Evaluating the crystallization of lactose at different cooling rates from milk and whey permeates in terms of crystal yield and purity

The cooling rate of supersaturated lactose solution is one of the important parameters determining the yield and size distribution of lactose crystals. The influence of increasing cooling rate on lactose crystallization and quality of lactose crystals was evaluated in concentrated solutions prepared from deproteinized whey powder (DPW) and milk permeate powder (MPP). Concentrated permeates (DPW and MPP) with 60% (wt/wt) total solids were prepared by reconstituting permeate powders in water at 80°C for 2 h for lactose dissolution. Three cooling rates, 0.04°C/min (slow), 0.06°C/min (medium), and 0.08°C/min (fast) were studied in duplicate. A common rapid cooling step (80 to 60°C at 0.5°C/min) followed by slow, medium, and fast cooling rates were applied as per the experimental design from 60 to 20°C. After crystallization, the crystal slurry was centrifuged, washed with cold water, and dried. The dried lactose crystals were weighed to calculate the lactose yield. Final mean particle chord lengths were measured at the end of crystallization using focused beam reflectance measurement for slow, medium, and fast cooling rates, and observed to be not significantly different for DPW (27–33 µm) and MPP (31–34 µm) concentrates. Similarly, the lactose yield for slow, medium, and fast cooling rates in the DPW and MPP concentrates were in the range of 71 to 73% and 76 to 81%, respectively, and no significant difference between the 3 cooling rates was found. Qualitative analysis of dried lactose crystals exhibited no noticeable differences in the crystal purity with increasing cooling rate. This study evaluated the possibility of reducing the crystallization times by 8 h compared with current industrial practice without compromising the crystal yield and quality.     

Short communication: Composition of coproduct streams from dairy processing: Acid whey and milk permeate

This article provides composition information for 3 abundantly available but little characterized dairy coproduct streams: acid whey from Greek yogurt (GAW), acid whey from cottage cheese (CAW), and milk permeate (MP). Three replicate samples obtained on different dates from several dairy processors were analyzed. The main component in all streams was lactose, with up to 3.5, 2.1, and 11.9% in GAW, CAW, and MP, respectively. Crude protein content ranged from 1.71 to 3.71 mg/g in GAW, 1.65 to 5.05 mg/g in CAW, and 3.2 to 4.35 mg/g in MP, and pH ranged from 4.21 to 4.48, 4.35 to 4.51, and 5.4 to 6.37, respectively. Chemical oxygen demand varied from 52,400 to 62,400 mg/L for GAW, 31,900 to 40,000 mg/L for CAW, and 127000 to 142,000 mg/L for MP; biochemical oxygen demand ranged from 45,800 to 50,500 mg/L (GAW), 32,700 to 40,000 mg/L (CAW), and 110,000 to 182,000 mg/L (MP). The GAW had the lowest pH (4.21–4.48) and highest mineral content of all streams. These data will assist processors and researchers in developing value-added uses of these dairy coproducts.     

Glycolipid biosurfactants: main properties and potential applications in agriculture and food industry

Glycolipids, consisting of a carbohydrate moiety linked to fatty acids, are microbial surface active compounds produced by various microorganisms. They are characterized by high structural diversity and have the ability to decrease the surface and interfacial tension at the surface and interface, respectively. Rhamnolipids, trehalolipids, mannosylerythritol lipids and cellobiose lipids are among the most popular glycolipids. They have received much practical attention as biopesticides for controlling plant diseases and protecting stored products. As a result of their antifungal activity towards phytopathogenic fungi and larvicidal and mosquitocidal potencies, glycolipid biosurfactants permit the preservation of plants and plant crops from pest invasion. Also, as a result of their emulsifying and antibacterial activities, glycolipids have great potential as food additives and food preservatives. Furthermore, the valorization of food byproducts via the production of glycolipid biosurfactant has received much attention because it permits the bioconversion of byproducts on valuable compounds and decreases the cost of production. Generally, the use of glycolipids in many fields requires their retention from fermentation media. Accordingly, different strategies have been developed to extract and purify glycolipids. © 2016 Society of Chemical Industry     

