Stability of the phenolic compounds and antioxidant capacity of five fruit (apple,orange, grape,pomelo and kiwi) juices during in vitro‐simulated gastrointestinal digestion

The in vitro digestive stability of phenolic compounds and the antioxidant capacity of five kinds of commonly consumed fruit juices in the daily diet, including apple juice (AJ), orange juice (OJ), grape juice (GJ), pomelo juice (PJ) and kiwifruit juice (KJ), were studied. Following in vitro digestion, the total phenolic (TP) content of fruit juices decreased to different extents by 35%, 25.3%, 23.5%, 22.2% and 7.8% for KJ, OJ, PJ, GJ and AJ, respectively. The individual phenolic content showed similar changes to the TP content, showing reductions of naringenin‐trisaccharide in OJ and PJ, epicatechin in GJ, and chlorogenic acid in AJ by 43.74%, 27.59%, 47.11% and 33.28%, respectively. Conversely, the antioxidant capacity of fruit juices during digestion measured by ABTS assay increased from 4.79% to 35.53%, except in KJ, which decreased by 19.34%. These results show the health benefits of fruit juices after processing and contribute towards establishing suitable dietary recommendations.     

Impact of 100% Fruit Juice Consumption on Diet and Weight Status of Children: An Evidence-based Review

Consumption of 100% fruit juice remains controversial for its potential adverse impact on weight and displacement of essential foods in the diets of children. A systematic review of the literature published from 1995–2013 was conducted using the PubMed database to evaluate associations between intake of 100% fruit juice and weight/adiposity and nutrient intake/adequacy among children of 1 to 18 years of age. Weight status outcome measures included body mass index (BMI), BMI z-score, ponderal index, obesity, weight gain, adiposity measures, and body composition. Nutrient outcome measures included intake and adequacy of shortfall nutrients. Data extraction and analysis was conducted according to the Academy of Nutrition and Dietetics Evidence Analysis Process. Twenty-two studies on weight status provided evidence that did not support an association between 100% fruit juice consumption and weight/adiposity in children after controlling for energy intake. Limited evidence from eight studies suggests that children consuming 100% fruit juice have higher intake and adequacy of dietary fiber, vitamin C, magnesium, and potassium. Differences in methodology and study designs preclude causal determination of 100% fruit juice as sole influencer of weight status or nutrient intake/adequacy of shortfall nutrients. In context of a healthy dietary pattern, evidence suggests that consumption of 100% fruit juice may provide beneficial nutrients without contributing to pediatric obesity.     

Patulin in fruit juices: occurrence,bioaccessibility, and risk assessment for Serbian population

This paper reports the first study of patulin occurrence in fruit juices and risk assessment related to patulin intake by children, adolescents and adults in Serbia. During 3 consecutive years (2013–2015), 142 fruit (apple or multi-fruit) juices were collected from the market and analysed using HPLC-UV. Patulin was found in 51.4% of juices with 0.7% of the samples in excess of the legal limit of 50 μg kg^?1 (mean 4.3 μg kg^?1). Apple juices showed significantly higher percentage of contaminated samples (74.0% vs 27.5%), as well as higher mean patulin content (6.4 vs 2.1 μg kg^?1) when compared with the multi-fruit ones. Bioaccessibility of patulin in fruit juices was studied using the standardised in vitro digestion method. A mean of 21.6% of the initial patulin amount reached the end of the intestinal phase showing a significant reduction of this toxin during the human digestion process. Risk assessment of patulin intake by Serbian children, adolescents and adults, conducted by deterministic and probabilistic approaches and including the bioaccessibility results, revealed no health concern. Although patulin alone does not represent risk, further research should consider its co-occurrence with other toxic substances in food and potential adverse effects of their mixtures.     

A review of limonin in grapefruit (Citrus paradisi) juice,its relationship to flavour,and efforts to reduce it

Ever since limonin was first discovered in grapefruit (Citrus paradisi Macf) juice in 1965 and found responsible for significantly contributing to bitterness in the juice, a great deal of research has been directed towards understanding its role therein. Information is presented relative to limonin's chemical determination, taste threshold and content in grapefruit juice, and to relevant legislation. Also considered are (1) several factors affecting the limonin content of grapefruit juice (2) the effect of limonin content on sensory flavour in grapefruit juice (3) the interaction between the Brix: acid ratio and limonin content in affecting grapefruit juice flavour and (4) methods for reducing limonin in citrus juices generally. Finally, recommendations for future studies on limonin in grapefruit juice are reviewed.     

