A computational fluid dynamics model was designed to study the problem of thermal processing of a liquid food product containing whey proteins within a heat exchanger consisting of heating, holding and cooling tubular sections. This physical problem is associated with strong coupling between the phenomena of fluid flow, heat transfer, and thermal denaturation-aggregation of whey proteins. Our primary objective was to investigate the two-way coupling between these phenomena within the heat exchanger. This was carried out by analyzing the model predictions of velocity, temperature and product properties at both axial and radial directions. Attention was focussed on the whey proteins present in a cream cheese formulation. The thermal denaturation-aggregation kinetics was supposed to follow that of the beta-lacto-globulin, which plays a major role in fouling when milk derivatives are submitted to thermal processing in heat exchangers. Model predictions demonstrated that the apparent viscosity of the liquid product exhibited a complex behavior along the processing unit: in addition to its dependence on local temperature, it was affected by the local degree of denaturation of whey proteins – and hence on the product history previous to this position in the heat exchanger. The numerical model was structured into a sequence of computational domains; its versatility was illustrated by changing the length of the holding section and then assessing the impact on the final degree of denaturation of the whey proteins present in the liquid product.

This study evaluated the effectiveness of black rice, millet and barley bran extracts against oxidative degradation of sunflower oil in frying, by determining the total antioxidant activity, total phenolic content, free fatty acid content, conjugated diene content and total polar content. It was reported that the total phenolic content rice bran was approximately three times higher than that of the millet bran extracts and five times higher than the results for barley bran extracts. The total antioxidant activity results for barley bran and rice bran extract (40.95 ± 0.07and 40.87 ± 0.04 Trolox equivalent μmol/g of bran, respectively) were two times higher than that of millet bran extract (17.16 ± 0.34 Trolox equivalent μmol/g of bran). The results of the effectiveness of the cereal bran extracts were significantly different (p<0.05). The free fatty acid content of the rice bran and propyl gallate enriched oil samples showed better results (2.02 ± 0.01% and 1.62 ± 0.00%) than millet, barley and control enriched oil samples (3.43 ±0.01%, 3.13±0.01% and 6.13 ± 0.01% respectively). In the same vein, conjugated diene content results from all the enriched oil samples indicated that the rice bran enriched oil sample had the least amount of secondary oxidized products compared to the other enriched oil samples. It can be concluded that rice bran extract can be used for frying without discarding or replenishing the oil.

Different parameters in cider processing were evaluated using different cultivars of Norwegian-grown table apples measuring the quality of cider. Seven different apple cultivars were mixed into four different apple juice mixtures. In this experiment, we evaluated the maturation of the apples along with commercial cider yeast and spontaneous alcoholic fermentation. Other parameters were fermentation temperature and filtration along with content of polyphenols, organic acids and volatile compounds that was analysed as an effect of the fermentation process. Succinic acid was the major organic acid in apples and ciders. The different apple juice mixtures did not reveal pyruvic and acetic acids but they appeared in relatively high amount in the ciders. The level of citric acid increased from apple to cider. Chlorogenic acid was the major polyphenolic compound found from 13-109 mg L-1 in the apple juice mixtures and between 27-200 mg L-1 in the ciders. The higher alcohol 3-methyl-1-butanol appeared in relatively large amounts in all the ciders (91-166 mg L-1). The average content of acetaldehyde increased during the fermentation process, from apple juice mixtures 2.75 mg L-1 and 14.65 mg L-1 in the ciders. The content also increased for ethyl acetate with levels at 0.1 mg L-1 in the apple juice mixture and 20 mg L-1 in the cider. In the sensory evaluation experiment, the ciders produced from the apple cultivars Aroma, Gravenstein and Summerred got higher scores in fruitiness and complexity compared to the other apple juice mixtures.

