Computational shelf-life dating : complex systems approaches to food quality and safety

Shelf-life is defined as the time that a product is acceptable and meets the consumers expectations regarding food quality. It is the result of the conjunction of all services in production, distribution, and consumption. Shelf-life dating is one of the most difficult tasks in food engineering. Market pressure has lead to the implementation of shelf-life by sensory analyses, which may not reflect the full quality spectra. Moreover, traditional methods for shelf-life dating and small-scale distribution chain tests cannot reproduce in a laboratory the real conditions of storage, distribution, and consumption on food quality. Today, food engineers are facing the challenges to monitor, diagnose, and control the quality and safety of food products. The advent of nanotechnology, multivariate sensors, information systems, and complex systems will revolutionize the way we manage, distribute, and consume foods. The informed consumer demands foods, under the legal standards, at low cost, high standards of nutritional, sensory, and health benefits. To accommodate the new paradigms, we herein present a critical review of shelf-life dating approaches with special emphasis in computational systems and future trends on complex systems methodologies applied to the prediction of food quality and safety.Fundo Europeu de Desenvolvimento Regional (FEDER) - Programa POS-ConhecimentoFundação para a Ciência e a Tecnologia (FCT) - SFRH/BPD/26133/2005, SFRH/ BPD/20735/200

Application of anthocyanins from blackcurrant (Ribes nigrum L.) fruit waste as renewable hair dyes

There is much concern about the toxicological effects of synthetic hair dyes. As an alternative approach, renewable waste blackcurrant (Ribes nigrum L.) fruit skins from the fruit pressing industry were extracted using acidified water with a solid-phase purification stage. Anthocyanins colorants were isolated in good yields (2-3% w/w) and characterized by HPLC. Sorption of anthocyanins onto hair followed a Freundlich isotherm; anthocyanin-anthocyanin aggregation interactions enabling high build-up on the substrate. Sorption energy of cyanidin-3-O-glucoside (monosaccharide) > cyanidin-3-O-rutinoside (disaccharide), but sorption properties of different anthocyanin glucosides were very similar. Intense blue-colored dyeings on hair could be achieved with λmax-vis at 580 nm, typical of the anionic quinonoid base – it is suggested that the hair provides an environment that enables the stabilization of the anionic quinonoid base on adsorption through association with cations in the hair and copigmentation effects. Dyeings were stable to multiple washes

A nontoxic polypeptide oligomer with a fungicide potency under agricultural conditions which is equal or greater than that of their chemical counterparts

Research ArticleThere are literally hundreds of polypeptides described in the literature which exhibit fungicide activity. Tens of them have had attempted protection by patent applications but none, as far as we are aware, have found application under real agricultural conditions. The reasons behind may be multiple where the sensitivity to the Sun UV radiation can come in first place. Here we describe a multifunctional glyco-oligomer with 210 kDa which is mainly composed by a 20 kDa polypeptide termed Blad that has been previously shown to be a stable intermediary product of β-conglutin catabolism. This oligomer accumulates exclusively in the cotyledons of Lupinus species, between days 4 and 12 after the onset of germination. Blad-oligomer reveals a plethora of biochemical properties, like lectin and catalytic activities, which are not unusual per si, but are remarkable when found to coexist in the same protein molecule. With this vast range of chemical characteristics, antifungal activity arises almost as a natural consequence. The biological significance and potential technological applications of Blad-oligomer as a plant fungicide to agriculture, its uniqueness stems from being of polypeptidic in nature, and with efficacies which are either equal or greater than the top fungicides currently in the market are addressedinfo:eu-repo/semantics/publishedVersio

Aspects of the biochemistry of the thermophilic microorganism Bacillus stearothermophilus.

Thermophilic microorganisms present two fundamental proolems. (I) How are they able to grow at temperatures greatly above those normally considered suitable for life. (2) Why do thermophiles not grow at more moderate temperatures. This thesis is an account of experiments directed towards resolution of these problems using a prototrophic strain of the thermophile Bacillus stearothermophilus. Although virtually all the thermophile enzymes isolated to date have proved to be thermostable compared with their mesophile counterparts the possibility has remained open that part of the mechanism of thermophily is a rapid resynthesis of denatured proteins. It is shown here that protein turnover does occur during growth out the rate is too low to be compatible with this ''rapid repair" hypothesis. Studies of the stabilities of individual enzymes in intact cells confirm the results of the turnover experiments. This organisms' ability to grow on minimal media facilitated an examination of the energetics of growth. The energy required for growth is shown to be comparable with that of related mesophiles with no evidence for a massive diversion of energy for resynthesis of denatured macromolecules. These growth yield studies also show that the efficiency of substrate utilization decreases as the temperature rises. This is largely the result of changes in the extent of oxidation of the substrate. The effects of temperature on the regulation of a key enzyme, isolated from the thermophile, pyruvate kinase, have been studied to test the hypothesis that the temperature limits for growth of a particular microorganism are the result of an accumulation of derangements of metabolic regulation at temperature extremes. In most respects except thermostability the thermophile enzyme resembles those from mesophiles. Temperature effects on kinetic and regulatory parameters are too small to be implicated in the lower limit for growth but are probably involved in the temperature effects on growth yield