Lactulose: production and use in functional food,medical and pharmaceutical applications. Practical and critical review

Lactulose is a synthetic disaccharide. It can be obtained from lactose by chemical, enzymatic or by electro‐activation synthesis. This review provides the comprehension of lactulose production and its application in medical, pharmaceutical and functional food applications. Lactulose can be used in medical and pharmaceutical applications for the treatment of diseases such as chronic constipation, therapy of portal systemic encephalopathy, inflammatory bowel disease, reducing blood ammonia levels, colon carcinogenesis, tumour prevention and immunology, mineral absorption and for the inhibition of the secondary bile acid formation. However, with the growing interest in functional foods, the use of nondigestible oligosaccharides such as prebiotic ingredients has increased considerably during the recent years. In this context, lactulose as a well‐recognised prebiotic offers excellent possibilities to develop new functional foods. It can be added to several foods.     

Technical note: Direct enzyme immunoassay of progesterone in bovine milk whey

A simple extraction-free or direct quantitative ELISA for progesterone in bovine milk whey was developed. Whey samples are easy to collect, transport, and store. This method also allows for monitoring progesterone levels in cattle, which is important in reproductive management. The assay was designed to cover the concentration range 0.05 to 2 ng/mL, and the sensitivity of the method was 1.5 pg/mL. The intra- and interassay coefficients of variation were 8 and 12%, respectively. A high correlation (r = 0.90) between ELISA and radioimmunoassay measurements of progesterone in the same milk whey samples was obtained. The method can be easily applied in practice because samples can be stored at room temperature (22 to 26°C) for 4 d. Moreover, because analysis requires milk coagulation, that process can be initiated during transport by standard mail services to the laboratory. Upon arrival at the laboratory, whey can be kept refrigerated for 1 wk before analysis. This tool is useful for monitoring luteal activity of dairy cows.     

减盐、减油、减糖现状与工作对策

作为膳食的重要组成部分,盐、油、糖在满足人的口感与营养的同时,过多摄入可能导致高血压、肥胖、糖尿病、心脑血管疾病等慢性病.减盐、减油、减糖是控制慢性病最经济、最有效的手段,只有政府、企业、专家、媒体等社会各界共同发力,营造良好支持环境,从供给侧、需求侧方面均落实减盐、减油、减糖措施,才能全面遏制慢性病流行的态势.     

Prebiotic Low Sugar Chocolate Dairy Desserts: Physical and Optical Characteristics and Performance of PARAFAC and PCA Preference Map

The addition of prebiotic and sweeteners in chocolate dairy desserts opens up new opportunities to develop dairy desserts that besides having a lower calorie intake still has functional properties. In this study, prebiotic low sugar dairy desserts were evaluated by 120 consumers using a 9‐point hedonic scale, in relation to the attributes of appearance, aroma, flavor, texture, and overall liking. Internal preference map using parallel factor analysis (PARAFAC) and principal component analysis (PCA) was performed using the consumer data. In addition, physical (texture profile) and optical (instrumental color) analyses were also performed. Prebiotic dairy desserts containing sucrose and sucralose were equally liked by the consumers. These samples were characterized by firmness and gumminess, which can be considered drivers of liking by the consumers. Optimization of the prebiotic low sugar dessert formulation should take in account the choice of ingredients that contribute in a positive manner for these parameters. PARAFAC allowed the extraction of more relevant information in relation to PCA, demonstrating that consumer acceptance analysis can be evaluated by simultaneously considering several attributes. Multiple factor analysis reported Rv value of 0.964, suggesting excellent concordance for both methods.     