The aim of this work was to study the influence of the ripening degree of natural goat cheese on texture, rheological and sensory properties of processed cheese products. Processed cheeses were formulated using goat cheeses with 10, 20, and 40 days of ripening. We obtained four different formulations by varying the proportions of these cheeses in each formulation. The variation in major α, β, and para-κ casein fractions, rheological properties, and the texture of samples were determined, and a sensorial evaluation was carried out. Cheeses from Formulation 2 (50% cheese ripened for 10 days, 25% cheese ripened for 20 days and 25% cheese ripened for 40 days) had greater values of α and β –caseins, which is related to a greater content of intact casein resulting from a cheese with short ripening time. Hardness, adhesiveness and complex modulus (G*) decreased as the degree of ripening of the natural cheese (raw material) increased. Formulation 2 presented a G* value similar to that of the commercial processed cow cheese and the greatest firmness. Formulation 2 presented the characteristics we aimed to obtain, described as spreadable, slightly acid and salty cheese.

Eggs and their products such as desserts, confectioneries, bakery mixes, mayonnaise and many convenience foods have been implicated in food-borne disease outbreaks due to microorganism contamination. The effect of gamma irradiation on the presence of microorganisms in egg powder was investigated. Egg powder samples were exposed to several doses of irradiation: 0, 5, 10 and 15 kGy and stored for up to 12 months at ambient temperature (25 oC). Results indicated that the total viable count (TVC) (5.56 log10 cfu g-1), total coliform counts (TCC) (6.46 log10 cfu g-1) and mold and yeast counts (MYC) (9.12 log10 cfu g) in un-irradiated (control) samples of egg powder were higher than the maximum limits (4.88, 2.00 and 1.70 log10 cfu g-1, respectively). Application of the higher doses (10 and 15 kGy) decreased the TVC, TCC and MYC of the egg powder samples to less than 1 log10 cfu g-1 and the counts remained almost constant during storage for 12 months. D10 values for Escherichia coli and Salmonella typhimurium were 0.714 and 0.278 kGy, respectively. Gamma irradiation treatment could be chosen on the basis of preliminary microbiological tests including TVC, TCC and MYC and help improve the hygienic quality by killing and reducing the microorganisms that might be present inside of egg powder to meet national and international standards.

Food is a necessity of human beings, and the consumption of food is aimed at obtaining energy and nutrients necessary for the growth and proper functioning of the body. However, food can also be a vehicle for various diseases, and the causal agents can have physical, chemical or biological origin with relevance to health due to their incidence, mortality and negative consequences in the population. Bacteria are the main agents of biological origin associated with foodborne diseases. Among these microorganisms are species of the genus Campylobacter, which cause a zoonosis with one of the highest incidences globally, known as Campylobacteriosis. This document provides an overview of foodborne diseases, specifically the causal agents of Campylobacteriosis, including the different measures of control and prevention for this disease in different foods such as poultry, milk, meat, and fish, among others. It also covers the phenomenon of resistance to antimicrobials by these pathogens and the health implications to consumers. The above can generate and maintain safety practices in food production for the protection of public health in different regions around the world.

Barhi Dates are an important food and often consumed and sold in the market during the stage Khalal, when the colour is yellow and their taste is sweet with the disappearance of their astringent taste. During the Khalal stage, these dates become physiologically mature with gives the sweet taste. For this reason, they are sold and consumed in a short period of time before these fruits turn into Rutab, a stage at which they lose that distinguishing characteristic. The high moisture, rapid ripening, and delays in transportation or improper storage conditions quickly result in Rutab stage. Thus The Khalal stage lasts for a short time until the fruits get ripe. In the present study, Barhi Khalals were packaged in air (control) and by two types of modified atmosphere packaging: MAP A (5% O2+ 20% CO2 and 75% N2) and MAP B (40% O2+ 20% CO2 and 40% N2). Afterwards, all samples were stored at 5°C for 30 days. On days zero, 10, 20 and 30 of storage, the fruits were evaluated in terms of the changes in the quality indices of weight loss, colour, Total Soluble Solids (TSS), and firmness of the fruits and sensory features. The results showed that the minimum weight loss was 0.45% in modified atmosphere packaging, especially with MAP A and the minimum increase in the TSS was 37.35 Brix° after 30 days of the storage. On the other hand, the results for firmness, colour, and sensory evaluation were better with control packaging.