Sensory Perception,Nutritional Role,and Challenges of Flavored Milk for Children and Adults

Milk and milk products provide essential nutrients for both adults and children. However, overall milk consumption of both adults and children does not meet the recommendations from Dietary Guidelines for Americans. Flavored milk can increase milk consumption for children and adolescents, but the added sugar content raises concern. Since the removal or reduction of flavored milk decreases milk consumption for children, it is important to understand all aspects of flavored milk in order to increase milk consumption while minimizing sugar intake. This review will address adult and children perception of flavored milk as well as its nutrition, regulations in school meal programs, and challenges. Understanding the sensory perception of both adults and children for flavored milk can help food developers and manufacturers to address attractive attributes while reducing the sugar content to meet the needs of a healthy diet.     

Non-targeted metabolomic approach reveals urinary metabolites linked to steroid biosynthesis pathway after ingestion of citrus juice

Citrus juice intake has been highlighted because of its health-promoting effects. LC–MS based metabolomics approaches are applied to obtain a better knowledge on changes in the concentration of metabolites due to its dietary intake and allow a better understanding of involved metabolic pathways. Eight volunteers daily consumed 400 mL of juice for four consecutive days and urine samples were collected before intake and 24 h after each citrus juice intake. Urine samples were analysed by nanoHPLC-q-TOF, followed by principal component analysis (PCA) and Student’s t-test (p < 0.05). PCA showed a separation between two groups (before and after citrus juice consumption). This approach allowed the identification of four endocrine compounds (tetrahydroaldosterone-3-glucuronide, cortolone-3-glucuronide, testosterone-glucuronide and 17-hydroxyprogesterone), which belonged to the steroid biosynthesis pathway as significant metabolites upregulated by citrus juice intake. Additionally, these results confirmed the importance of using the non-targeted metabolomics technique to identify new endogenous metabolites, up- or down-regulated as a consequence of food intake.     

Chemical Characterization of Orange Juice from Trees Infected with Citrus Greening (Huanglongbing)

ABSTRACT: The effects due to Candidatus Liberibacter infection, commonly called citrus greening or Huanglongbing (HLB), on volatile and nonvolatile components of orange juices, OJ, were examined using GC-MS and high-performance liquid chromatography (HPLC). HLB symptomatic, asymptomatic, and control “Hamlin” and “Valencia” oranges were harvested from December to May during the 2007 to 2008 harvest season. Brix/acid levels in control and asymptomatic juices were similar but symptomatic juices were as much as 62% lower than control juices. No bitter flavanone neohesperidosides were detected and polymethoxyflavone concentrations were well below bitter taste thresholds. Limonin concentrations were significantly higher (91% to 425%) in symptomatic juice compared to control but still below juice bitterness taste thresholds. Juice terpenes, such as γ-terpinene and α-terpinolene, were as much as 1320% and 62% higher in symptomatic juice than control. Average ethyl butanoate concentrations were 45% lower and average linalool was 356% higher in symptomatic Valencia OJ compared to control. Symptomatic Valencia OJ had on average only 40% the total esters, 48% the total aldehydes, and 33% as much total sesquiterpenes as control juice. Total volatiles between control and symptomatic juices were similar due to elevated levels of alcohols and terpenes in symptomatic juice. There were no consistent differences between asymptomatic and control juices. The chemical composition of juice from HLB/greening symptomatic fruit appears to mimic that of juice from less mature fruit. The reported off-flavor associated with symptomatic juices probably stem from lower concentrations of sugars, higher concentrations of acid as all known citrus bitter compounds were either below taste thresholds or absent.     

Portable, low-cost equipment for small-scale fruit juice processing

Simple, low-cost portable equipment to extract citrus juice, and pasteurize it and other fruit juices by passing through a coil of stainless steel tube in boiling water was designed, constructed and tested. Temperature reached was varied by altering the hydrostatic feed height, and the product was directly hot-bottled and capped. Pasteurization was microbiologically effective, and had little effect on ascorbic acid, furfural and colour of freshly prepared pineapple orange, Valencia orange and apple juices, and an orange squash drink, and only the expected changes occurred on storage at 21°C for periods up to 6 months, although with no indication of microbial activity. Taste panel ratings showed a loss of liking for treated orange juice, but not for apple. The equipment is suitable for improved utilization of crops by community technology in less-developed areas.     

A review of pectin methylesterase inactivation in citrus juice during pasteurization

BackgroundPectin, naturally found in citrus, plays a key role in the quality of the obtained juices. Pectin methylesterase enzyme (PME) influences the cloud stability, viscosity, color, mouth feeling and flavor of the juices by de-esterification of pectin. Iinactivation of PME is introduced as a pasteurization index in citrus juices, due to its higher thermal resistance than the spoilage microorganisms.Scope and approachInactivation of PME using different thermal (conventional, microwave and ohmic heating) and non-thermal (pulsed electric field, high pressure processing and high pressure carbon dioxide) processes is important in juice production. The aim of this study was to review the effect of these processing methods on the PME inactivation in different citrus juices.Key finding and conclusionUsing non-thermal methods in combination with moderate thermal methods can be more effective in PME inactivation with minimum loss in citrus juice quality.     

