Processed turkey rolls were prepared with 1 or 3% whey protein concentrates WPC-50 (pH=5.80), WPC-60 (pH=4.53) and WPC-75 (pH=6.85} containing 50, 60 and 75% protein along with controls (phosphate and no phosphate). Control rolls made with 0.5% phosphate had the highest bind strength, and sensory evaluation scores. Only WPC-75 (1%) was acceptable as a binding agent and flavor enhancer. WPC-60 reduced pink discoloration of rolls, but flavor, bind and cohesiveness scores were unacceptably low. WPC-50 was not an effective binding agent. In general, rolls made with 3% WPC had lower scores for intensity of turkey flavor. Bind strength and sensory characteristics were compared for restructured beef rolls formulated with 1% salt, 0.375% sodium tripolyphosphate (STPP) or O. 07 % sodium hydroxide (NaOH), and 5, 10 or 20% added water. Controls also had 1% salt, but no STPP or NaOH. Relative bind strength of rolls was STPP > NaOH > controls. Addition of 20% water reduced bind strength. Cooked yield, moisture content, beef flavor and texture of NaOH rolls were similar to STPP rolls. Bind strength and cohesiveness of NaOH rolls were lower than STPP rolls, but still acceptable. For measuring bind strength of turkey and beef rolls, a sensitive and inexpensive penetrometer was developed. It was equipped with a top-loading balance, accessories, IBM-compatible personal computer and Quick-Basic program that allowed continuously collected penetration force data . at specific time intervals. Penetrometer bind strength and taste panel cohesiveness of turkey and beef rolls were highly correlated (r=0.89 and r=0.93, respectively).

Amino acids derived from the degradation of casein in cheese serve as precursors for the generation of key flavor compounds. Microbial degradation of tryptophan (Trp) is thought to promote formation of aromatic compounds that impart putrid fecal or unclean flavors in cheese, but pathways for their production have not been established. This study investigated tryptophan catabolism by Lactobacillus casei LC301 and LC202 and Lactobacillus helveticus CNRZ32 and LH212 cheese flavor adjuncts in carbohydrate starvation (pH 6.5, 30 or 37°C, no sugar) and cheese-like conditions (pH 5.2, 4% NaCl, 15°C, no sugar). Enzyme assays of cell-free extracts revealed both species of Lactobacillus catabolized tryptophan to indole lactic acid via indole pyruvic acid through transamination followed by dehydrogenation. Micellar electrokinetic capillary chromatography of culture supernatants showed these enzymes also catalyzed the reverse reactions, i.e., conversion of indole lactic acid to tryptophan. Tryptophan decarboxylase activity was detected in Lactobacillus cell-free extracts, but tryptamine was not detected in culture supernatants. Analysis of culture supernatants showed that tryptophan metabolism in Lactobacillus casei did not differ between the two conditions of incubation as it did in Lactobacillus helveticus LH212 and CNRZ32. Lactobacillus helveticus LH212, for example, did not catabolize Trp in carbohydrate starvation but did in cheese-like conditions. While cells of L. helveticus CNRZ32 did not catabolize Trp in either condition, they catabolized indole pyruvic acid to only Trp in carbohydrate starvation and to both Trp and indole lactic acid in cheese-like conditions. Micellar electrokinetic capillary chromatography of culture supernatants incubated under either starvation or cheese-like conditions showed Lactobacillus casei strains produced more indole lactic acid, and Lactobacillus helveticus strains favored tryptophan anabolic reactions. Based on the results obtained in this study, a putative pathway for the catabolism of tryptophan by lactobacilli in cheese is proposed.

Pediococcus acidilactici as a lactic acid producer, and sucrose were added to breakfast strip products in order to reduce added levels of sodium nitrite and sodium chloride and yet limit the growth of Clostridium botulinum and inhibit toxin production. Sucrose at 0.4 or 0.9% with P. acidilactici at 1.0 x 10 cells/g were added during preparation of breakfast strip products prepared with combinations of 40 or 80 ppm sodium nitrite and 1.0 or 2.0% sodium chloride. Other ingredients were added at levels normally used in cured meat products. C. botulinum types A and B at 1,000 spores/g were inoculated during product preparation. The finished products were sliced, vacuum packed, double bagged, vacuum sealed again, and incubated at 27 C. Samples were analyzed before incubation and every week for 4 weeks for anaerobic plate counts, pH, residual nitrite, Most Probable Number counts, and botulinal toxin. The results revealed that 0.9% sucrose increased the acid production, thus inhibiting the botulinal growth and toxin formation in the products. Lactic acid bacteria and sucrose at 0.4% did not produce enough acid to inhibit toxin formation. Sodium nitrite at 40 ppm and sodium chloride at 1.0% permitted increased growth rate and toxin development of C. botulinum. Addition of 0.9% sucrose and P. acidilactici was necessary to provide antibotulinal properties to breakfast strip products prepared with 40 ppm sodium nitrite and 1.0% sodium chloride.

