One option for the management of wastewater from tofu production: Freeze concentration in a falling-film system

Tofu whey is a liquid by-product from tofu production. Although it contains oligosaccharides, proteins and isoflavones, which could be isolated and used as ingredients for functional products, it is currently not utilized but disposed as a waste stream. However, when disposed directly to the environment tofu whey can cause bad odours and pollution of the surface and ground water, so that treatment is necessary. The wastewater treatment of industrial tofu production by current technologies is problematic, because of the high expenses and the lack of knowledge about their efficient operation. Hence the need to use alternative technologies such as freeze concentrations. Falling-film freeze concentration tests of tofu whey were carried out on pilot-scale equipment in three stages. The increase in soluble solids content of the tofu whey and the amount and purity of the ice formed were analysed. It was observed that the concentration could be increased by a factor of 8 (from an initial concentration of 1.9°Brix to a final concentration of 15.5°Brix). The electrical conductivity of the tofu whey at the last stage was 6.48 mS/cm and the pH was 5.22. The process efficiency was 82.9% at the first stage but dropped to lower values at later stages. Falling film freeze concentration is a promising alternative to recover the solutes retained in the effluent from the tofu industry, reducing its volume and improving environmental management.     

Peptide enriched functional food adjunct from soy whey: A statistical optimization study

Soy whey is generated as a process waste while preparing soy based food products tofu, causing environmental pollution and also representing an economic penalty against the industrial process. Therefore, its valorization is of prime importance to the industry. The present investigation aims to convert this proteinaceous waste into bioactive peptide enriched hydrolysate. Soy whey protein was enzymatically treated with the Aspergillus awamori nakazawa protease. Respective protease was efficient to produce antioxidant peptide beholding radical scavenging ability of 40–50% at normal conditions. Remarkable increase in the radical scavenging activity upto 70% was noticed at the response surface methodology (RSM) based optimized condition: temperature 40°C, salt concentration (NaCl) 0.05 M, surfactant concentration (Triton-X 100) 0.0075%, hydrolysis time 80 min, and enzyme to substrate concentration 164 IU/g of soy whey protein. The present study emphasizes the biotransformation of proteineceous waste into antioxidant peptide rich soy whey protein hydrolysate to be considered as additives for food preparation and formulation.     

Whey—pollution problem and potential utilization

The high biochemical oxygen demand (BOD₅) of whey poses a major world-wide disposal and pollution problem for the dairy industry, for which an effective and permanent solution is urgently needed. Biological waste water treatment technologies can assist in the safe disposal of whey or whey permeate within the federal environment specifications, but only at substantial cost. One alternative is use of whey, or whey permeate rich in lactose and protein, in processes in which saleable products contribute wholly or partially to the costs. Production of whey proteins by ultrafiltration, lactose hydrolysis products, and the use of whole whey or whey permeate as a fermentation feedstock are possible options. The present situation is discussed, together with projections for commercial potential, limitations of the biotechnology of whey processing, the end products and nutritional aspects.     

乳清蛋白水解制备功能性多肽的研究概况

乳清是生产干酪及干酪素过程中获得的大量液态副产物,含有丰富的营养成分,其主要成分乳清蛋白的营养价值极高。随着近年来小肽生物活性功能研究的开展,对于乳清蛋白水解物中功能性多肽的研究成为主要方向。近年来的研究中发现乳清蛋白中含有多种生物活性肽,包括ACE抑制肽、抑菌肽、抗病毒肽、抗氧化活性肽及其它活性肽。目前,国内外有关ACE抑制肽的研究较多,而对降胆固醇肽的研究多是以大豆蛋白为原料,而更具有研究价值的乳清蛋白源降胆固醇肽研究较少。本人以乳清蛋白为原料,对其酶解产物的降胆固醇活性肽进行分离制备,既充分利用了干酪的副产物,减少了资源浪费和环境污染,又能提供一种新型降胆固醇功能产品,为商业化开发乳清蛋白降胆固醇功能产品提供理论依据。本文结合本人对降胆固醇肽的研究,综述了乳清蛋白源功能性多肽的制备、分离纯化技术及其活性多肽的研究概况。     