Valorization of byproducts from tropical fruits: Extraction methodologies,applications, environmental,and economic assessment: A review (Part 1: General overview of the byproducts,traditional biorefinery practices,and possible applications)

Tropical fruits represent one of the most important crops in the world. The continuously growing global market for the main tropical fruits is currently estimated at 84 million tons, of which approximately half is lost or wasted throughout the whole processing chain. Developing novel processes for the conversion of these byproducts into value‐added products could provide a viable way to manage this waste problem, aiming at the same time to create a sustainable economic growth within a bio‐economy perspective. Given the ever‐increasing concern about sustainability, complete valorization through a bio‐refinery approach, that is, zero waste concept, as well as the use of green techniques is therefore of utmost importance. This paper aims to report the status on the valorization of tropical fruit byproducts within a bio‐refinery frame, via the application of traditional methodologies, and with specific attention to the extraction of phenolics and carotenoids as bioactive compounds. The different types of byproducts, and their content of bioactives is reviewed, with a special emphasis on the lesser‐known tropical fruits. Moreover, the bioactivity of the different types of extracts and their possible application as a resource for different sectors (food, pharmaceutical, and environmental sciences) is discussed. Consequently, this review presents the concepts of tropical fruit biorefineries, and the potential applications of the isolated fractions.     

Short communication: Presence of galactose and glucose promotes browning of sweet whey powder

This research examined the role of sugar type on the browning of sweet whey powder during accelerated storage. Two model systems, a lactose-lysine system and a sweet whey powder system, were selected. Within each model system experiment were samples containing equimolar concentrations of lactose, galactose, and glucose, and model systems were studied at 3 pH values: 6.5, 6.0, and 5.5. Samples were analyzed for changes in color after accelerated browning at 80°C for 24 h. The results showed that the samples containing galactose and glucose browned to a greater degree than those containing lactose. Browning in the control and lactose-enriched samples was more susceptible to changes in pH. This study indicates that the processing conditions of liquid whey in which the lactose monomers glucose and galactose accumulate may predispose SWP to brown more readily.     

Potential uses and applications of treated wine waste: a review

Recently, there has been an upsurge in the exploitation of the waste materials generated by the wine industry. Wine waste is characterised by the presence of natural antioxidants much safer than synthetic antioxidants. Wine waste‐derived antioxidants have been recently used in the food industry. Moreover, wine waste can be potentially used as soil conditioner, as adsorbent for heavy metals, for fertiliser and for pullulan production. This review aims at presenting the most important and economically viable applications of treated wine waste.     

Dielectrical properties of food materials--1: factors affecting and industrial uses

The electrical properties of foods and biological products have been the most valuable factors in the novel food technology. They have been defined both from electromagnetic field concepts and from the electrical-circuit point of view. Recently, these properties are used to assess the characterization of the processes based on electrical methods: electromagnetic, electro-processes. This article is a review of dielectrical properties of food materials. It also includes factors affecting the dielectrical properties of foods and their industrial uses.     

苦荞麦面包的加工研究及其降血糖功能初探

以比例为3：7的苦荞麦粉和小麦高筋粉为主要原料，辅以脱脂奶粉、乳化剂、面包改良剂和安赛蜜，采用一次发酵法180℃烘烤出的苦养面包，经高效液相色谱法测定发现：苦荞特有苦香味和功能成分在此条件下被最大限度地保留，且口感适宜。动物喂养实验表明该产品可作为糖尿病人良好的主食替代品。     

The influence of food on food intake: methodological problems and mechanisms of action.

Emphasis has been placed on the understanding of the regulation of food intake in the hope of aiding the battle against obesity and of helping to ameliorate the anorexia of cancer and eating disorders. Available data suggest that the regulatory system is multifaceted and complex. This review focuses on current research on the regulation of appetite and satiety by carbohydrates, fats, and proteins as well as by artificial sweeteners. Some methodological problems and potential mechanisms of action at the biochemical level are discussed. Evidence suggests that organisms are more successful in defending against calorie dilution than in adjusting to increases in calories. The implications of that defense relative to the use of ersatz nutrients are explored.     