Cancer is a global risk for human wellness and health. Dietary habits could profoundly affect the risk of certain cancer, such as colorectal cancer (CRC) (Platz, 2000). CRC has listed the third leading cancer among male and female in the United States (Stewart, 2014). Surprisingly, the consumption of dietary fiber has an inverse correlation with the mortality of CRC (Song, 2018). However, most Americans do not consume enough dietary fiber to meet the recommended level of dietary fiber intake (Clemens, 2012; Lee-Kwan, 2017). Hence, it is reasonable to increase the nutrient density, i.e., dietary fiber, of current food model. Xylo-oligosaccharides (XOS), an emerging prebiotics, showed multiple advantages over fructo-oligosaccharides (FOS) and inulin. For example, Hsu et al. (2004) reported XOS are more effective than FOS on increasing Bifidobacterium level in rat cecum (Hsu, 2004). It is also suggested that dietary fiber and phenolic compounds have synergistic effect on promoting gut health (Uehara, 2001; Matsukawa, 2009). Therefore, the application of XOS into a polyphenol-dense food vehicle (strawberry puree) could be a viable way to promote gastrointestinal health and help reduce CRC risk. First, the effect of xylo-oligosaccharides (XOS) incorporation on the quality attributes of strawberry puree was investigated. Rheological properties, color and physicochemical characteristics and composition such as water activity, pH, and total soluble solids, were investigated to determine the maximum XOS content that can be incorporated into the strawberry pure without significantly altering the original properties of samples. Based on the collected data, adding xylo-oligosaccharides greater than 7.5% w/w will significantly change the quality attributes of the strawberry puree including its rheological characteristics, color profile, water activity, and total soluble solids. The addition of XOS at 2.5% and 5% w/w did not significantly alter overall quality attributes of strawberry puree. Second, the effects of heat treatment (HTST, 75℃, 15s and UHT, 121℃, 2s) and storage condition (storage time: 1, 15, and 36 days; storage temperature: 4℃ and 55℃) on the quality attributes of xylo-oligosaccharides enhanced strawberry puree was studied (texture, color water activity, total soluble solids, and pH). In addition, the physicochemical (total phenolic, tannin, flavonoids contents, and antioxidant activity) evolution was studied. A 9-point Hedonic test was conducted to evaluate the sensory properties (overall, texture, color, appearance, sweetness, aroma, flavor) of purees (with and without XOS, 5%w/w) under different thermal treatments. Briefly, all nutritional attributes were retained better under cold storage (4 ℃) as compared to high-temperature storage (55 ℃). The result revealed that thermal treatment and high storage temperature showed an inverse correlation with puree consistency. As for chemical analysis, intense thermal treatment (UHT) caused the most degradation in TPC, TFC and tannin level. However, such treatments (UHT) helped significantly increase the measurable antioxidant level. For other physicochemical properties, processing methods (HTST / UHT) and high storage temperature exhibited more significance in changing the color profiles of the specimen than XOS incorporation. Overall, the addition of XOS up to 5% w/w could increase nutritional value of strawberry puree as well as consumer preference without significantly compromising quality attributes. Based on instrumental and sensory analysis, HTST treated strawberry puree with XOS incorporation (5% w/w) meet the standard of sensorial attributes of fresh puree with improved shelf-life stability and fiber concentration.

