Phosphate and nitrite - the most commonly used additives in the meat industry

Related to a Serbian-language version of the following article: [https://vet-erinar.vet.bg.ac.rs/handle/123456789/3925

MV3: A new word based stream cipher using rapid mixing and revolving buffers

MV3 is a new word based stream cipher for encrypting long streams of data. A direct adaptation of a byte based cipher such as RC4 into a 32- or 64-bit word version will obviously need vast amounts of memory. This scaling issue necessitates a look for new components and principles, as well as mathematical analysis to justify their use. Our approach, like RC4's, is based on rapidly mixing random walks on directed graphs (that is, walks which reach a random state quickly, from any starting point). We begin with some well understood walks, and then introduce nonlinearity in their steps in order to improve security and show long term statistical correlations are negligible. To minimize the short term correlations, as well as to deter attacks using equations involving successive outputs, we provide a method for sequencing the outputs derived from the walk using three revolving buffers. The cipher is fast -- it runs at a speed of less than 5 cycles per byte on a Pentium IV processor. A word based cipher needs to output more bits per step, which exposes more correlations for attacks. Moreover we seek simplicity of construction and transparent analysis. To meet these requirements, we use a larger state and claim security corresponding to only a fraction of it. Our design is for an adequately secure word-based cipher; our very preliminary estimate puts the security close to exhaustive search for keys of size < 256 bits.Comment: 27 pages, shortened version will appear in "Topics in Cryptology - CT-RSA 2007

Small Scale Variants of the AES

Abstract. In this paper we define small scale variants of the AES. These variants inherit the design features of the AES and provide a suitable framework for comparing different cryptanalytic methods. In particular, we provide some preliminary results and insights when using off-theshelf computational algebra techniques to solve the systems of equations arising from these small scale variants.

Tight Time-Memory Trade-offs for Symmetric Encryption

Concrete security proofs give upper bounds on the attacker\u27s advantage as a function of its time/query complexity. Cryptanalysis suggests however that other resource limitations - most notably, the attacker\u27s memory - could make the achievable advantage smaller, and thus these proven bounds too pessimistic. Yet, handling memory limitations has eluded existing security proofs. This paper initiates the study of time-memory trade-offs for basic symmetric cryptography. We show that schemes like counter-mode encryption, which are affected by the Birthday Bound, become more secure (in terms of time complexity) as the attacker\u27s memory is reduced. One key step of this work is a generalization of the Switching Lemma: For adversaries with $S$ bits of memory issuing $q$ distinct queries, we prove an $n$-to-$n$ bit random function indistinguishable from a permutation as long as $S \times q \ll 2^n$. This result assumes a combinatorial conjecture, which we discuss, and implies right away trade-offs for deterministic, stateful versions of CTR and OFB encryption. We also show an unconditional time-memory trade-off for the security of randomized CTR based on a secure PRF. Via the aforementioned conjecture, we extend the result to assuming a PRP instead, assuming only one-block messages are encrypted. Our results solely rely on standard PRF/PRP security of an underlying block cipher. We frame the core of our proofs within a general framework of indistinguishability for streaming algorithms which may be of independent interest

Multi-key Security: The Even-Mansour Construction Revisited

International audienceAt ASIACRYPT 1991, Even and Mansour introduced a block cipher construction based on a single permutation. Their construction has since been lauded for its simplicity, yet also criticized for not providing the same security as other block ciphers against generic attacks. In this paper, we prove that if a small number of plaintexts are encrypted under multiple independent keys, the Even-Mansour construction surprisingly offers similar security as an ideal block cipher with the same block and key size. Note that this multi-key setting is of high practical relevance, as real-world implementations often allow frequent rekeying. We hope that the results in this paper will further encourage the use of the Even-Mansour construction, especially when a secure and efficient implementation of a key schedule would result in significant overhead

Fosfati i nitriti - najčešće korišćeni aditivi u industriji mesa

Related to an English-language version of the following article: [https://vet-erinar.vet.bg.ac.rs/handle/123456789/3926

Voda u industriji hrane - mikrobiološki osvrt

Voda se koristi na različite načine u proizvodnji hrane, čime postaje dio hrane. Voda za pranje u prehrambenoj industriji može biti izvod bakterijske kontaminacije i dodatno ugroziti kvalitet i bezbjednost hrane. Istraživanjem su obuhvaćeni uzorci vode koja se koristi u prehrambenoj industriji. Ispitivanje obuhvata 192 uzorka, od kojih je 75% iz vodovoda, a 25% iz bunara. Laboratorijsko ispitivanje vode vršeno je metodama BAS EN ISO 6222, BAS EN ISO 9308 i BAS EN ISO 7899-2. Cilj istraživanja je utvrđivanje mikrobiološkog statusa vode u prehrambenoj industriji. Istraživanjem je utvrđeno 79,69% zadovoljavajućih uzoraka i 20,31% nezadovoljavajućih uzoraka vode. U odnosu na ispitivane parametre, u 12,50% uzoraka utvrđen je povećan broj mikroorganizama na 22°C, a u 10,42% uzoraka utvrđen je povećan broj mikroorganizama na 37°C. Kada su u pitanju indikatori higijene, 8,85% nezadovoljavajućih uzoraka je bilo zbog prisustva crijevnih enterokoka, a 5,73% nezadovoljavajućih uzoraka zbog prisustva Escherichia coli i koliforma. S obzirom na prisustvo koliformnih bakterija, Escherichia coli i crijevnih enterokoka u vodi koja se koristi u prehrambenoj industriji, postoji rizik od mikrobiološke kontaminacije hrane putem vode. Ovo je posebno značajno s obzirom na udio bunarske vode u odnosu na ukupnu vodu koja se koristi u industriji hrane.Related to an English-language version of the following article: [https://vet-erinar.vet.bg.ac.rs/handle/123456789/3931

Determination of the presence of aflatoxin B1 in food and feed in Republic of Srpska (Bosnia and Herzegovina) in the period between 2014 and 2016

Aflatoxins are a mixture of related chemical compounds of bisfokuma­rine type. They are synthesized in a variety of agricultural and food products such as oilseeds, spices, cereals and other products. In the period of 2014-2016, 418 samples were analyzed for the presence of aflatoxin B1, using the ELISA method. The analysis included samples of silage (75 samples), concentrated feed (272 samples), dry fruits (16 samples), nuts (15 sam­ples), flours (5 samples) and other types of samples (35 samples). The presence of aflatoxin B1 was determined in all of the analyzed samples. The highest detected concentration of aflatoxin B1 was 4 μg/kg in the silage samples, 30 μg/kg in the concentrated feed samples, 0.40 μg/kg in samples of dried fruit, 0.81 μg/kg in nuts, 0.5 μg/kg in flour samples and 0.5 μg/kg in the other analyzed samples. Higher concentration of aflatoxin B1 from maximum residual level specified in Regulation was detected in samples of concentrated feed (2.57%)