This study investigated the effects of addition of beta-glucan from 2 different cereal sources (oat and barley) on growth and metabolic activity of Bifidobacterium animalis ssp. lactis (Bb-12) as determined by plating on a selective medium in yogurt during prolonged cold storage. These yogurt batches were compared to unsupplemented and inulin supplemented controls. All batches were also assessed for syneresis. Oat beta-glucan addition resulted in improved probiotic viability and stability comparable to that of inulin. It also enhanced lactic and propionic acid production. The barley beta-glucan addition suppressed proteolytic activity more than that from oat. These improvements were hindered by greater syneresis caused likely by thermodynamic incompatibility. Small amplitude oscillatory measurements of acidified model mixture of beta-glucan/skim milk solids showed formation of casein gel within the beta-glucan network. Binary mixtures of beta-glucan and skim milk solids had apparent pseudoplastic and non-Newtonian behavior governed mainly by beta-glucan contribution. Above critical concentrations, the mixtures underwent phase separation with the lower phase rich in protein. The phase diagram also showed that the addition of beta-glucan may be possible at or below 0.24 w/w%.

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This study investigated the effect of replacing shortenings at 20, 30 and 40% levels with two b-glucan concentrates (BGC) prepared from barley and oat on rheological and physical properties of cake batter, and the quality of the resultant cakes as determined by the volume index, texture profile, color of crust, and crumb and staling at three conditions of storage. The consistency, flow behavior indices, storage and loss moduli of batter, increased as the level of BGCs increased. Addition of BGC decreased the volume and increased hardness. The crust color of cake became lighter and crumb color became darker. Staling, as measured by the development of hardness, increased as a function of storage time and the source and the level of BGC at three storage temperatures. Minimum staling was noticed under frozen storage. Cake containing 20% barley BGC was of similar quality as a cake containing full fat. PRACTICAL APPLICATIONSThe study is of relevance to the baking industry, which is endeavoring to develop products that contain low fat and offer superior nutritional quality. b-Glucan, a known dietary fiber, offers several health benefits and can be used for replacing fat due to its high water-binding and viscosity-enhancing properties. Cereal-based products are ideal for delivering dietary fiber. This study provides information on how fat substitution by b-glucan concentrates affects the properties of cake batter and the cake quality. Data reported on the consistency and viscoelastic properties of batter are important in the development of new products.

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The use of live probiotic bacteria as food supplement has become popular. Capability of probiotic bacteria to be kept at room temperature becomes necessary for customer's convenience and manufacturer's cost reduction. Hence, production of dried form of probiotic bacteria is important. Two common drying methods commonly used for microencapsulation are freeze drying and spray drying. In spite of their benefits, both methods have adverse effects on cell membrane integrity and protein structures resulting in decrease in bacterial viability. Microencapsulation of probiotic bacteria has been a promising technology to ensure bacterial stability during the drying process and to preserve their viability during storage without significantly losing their functional properties such acid tolerance, bile tolerance, surface hydrophobicity, and enzyme activities. Storage at room temperatures instead of freezing or low temperature storage is preferable for minimizing costs of handling, transportation, and storage. Concepts of water activity and glass transition become important in terms of determination of bacterial survival during the storage. The effectiveness of microencapsulation is also affected by microcapsule materials. Carbohydrate- and protein-based microencapsulants and their combination are discussed in terms of their protecting effect on probiotic bacteria during dehydration, during exposure to harsh gastrointestinal transit and small intestine transit and during storage.

A series of thiosemicarbazones and semicarbazone derivatives of (±)‐3‐menthone have been synthesized and their anti‐HIV activity evaluated against HIV‐1(IIIB)and HIV‐2 (ROD). The studies revealed that maximum protection is offered by chloro‐substituted derivatives 2 and 7 against HIV‐1 (IIIB) and HIV‐2 (ROD).

Angiotensin-converting enzyme inhibitory (ACE-I) activity as affected by Lactobacillus helveticus strains (881315, 881188, 880474, and 880953), and supplementation with a proteolytic enzyme was studied. Reconstituted skim milk (12% RSM) or whey protein concentrate (4% WPC), with and without Flavourzyme(®) (0.14% w/w), were fermented with 4 different L. helveticus strains at 37 °C for 0, 4, 8, and 12 h. Proteolytic and in vitro ACE-I activities, and growth were significantly affected (P < 0.05) by strains, media, and with enzyme supplementation. RSM supported higher growth and produced higher proteolysis and ACE-I compared to WPC without enzyme supplementation. The strains L. helveticus 881315 and 881188 were able to increase ACE-I to >80% after 8 h of fermentation when combined with Flavourzyme(®) in RSM compared to the same strains without enzyme supplementation. Supplementation of media by Flavourzyme(®) was beneficial in increasing ACE-I peptides in both media. The best media to release more ACE-I peptides was RSM with enzyme supplementation. The L. helveticus 881315 outperformed all strains as indicated by highest proteolytic and ACE-I activities.