LIQUID–SOLID EXTRACTION OF SOLUBLE SOLIDS AND TOTAL PHENOLIC COMPOUNDS OF CAROB BEAN (Ceratonia siliqua L.)

Total mass transfer coefficients of soluble solids (SS) and total phenolic compounds (TPC) were determined during carob extraction. The Arrhenius equation was applied to determine the efficiency of process temperature, as an alternative approach to Fick's second law. Carob pod, cut into small pieces (internal diameter: 5–7 mm), was contacted with water in batch system to extract SS by continuous circulation of water at different temperatures (20, 50 and 85C). The process was also performed at 85C using an industrial‐scale extractor. Activation energies for both SS and TPC diffusions were calculated as 5.84 and 0.072 × 10^?3 kJ/mol, respectively. As expected, higher extract concentrations were achieved with higher temperatures. In contrast, high extraction temperature, even at 85C, did not cause hydroxymethylfurfural (HMF) formation. As the increase in temperature does not affect formation of HMF during carob pod extraction, higher operational temperatures such as 80–90C may be applied to obtain higher solute concentrations.     

KINETIC MODELING OF ANAEROBIC THERMAL DEGRADATION OF ASCORBIC ACID IN ROSE HIP (ROSA CANINA L) PULP

Ascorbic acid loss in thermally treated rose hip pulp was modeled mathematically. Isothermal experiments in the temperature range of 70–95C were utilized to determine the kinetics of ascorbic acid loss in the pulp during heating under anaerobic circumstances. Changes in ascorbic acid decomposition followed a first‐order reaction. Temperature dependence of the rate constant during thermal processing of rose hip pulp obeyed the Arrhenius relationship with an activation energy of 47.5 kJ/mole.     

A new approach for solution of vehicle routing problem with hard time window: an application in a supermarket chain

In this study, a vehicle routing problem with hard time windows (VRPHTW) that appears to meet demands of customers’ service within time intervals in a supermarket chain is solved. In VRPHTW, to reach a solution by an exact method is quite difficult and sometimes impossible if number of constraints is large enough (i.e., NP-hard), and solution time of a VRPHTW grows exponentially. As the size of the problem grows, a near optimal solution can be found using a heuristic method. A hierarchical approach consisting of two stages as “cluster-first route-second” is proposed. In the first stage, customers are assigned to vehicles using three different clustering algorithms (i.e., K-means, K-medoids and DBSCAN). In the second stage, a VRPHTW is solved using a MILP. The main contribution of the article is that the proposed hierarchical approach enables us to deal with a large size real problem and to solve it in a short time using the exact method. Finally, the proposed approach is employed on a supermarket chain. An instance of the algorithm is demonstrated to illustrate the applicability of the proposed approach and the results obtained are highly favourable.     

MICROBIOLOGICAL, PHYSICO-CHEMICAL AND TOXICOLOGICAL QUALITY OF TRADITIONAL TURKISH CHEESE DESSERTS

ABSTRACT

A total of 100 fresh‐cheese‐based desserts (Hosmerim and Cheese helva) from nine different production areas in Marmara Region of Turkey were studied. There were no statistically significant differences in microbiological composition between Hosmerim and Cheese helva. Mean values of APC, Staphylococcus aureus, molds, yeasts, osmophilic yeasts for Hosmerim were 5.7 × 10⁴, 8.0 × 10², 1.8 × 10³, 2.8 × 10³, 1.6 × 10³ cfu/g, respectively, while coliform bacteria, Escherichia coli and Bacillus cereus were <10 cfu/g. Results for Cheese helva were slightly higher. Salmonella spp. and staphylococcal enterotoxin were not detected in 25 g of any sample. Cheese helva, however, had a significantly lower pH and significantly higher contents of protein, fat and carbohydrates, and thus, also a higher content of dry matter. Within each product category, a large variation was observed for both microbiological counts as well as for the chemical composition. This indicates a lack of standardization in the manufacturing process and prompts for the establishment of appropriate process control measures.

PRACTICAL APPLICATIONS

The aim of this study was to determine the chemical and hygienic quality traits of traditional cheese desserts, namely Cheese helva and Hosmerim. For this purpose, 50 Cheese helva and 50 Hosmerim samples obtained from different regions in Turkey were analyzed on account of their microbiological, physico‐chemical and toxicological properties. The presence of some pathogens in the samples and the variable chemical composition indicate that the production process should be defined in “Codes of Good Manufacturing Practice” and the product characteristics should be codified in order to achieve a product with a defined level of microbiological safety.     

An overview of the Turkish dairy sector

The livestock sector and dairy subsector have great importance for Turkey, in terms of both nutrition and economy. The share of the livestock sector in the total agricultural production value has varied between 25% and 30% in the last three decades. Raw milk production is characterized by small-scale farms, with an average of three heads of dairy cattle per farm. Turkey's dairy industry was established and developed by the State with the opening of the Turkish Dairy Industry Institution (TSEK) in 1963 as a state-owned enterprise (SOE). TSEK facilitated modernization of the sector, created a dairy market and played a role in stabilizing the consumer and producer prices. In 1995, a liberalization movement in the agricultural sector started in Turkey and the TSEK enterprises were privatized. After privatization, producer prices decreased between 11.51% and 18.45% and consumer prices of dairy products increased in general. Today, the dairy processing sector has a dual structure that on one hand comprises many small- and medium-sized enterprises, while on the other features seven large holding companies that hold the largest market share (CR4 71). This study aims to show that the restructuring of the agricultural SOEs in the first place resulted in undesirable impacts, and thus that the planning and implementation of the privatization of the state enterprises in the dairy sector should be taken as a strategy in the medium term, using the experiences of other developing countries.