Ice cream is a dairy product with good potential to act as a food carrier for probiotic bacteria. The incorporation of probiotic bacteria into ice cream is highly advantageous since, in addition to making a functional healthy food, ice cream in itself contains beneficial substances such as dairy raw materials, vitamins and minerals, and is consumed by the general population. Also, compared with fermented milks as a vehicle, ice cream supports considerably greater viability of probiotic strains during production and especially storage. However, losses in the viability of probiotic bacteria in ice cream unavoidably occur during product formulation, processing, storage and melting. During these stages, probiotic cells are subjected to different stresses related to pH, acidity, redox potential, freezing, oxygen (especially in overrun processing), sugar concentration and osmotic effects, hydrogen peroxide, antagonistic impact of co-cultures (in fermented ice creams), and mechanical shearing. It seems that the rate of loss of probiotic cells is greater during the freezing process than during storage. Practicing methods such as selection and application of oxygen-resistant probiotic strains, elimination of molecular oxygen (using oxygenscavenging components, packaging material that is impermeable to oxygen as well as thicker packaging materials and active packaging systems), applying severe heat treatment, using microencapsulation techniques, and adjusting the product formulation (e.g., fortification of milk with nutrients and prebiotics) can increase the viability of probiotics in the final product. Supplementation of ice cream with probiotic bacteria has been found to have little effect on its flavor, texture or other sensory characteristics. There are also many ways to improve the sensory attributes of the product to compensate for any changes that do occur. This article reviews the viability of probiotic bacteria in ice cream and the main methods used to improve their viability and the sensory characteristics of probiotic ice cream.

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Tea is an agricultural product of the leaves, leaf buds, and internodes of various cultivars and sub-varieties of the Camellia sinensis plant, processed and vulcanized using various methods. Tea is a main beverage in Iranian food basket so should be free from toxic elements such as pesticides residue. There is no data bank on the residue of pesticides in the consumed black tea in Iran. The present study is the first attempt for monitoring of 25 pesticide residues from different chemical groups in tea samples obtained from local markets in Tehran, I.R. Iran during the period 2011. A reliable and accurate method based on spiked calibration curve and QuEChERS sample preparation was developed for determination of pesticide residues in tea by gas chromatography–mass spectrometry (GC/MS). The using of spiked calibration standards for constructing the calibration curve substantially reduced adverse matrix-related effects and negative recovery affected by GCB on pesticides. The recovery of pesticides at 3 concentration levels (n = 3) was in range of 81.4 - 99.4%. The method was proved to be repeatable with RSDr lower than 20%. The limits of quantification for all pesticides were ≤20 ng/g. 53 samples from 17 imported and manufactured brand were analyzed. Detectable pesticides residues were found in 28.3% (15 samples) of the samples. All of the positive samples were contaminated with unregulated pesticides (Endosulfan Sulfate or Bifenthrin) which are established by ISIRI. None of the samples had contamination higher than maximum residue limit set by EU and India.

Zearalenone (Zen) is a mycotoxin with estrogenic effect which contaminates cereals. In cell culture, Zen and its metabolite, α-Zearalenol (α-Zel), stimulate breast cancer cells growth. Today hormone-dependent cancers are important because of high incidence and death rate. Previous studies showed that Zen and α-Zel have an effect on hormone-dependent cancers. This study explains the effects of the mentioned compounds in comparison with Raloxifene as an anti-estrogen. Cell culture technique was used with MDA-MB-231 and T47D cells for evaluation of compounds. MDA-MB-231 cells were used as negative control and also for proving that treatment compounds merely affect, due to their proliferation activity in the applied doses. According to the Resazurine-based method, for toxicity assay, none of the test compounds have an effect on MDA-MB-231 cells but do effect the growth of T47D cells. Zen and α-Zel at low concentrations (10–8–10–9 M) stimulated T47D cell growth and Raloxifene strongly inhibited cell growth induced by Zen and α-Zel. There is a noticeable result in controlling diet of hormonal carcinogenic compounds and applying novel anti-estrogens for prevention and treatment of hormone-dependent cancers.