Nondairy food applications of whey and milk permeates: Direct and indirect uses

Permeates are generated in the dairy industry as byproducts from the production of high-protein products (e.g., whey or milk protein isolates and concentrates). Traditionally, permeate was disposed of as waste or used in animal feed, but with the recent move toward a “zero waste” economy, these streams are being recognized for their potential use as ingredients, or as raw materials for the production of value-added products. Permeates can be added directly into foods such as baked goods, meats, and soups, for use as sucrose or sodium replacers, or can be used in the production of prebiotic drinks or sports beverages. In-direct applications generally utilize the lactose present in permeate for the production of higher value lactose derivatives, such as lactic acid, or prebiotic carbohydrates such as lactulose. However, the impurities present, short shelf life, and difficulty handling these streams can present challenges for manufacturers and hinder the efficiency of downstream processes, especially compared to pure lactose solutions. In addition, the majority of these applications are still in the research stage and the economic feasibility of each application still needs to be investigated. This review will discuss the wide variety of nondairy, food-based applications of milk and whey permeates, with particular focus on the advantages and disadvantages associated with each application and the suitability of different permeate types (i.e., milk, acid, or sweet whey).     

Production of Bioingredients from Kluyveromyces marxianus Grown on Whey: An Alternative

Whey waste is a major problem for the dairy industry. Finding alternative means to reduce its pollution potential and produce high value-added bioingredients has been attempted by many researchers. Kluyveromyces marxianus var. marxianus is a dairy yeast that produces β-galactosidase, allowing for whey fermentation. Also, K. marxianus has been proposed as a source of: (1) oligonucleotides, used as flavor enhancers in food products; (2) oligosaccharides, used as prebiotics to stimulate the growth of Bifidobacterium sp. in the animal and human intestines; and (3) oligopeptides, immunostimulators added to dairy products that are released in the wort after whey protein proteolysis. Fed-batch fermentation can be used as an alternative process to avoid increases in lactose concentration and prevent the catabolite repression of the respiratory enzyme synthesis during aerobic fermentation, thus allowing for high biomass yields. The relevance of these factors on yeast fermentation of whey is summarized in this critical review.     

Developments in membrane technology

Reverse osmosis and ultrafiltration of whey are commercially successful techniques for adding value to whey. Advances in membrane performance and plant configuration have improved the efficiency of reverse osmosis for whey concentration to a level significantly greater than that of conventional evaporation. Ultrafiltration of whey k also well proven and can provide a range of protein products of diverse composition and functionality.     

乳清蛋白的市场与应用

<正> 一、美国乳业及乳清粉行业近况 1.美国乳业近况在过去的二十年中,美国奶牛的存栏量总体呈下降趋势,但牛奶产量却稳步攀升,在2008年达到了860亿升。牛奶单产的不断提升得益于基因技术的不断进步、动物营养的不断改善以及养殖操作技术的不断改进。今年,美国奶牛的存栏量及牛奶的产量与2008年相比有所下降,这主要是由国内外市场的需求减少所造成的。在经济危机的影响下,美国奶牛养殖的损失较为严重,奶农纷纷减少了奶牛养殖数量。未来,美国经济的复苏直接     

Integrated sustainable process design framework for cassava biobased packaging materials: Critical review of current challenges,emerging trends and prospects

BackgroundCassava represents a reasonable share in biobased material development globally. The production of its biopolymer derivatives using conventional techniques/methods is accompanied by significant wastes with potential negative environmental impact. Among the biopolymer derivatives, starch dominates as lone additive in cast matrices with packaging limitations, requiring other biopolymer derivatives, and/or external-source modifiers for matrix improvement. Exploiting integrated sustainable engineering process design of all biopolymer derivatives, is a novel approach in designing efficient system of cassava biobased materials for food and non-food applications.Scope and approachA critical review on the current and emerging techniques and methodologies to address cassava wastes and challenges of cassava research for application on biobased packaging are provided. The potential of integrated sustainable engineering process design framework for packaging system is discussed, and prospects for improvement suggested.Key findings and conclusionsChallenges of significant waste generated during conventional processing and on the application process aiming at tailoring materials to industrial needs are reported. These materials should be improved using a holistic approach reflecting the target products, variable environment, minimising production costs and energy. Use of novel material resources, eliminating waste, and employing a standardised methodology via desirability optimisation, present a promising process integration tool for development of sustainable cassava biobased systems.     