Reduced‐sodium cheeses: Implications of reducing sodium chloride on cheese quality and safety

Sodium chloride (NaCl) universally well‐known as table salt is an ancient food additive, which is broadly used to increase the storage stability and the palatability of foods. Though, in recent decades, use of table salt in foods is a major concern among the health agencies of the world owing to ill effects of sodium (Na) that are mostly linked to hypertension and cardiovascular diseases. As a result, food scientists are working to decrease the sodium content in food either by decreasing the rate of NaCl addition or by partial or full replacement of NaCl with other suitable salts like potassium chloride (KCl), calcium chloride (CaCl₂), or magnesium chloride (MgCl₂). However, in cheese, salt reduction is difficult to accomplish owing to its multifaceted role in cheese making. Considering the significant contribution in dietary salt intake (DSI) from cheese, researchers across the globe are exploring various technical interventions to develop reduced‐sodium cheeses (RSCs) without jeopardizing the quality and safety of cheeses. Thus, the purpose of this study is to provide an insight of NaCl reduction on sensory, physicochemical, and technofunctional attributes of RSCs with an aim to explore various strategies for salt reduction without affecting the cheese quality and safety. The relationship between salt reduction and survival of pathogenic and spoilage‐causing microorganisms and growth of RSCs microflora is also discussed. Based on the understanding of conceptual and applied information on the complex changes that occur in the development of RSCs, the quality and safety of RSCs can be accomplished effectively in order to reduce the DSI from cheese.     

Direct and indirect predictions of enteric methane daily production,yield, and intensity per unit of milk and cheese,from fatty acids and milk Fourier-transform infrared spectra

Mitigating the dairy chain's contribution to climate change requires cheap, rapid methods of predicting enteric CH₄ emissions (EME) of dairy cows in the field. Such methods may also be useful for genetically improving cows to reduce EME. Our objective was to evaluate different procedures for predicting EME traits from infrared spectra of milk samples taken at routine milk recording of cows. As a reference method, we used EME traits estimated from published equations developed from a meta-analysis of data from respiration chambers through analysis of various fatty acids in milk fat by gas chromatography (FA_GC). We analyzed individual milk samples of 1,150 Brown Swiss cows from 85 farms operating different dairy systems (from very traditional to modern), and obtained the cheese yields of individual model cheeses from these samples. We also obtained Fourier-transform infrared absorbance spectra on 1,060 wavelengths (5,000 to 930 waves/cm) from the same samples. Five reference enteric CH₄ traits were calculated: CH₄ yield (CH₄/DMI, g/kg) per unit of dry matter intake (DMI), and CH₄ intensity (CH₄/CM, g/kg) per unit of corrected milk (CM) from the FA_GC profiles; CH₄ intensity per unit of fresh cheese (CH₄/CY_CURD, g/kg) and cheese solids (CH₄/CY_SOLIDS, g/kg) from individual cheese yields (CY); and daily CH₄ production (dCH₄, g/d). Direct infrared (IR) calibrations were obtained by BayesB modeling; the determination coefficients of cross-validation varied from 0.36 for dCH₄ to 0.57 for CH₄/CM, and were similar to the coefficient of determination values of the equations based on FA_GC used as the reference method (0.47 for CH₄/DMI and 0.54 for CH₄/CM). The models allowed us to select the most informative wavelengths for each EME trait and to infer the milk chemical features underlying the predictions. Aside from the 5 direct infrared prediction calibrations, we tested another 8 indirect prediction models. Using IR-predicted informative fatty acids (FA_IR) instead of FA_GC, we were able to obtain indirect predictions with about the same precision (correlation with reference values) as direct IR predictions of CH₄/DMI (0.78 vs. 0.76, respectively) and CH₄/CM (0.82 vs. 0.83). The indirect EME predictions based on IR-predicted CY were less precise than the direct IR predictions of both CH₄/CY_CURD (0.67 vs. 0.81) and CH₄/CY_SOLIDS (0.62 vs. 0.78). Four indirect dCH₄ predictions were obtained by multiplying the measured or IR-predicted daily CM production by the direct or indirect CH₄/CM. Combining recorded daily CM and predicted CH₄/CM greatly increased precision over direct dCH₄ predictions (0.96–0.96 vs. 0.68). The estimates obtained from the majority of direct and indirect IR-based prediction models exhibited herd and individual cow variability and effects of the main sources of variation (dairy system, parity, days in milk) similar to the reference data. Some rapid, cheap, direct and indirect IR prediction models appear to be useful for monitoring EME in the field and possibly for genetic/genomic selection, but future studies directly measuring CH₄ with different breeds and dairy systems are needed to validate our findings.     

