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41.
The world market for functional foods has grown dynamically and China is expected to be one of the most promising markets. But little is understood the formation mechanisms of consumers’ purchase attitude and intention toward functional foods in Mainland China. The current study investigates the roles of trust, health consciousness and price in shaping consumers’ purchase intention toward functional foods by focusing on purchase attitude as a mediator and food neophobia as a moderator. Results from the sample of 1144 Chinese suggest that Chinese consumers had moderate purchase intention toward functional foods. Trust in the food system and health consciousness positively affects purchase intention via purchase attitude. Price negatively affects purchase intention; meanwhile, the negative effect could be counteracted by health consciousness. Food neophobia does not directly affect individuals’ purchase attitude or intention, but moderates the relationships between antecedents and them. Consumers with a low level of food neophobia treat higher price as a monetary sacrifice, while their counterparts may regard a higher price as a greater quality signal. The study offers the food industry insights into the development and marketing of functional foods targeted to the Mainland China market.  相似文献   
42.
One of the most important spoilage factors of foods is molds. Therefore, it is important to determine the presence of mold in foods quickly because of the deterioration of aroma, flavor, appearance, and textural structure as well as the mycotoxins, which are toxic secondary metabolites of molds. Twenty-five percent of agricultural products worldwide are infected with mycotoxins directly or indirectly. With the global population increasingly rising, the need for access of safe and adequate food in the future has great importance. Quantification of ergosterol, a constituent of the membrane of molds and a precursor of vitamin D2, is a feasible method for determination of fungal contamination in foods. The aim of this review is to discuss the possibility of using ergosterol as an indicator of mold growth in foods.  相似文献   
43.
Processed foods are popular and their consumption is expected to grow globally. Food processing and manufacturing promote lipid oxidation in foods rich in polyunsaturated fatty acids and cholesterol. This review focuses on how various food manufacturing/processing techniques promote lipid oxidation in grains, meats and meat products, dairy and fats/oils. This review also considers emerging evidence from animal and human studies that suggest a link between dietary oxidised lipid consumption and chronic disease risk. An update on novel food technologies that limit food lipid oxidation is discussed so as to inform both food scientists and dietitians/nutritionists to direct future efforts in not only continuing to bring these novel technologies to the market place but also conduct clinical trials to establish their role in human health.  相似文献   
44.
Only 50%–60% of total seafood catch is used for human consumption, seafood processing being considered as one of the main sources of by-products. Among marine species, jumbo squid (JS; Dosidicus gigas) represents the most important squid fishery, showing an increasing economic interest in many countries. As for any other marine species, the regular cleaning, dressing and processing produce high quantities of by-products (skin, head, fins, viscera, tentacles, unclaimed mantle, etc.) that are rich in many nutrients (proteins, lipids, minerals, vitamins, enzymes, biopolymers, etc.). This review compiles information about extraction and employment of JS by-products with the aim of enhancing their economic value and reduce environmental drawbacks. A special emphasis is given to the relevance in developing methods susceptible to transform by-products into useful and profitable products susceptible to be applied in several industries such as food, medicine, agrochemical or pharmaceutical. Future possible trends for widening this profitable use are mentioned.  相似文献   
45.
Six olive oils extracted from the cultivars Arbequina, Arbosana, Coratina, Frantoio, Koroneiki, and Picual from 2017 and 2018 harvests, cultivated in Pinheiro Machado, Rio Grande do Sul, Brazil, are evaluated for standard oil composition parameters and bioactive constituents (pigments, tocopherols, and phenolic compounds). Multivariate principal component analysis (PCA) and univariate ANOVA and Fisher's LSD test are used to verify the effect of cultivar and harvest year on oil composition. Olive oil composition met extra virgin olive oil (EVOO) standard parameters and is influenced by both cultivar and harvest year. EVOO produced in 2018 has greater chlorophyll, caffeic acid, ligstroside aglycone, hydroxyoleuropein aglycone, syringic acid, and hydroxytyrosol acetate contents than the EVOOs from 2017. Linoleic acid, ferulic acid, ligstroside aglycone, and hydroxytyrosol acetate are the variables whose contents most contributed to the differentiation of oils by cultivar in both harvest years. Chemical characterization analyses allow for the differentiation of oil composition based on harvest year and cultivar. Metabolic quality data obtained here support the establishment of a local EVOO profile and the compounds that most contributed to treatment differentiation may serve as markers that can be utilized in determining origin, cultivar, and harvest year. Practical Applications: Olive production in Brazil is recent and is based on European cultivars which have not been bred for the local environmental conditions. Therefore, the measurement of olive oil metabolic quality will determine cultivar adaptability to local edaphoclimatic conditions as well as assist in the establishment of a standard of identity for the product and promote the development of its market. Olive oil produced in Southern Brazil shows high quality, and is especially rich in phenolic compounds. Although harvest year influences oil composition, oil from both harvests meet EVOO standards and cultivar specific metabolic markers are observed. This study provides the foundation for olive producers in Southern Brazil to seek authentication of the geographical origin of olive oil.  相似文献   
46.
