80 ͦ C. E. faecium and P. acidilactici may be considered surrogates for Salmonella reduction on whole macadamia nuts and whole cashews processed using PPO. Reduction of St. carnosus exceeded that of Salmonella indicating it is not a suitable surrogate for Salmonella using either processing intervention. / Master of Science in Life Sciences / Tree nuts are produced and consumed worldwide, playing a role as a snack or ingredient in foods in several cultures. Traditionally, tree nuts have been believed to be microbiologically safe due to their composition and lack of water available to harbor pathogenic bacterial growth. However, recent years have proven to be problematic for many tree nuts and nut products, numerous recalls have occurred in the United States for verified contamination of <i>Salmonella</i>. Since <i>Salmonella</i> can be found in food systems worldwide, and is a leading cause of foodborne illness due to bacterial contamination of food, steps must be taken to improve the safety of nuts grown locally and imported products. With several processing options for tree nuts, two that are commonly practiced to reduce microorganisms include a fumigation of product using propylene oxide (PPO) and a thermal inactivation treatment through use of saturated steam. The comparison of <i>Salmonella</i> inactivation and non-pathogenic surrogate bacteria on cashews and macadamia nuts, being processed in these two manners, was investigated. Possible bacteria strains that were investigated for surrogacy were <i>Enterococcus faecium</i> NRRL B2354 (ATCC #8459), <i>Pediococcus acidilactici</i> (ATCC #8042), and <i>Staphylococcus carnosus</i> (ATCC #51365). Surrogates are bacteria that have similar inactivation characteristics to <i>Salmonella</i> when processed, that can be purposely introduced before processing to ensure inactivation of <i>Salmonella</i> and is harmless if consumption occurs. Studies continue to ensure safety of tree nuts as well as complying with pending and future regulations.