Current Perceptions of Sustainable Diets in Ireland and the Outlook of Circular Eating Practices.

Encouraging sustainable dietary practices is a positive step towards alleviating the negative impact of increasing food waste. This study explores consumers' perceptions of sustainable diets and factors influencing their adoption of sustainable practices, such as circular eating. Fifteen consumers in Ireland aged 18-65+ years were recruited for a qualitative study exploring their views on sustainable diets and their opinions on the use of peels, trimmings, and other by-products from fruit and vegetables as potential new ingredients or new circular food products. Age, gender, dietary preferences and educational background were important considerations during recruitment. Online interviews were conducted, and the data were analyzed using thematic analysis managed by NVivo 12. The results highlighted two overarching themes impacting circular eating, namely, food choice motives and awareness of food waste. These were linked to the participants' knowledge of and potential adoption of sustainable diets. Daily trade-offs were evident, linked to the product and the person who was also strongly influenced by their micro-environment. Consumer education from credible sources would be required to create awareness of circular eating. Most respondents were positively disposed to the concept of circular eating, as long as food safety concerns and affordability considerations were addressed through industry transparency.

Impact of Enzymatic Hydrolysis and Heat Inactivation on the Physicochemical Properties of Milk Protein Hydrolysates.

This study determined the physicochemical properties (apparent viscosity (ηapp), turbidity (A550nm), particle size and molecular mass distribution) of hydrolysates generated from whey protein concentrate (WPC), milk protein concentrate (MPC) and sodium caseinate (NaCN), following incubation with Debitrase HYW20™ and Prolyve™ at 50 °C, pH 7.0 for 1 and 4 h, before and after heat inactivation (80 °C for 10 min). The degree of hydrolysis (DH) increased with incubation time, giving values of 6.56%, 8.17% and 9.48%, following 1 h hydrolysis of WPC, MPC and NaCN with Debitrase HYW20™, and 12.04%, 15.74% and 17.78%, respectively, following 4 h incubation. These DHs were significantly higher compared to those obtained following 4 h incubation with Prolyve™. Hydrolysis with Debitrase HYW20™ gave >40% of peptides with molecular masses < 1 kDa for all substrates, which was higher than the value obtained following hydrolysis with Prolyve™. The effect of hydrolysis on the physicochemical properties was substrate dependent, since ηapp decreased in WPC and NaCN hydrolysates, particle size decreased for all the substrates, with aggregate formation for MPC, and turbidity decreased in WPC and MPC hydrolysates, while it increased in NaCN hydrolysates. The physical properties of the hydrolysates were influenced by the enzyme thermal inactivation step in a DH-dependent manner, with no significant effect on turbidity and viscosity for hydrolysates at higher DHs.

The effects of cooking salmon sous-vide on its antithrombotic properties, lipid profile and sensory characteristics.

Fish contains bioactive polar lipids (PL) and is mainly consumed cooked. The aim of this study was to evaluate the sensory characteristics of sous-vide cooked salmon and the in vitro cardio-protective properties of its PL. PL were extracted from brined and un-brined sous-vide preparations in 52 °C, 65 °C, and 80 °C, while their antithrombotic cardio-protective properties were assessed in human platelets and their fatty acid (FA) content was evaluated by LC-MS. Sensory tests were performed using napping followed by check-all-that apply (CATA). Mild temperatures (52 °C, 65 °C) did not affect the inhibitory effect of PL from brined and un-brined salmon, against human platelet aggregation induced by platelet-activating factor (PAF), thrombin, adenosine diphosphate (ADP) or collagen. In higher temperatures used for pasteurization (80 °C), a reduction of antithrombotic properties was observed in PL from both un-brined and brined salmon samples. This reduction was accompanied by a decrease of their n3 eicosapentaenoic acid (EPA) and overall polyunsaturated FA (PUFA) content, but only in the PL of the un-brined salmon preparations. Thus, changes in the fatty acid content of PL of all sous vide salmon preparations, and especially of specific PUFA, seem to be associated with the observed changes in their antithrombotic potency. Changes in the content of the n-3 docosapentaenoic acid (DPA), a precursor of EPA and docosahexaenoic acid (DHA), seem to be associated with differences observed in the antithrombotic potency of PL from different sous vide salmon preparations. Taste attributes were not affected by the conditions of sous-vide preparations, whereas slight textural differences were observed in samples treated at 65 °C and 80 °C. These outcomes, if combined with the observed low values of the n-6/n-3 PUFA ratio in PL of all sous-vide preparations, further suggest a beneficial role for such a mild cooking procedure for preserving the antithrombotic and cardio-protective properties of salmon without affecting its sensory characteristics.

Evaluation of sensory and in vitro anti-thrombotic properties of traditional Greek yogurts derived from different types of milk.