Water utilisation,energy utilisation and waste water management in the dairy industry: A review

Energy consumption, water utilisation and waste production are now important environmental issues. However, compilations of data are not readily available, making it difficult for companies to assess how they are performing. This review aims to summarise the data that are available, including some benchmarking values. Also discussed are techniques for reducing water and energy consumption and waste production, tools for monitoring this and assistance that is available to improve efficiency ratios and reduce costs associated with these issues. Using information in this review, an individual company should be able to compare its performance against others producing similar products, nationally or globally in order to set and maintain rational benchmarking values to improve its performance and deal with environmental concerns.     

乳清产品在冰淇淋和冷冻乳制品甜食中的应用

<正> 乳清和乳清蛋白产品在过去的60多年中已经被成功应用于冰淇淋和其他冷冻乳制品甜食中。甜乳清、乳清浓缩蛋白(蛋白质含量34～89%)和乳清分离蛋白(蛋白质含量≥90%)是最常用的乳清产品。其他的乳清配料,如脱乳糖乳清和脱盐乳清也是常用的配料。成本优势和提升产品质量是使用乳清产品的主要出发点,     

大豆制品生产废水综合开发研究进展

豆制品生产中产生大量的有机废水,这些废水中含有多种多样的营养物质,直接排放不仅污染环境而且浪费资源。文章阐述了从大豆制品生产废水中提取功能性物质如大豆低聚糖、大豆乳清蛋白、大豆异黄酮、大豆皂苷、大豆多糖等的研究进展,为豆制品废水的综合利用提供理论依据和实践基础。     

Izumoring: a novel and complete strategy for bioproduction of rare sugars

Starch, whey or hemicellulosic waste can be used as a raw material for the industrial production of rare sugars. D-glucose from starch, whey and hemicellulose, D-galactose from whey, and D-xylose from hemicellulose are the main starting monosaccharides for production of rare sugars. We can produce all monosaccharides; tetroses, pentoses and hexoses, from these raw materials. This is achieved by using D-tagatose 3-epimerase, aldose isomerase, aldose reductase, and oxidoreductase enzymes or whole cells as biocatalysts. Bioproduction strategies for all rare sugars are illustrated using ring form structures given the name Izumoring.     

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.     

Minor and trace element content of two typical Italian sheep dairy products

The concentration ranges in milk and cheese of a number of metallic elements relevant to the health of the consumer are dependent upon animal species, feeding, time of year, environmental conditions and manufacturing processes. We have measured the concentrations of selected trace elements--Al, Ba, Cd, Co, Cr, Cu, Fe, Mg, Mn, Ni, Pb, Pt, Sr and Zn--in raw ewes' milk and typical ewes' milk cheeses. Samples of milk, curd, whey, cheese after moulding, cheese after salting, commercial cheese (Pecorino), Ricotta, scotta and brine were analyzed for seven complete cycles of cheese production. Samples of curd, whey, brine and waste product (i.e. scotta) were collected and analysed in addition to the cheese and milk to assess the distribution of each element in the main product, by-products and waste products during cheesemaking. Quantitative determinations were performed mainly by inductively coupled plasma atomic emission spectrometry. There were considerable differences among the trace element contents of raw ewes' milk and related products, indicating that manufacturing processes play a key role in the distribution of minor and trace elements. Two different approaches were used to assess the dietary intake of these elements associated with the consumption of Pecorino and Ricotta, and whether this had any nutritional or toxicological implications. The results indicated no toxicological risk and showed that, on the contrary, Pecorino may be a good source of several essential elements.     