Under normal physiological conditions the brain primarily utilizes glucose for ATP generation. However, in situations where glucose is sparse, e.g., during prolonged fasting, ketone bodies become an important energy source for the brain. The brain’s utilization of ketones seems to depend mainly on the concentration in the blood, thus many dietary approaches such as ketogenic diets, ingestion of ketogenic medium-chain fatty acids or exogenous ketones, facilitate significant changes in the brain’s metabolism. Therefore, these approaches may ameliorate the energy crisis in neurodegenerative diseases, which are characterized by a deterioration of the brain’s glucose metabolism, providing a therapeutic advantage in these diseases. Most clinical studies examining the neuroprotective role of ketone bodies have been conducted in patients with Alzheimer’s disease, where brain imaging studies support the notion of enhancing brain energy metabolism with ketones. Likewise, a few studies show modest functional improvements in patients with Parkinson’s disease and cognitive benefits in patients with—or at risk of—Alzheimer’s disease after ketogenic interventions. Here, we summarize current knowledge on how ketogenic interventions support brain metabolism and discuss the therapeutic role of ketones in neurodegenerative disease, emphasizing clinical data.  相似文献   
47.
This review summarises 25 years of investigations on antioxidants research in foods and biological fluids and critically analyses the merits and limitations of using the total antioxidant capacity (TAC) measurement in the metabolomic era. An enormous bulk of knowledge was produced regarding the antioxidant capacity of foods and large TAC databases were developed. A direct link between a food TAC value and any health benefit is erroneous and has led to several cases of consumer deception. However, the striking epidemiological evidence associating a high dietary TAC with some disease prevention and the availability of well-constructed TAC databases deserve attention and must be taken into account to establish the usefulness of measuring TAC in both foods and biological samples. The in vivo TAC measurement, usually performed in plasma, is influenced by many external factors, such as dietary habits, as well as environmental and behavioural factors, which are integrated towards homeostatic control by fine physiological mechanisms with high inter-individual variability. Therefore, plasma TAC cannot be considered as a unique biomarker of individual antioxidant status. However, the combined evaluation of plasma TAC with known markers of disease, individual metabolism, inflammation and genetics, as well as with markers of gut microbiota composition and activity, may lead to the identification of populations that are more responsive to food/diet TAC. In this framework, the appropriate use of TAC measurement both in food and in vivo can still provide support for the interpretation of complex phenomena and be a tool for sample screening when making a quick decision toward in-depth research investigations. © 2018 Society of Chemical Industry  相似文献   
48.
Temperature-sensitive polyurethane (TSPU) films incorporated with carvacrol and cinnamyl aldehyde were prepared for the potential use of food packaging. The antimicrobial properties and sustained release kinetics of carvacrol and cinnamyl aldehyde in TSPU film were investigated. Results indicated that cinnamyl aldehyde and carvacrol had favourable antimicrobial properties at relatively low addition ratio. The diffusion and release of carvacrol were linearly related to temperature and its addition ratio. The release rates of carvacrol from TSPU film increased from 0.6% to 2.2% with the increase of addition ratio and temperature. The first-order kinetic equation could be used to describe its diffusion and sustained release process. TSPU films could significantly prolong the shelf life of Cantonese-style moon cakes by effectively inhibiting microbial growth and decreasing lipid oxidation comparing with commonly used polyethylene food packaging. Results obtained in the present work can provide technical guide of sustained release food packaging films with antimicrobial properties.  相似文献   
49.
目的研究纳米氧化锌/低密度聚乙烯膜(low density polyethylene film,LDPE)中锌(Zn)向食品的迁移行为,探究其迁移规律。方法选取2种食品模拟物(3%乙酸及超纯水)及真实食品(食用白醋及瓶装水),在3种不同实验温度下(70、40及20℃),研究锌向食品模拟物的迁移规律。采用扫描电子显微镜(scanning electron microscope,SEM)和原子力显微镜(atomic force microscope,AFM)表征纳米ZnO/LDPE膜的表面形貌。结果锌向酸性模拟物中的迁移率远远大于水性模拟物中的迁移率,其中锌向酸性模拟物中的最大迁移率分别为22.7%,20.3%及18.6%(ZL-1,ZL-2及ZL-2#),向水性模拟物中的最大迁移率分别为9.9%,5.7%及4.9%(ZL-1,ZL-2及ZL-2#);锌向酸性食品的迁移量(1.59~5.03 mg/g)同样高于向水性食品的迁移量(2.98~24.60μg/g);随着纳米ZnO的初始含量变大迁移率变小;而偶联剂的加入对锌的迁移有一定的抑制作用。随着纳米ZnO浓度的增加,在薄膜中观察到纳米ZnO的不规则形貌。结论纳米ZnO/LDPE膜不适合在高温下包装食物,且其在酸性食品中的安全隐患高于水性食品。  相似文献   
50.
The long-established use of enzymes for food processing and product formulation has resulted in an increased enzyme market compounding to 7.0% annual growth rate. Advancements in molecular biology and recognition that enzymes with specific properties have application for industrial production of infant, baby and functional foods boosted research toward sourcing the genes of microorganisms for enzymes with distinctive properties. In this regard, functional metagenomics for extremozymes has gained attention on the premise that such enzymes can catalyze specific reactions. Hence, metagenomics that can isolate functional genes of unculturable extremophilic microorganisms has expanded attention as a promising tool. Developments in this field of research in relation to food sector are reviewed.  相似文献   
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