Given that fermented dairy products exhibit high bioactivities against cardiovascular diseases (CVDs), the anti-thrombotic properties, fatty acid profiles and sensory properties of cow, goat and ewe derived Greek yogurts have been assessed and compared. The total lipids (TL), total polar lipids (TPL), total neutral lipids (TNL) were obtained and the polar lipid fractions were further separated by thin layer chromatography (TLC). These lipid samples (TL, TPL and TLC fractions) were subsequently assessed for their biological activity against atherosclerosis based on the in vitro inhibition of Platelet Activating Factor (PAF)-induced platelet aggregation. The fatty acid compositions of all yogurts were analyzed by Gas Chromatography with flame ionization detector (GC-FID). Goat yogurt lipids have been found to exert more potent inhibitory activity (i.e. lower IC50 values in both TL and TPL samples) in contrast to the corresponding fractions of cow and ewe yogurts. The observed sensory data indicates that ewe yogurt was the most palatable of all three Greek yogurts.

Novel flavours paired with glutamate condition increased intake in older adults in the absence of changes in liking.

Previous research on the repeat exposure to a novel flavour combined with monosodium glutamate (MSG) has shown an increase in liking and consumption for the particular flavour. The aim of the current work was to investigate whether this could also be observed in the case of older people, since they are most affected by undernutrition in the developed world and ways to increase consumption of food are of significant importance for this particular age group. For this study, 40 older adults (age 65-88) repeatedly consumed potato soup with two novel flavours (lemongrass and cumin) which were either with or without a high level of MSG (5% w/w). A randomized single blind within-subject design was implemented, where each participant was exposed to both soup flavours three times over 6 days, with one of the soup flavours containing MSG. After three repeat exposures, consumption increased significantly for the soups where the flavours had contained MSG during the repeated exposure (mean weight consumed increased from 123 to 164 g, p = 0.017), implying that glutamate conditioned for increased wanting and consumption, despite the fact that the liking for the soup had not increased.

Contributions of non-volatile and volatile compounds to the umami taste and overall flavour of shiitake mushroom extracts and their application as flavour enhancers in cooked minced meat.

Aqueous extracts of dried shiitake mushrooms (Lentinus edodes) were prepared as taste and flavour enhancers for meat formulations. Effects of time and temperature on the chemical and sensory properties of the extracts were examined. Extracts prepared at 70°C had significantly higher concentrations (p<0.001) of the savoury tasting 5'-ribonucleotides than those prepared at 22°C but increasing the extraction time from 30 to 360 min only increased their recovery slightly (p=0.053). In contrast, higher temperature extracts had considerably smaller concentrations of the major volatile compounds, such as lenthionine, 1-octen-3-ol, 1,3-dithiethane and dimethyl disulfide, because of loss through volatilisation. A sensory discrimination test showed that the lower temperature extract was perceived to have less umami taste than the higher temperature extract (p=0.048). Incorporating the 70°C shiitake extract into minced meat formulations led to significantly higher levels of savoury tasting 5'-ribonucleotides in the cooked meat but no significant difference in umami perception.

Maximising umami taste in meat using natural ingredients: effects on chemistry, sensory perception and hedonic liking in young and old consumers.

BACKGROUND: Umami taste in foods is elicited predominantly by the presence of glutamic acid and 5'-ribonucleotides, which act synergistically. This study aimed to use natural ingredients to maximise umami taste of a meat formulation and determine effects on liking of older consumers. Cooked meat products with added natural ingredients (yeast extract, mycoscent, shiitake extract, tomato puree, soy sauce and soybean paste) or monosodium glutamate (MSG) were prepared and compared with a control sample analytically (umami compounds), sensorially (sensory profile) and hedonically (liking by younger and older volunteers). Taste detection thresholds of sodium chloride and MSG of volunteers were collected. RESULTS: Four of the seven cooked meat products developed had a significantly higher content of umami-contributing compounds compared with the control. All products, except those containing MSG or tomato puree, were scored (by trained sensory panel) perceptually significantly higher in umami and/or salty taste compared with the control. Consumer tests showed a correlation of liking by the older cohort with perceived saltiness (ρ = 0.76). CONCLUSION: The addition of natural umami-containing ingredients during the cooking of meat can provide enhanced umami and salty taste characteristics. This can lead to increased liking by some consumers, particularly those with raised taste detection thresholds.

Separation of astaxanthin from cells of Phaffia rhodozyma using colloidal gas aphrons in a flotation column.

The aim of this study is to investigate the separation of astaxanthin from the cells of Phaffia rhodozyma using colloidal gas aphrons (CGA), which are surfactant stabilized microbubbles, in a flotation column. It was reported in previous studies that optimum recoveries are achieved at conditions that favor electrostatic interactions. Therefore, in this study, CGA generated from the cationic surfactant hexadecyl trimethyl ammonium bromide (CTAB) were applied to suspensions of cells pretreated with NaOH. The different operation modes (batch or continuous) and the effect of volumetric ratio of CGA to feed, initial concentration of feed, operating height, and flow rate of CGA on the separation of astaxanthin were investigated. The volumetric ratio was found to have a significant effect on the separation of astaxanthin for both batch and continuous experiments. Additionally, the effect of homogenization of the cells on the purity of the recovered fractions was investigated, showing that the homogenization resulted in increased purity. Moreover, different concentrations of surfactant were used for the generation of CGA for the recovery of astaxanthin on batch mode; it was found that recoveries up to 98% could be achieved using CGA generated from a CTAB solution 0.8 mM, which is below the CTAB critical micellar concentration (CMC). These results offer important information for the scale-up of the separation of astaxanthin from the cells of P. rhodozyma using CGA.