On the Number of Synchronizing Colorings of Digraphs

We deal with k-out-regular directed multigraphs with loops (called simply digraphs). The edges of such a digraph can be colored by elements of some fixed k-element set in such a way that outgoing edges of every vertex have different colors. Such a coloring corresponds naturally to an automaton. The road coloring theorem states that every primitive digraph has a synchronizing coloring. In the present paper we study how many synchronizing colorings can exist for a digraph with n vertices. We performed an extensive experimental investigation of digraphs with small number of vertices. This was done by using our dedicated algorithm exhaustively enumerating all small digraphs. We also present a series of digraphs whose fraction of synchronizing colorings is equal to 1−1/kd, for every d≥1 and the number of vertices large enough. On the basis of our results we state several conjectures and open problems. In particular, we conjecture that 1−1/k is the smallest possible fraction of synchronizing colorings, except for a single exceptional example on 6 vertices for k=2

The effects of low-temperature potato storage and washing and soaking pre-treatments on the acrylamide content of French fries

BACKGROUND: Since the discovery in 2002 of acrylamide in a wide range of foods, there has been much work done to explore mechanisms of formation and to reduce acrylamide in commercial products. This study aimed to investigate simple measures which could be used to reduce acrylamide formation in home-cooked French fries, using potatoes from three cultivars stored under controlled conditions and sampled at three time points. RESULTS: The reducing sugar content for all three cultivars increased during storage, which led to increased acrylamide levels in the French fries. Washing and soaking (30 min or 2 h) raw French fries before cooking led to reductions in acrylamide of up to 23, 38 and 48% respectively. Pre-treated fries were lighter in colour after cooking than the corresponding controls. CONCLUSION: Pre-treatments such as soaking or washing raw French fries in water reduce acrylamide and colour formation in the final product when cooking is stopped at a texture-determined endpoint. (c) 2008 Society of Chemical Industry

Balancing environmental and economic performance in the food-processing industry

Changing customer requirements, unpredictable disturbances combined with expensive production facilities, are major problems for food processing companies to achieve synergy between the economic and environmental performance. There is notably a lack of tools to support decisions to explore effects on performance related to new product introductions, changes in production equipment, changes in planning concepts and their cross sections. We argue that interdisciplinary research that uses operations research techniques, operations management insights, food process technology and product design helps in exploring the effect of uncertainty in demand and production. As a result, process design can be more robust: both economic and environmental. This position paper explores the problem and the main elements of the proposed scenario-based simulation approach.</p

An economic and legal assessment of the EU food industry's competitiveness

The objective of this article is to assess the competitiveness of the European food industry from an economic and legal perspective. Knowledge of its present competitiveness and improvement opportunities are lacking. To close this knowledge gap, we measured the competitiveness of eight subsectors, benchmarked them with four leading world economies, assessed the effect of differences in legal requirements, and predicted future developments using scenario analysis. International economics indicators supplemented with data on legal issues from a survey conducted by leading experts were used to measure competitiveness. The results show that the EU food industry's competitiveness is weak. The legal system was positively evaluated compared to the U.S. system, but major improvements are possible. The recommendations are to improve economies of scale, economies of scope, ICT-based supply chain management, and exploit cultural differences through innovation, within a more flexible and streamlined legal framework. &lsqb;Econlit. Citations:F14, L66; Q13&rsqb;. © 2008 Wiley Periodicals, Inc.

Effects of formulation, extrusion cooking conditions, and CO 2

BACKGROUND: Acrylamide is a possible carcinogen and known to form in heat-treated carbohydrate-rich foods. This study was designed to investigate the effects of different ingredients (reducing sugars, chemical leavening agents, citric acid), processing conditions (feed moisture content: 22, 24 or 26%, exit die temperature: 110, 150 degrees C), and extrusion cooking methods (with or without CO2 injection) on acrylamide formation

Health claims in Europe: new legislation and PASSCLAIM for substantiation.

A regulation on nutrition and health claims made on foods was introduced in the European Union in 2007. This Regulation provides opportunities for the use of health claims on foods in Europe, including reduction of disease risk claims. The Regulation will be fully implemented by January 2010. A community list of permitted and rejected claims will be established and made available to the public. Some European countries have applied voluntary codes of practice on health claims for foods, awaiting the Regulation. Experience with scientific evaluation and use of health claims has been gained using these codes with regard to both generic claims that are closely related to official nutrition recommendations and to product-specific claims based on human intervention studies with the product. The European Commission supported a concerted action project, "Process for the Assessment of Scientific Support for Claims on Foods" (PASSCLAIM). This project reviewed the scientific state of the art in diet and health areas regarded most likely for health claims. The main purpose of the PASSCLAIM project was to define a set of generally applicable criteria for the scientific substantiation of health claims. These criteria were considered to be a scientifically robust tool for evaluating the quality of the data submitted in support of health claims on foods. PASSCLAIM is useful in assisting applicants for a health claim to prepare their supporting dossiers as well as in aiding agencies responsible for evaluating the scientific evidence for the claim