Many innovative teaching and learning methods are used in higher level education including project-based learning (PBL). Since 2012 a PBL assignment project has been undertaken by master students of the Advanced Molecular Gastronomy module at Technological University Dublin (TU Dublin). The aim is to stimulate student learning and creativity by using Note by Note cooking in a PBL assignment while at the same time complying with the requirements of the annual International Note by Note contest which is held in Paris, France. Direct and indirect assessment methods were used to assign individual grades and to gather student feedback about the module. The direct methods were both formative and summative. The indirect method used was a student feedback questionnaire. Results to date (2012-2019) showed that 92% of learners successfully passed the module. However, further evaluation of individual assessment results revealed that most students achieved higher scores for finding and using resources, asking further questions and developing their own answers than for analysing, synthesising and evaluating information (P≤0.01). Overall students were happy with the module content and said that they learnt about Note by Note cooking, chemical compounds, researching, independent-thinking and perseverance. In future students should carry out a more in-depth analysis, synthesis and evaluation of information.

This research aims to examine the effects of fermentation time on the physicochemical and sensory characteristics of green coconut water kefir in order to determine the optimal fermentation time based on the resulting sensory attributes. There were four fermentation time treatments (12, 24, 36, and 48 hours), each with five replications. The materials used were green coconut water and 5% kefir grains. Physical analyses included pH and viscosity, while the chemical analyses included total dissolved solids (TDS), alcohol content, water content, protein content and fat content. Sensory attributes included sourness, soda sensation, sour aroma, viscosity and turbidity. The results showed that fermentation time had significant effects on pH, TDS, alcohol content, water content, protein content and the sensory attributes of green coconut water kefir. Viscosity and fat content were not affected by fermentation time. The ideal fermentation time was 12 hours resulting in a pH level of 4.6, viscosity of 0.09, TDS of 3.8° Brix, alcohol content of 1.16%, water content of 97.14 %, protein content of 6.64 % and fat content of 1.17%. Sensory evaluation found a low level of sourness, low soda sensation, high sour aroma, high viscosity and low turbidity.

Currently, improvement of food preservation has been a substantial challenge for industries to increase shelf-life of products and to maintain food quality during storage. These goals are often tied to the sustainable tendency for use of eco-friendly packaging to store these products without loss of the packaging features. Therefore, the aim of this study was to produce biodegradable antimicrobial films by the incorporation of nisin Z peptide under different concentrations (0 %, 5 %, 10 %, 15 % and 20 % wt.) into hydroxypropylmethylcellulose (HPMC) matrices. The active film properties were evaluated in terms of their antimicrobial capacity in vitro, mechanical performance and microscopic characteristics. Hence, active films containing 10 % (wt.) of nisin Z and control films were placed in contact with sliced mozzarella cheese for eight days, and microbiological growth was monitored during storage. Nisin Z’s antimicrobial effects were observed against the Gram-positive microorganisms such as Staphylococcus aureus and Listeria innocua, regardless if the compound was free as a suspension or incorporated into HPMC matrices. However, the expected low action of nisin Z against Gram-negative bacteria, as reported in literature, was not observed since Salmonella enterica Choleraesuis’s growth was inhibited. Moreover, active films with added nisin Z (10 % wt.) were more effective than the control film to inhibit mesophilic microorganisms in mozzarella cheese during 8 days of storage. The mechanical properties of the films were not influenced by nisin Z incorporation, since the addition of the compound enhanced the active function without the loss of mechanical properties required for a good food packaging. These results suggest that biodegradable films produced by nisin Z addition into HPMC matrix are an excellent biomaterial for mozzarella cheese preservation.