The Role of Dairy Products in Healthy Weight and Body Composition in Children and Adolescents

Overweight and obesity are major public health concerns with approximately 32% and 17% of U.S. children aged 2 - 19 being classified as overweight or obese, respectively. While the cause of overweight and obesity is multi-factorial, changes in eating habits and physical activity patterns have been proposed as contributing factors to the obesity epidemic. For example, the displacement of nutrient rich foods and beverages with non-nutrient dense items may be influencing childhood obesity. Many children do not consume the recommended servings of the Food Groups to Encourage, i.e. low-fat and fat-free dairy foods, fruits, vegetables, and whole grains identified by the 2005 Dietary Guidelines for Americans which results in low intakes of calcium, potassium, fiber, magnesium, and vitamin E. While attention has focused primarily on reducing energy intake and/or increasing energy expenditure for weight maintenance, a promising beneficial role for dairy products in weight management has emerged. Most research has focused on adults, but there is evidence in children and adolescents indicating either a beneficial or neutral effect of dairy food consumption on body weight or body composition. The current review provides and assessment of the scientific evidence on the effects of dairy food consumption on body weight and body composition in children and adolescents.     

柑橘类果汁混浊稳定化研究进展

柑橘类果汁的混浊稳定状态是其品质评价的重要指标，也是柑橘类果汁加工技术中的关键。综述了柑橘类果汁中混浊体系的组分构成及功能，柑橘类果汁的混浊稳定状态的各类影响因素以及加工生产中维持混浊稳定方法等方面的研究进展．以期为柑橘类果汁的混浊稳定问题的解决提供参考依据。     

柑桔汁中的果胶酯酶及其钝化特性

果胶酯酶（ＰＥ或ＰＭＥ）的活性是导致柑桔汁混浊态的丧失的主要原因,因此研究其理化性质,钝化其活性对提高柑桔汁质量意义重大。介绍了柑桔汁中果胶酯酶的性质及钝化其活性的一些措施。     

柑橘类果汁脱苦技术研究进展

柚皮苷和类柠檬苦素是柑橘类果汁的主要苦味物质,其存在明显影响了柑橘类果汁的品质。介绍了脱除柑橘类果汁苦味的一些技术：代谢脱苦、吸附脱苦、酶法脱苦、屏蔽法脱苦、分离技术脱苦和基因脱苦等。     

Raspberry juice consumption, oxidative stress and reduction of atherosclerosis risk factors in hypercholesterolemic golden Syrian hamsters

The effects of raspberries on early atherosclerosis in Syrian hamsters were investigated using three juices prepared from var. Cardinal, Glen Ample and Tulameen berries. The hamsters received an atherogenic diet for 12 weeks and at the same time a juice at a daily dose corresponding to the consumption of 275 ml by a 70 kg human. A control group received the same diet with water instead juice. The principal polyphenolic compounds in the juices were anthocyanins and ellagitannins, which were present at concentrations of 218-305 μg mL(-1) and 45-72 μg mL(-1), respectively. The three juices had similar but not identical effects. They all inhibited cardiac and aortic production of superoxide anion and increased hepatic glutathione peroxidase activity although only Tulameen juice brought about a significant increase in superoxide dismutase activity. Glen Ample was the only juice to significantly increase plasma paraoxonase activity. All the juices lowered plasma triglyceride level while consumption of Tulameen and Cardinal, but not Glen Ample, significantly lowered plasma total cholesterol and LDL-cholesterol. Cardinal was the sole juice to significantly increase HDL-cholesterol and likewise it also significantly reduced body weight. These findings suggest that moderate consumption of raspberry juices can help to prevent the development of early atherosclerosis, with the underlying mechanisms related to improved antioxidant status and serum lipid profiles.     

Concentration of morpholine residues in major fruits and juices and its dietary exposure in China

Morpholine is a common chemical used as emulsifier in the preparation of wax coatings for some fruit to help them remain fresh and protect against insects and fungal contamination. It has been reported that morpholine has acute toxic effects on rodents. In the present study, morpholine concentrations were analysed in fruits (citrus fruits, apples, strawberries and grapes) and juices (apple juice and orange juice) in order to determine dietary exposure among the Chinese population. A total of 732 fruit and juice samples were collected during 2015–2016, which covered major foods in China. Fruit and juice consumption data were taken from China National Nutrient and Health Survey (2002) and include data from 16,407 fruit or juice consumers. It was found that mean dietary exposure to morpholine residues from fruits and/or juices for general Chinese consumers and children 2–6 years old were 0.42 and 1.24 µg/kg bw/day, respectively. The 97.5% intake in general Chinese consumers and children 2–6 years old were 2.25 and 6.90 µg/kg bw/day, respectively. The primary food sources of the morpholine dietary intake of general Chinese consumers were citrus fruits (57.4%) and apples (40.8%). These findings suggested that dietary exposure to morpholine in the Chinese population was lower than the acceptable daily intake of morpholine, and there are no health concerns.     