DEVELOPMENT AND VALIDATION OF A LIGHT WEIGHT, ENERGY DENSE, READY TO EAT (RTE) BAR Jacob Wilhelm-Maria Heick Providing additional calories in the form of an RTE bar to endurance athletes will increase performance and muscle re-synthesis, reduce muscle breakdown, and shorten recovery time. An RTE bar containing a blend of dairy proteins and carbohydrates will create a product with superior functionality, including bioactive and immunity enhancing properties from dairy derived ingredients. The protein will provide benefits in the form of easily digestible calories, essential amino acids and physical satiate. A formulation was developed and optimized, resulting in a final product that meets the required nutritional profile: 400kcal, 25grams protein per 100 gram serving size. The desired physical characteristics were achieved through processing by both conventional baking and freeze drying. The latter method improves the stability and functionality of the RTE bar. In order to meet the protein requirements of the RTE bar without compromising sensory properties, a unique protein source was developed. Using high concentrations of conventional protein sources like Whey Protein Concentrate (WPC) resulted in stale off-flavors and unappealing textures. Milk Protein Precipitate (MPP) was developed for this formulation. MPP is a curd-like ingredient created through the combined heat and acid precipitation of dairy proteins. MPP can be used effectively in high concentrations provides a subtle dairy flavor. MPP delivers a balance of casein and whey, similar to that found in milk. The effectiveness of the RTE bar formulation as a post exercise recovery food was evaluated in a human studies experiment conducted on the Cal Poly campus. The human subjects study utilized 34 Cal Poly students in a single-blind cross-over design experiment. The study compared the effects of this high protein RTE bar against a calorically equal carbohydrate bar. The bars were administered after subjects completed the pre-assigned hikes on three consecutive days. Following the cross-over design, subjects received the alternate bar in the second period of the experiment. Several blood markers involved in metabolism and inflammation were measured before and after the two treatment periods. No blood marker showed a statistically significant difference between bars, but several trends were observed. Body weight and fat percent were also unaffected by bar composition.

<p>  </p> <p>Fouling is a severe problem for food processing equipment, including heat exchanger, filtration system, etc., which can decrease heat transfer efficiency, increase pressure drop, and affect food quality and safety. To ensure process efficiency and product quality, regular cleaning is necessary. On manufacturing lines in the food industry, cleaning is usually performed by cleaning-in-place (CIP) operations, which mainly comprise water rinse, alkaline wash and acid wash steps. Although CIP can ensure uniform cleaning of equipment, lower costs associated with labor and plant downtime, and improve personnel safety, it consumes large amounts of energy, chemicals and water and thus affects the environmental sustainability.</p> <p>Microbubbles (MBs) are fine gas bubbles with very different physicochemical properties from millimeter-sized bubbles, including longer residence time in liquid, higher mass transfer rate, larger surface-area-to-volume ratio, and generation of free radical when bubbles collapse. In addition, MBs feature hydrophobic liquid-gas interface, allowing hydrophobic and amphipathic substances to attach to and spread on bubble surfaces. MBs have been used in cleaning processes, such as oil flotation and fresh produce washing; however, their applications in CIP operations in food processing have not been explored.</p> <p>The objective of this dissertation is to develop a novel CIP operation with the incorporation of MBs for cleaning of food processing equipment. MBs were incorporated into rinsing water to clean milk deposit fouled on heat transfer surface. A computational fluid dynamics model was built to predict the contact frequency of MBs with deposit and further identify the flow conditions that provided maximum MB-deposit contact. Moreover, MBs were confirmed to be able to attach to milk deposit by microscopic imaging. Rinsing with MB-incorporated water noticeably enhanced the deposit removal at Re of 4392 and 5403, by 27−31%. For cleaning of microfiltration membrane reversibly fouled by palm oil-in-water emulsions as model wastewater, although adding MBs into alkaline wash increased the membrane flux recovery by 235%, increasing the crossflow velocity of MB-incorporated liquid did not guarantee the enhancement in cleaning performance. Lastly, a MB-assisted full CIP process was tested on an ultrafiltration system used for milk concentration. MB-assisted CIP showed an increased cleaning efficiency with up to 72% higher flux recovery than conventional CIP, and alkaline wash with MBs added was the major step accounting for enhanced protein removal.</p> <p>Overall, this dissertation proves the effectiveness of MBs in cleaning of different types of food deposits, and provides groundwork knowledge of MB incorporation into CIP operations for different food processing equipment. The results are expected to guide the scale-up of MB-assisted CIP processes that can reduce the water and chemical usage in food manufacturing sectors, ultimately improving both economic and environmental sustainability of the food industry.</p>

Frozen, thawed and osmotically-dehydrated highbush (HB) (Vaccinium corymbosum) and rabbiteye (RB) (V. virgatum) blueberries were analyzed under a scanning electron microscope (SEM) to observe microstructural differences in their skin. Rabbiteye blueberries of both frozen, thawed and osmotically-dehydrated treatments, had thicker skins than highbush blueberries. Rabbiteye blueberries, collected from local farms, packed and blast frozen (PBF), had thinner skins than individually quick-frozen (IQF) blueberries. Washing berries prior to freezing had no effect on skin thickness. Sensory analysis of samples determined there were no differences (p > 0.05) between PBF and IQF methods and species with respect to skin intactness, grittiness, sweetness, and blueberry flavor. IQF berries obtained from one farm had tougher skin (p ≤ 0.05) than other berries regardless of treatment. RB were rated lower in juiciness and higher in grittiness than HB berries whereas LH berries were rated lower in shriveling and higher in skin intactness.