Saccharomyces cerevisiae: a potential stereospecific reduction tool for biotransformation of mono- and sesquiterpenoids

Terpenes and terpenoids are among the key impact substances in the food and fragrance industries. Equipped with pharmacological properties and applications as ideal precursors for the biotechnological production of natural aroma chemicals, interests in these compounds have been escalating. Hence, the syntheses of new derivatives that can show improved properties are often called for. Stereoselective biotransformation offers several benefits to increase the rate of production, in terms of both the percentage yield and its enantiomeric excesses. Baker's yeast (Saccharomyces cerevisiae) is broadly used as a whole cell stereospecific reduction biocatalyst, due to its capability in reducing carbonyls and carbon-carbon double bonds, which also extends its functionality as a versatile biocatalyst in terpenoid biotransformation. This review provides some insights on the development and prospects in the reductive biotransformation of monoterpenoids and sesquiterpenoids using S. cerevisiae, with an overview of strategies to overcome the common challenges in large-scale implementation.     

The applications of conventional and innovative mechanical technologies to tailor structural and functional features of dietary fibers from plant wastes: A review

Plant food wastes generated through the food chain have attracted increasing attention over the last few years not only due to critical environmental and economic issues but also as an available source of valuable components such as dietary fibers. However, the exploitation of plant waste remains limited due to the lack of appropriate processing technologies to recover and tailor fiber functionalities. Among the different technologies developed for waste valorization, mechanical techniques were suggested to be a promising and sustainable strategy to extract fibers with improved functionalities. In this context, the present review describes different mechanical technologies (conventional and innovative) with potential applications to produce micro/nanofibers from various plant residues, highlighting the operating principle as well as the main advantages and pitfalls. The impact on the structural, technological, and functional properties of fibrous materials is comprehensively discussed. The extent of fiber modification not only highly depended on the technology and operation conditions used but also on fiber composition and the application of posttreatments such as dehydration. Other variables, including economic and environmental issues such as equipment cost, energy demand, and eco-friendly features, are also reviewed. The outputs of this review can be used by both the industrial sector and academia to select a suitable combination of fiber and processing technology for designing novel foods with improved functionalities that fulfill market trends and consumer needs.     

Invited review: Authentication of milk by direct and indirect analysis of triacylglycerol molecular species

Milk, milk-based products, and milk derivatives represent an important group of food commodities, with high nutritional value and widely consumed by large segment of consumers, including pregnant women, newborns, children, and the elderly. Food authentication is a rapidly growing field because of increasing consumer awareness regarding food quality and safety. This review attempts to critically summarize the status of direct and indirect analysis of the molecular species of triacylglycerols (TAG) used to assess the authenticity of milk. Identification and quantification of TAG molecular species in milk fat can be accurately performed even though analytical approaches focused on fraud evaluation should be developed. Recent analytical breakthroughs and novel techniques are discussed, along with their applications in milk authentication.     

Formation and potential uses of milk proteins as nano delivery vehicles for nutraceuticals: A review

The aim of this review was to highlight the progress achieved in the use of milk protein as nano vehicles for nutraceuticals. Reassembled casein and β‐casein micelles and core/shell nanoparticles from casein with other biopolymers have been prepared. Also, cross‐linking of casein micelles has developed stable nanoparticles. Nanogels of whey proteins (WP), β‐lactoglobulin (β‐LG) and lactoferrin (Lf) have been prepared by controlled thermal treatment, and several core/shell nanoparticles have been developed from WP or β‐LG with several polysaccharides. The developed caseins and WP nanoparticles have been used as carriers for several nutraceuticals. Examples have been presented and discussed.