The development and evaluation of a low-fat high-fibre muffin using Simplesse® as a fat subsitute

PhD (Nutrition), North-West University, Potchefstroom CampusBackground - The global emphasis on prevention of chronic diseases of lifestyle and known protective effects of low-fat high-fibre diets (prudent diets) motivated the development of a low-fat high-fibre baked product. Objective - The main objective was to evaluate the effects of partial and total replacement of oil by a protein-based fat substitute (Simplesse® Dry 100) in a high-fibre muffin. Setting - The experimental work and sensory analyses were done in the Food Science Laboratory, Potchefstroomse Universiteit vir Christelike Hoer Onderwys, Potchefstroom. Dietitians and consumers evaluated the muffins in Potchefstroom, Pretoria, Klerksdorp and Johannesburg. Methods - The high-fibre muffins were developed and evaluated in a step-wise programme in five sub studies, each with its own experimental design. In order to ensure that observed effects resulted from the fat substitute, the control muffins and those containing Simplesse® were also compared to muffins in which the oil was replaced by non fat milk solids. The muffins were prepared, baked and served or stored and served under controlled conditions. Sensory descriptive analyses, sensory consumer assessment, physical determinations, proximate analyses and microbial counts, were done with standardised and validated methodologies, described in detail in each chapter. Results - • A trained analytical descriptive panel indicated that Simplesse® can successfully replace up to 100% of the oil in high-fibre muffins without significant adverse effects on the sensory characteristics. • The results also showed that South African dietitians found the muffins highly acceptable, did not prefer the full-fat control, revealed a positive attitude towards all the muffin variations, and declared an intent to eat them once a week. • Similar results were obtained when consumers evaluated the muffins. • The results further indicated that the baked muffins could be stored at room temperature or frozen and thawed without remarkable adverse effects. • An important finding was that replacement of oil with Simplesse® actually improved the stability of the batter during refrigeration, suggesting that oil replacement may play a significant role in developing freshly baked convenience products from refrigerated batters. Conclusions - It is generally concluded from the results of this study that the protocol used for the evaluation of a low-fat high-fibre baked product is suitable and that non-fat milk solids (NFMS) cannot replace oil in high-fibre muffins as successfully as Simplesse®. It is further concluded that Simplesse® is a highly successful fat replacer in high-fibre muffins. The high-fibre muffins were perceived to be highly acceptable by health professionals and consumers. The analytical panel indicated only small differences between the experimental muffins and the full-fat control muffins. Differences from the control sample did not, however, necessarily imply that the muffins were unacceptable to consumers.Doctora

Live animal and carcass characteristics of South African indigenous goats

Eighty-nine intact male, castrates and female South African indigenous goats in three age groups (0, 2 - 6 and 8 permanent incisors) and two pre-slaughter conditioning groups; namely, the non-conditioned which were slaughtered within three months of purchase and the pre-slaughter conditioned, which were slaughtered 6 - 10 months after purchase or birth were used. The effect of sex, age and pre-slaughter conditioning on live animal, carcass dimensions and carcass composition were evaluated. The goats were large with live weight, carcass weight and carcass dimensions in the range of the large breeds of southern Africa. They had a high lean and low fat content. Intact males were suited for high chevon yield because they were heavy, had a high lean and low fat content, and losses during dressing and chilling were reduced by improved nutrition. Goats between 2 - 6 teeth yielded heavy carcasses that were comparable to goats in the 8-teeth group, and had proportionately more lean and less carcass fat. The hind limb was ideal for high lean and low fat, high value cuts but the dorsal trunk was bony and yielded less lean. Pre-slaughter conditioning improved the overall size of the goats and reduced the losses during slaughter and chilling. It also improved the lean/bone and lean and fat/bone indices