Tyrophagus putrescentiae, known as the ham mite, is the most difficult pest to control in the dry-cured ham industry. Food-grade propylene glycol coated nets have been studied as an alternative to conventional mite infestation treatments but were heavy and costly to ship. This study aimed to increase the ease of use of the coated nets via drying. Three drying treatments: oven dried for 7 min (OD7m), oven dried for 20 min (OD20m), and counter dried for 24 h (CD24h), were tested to determine the efficacy at controlling mites as well as the mechanical properties of the nets and sensory characteristics of ham wrapped in the treated nets. The OD7m and CD24h treatments were effective at controlling mite growth in a laboratory setting. The drying treatments did not affect the mechanical properties, or the sensory characteristics of the hams wrapped with the dried net treatments.

The objective of this research was to evaluate if chitosan and another food-grade compound can be incorporated into food-grade coatings in conjunction with propylene glycol and polysaccharides to control Tyrophagus putrescentiae growth without affecting sensory attributes, water activity, and moisture content of dry-cured hams. Each coating solution was coated on ham cubes (2.5 × 2.5 × 2.5 cm3, n = 5/treatment) or infused in ham nets, and dry-cured ham cubes were wrapped in the ham nets prior to inoculation with 20 mixed-sex adult mites. Randomized complete block designs with two replications were utilized to evaluate the efficacy of treatments at controlling mite growth on dry-cured ham cubes. When CH was mixed with XG and infused into a net, fewer mites (15.7 and 21.0 mites) were on ham cubes (P < 0.05) in comparison to the control (211.2 mites). Results indicated that CH contributed to controlling mite growth since 1% XG alone did not control mite growth. Difference from control test results indicated that no sensory differences existed (NS) between CH-treated and control ham slices. The addition of a food-grade compound (SP or 24P) to the XG coatings enhanced mite control efficacy. When 1% SP was added to 1% XG, it effectively controlled mite growth in both coating and netting treatments. Increasing 1% SP to 2% SP did not significantly (NS) control mite growth in the coating solution but did control mite growth when infused in the net. Both coating and netting treatments with 2% 24P + 1% XG controlled mite growth. When 24P was the only ingredient in the treatment, both 1% and 2% 24P controlled mites when infused in the net. The addition of SP did not (NS) impact the sensory attributes of the dry-cured ham. The 2% 24P + 1% XG treatment differed in moistness (P < 0.05) when compared to the blind control, but the rating was still less than 2 (moderately different). Overall, results from these studies indicate that chitosan can potentially be added in coatings or ham nets as tools to control mites in an integrated pest management program for dry-cured hams.

En el marco de esta investigación, se realizó un análisis del proceso de pilado de arroz ejecutado por la empresa SAN FABRI SAC, con el objetivo de incrementar su productividad. Este estudio comprendió una evaluación detallada de la situación actual de la empresa, abarcando la identificación de indicadores relacionados con la producción, productividad, eficiencia y capacidad. La productividad total se estableció en 0,4 sacos de arroz pilado/soles. Asimismo, se procedió a identificar las actividades del proceso mediante un cursograma analítico, revelando que la etapa de secado, realizada artesanalmente con una duración de 2880 minutos y una eficiencia del 56,20%, era el principal factor limitante. De igual manera, se detectó que la falta de mantenimiento preventivo generó 53 fallos en 2022, con un total de 513 horas de tiempo de parada. Conociendoxlasxcausas, se propuso la implementación de una secadora industrial y un plan de mantenimiento preventivo, logrando un aumento del 65% en la productividad global, un incremento del 22,54% en la eficiencia del proceso y una disminución del 69,57% en la capacidad ociosa. Por último, gracias a un análisis de costobeneficio, reveló que la empresa obtiene una ganancia de S/.0,68 por cada sol invertido. / In this research, an analysis of the rice piling process carried out by the company SAN FABRI SAC was carried out, with the aim of increasing its productivity. This study included a detailed evaluation of the current situation of the company, covering the identification of indicators related to production, productivity, efficiency and capacity. Total productivity was established at 0.4 bags of piled rice/soles. The process activities were identified using an analytical course, revealing that the drying stage, carried out by hand with a duration of 2880 minutes and an efficiency of 56.20%, was the main limiting factor. In addition, it was detected that the lack of preventive maintenance generated 53 failures in 2022, with 513 hours of downtime. In response, the implementation of an industrial dryer and a preventive maintenance plan was proposed, achieving a 65% increase in global productivity, a 22.54% increase in process efficiency and a 69.57% decrease in idle capacity. Finally, thanks to a cost-benefit analysis, it revealed a profit of S/. 0.68 for each sol invested.