Kinetic Models for Thermal Inactivation of Multiple Pectinesterases in Citrus Juices

First-order kinetic model of a two-component system was applied to investigate heat inactivation of multiple pectinesterases in citrus juices. The conventional log-linear model was applied to determine D- and z-values of thermolabile and thermostable pectinesterases in citrus juices, respectively, for use in the two-component model. A parameter for concentration of enzyme populations in the juice was included in the model. The two-component model predicted results were in better agreement with the observed heat pasteurization curves than those predicted by the log-linear kinetic model. The two-component model is especially useful for optimizing temperature-time conditions for pasteurizing citrus juices.     

柑橘类果汁脱苦的研究进展

柑橘类果汁中苦味物质主要由柠檬苦素，柚皮苷等组成。对柑橘类果汁脱苦的代谢法、吸附法等9种方法进行了综述。     

Satisfying America's Fruit Gap: Summary of an Expert Roundtable on the Role of 100% Fruit Juice

The 2015 to 2020 Dietary Guidelines for Americans (DGAs) recognize the role of 100% fruit juice in health and in helping people meet daily fruit recommendations and state that 100% fruit juice is a nutrient‐dense beverage that should be a primary choice, along with water and low‐fat/fat‐free milk. The DGAs note that children are consuming 100% fruit juice within recommendations (that is, 120 to 180 mL/d for children aged 1 to 6 y and 236 to 355 mL/d for children aged 7 to 18 y). Evidence shows that compared to nonconsumers, those who consume 100% fruit juice come closer to meeting daily fruit needs and have better diet quality. In children, 100% fruit juice is associated with increased intakes of nutrients such as vitamin C, folate, and potassium. When consumed within the DGA recommendations, 100% fruit juice is not associated with overweight/obesity or childhood dental caries and does not compromise fiber intake. Preliminary data suggest that polyphenols in some 100% fruit juices may inhibit absorption of naturally occurring sugars. Given its role in promoting health and in helping people meet fruit needs, experts participating in a roundtable discussion agreed that there is no science‐based reason to restrict access to 100% fruit juice in public health nutrition policy and programs such as the Special Supplemental Nutrition Program for Women, Infants, and Children (WIC). Reducing or eliminating 100% fruit juice could lead to unintended consequences such as reduced daily fruit intake and increased consumption of less nutritious beverages (for example, sugar‐sweetened beverages).     

Hedonic tests in different locations as predictors of apple juice consumption at home in elderly and young subjects

The objective of this study was to evaluate the predictive value of hedonic tests on apple juice carried out in a sensory laboratory, University common room and at home (post-consumption test) on ad libitum home consumption measured over 5 consecutive days. Thirty-five elderly volunteers (59–88 years old) and 33 young subjects (20–30 years old) assessed the degree of liking five apple juices varying in sweetness (0, 2, 4, 7 and 10% w/w sucrose added) on a nine-point hedonic scale. Both age groups judged similarly the juice with the lowest sugar concentrations, whereas the juice with 2% sugar added received lower scores from the elderly compared to the young participants. Those samples with higher sweetness (4, 7 and 10%) received higher scores from the elderly compared to the young people. The sample with no sugar added had higher mean score (all the subjects) in the home test (6.92±1.78) compared to both laboratory (5.51±2.15) and common room (5.92±2.08). No such differences were observed for the juices with the other sugar contents. In the elderly group, 1-day intake of apple juice remained on a similar level, regardless of sweetness liking, while among young adults the intake varied, and was highest for juices that were liked most (with 0 and 2% sucrose added). The results showed that hedonic ratings have a limited value as predictors of fruit juice consumption at home. The correlation between rated degree of liking and intake was low, especially for the elderly (r=0.39), indicating that factors other than pleasantness may affect intake. Among three test conditions, the lowest correlation of juice intake was obtained with laboratory test results (r=0.38), relatively higher—when hedonic tests were conducted in common room setting (r=0.49), or as the post-consumption test at home (r=0.73). Further research is required on sensory procedures relevant for the elderly, which together with some other nonsensory factors, would give a better prediction of consumption.