Colorants in cheese manufacture: Production,chemistry, interactions,and regulation

Colored Cheddar cheeses are prepared by adding an aqueous annatto extract (norbixin) to cheese milk; however, a considerable proportion (～20%) of such colorant is transferred to whey, which can limit the end use applications of whey products. Different geographical regions have adopted various strategies for handling whey derived from colored cheeses production. For example, in the United States, whey products are treated with oxidizing agents such as hydrogen peroxide and benzoyl peroxide to obtain white and colorless spray‐dried products; however, chemical bleaching of whey is prohibited in Europe and China. Fundamental studies have focused on understanding the interactions between colorants molecules and various components of cheese. In addition, the selective delivery of colorants to the cheese curd through approaches such as encapsulated norbixin and microcapsules of bixin or use of alternative colorants, including fat‐soluble/emulsified versions of annatto or beta‐carotene, has been studied. This review provides a critical analysis of pertinent scientific and patent literature pertaining to colorant delivery in cheese and various types of colorant products on the market for cheese manufacture, and also considers interactions between colorant molecules and cheese components; various strategies for elimination of color transfer to whey during cheese manufacture are also discussed.     

Whey-ing up the options – Yesterday,today and tomorrow

Whey, first generated more than 5000 years ago, was valued in the 17th through early 19th centuries, notably as a medicinal agent against some common maladies. However, for much of history, whey has been considered a waste by-product of cheese, casein and yoghurt manufacture. Nowadays, the intrinsic value of whey components, notably the proteins, has been recognised, and a large and growing body of scientific evidence now supports the many physico-chemical, nutritional and biological properties of whey components. This evidence has established a foundation for their value as food and related ingredients. Manufacturing technologies have been, and continue to be, developed for processing whey and for isolating functional whey components in a cost-effective manner. A diverse and expanding range of whey ingredients, foods, and related products has resulted. This paper traces the history and science of whey, highlighting the quirks, struggles, accomplishments, and emerging opportunities and challenges in the field.     

Invited review: Whey proteins as antioxidants and promoters of cellular antioxidant pathways

Oxidative stress contributes to cell injury and aggravates several chronic diseases. Dietary antioxidants help the body to fight against free radicals and, therefore, avoid or reduce oxidative stress. Recently, proteins from milk whey liquid have been described as antioxidants. This review summarizes the evidence that whey products exhibit radical scavenging activity and reducing power. It examines the processing and treatment attempts to increase the antioxidant bioactivity and identifies 1 enzyme, subtilisin, which consistently produces the most potent whey fractions. The review compares whey from different milk sources and puts whey proteins in the context of other known food antioxidants. However, for efficacy, the antioxidant activity of whey proteins must not only survive processing, but also upper gut transit and arrival in the bloodstream, if whey products are to promote antioxidant levels in target organs. Studies reveal that direct cell exposure to whey samples increases intracellular antioxidants such as glutathione. However, the physiological relevance of these in vitro assays is questionable, and evidence is conflicting from dietary intervention trials, with both rats and humans, that whey products can boost cellular antioxidant biomarkers.     

大豆乳清蛋白特性及回收利用研究进展

大豆分离蛋白加工过程中产生大量乳清废水,直接排放会造成环境污染和资源浪费。大豆乳清废水中含有大豆乳清蛋白(Soybean Whey Proteins, SWP)、大豆异黄酮、大豆低聚糖等多种营养成分,其中大豆乳清蛋白应用价值极高,富含胰蛋白酶抑制剂、β-淀粉酶、大豆血球凝集素、脂肪氧合酶等多种功能因子。基于此,本文针对大豆乳清蛋白的回收利用,归纳总结了大豆乳清蛋白中的主要组成成分,并对各组分的研究利用以及其功能特性进行总结与分析,同时对大豆乳清蛋白的回收方法及利用进行了梳理,以期为工业生产实践中高值化利用提供理论和技术上的参考。     

超滤膜分离技术回收乳清蛋白工艺研究

研究利用超滤膜分离技术,从干酪素乳清废弃液中回收乳清蛋白,通过对不同超滤膜性能的比较,选择最佳的超滤膜材料、工艺流程以及运行参数,并测得分离效果。结果表明:采用PW2540型聚醚砜卷式超滤膜较好,其最佳工艺参数为操作温度35℃,操作压力0.5MPa,且超滤膜透液通量较高,运行稳定。乳清蛋白粉中蛋白质含量72.40%,灰分3.85%。经红外光谱检测证明乳清蛋白粉品质得到较大程度的提高。每吨乳清废弃液中可回收乳清蛋白粉5.13kg,具有较好的经济效益及减排环保效益。